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Liu Y, Liu J, Xiao J, Ye J, Guo L, Yan C. Metrological traceable calibration of organic carbon and elemental carbon based on laboratory-generated reference materials. J Environ Sci (China) 2025; 149:524-534. [PMID: 39181664 DOI: 10.1016/j.jes.2023.10.031] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2023] [Revised: 10/25/2023] [Accepted: 10/25/2023] [Indexed: 08/27/2024]
Abstract
Carbonaceous aerosol, including organic carbon (OC) and elemental carbon (EC), has significant influence on human health, air quality and climate change. Accurate measurement of carbonaceous aerosol is essential to reduce the uncertainty of radiative forcing estimation and source apportionment. The accurate separation of OC and EC is controversial due to the charring of OC. Therefore, the development of reference materials (RM) for the validation of OC/EC separation is an important basis for further study. Previous RMs were mainly based on ambient air sampling, which could not provide traceability of OC and EC concentration. To develop traceable RMs with known OC/EC contents, our study applied an improved aerosol generation and mixing technique, providing uniform deposition of particles on quartz filters. To generate OC aerosol with similar pyrolytic property of ambient aerosol, both water soluble organic carbon (WSOC) and water insoluble organic carbon (WIOC) were used, and amorphous carbon was selected for EC surrogate. The RMs were analyzed using different protocols. The homogeneity within the filter was validated, reaching below 2%. The long-term stability of RMs has been validated with RSD ranged from 1.7%-3.2%. Good correlation was observed between nominal concentration of RMs with measured concentration by two protocols, while the difference of EC concentration was within 20%. The results indicated that the newly developed RMs were acceptable for the calibration of OC and EC, which could improve the accuracy of carbonaceous aerosol measurement. Moreover, the laboratory-generated EC-RMs could be suitable for the calibration of equivalent BC concentration by Aethalometers.
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Affiliation(s)
- Yue Liu
- Center for Environmental Metrology, National Institute of Metrology China, Beijing 100029, China
| | - Junjie Liu
- Center for Environmental Metrology, National Institute of Metrology China, Beijing 100029, China.
| | - Ji Xiao
- Center for Environmental Metrology, National Institute of Metrology China, Beijing 100029, China
| | - Jing Ye
- College of Chemistry and Chemical Engineering, Taiyuan University of Technology, Taiyuan 030024, China
| | - Lixu Guo
- College of Chemistry and Chemical Engineering, Taiyuan University of Technology, Taiyuan 030024, China
| | - Caiqing Yan
- Environment Research Institute, Shandong University, Qingdao 266237, China
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2
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Zhang Y, Han Y, Dong L, Deng X, Ye D, Shao S. Spatiotemporal variations and source on black carbon over Chongqing, China: Long-term changes and observational experiments. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 946:174127. [PMID: 38908574 DOI: 10.1016/j.scitotenv.2024.174127] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2024] [Revised: 06/16/2024] [Accepted: 06/17/2024] [Indexed: 06/24/2024]
Abstract
Black carbon (BC), as a critical light-absorbing constituent within aerosols, exerts profound effects on atmospheric radiation balance, climate, air quality and human health, etc. And it is also a long-standing focus in rapidly developing megacities. So, this study primarily focuses on investigating the variation characteristics and underlying causes of BC in Chongqing (31,914,300 population), which is one of the municipalities directly under the central government of China, serving as a pivotal economic hub in southwest China. Utilizing MERRA-2 reanalysis data, we examined the long-term changes of atmospheric BC over Chongqing 20 years (from 2002 to 2021). Moreover, BC mass concentration observations were conducted using an Aethalometer (AE-33) from March 15 to June 14, 2021 in Liangping District, Chongqing. The statistical analysis over the last 20 years reveals an annual mean BC concentration in Chongqing of 3.42 ± 0.20 μg/m3, exhibiting growth from 2002 to 2008, followed by a decline from 2008 to 2021. Monthly concentration displays a "U-shaped" trend, with the lowest values occurring in summer and the highest in winter. Due to topographical and meteorological influences, local emissions primarily contribute to BC pollution, characterized by a spatial distribution pattern of high in the west and low in the east. Ground observation indicates a distinct dual-peaked pattern in the diurnal variation of BC, with peak concentrations aligning with periods of high traffic emissions. The variation in BC is significantly influenced by meteorological conditions (wind, temperature, atmospheric boundary layer) and local pollution sources (predominantly traffic). Furthermore, extreme events analysis suggests that local emissions and regional transport (with higher contributions from Chongqing and the Sichuan Basin) predominantly contributed to BC pollution. This study effectively makes up for the deficiency in analyzing the distribution and sources of BC pollution in Chongqing, providing valuable scientific insights for the atmospheric environment of megacities.
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Affiliation(s)
- Yurong Zhang
- Advanced Science & Technology of Space and Atmospheric Physics Group (ASAG), School of Atmospheric Sciences, Sun Yat-sen University, Zhuhai 519082, China
| | - Yong Han
- Advanced Science & Technology of Space and Atmospheric Physics Group (ASAG), School of Atmospheric Sciences, Sun Yat-sen University, Zhuhai 519082, China.
| | - Li Dong
- Advanced Science & Technology of Space and Atmospheric Physics Group (ASAG), School of Atmospheric Sciences, Sun Yat-sen University, Zhuhai 519082, China
| | - Ximing Deng
- Advanced Science & Technology of Space and Atmospheric Physics Group (ASAG), School of Atmospheric Sciences, Sun Yat-sen University, Zhuhai 519082, China
| | - Dan Ye
- Advanced Science & Technology of Space and Atmospheric Physics Group (ASAG), School of Atmospheric Sciences, Sun Yat-sen University, Zhuhai 519082, China
| | - Shiyong Shao
- Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei 230031, China
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3
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Ding S, Zhao D, Tian P, Huang M. Source apportionment and wet scavenging ability of atmospheric black carbon during haze in Northeast China. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 357:124470. [PMID: 38950848 DOI: 10.1016/j.envpol.2024.124470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2024] [Revised: 06/14/2024] [Accepted: 06/27/2024] [Indexed: 07/03/2024]
Abstract
Seasonal variations in black carbon (BC) pollution characteristics during haze episodes in Benxi city, Liaoning province, were analyzed using year-long measurements of BC, carbon monoxide (CO), and PM2.5. Haze frequencies were recorded to be 0.07, 0.03 and 0.14 in spring, autumn, and winter respectively. Solid fuel contributions increased notably by 7%-8% during haze events compared to clean periods in all seasons. Transitioning from clean to haze periods led to ΔBC/ΔCO increases of 16% in spring and autumn, and 6.8% in winter, while BC/PM2.5 ratios decreased by approximately 33%, 50%, and 24% for spring, autumn, and winter respectively, likely indicating enhanced residential and industrial contributions. These further led to an increase in BC absorption capacities by factors of around 2.2 in spring and autumn, and up to 2.6 in winter during haze periods. Despite liquid fuel sources dominating BC emissions, certain haze episodes (frequency <10%) showed solid fuel contributions of up to 65%, highlighting BC pollution complexity in the region during haze. Backward trajectories analysis revealed local air masses from Liaoning province arrived consistently with the most occurrence of haze events across all seasons, while long-range air masses from Mongolian regions, though with less frequent occurrence during haze periods, significantly elevated BC loadings from solid fuel sources, particularly in spring and autumn due to biomass burning. Despite higher BC wet scavenging rates (WSR) in long-range air masses (0.072 ng m-3 ppbv-1 mm-1) compared to local air masses (0.039 ng m-3 ppbv-1 mm-1), significant BC transport persisted due to limited precipitation along transport pathways, especially during haze periods. These findings provide crucial insights for policymakers, highlighting the need for targeted haze prevention and control strategies focusing on mitigating BC emissions in Northeast China.
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Affiliation(s)
- Shuo Ding
- Department of Environmental Engineering, College of Energy Environment and Safety Engineering, China Jiliang University, Hangzhou, 310018, China; College of Carbon Metrology, China Jiliang University, Hangzhou, 310018, China.
| | - Delong Zhao
- Beijing Weather Modification Office, Beijing, 100089, China
| | - Ping Tian
- Beijing Weather Modification Office, Beijing, 100089, China
| | - Mengyu Huang
- Beijing Weather Modification Office, Beijing, 100089, China
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Chelluboyina GS, Kapoor TS, Chakrabarty RK. Dark brown carbon from wildfires: a potent snow radiative forcing agent? NPJ CLIMATE AND ATMOSPHERIC SCIENCE 2024; 7:200. [PMID: 39220727 PMCID: PMC11357999 DOI: 10.1038/s41612-024-00738-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/21/2024] [Accepted: 08/07/2024] [Indexed: 09/04/2024]
Abstract
Deposition of wildfire smoke on snow contributes to its darkening and accelerated snowmelt. Recent field studies have identified dark brown carbon (d-BrC) to contribute 50-75% of shortwave absorption in wildfire smoke. d-BrC is a distinct class of water-insoluble, light-absorbing organic carbon that co-exists in abundance with black carbon (BC) in snow across the world. However, the importance of d-BrC as a snow warming agent relative to BC remains unexplored. We address this gap using aerosol-snow radiative transfer calculations on datasets from laboratory and field measurement. We show d-BrC increases the annual mean snow radiative forcing between 0.6 and 17.9 W m- 2, corresponding to different wildfire smoke deposition scenarios. This is a 1.6 to 2.1-fold enhancement when compared with BC-only deposition on snow. This study suggests d-BrC is an important contributor to snowmelt in midlatitude glaciers, where ~40% of the world's glacier surface area resides.
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Affiliation(s)
- Ganesh S. Chelluboyina
- Center for Aerosol Science and Engineering, Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, MO USA
| | - Taveen S. Kapoor
- Center for Aerosol Science and Engineering, Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, MO USA
| | - Rajan K. Chakrabarty
- Center for Aerosol Science and Engineering, Department of Energy, Environmental and Chemical Engineering, Washington University in St. Louis, St. Louis, MO USA
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Liu Y, Xu X, Ji D, He J, Wang Y. Examining trends and variability of PM 2.5-associated organic and elemental carbon in the megacity of Beijing, China: Insight from decadal continuous in-situ hourly observations. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 938:173331. [PMID: 38777070 DOI: 10.1016/j.scitotenv.2024.173331] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2024] [Revised: 04/24/2024] [Accepted: 05/15/2024] [Indexed: 05/25/2024]
Abstract
Organic carbon (OC) and elemental carbon (EC) in fine particulate matter (PM2.5) play pivotal roles in impacting human health, air quality, and climate change dynamics. Long-term monitoring datasets of OC and EC in PM2.5 are indispensable for comprehending their temporal variations, spatial distribution, evolutionary patterns, and trends, as well as for assessing the effectiveness of clean air action plans. This study presents and scrutinizes a comprehensive 10-year hourly dataset of PM2.5-bound OC and EC in the megacity of Beijing, China, spanning from 2013 to 2022. Throughout the entire study period, the average concentrations of OC and EC were recorded at 8.8 ± 8.7 and 2.5 ± 3.0 μg/m3, respectively. Employing the seasonal and trend decomposition methodology, specifically the locally estimated scatter plot smoothing method combined with generalized least squares with the autoregressive moving average method, the study observed a significant decline in OC and EC concentrations, reducing by 5.8 % yr-1 and 9.9 % yr-1 at rates of 0.8 and 0.4 μg/m3 yr-1, respectively. These declining trends were consistently verified using Theil-Sen method. Notably, the winter months exhibited the most substantial declining trends, with rates of 9.3 % yr-1 for OC and 10.9 % yr-1 for EC, aligning with the positive impact of the implemented clean air action plan. Weekend spikes in OC and EC levels were attributed to factors such as traffic regulations and residential emissions. Diurnal variations showcased higher concentrations during nighttime and lower levels during daytime. Although meteorological factors demonstrated an overall positive impact with average reduction in OC and EC concentrations by 8.3 % and 8.7 %, clean air action plans including the Air Pollution Prevention and Control Action Plan (2013-2017) and the Three-Year Action Plan to Win the Blue Sky War (2018-2020) have more contributions in reducing the OC and EC concentrations with mass drop rates of 87.1 % and 89.2 % and 76.7 % and 96.7 %, respectively. Utilizing the non-parametric wind regression method, significant concentration hotspots were identified at wind speeds of ≤2 m/s, with diffuse signals recorded in the southwestern wind sectors at wind speeds of approximately 4-5 m/s. Interannual disparities in potential source regions of OC and EC were evident, with high potential source areas observed in the southern and northwestern provinces of Beijing from 2013 to 2018. In contrast, during 2019-2022, potential source areas with relatively high values of potential source contribution function were predominantly situated in the southern regions of Beijing. This analysis, grounded in observational data, provides insights into the decadal changes in the major atmospheric composition of PM2.5 and facilitates the evaluation of the efficacy of control policies, particularly relevant for developing countries.
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Affiliation(s)
- Yu Liu
- State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China; University of Chinese Academy of Sciences, Beijing 100049, China; Atmosphere Sub-Center of Chinese Ecosystem Research Network, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100191, China
| | - Xiaojuan Xu
- University of Chinese Academy of Sciences, Beijing 100049, China; Atmosphere Sub-Center of Chinese Ecosystem Research Network, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100191, China
| | - Dongsheng Ji
- State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China; University of Chinese Academy of Sciences, Beijing 100049, China; Atmosphere Sub-Center of Chinese Ecosystem Research Network, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100191, China.
| | - Jun He
- Department of Chemical and Environmental Engineering, University of Nottingham Ningbo China, Ningbo 315100, China; Nottingham Ningbo China Beacons of Excellence Research and Innovation Institute, Ningbo 315100, China
| | - Yuesi Wang
- State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China; University of Chinese Academy of Sciences, Beijing 100049, China; Atmosphere Sub-Center of Chinese Ecosystem Research Network, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100191, China
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6
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Guerrero F, Espinoza L, Vidal V, Carmona C, Krecl P, Targino AC, Ruggeri MF, Toledo M. Black carbon and particulate matter concentrations amid central Chile's extreme wildfires. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 951:175541. [PMID: 39151628 DOI: 10.1016/j.scitotenv.2024.175541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2024] [Revised: 08/02/2024] [Accepted: 08/13/2024] [Indexed: 08/19/2024]
Abstract
The increase in the frequency and severity of global wildfires has been largely influenced by climate change and land use changes. From February 2 to 6, 2024, central Chile experienced its most devastating wildland-urban interface wildfire in history, severely impacting the Valparaíso region. This catastrophic event, which led to extensive forest destruction, the loss of thousands of homes, and over a hundred human fatalities, directly impacted the area surrounding the campus of Federico Santa María Technical University. In that period, an air quality monitoring campaign was set up on the campus to measure black carbon (BC) and particulate matter (PM) during the wildfire season. The monitoring station was located directly within the smoke plume, allowing for the collection of unprecedented air quality data. Extremely high concentrations of BC at 880 nm were reported during the wildfires, with a daily mean (±σ) of 14.83 ± 19.52 μg m-3. Peak concentrations measured at 880 nm and 375 nm reached 812.89 μg m-3 and 1561.24 μg m-3, respectively. The maximum daily mean BC concentrations at these wavelengths were 55 and 99 times higher, respectively, compared to the pre-event period. The mean Ångström absorbing coefficient during the event was 1.66, indicating biomass burning as the primary BC source, while the maximum BC/PM2.5 ratio (at 375 nm) reached 57 %. From February 2 to 5, 2024, PM concentrations exceeded the Chilean air quality standard by 82 % and 198 % for coarse and fine particles, respectively. These levels are 4.7 and 6.0 times higher than the World Health Organization's recommendations. These elevated concentrations persisted for up to three days after the fire was extinguished. This study provides unique evidence of the rapid deterioration of regional air quality during a wildfire event using in situ measurements, serving as a stark reminder of the far-reaching consequences of a warming climate.
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Affiliation(s)
- Fabián Guerrero
- Department of Mechanical Engineering, Universidad Técnica Federico Santa María, Avenida España 1680, 23400000 Valparaíso, Chile.
| | - Lorena Espinoza
- Department of Mechanical Engineering, Universidad Técnica Federico Santa María, Avenida España 1680, 23400000 Valparaíso, Chile
| | - Víctor Vidal
- Estudios Ambientales y Asesorías Limitada (E2A), Reñaca Norte 25, of. 608, 2542629 Viña del Mar, Valparaíso, Chile
| | - Camilo Carmona
- Department of Mechanical Engineering, Universidad Técnica Federico Santa María, Avenida España 1680, 23400000 Valparaíso, Chile
| | - Patricia Krecl
- Graduate Program in Environmental Engineering, Federal University of Technology, Av. Pioneiros 3131, 86036-370 Londrina, PR, Brazil
| | - Admir Créso Targino
- Graduate Program in Environmental Engineering, Federal University of Technology, Av. Pioneiros 3131, 86036-370 Londrina, PR, Brazil
| | - María F Ruggeri
- Centre for Environmental Technologies, Universidad Técnica Federico Santa María, Avenida España 1680, 23400000 Valparaíso, Chile
| | - Mario Toledo
- Department of Mechanical Engineering, Universidad Técnica Federico Santa María, Avenida España 1680, 23400000 Valparaíso, Chile
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Duvall R, Kimbrough S, Krabbe S, Deshmukh P, Baldauf R, Brouwer L, McArthur T, Croghan C, Varga J, Brown M, Davis M. Analysis of PM 2.5, black carbon, and trace metals measurements from the Kansas City Transportation and Local-Scale Air Quality Study (KC-TRAQS). JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION (1995) 2024; 74:581-594. [PMID: 38874903 PMCID: PMC11361304 DOI: 10.1080/10962247.2024.2365708] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Accepted: 05/29/2024] [Indexed: 06/15/2024]
Abstract
Communities near transportation sources can be impacted by higher concentrations of particulate matter (PM) and other air pollutants. Few studies have reported on air quality in complex urban environments with multiple transportation sources. To better understand these environments, the Kansas City Transportation and Local-Scale Air Quality Study (KC-TRAQS) was conducted in three neighborhoods in Southeast Kansas City, Kansas. This area has several emissions sources including transportation (railyards, vehicles, diesel trucks), light industry, commercial facilities, and residential areas. Stationary samples were collected for 1-year (October 24, 2017, to October 31, 2018) at six sites using traditional sampling methods and lower-cost air sensor packages. This work examines PM less than 2.5 μm in diameter (PM2.5), black carbon (BC), and trace metals data collected during KC-TRAQS. PM2.5 filter samples showed the highest 24-h mean concentrations (9.34 μg/m3) at the sites located within 20-50 m of the railyard. Mean 24-h PM2.5 concentrations, ranging from 7.96 to 9.34 μg/m3, at all sites were lower than that of the nearby regulatory site (9.83 μg/m3). Daily maximum PM2.5 concentrations were higher at the KC-TRAQS sites (ranging from 25.31 to 43.76 μg/m3) compared to the regulatory site (20.50 μg/m3), suggesting short-duration impacts of localized emissions sources. Across the KC-TRAQS sites, 24-h averaged PM2.5 concentrations from the sensor package (P-POD) ranged from 3.24 to 5.69 µg/m3 showing that, out-of-the-box, the PM sensor underestimated the reference concentrations. KC-TRAQS was supplemented by elemental and organic carbon (EC/OC) and trace metal analysis of filter samples. The EC/OC data suggested the presence of secondary organic aerosol formation, with the highest mean concentrations observed at the site within 20 m of the railyard. Trace metals data showed daily, monthly, and seasonal variations for iron, copper, zinc, chromium, and nickel, with elevated concentrations occurring during the summer at most of the sites.Implications: This work reports on findings from a year-long air quality study in Southeast Kansas City, Kansas to understand micro-scale air quality in neighborhoods impacted by multiple emissions sources such as transportation sources (including a large railyard operation), light industry, commercial facilities, and residential areas. While dozens of studies have reported on air quality near roadways, this work will provide more information on PM2.5, black carbon, and trace metals concentrations near other transportation sources in particular railyards. This work can also inform additional field studies near railyards.
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Affiliation(s)
- Rachelle Duvall
- U.S. Environmental Protection Agency, Office of Research and Development, 109 T.W. Alexander Drive, Research Triangle Park, NC, 27711, USA
| | - Sue Kimbrough
- U.S. Environmental Protection Agency, Office of Research and Development, 109 T.W. Alexander Drive, Research Triangle Park, NC, 27711, USA
| | - Stephen Krabbe
- U.S. Environmental Protection Agency, Region 7, 300 Minnesota Avenue, Kansas City, KS, 66101, USA
| | - Parikshit Deshmukh
- Jacobs Technologies Inc., 109 T.W. Alexander Drive, Research Triangle Park, NC 27711, USA
| | - Richard Baldauf
- U.S. Environmental Protection Agency, Office of Research and Development, 109 T.W. Alexander Drive, Research Triangle Park, NC, 27711, USA
| | - Lydia Brouwer
- Jacobs Technologies Inc., 109 T.W. Alexander Drive, Research Triangle Park, NC 27711, USA
| | - Timothy McArthur
- Science Systems and Applications Inc., 109 T.W. Alexander Drive, Research Triangle Park, NC, 27711, USA
| | - Carry Croghan
- U.S. Environmental Protection Agency, Office of Research and Development, 109 T.W. Alexander Drive, Research Triangle Park, NC, 27711, USA
| | - Joshua Varga
- Jacobs Technologies Inc., 109 T.W. Alexander Drive, Research Triangle Park, NC 27711, USA
| | - Matthew Brown
- U.S. Environmental Protection Agency, Region 7, 300 Minnesota Avenue, Kansas City, KS, 66101, USA
| | - Michael Davis
- U.S. Environmental Protection Agency, Region 7, 300 Minnesota Avenue, Kansas City, KS, 66101, USA
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Rajesh TA, Ramachandran S. Atmospheric black carbon aerosol: Long-term characteristics, source apportionment, and trends. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 934:172928. [PMID: 38754497 DOI: 10.1016/j.scitotenv.2024.172928] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2024] [Revised: 04/25/2024] [Accepted: 04/29/2024] [Indexed: 05/18/2024]
Abstract
Black carbon (BC) aerosols play a very significant role in influencing air quality, climate, and human health. Large uncertainties still exist in BC emissions due to limited observations on the relative source contributions of fossil fuel (ff) combustion and biomass (wood fuel, wf) burning. Our understanding of long-term changes in BC emissions, especially their source apportionment, is sparse and limited. For the first time, BC characteristics, its source apportionment into ff and wf components, and their trends measured using a multi-wavelength aethalometer over an urban location (Ahmedabad) in India covering a 14 year period (2006-2019) are comprehensively investigated. The average contributions of eBCff and eBCwf concentrations to total eBC are 80 % and 20 %, respectively, which highlights the dominance of emissions from fossil fuel combustion processes. A statistically significant increasing trend in eBC and eBCff mass concentrations at the rate of 11 % and 29%yr-1, respectively, and a decreasing trend in eBCwf concentration at the rate of 36%yr-1 are detected. The study reveals a significant decrease in biomass (wood fuel) burning emissions over the past decade and an increase in emissions from fossil fuel combustion. However, the rates of increase and decrease in eBCff and eBCwf are different, which indicate that rapid urbanization led to an increase in anthropogenic emissions, whereas an increase in usage of non-polluting fuel led to a decreasing trend in wood burning contribution. During weekdays and weekends, eBC and eBCff mass concentrations did not exhibit any statistically significant trends. However, eBCwf concentration shows a statistically significant decreasing trend during weekdays 34%yr-1 and weekends 38%yr-1. Globally, several countries are adopting various strategies and mitigation policies to improve air quality; however, significant gaps exist in their implementation towards achieving cleaner air and less polluted environment. This comprehensive study is relevant for understanding the impact of urbanization and devising better BC emission control policies.
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Affiliation(s)
- T A Rajesh
- Space and Atmospheric Sciences Division, Physical Research Laboratory, Ahmedabad 380009, India.
| | - S Ramachandran
- Space and Atmospheric Sciences Division, Physical Research Laboratory, Ahmedabad 380009, India
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Kong Y, Zhi G, Jin W, Zhang Y, Shen Y, Li Z, Sun J, Ren Y. A review of quantification methods for light absorption enhancement of black carbon aerosol. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 924:171539. [PMID: 38462012 DOI: 10.1016/j.scitotenv.2024.171539] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Revised: 02/28/2024] [Accepted: 03/04/2024] [Indexed: 03/12/2024]
Abstract
Black carbon (BC) is a distinct type of carbonaceous aerosol that has a significant impact on the environment, human health, and climate. A non-BC material coating on BC can alter the mixing state of the BC particles, which considerably enhances the mass absorption efficiency of BC by directing more energy toward the BC cores (lensing effect). A lot of methods have been reported for quantifying the enhancement factor (Eabs), with diverse results. However, to the best of our knowledge, a comprehensive review specific to the quantification methods for Eabs has not been systematically performed, which is unfavorable for the evaluation of obtained results and subsequent radiative forcing. In this review, quantification methods are divided into two broad categories, direct and indirect, depending on whether experimental removal of the coating layer from an aged carbonaceous particle is required. The direct methods described include thermal peeling, solvent dissolution, and optical virtual exfoliation, while the indirect methods include intercept-linear regression fitting, minimum R squared, numerical simulation, and empirical value. We summarized the principles, procedures, virtues, and limitations of the major Eabs quantification methods and analyzed the current problems in the determination of Eabs. We pointed out what breakthroughs are needed to improve or innovate Eabs quantification methods, particularly regarding the need to avoid the influence of brown carbon, develop a broadband Eabs quantification scheme, quantify the Eabs values for the emissions of low-efficiency combustions, measure the Eabs of particles in a high-humidity environment, design a real-time monitor of Eabs by a proper combination of mature techniques, and make more use of artificial intelligence for better Eabs quantification. This review deepens the understanding of Eabs quantification methods and benefits the estimation of the contribution of BC to radiative forcing using climate models.
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Affiliation(s)
- Yao Kong
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; Institute of Atmospheric Environment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Guorui Zhi
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; Institute of Atmospheric Environment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
| | - Wenjing Jin
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; Institute of Atmospheric Environment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Yuzhe Zhang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; Institute of Atmospheric Environment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China.
| | - Yi Shen
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; Institute of Atmospheric Environment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Zhengying Li
- Beijing Municipal Ecological and Environmental Monitoring Center, Beijing 100048, China
| | - Jianzhong Sun
- School of Physical Education, Chizhou University, Chizhou, Anhui 247000, China
| | - Yanjun Ren
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; Institute of Atmospheric Environment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
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10
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Calderon-Arrieta D, Morales AC, Hettiyadura APS, Estock TM, Li C, Rudich Y, Laskin A. Enhanced Light Absorption and Elevated Viscosity of Atmospheric Brown Carbon through Evaporation of Volatile Components. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:7493-7504. [PMID: 38637508 DOI: 10.1021/acs.est.3c10184] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 04/20/2024]
Abstract
Samples of brown carbon (BrC) material were collected from smoke emissions originating from wood pyrolysis experiments, serving as a proxy for BrC representative of biomass burning emissions. The acquired samples, referred to as "pyrolysis oil (PO1)," underwent subsequent processing by thermal evaporation of their volatile compounds, resulting in a set of three additional samples with volume reduction factors of 1.33, 2, and 3, denoted as PO1.33, PO2, and PO3. The chemical compositions of these POx samples and their BrC chromophore features were analyzed using a high-performance liquid chromatography instrument coupled with a photodiode array detector and a high-resolution mass spectrometer. The investigation revealed a noteworthy twofold enhancement of BrC light absorption observed for the progression of PO1 to PO3 samples, assessed across the spectral range of 300-500 nm. Concurrently, a decrease in the absorption Ångstrom exponent (AAE) from 11 to 7 was observed, indicating a weaker spectral dependence. The relative enhancement of BrC absorption at longer wavelengths was more significant, as exemplified by the increased mass absorption coefficient (MAC) measured at 405 nm from 0.1 to 0.5 m2/g. Molecular characterization further supports this darkening trend, manifesting as a depletion of small oxygenated, less absorbing monoaromatic compounds and the retention of relatively large, less polar, more absorbing constituents. Noteworthy alterations of the PO1 to PO3 mixtures included a reduction in the saturation vapor pressure of their components and an increase in viscosity. These changes were quantified by the mean values shifting from approximately 1.8 × 103 μg/m3 to 2.3 μg/m3 and from ∼103 Pa·s to ∼106 Pa·s, respectively. These results provide quantitative insights into the extent of BrC aerosol darkening during atmospheric aging through nonreactive evaporation. This new understanding will inform the refinement of atmospheric and chemical transport models.
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Affiliation(s)
- Diego Calderon-Arrieta
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Ana C Morales
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | | | - Taylor M Estock
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Chunlin Li
- Department of Earth and Planetary Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Yinon Rudich
- Department of Earth and Planetary Sciences, Weizmann Institute of Science, Rehovot 76100, Israel
| | - Alexander Laskin
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
- Department of Earth, Atmospheric and Planetary Sciences, Purdue University, West Lafayette, Indiana 47907, United States
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11
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Qu Y, Liu H, Zhang T, Su H, Wang N, Zhou Y, Shi J, Wang L, Wang Q, Liu S, Zhu C, Cao J. Source-specific light absorption and radiative effects decreases and indications due to the lockdown. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 356:120600. [PMID: 38547823 DOI: 10.1016/j.jenvman.2024.120600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2023] [Revised: 02/13/2024] [Accepted: 03/10/2024] [Indexed: 04/07/2024]
Abstract
The 'extreme' emission abatement during the lockdown (from the end of 2019 to the early 2020) provided an experimental period to investigate the corresponding source-specific effects of aerosol. In this study, the variations of source-specific light absorption (babs) and direct radiative effect (DRE) were obtained during and after the lockdown period by using the artificial neural network (ANN) and source apportionment environmental receptor model. The results showed that the babs decreased for all sources during the two periods. The most reductions were observed with ∼90% for traffic-related emissions (during the lockdown) and ∼85% for coal combustion (after the lockdown), respectively. Heightened babs (370 nm) values were obtained for coal and biomass burning during the lockdown, which was attributed to the enhanced atmospheric oxidization capacity. Nevertheless, the variations of babs (880 nm) after the lockdown was mainly due to the weakening of oxidation and reduced emissions of secondary precursors. The present study indicated that the large-scale emission reduction can promote both reductions of babs (370 nm) and DRE (34-68%) during the lockdown. The primary emissions decrease (e.g., Traffic emission) may enhance atmosphere oxidation, increase the ultraviolet wavelength light absorption and DRE efficiencies. The source-specific emission reduction may be contributed to various radiation effects, which is beneficial for the adopting of control strategies.
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Affiliation(s)
- Yao Qu
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, 710061, China; National Observation and Research Station of Regional Ecological Environment Change and Comprehensive Management in the Guanzhong Plain, Shaanxi, Xi'an, 710499, China; University of Chinese Academy of Sciences, Beijing, 100049, China
| | - Huikun Liu
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, 710061, China; National Observation and Research Station of Regional Ecological Environment Change and Comprehensive Management in the Guanzhong Plain, Shaanxi, Xi'an, 710499, China
| | - Ting Zhang
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, 710061, China; National Observation and Research Station of Regional Ecological Environment Change and Comprehensive Management in the Guanzhong Plain, Shaanxi, Xi'an, 710499, China
| | - Hui Su
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, 710061, China; National Observation and Research Station of Regional Ecological Environment Change and Comprehensive Management in the Guanzhong Plain, Shaanxi, Xi'an, 710499, China; Xi'an Institute for Innovative Earth Environment Research, Xi'an, 710061, China
| | - Nan Wang
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, 710061, China; National Observation and Research Station of Regional Ecological Environment Change and Comprehensive Management in the Guanzhong Plain, Shaanxi, Xi'an, 710499, China; Xi'an Institute for Innovative Earth Environment Research, Xi'an, 710061, China
| | - Yue Zhou
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, 710061, China; National Observation and Research Station of Regional Ecological Environment Change and Comprehensive Management in the Guanzhong Plain, Shaanxi, Xi'an, 710499, China
| | - Julian Shi
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, 710061, China; National Observation and Research Station of Regional Ecological Environment Change and Comprehensive Management in the Guanzhong Plain, Shaanxi, Xi'an, 710499, China; Xi'an Institute for Innovative Earth Environment Research, Xi'an, 710061, China
| | - Luyao Wang
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, 710061, China; National Observation and Research Station of Regional Ecological Environment Change and Comprehensive Management in the Guanzhong Plain, Shaanxi, Xi'an, 710499, China; Xi'an Institute for Innovative Earth Environment Research, Xi'an, 710061, China
| | - Qiyuan Wang
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, 710061, China; National Observation and Research Station of Regional Ecological Environment Change and Comprehensive Management in the Guanzhong Plain, Shaanxi, Xi'an, 710499, China
| | - Suixin Liu
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, 710061, China; National Observation and Research Station of Regional Ecological Environment Change and Comprehensive Management in the Guanzhong Plain, Shaanxi, Xi'an, 710499, China
| | - Chongshu Zhu
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, 710061, China; National Observation and Research Station of Regional Ecological Environment Change and Comprehensive Management in the Guanzhong Plain, Shaanxi, Xi'an, 710499, China.
| | - Junji Cao
- State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, 710061, China; Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, 100029, China
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12
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Lan Y, Zhou L, Liu S, Wan R, Wang N, Chen D, Li Y, Jiang Y, Rao Z, Jiang W, Song D, Tan Q, Yang F. Light absorption enhancement of black carbon and its impact factors during winter in a megacity of the Sichuan Basin, China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 918:170374. [PMID: 38307267 DOI: 10.1016/j.scitotenv.2024.170374] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2023] [Revised: 01/07/2024] [Accepted: 01/21/2024] [Indexed: 02/04/2024]
Abstract
Carbonaceous aerosols play a vital role in global climate patterns due to their potent light absorption capabilities. However, the light absorption enhancement effect (Eabs) of black carbon (BC) is still subject to great uncertainties due to factors such as the mixing state, coating material, and particle size distribution. In this study, fine particulate matter (PM2.5) samples were collected in Chengdu, a megacity in the Sichuan Basin, during the winter of 2020 and 2021. The chemical components of PM2.5 and the light absorption properties of BC were investigated. The results revealed that secondary inorganic aerosols and carbonaceous aerosols were the dominant components in PM2.5. Additionally, the aerosol filter filtration-dissolution (AFD) treatment could improve the accuracy of measuring elemental carbon (EC) through thermal/optical analysis. During winter in Chengdu, the absorption enhancement values of BC ranged between 1.56 and 2.27, depending on the absorption wavelength and the mixing state of BC and non-BC materials. The presence of internally mixed BC and non-BC materials significantly contributed to Eabs, accounting for an average of 68 % at 405 nm and 100 % at 635 nm. The thickness of the BC coating influenced Eabs, displaying an increasing-then-decreasing trend. This trend was primarily attributed to the hygroscopic growth and dehydration shrinkage of particulate matter. Nitrate, as the major component of BC coating, played a crucial role in the lensing effect and exhibited fast growth during variation in Eabs. By combining the results from PMF, we identified the secondary formation and vehicle emission as the primary contributors to Eabs. Consequently, this study can provide valuable insights into the optical parameters, which are essential for assessing the environmental quality, improving regional atmospheric conditions, and formulating effective air pollution control strategies.
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Affiliation(s)
- Yuting Lan
- College of Architecture and Environment, Sichuan University, Chengdu 610065, China; College of Carbon Neutrality Future Technology, Sichuan University, Chengdu 610065, China; Sichuan University Yibin Park, Yibin Institute of Industrial Technology, Yibin 644600, China
| | - Li Zhou
- College of Architecture and Environment, Sichuan University, Chengdu 610065, China; College of Carbon Neutrality Future Technology, Sichuan University, Chengdu 610065, China; Sichuan University Yibin Park, Yibin Institute of Industrial Technology, Yibin 644600, China.
| | - Song Liu
- College of Architecture and Environment, Sichuan University, Chengdu 610065, China; College of Carbon Neutrality Future Technology, Sichuan University, Chengdu 610065, China; Sichuan University Yibin Park, Yibin Institute of Industrial Technology, Yibin 644600, China
| | - Ruilin Wan
- College of Architecture and Environment, Sichuan University, Chengdu 610065, China; College of Carbon Neutrality Future Technology, Sichuan University, Chengdu 610065, China; Sichuan University Yibin Park, Yibin Institute of Industrial Technology, Yibin 644600, China
| | - Ning Wang
- College of Architecture and Environment, Sichuan University, Chengdu 610065, China; College of Carbon Neutrality Future Technology, Sichuan University, Chengdu 610065, China; Sichuan University Yibin Park, Yibin Institute of Industrial Technology, Yibin 644600, China
| | - Dongyang Chen
- College of Architecture and Environment, Sichuan University, Chengdu 610065, China; College of Carbon Neutrality Future Technology, Sichuan University, Chengdu 610065, China; Sichuan University Yibin Park, Yibin Institute of Industrial Technology, Yibin 644600, China
| | - Yi Li
- College of Architecture and Environment, Sichuan University, Chengdu 610065, China; College of Carbon Neutrality Future Technology, Sichuan University, Chengdu 610065, China; Sichuan University Yibin Park, Yibin Institute of Industrial Technology, Yibin 644600, China
| | - Yan Jiang
- Sichuan Ecological Environment Monitoring Center, Chengdu 610091, China
| | - Zhihan Rao
- College of Architecture and Environment, Sichuan University, Chengdu 610065, China; College of Carbon Neutrality Future Technology, Sichuan University, Chengdu 610065, China; Sichuan University Yibin Park, Yibin Institute of Industrial Technology, Yibin 644600, China; Sichuan Ecological Environment Monitoring Center, Chengdu 610091, China
| | - Wanting Jiang
- Chengdu Academy of Environmental Sciences, Chengdu 610072, China
| | - Danlin Song
- Chengdu Academy of Environmental Sciences, Chengdu 610072, China
| | - Qinwen Tan
- Chengdu Academy of Environmental Sciences, Chengdu 610072, China
| | - Fumo Yang
- College of Architecture and Environment, Sichuan University, Chengdu 610065, China; College of Carbon Neutrality Future Technology, Sichuan University, Chengdu 610065, China; Sichuan University Yibin Park, Yibin Institute of Industrial Technology, Yibin 644600, China
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13
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Gao P, Deng R, Jia S, Li Y, Wang X, Xing Q. Effects of combustion temperature on the optical properties of brown carbon from biomass burning. J Environ Sci (China) 2024; 137:302-309. [PMID: 37980017 DOI: 10.1016/j.jes.2022.12.026] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2022] [Revised: 11/27/2022] [Accepted: 12/21/2022] [Indexed: 11/20/2023]
Abstract
Biomass burning has been known as one of main sources of Brown Carbon (BrC) in atmosphere. In this study, by controlling the combustion temperature at 250°C, 350°C, and 450°C, the methanol soluble organic carbon (MSOC) and methanol insoluble carbon (MISC) from pine wood burning was collected by impinger. UV-Vis, excitation emission matrix (EEM), TEM and FTIR spectra were applied to investigate the properties of BrC collected. For MSOC at 250°C and 350°C, all the spectral profiles of UV-Vis absorption and excitation emission matrix are almost the same, while the EEM of MSOC at 450°C are different from that of the other two. For MISC fluorescence was observed only in the case of 450°C. In the FTIR spectra, with the temperature increasing the peaks associated to the oxygen-contained functions was weakened, indicating the formation of the fluorophores with larger conjugated system, especially aromatic hydrocarbons. Our results show that biomass combustion at low temperature produces more oxygen-riched BrC, which possesses relatively lower light absorption, while at high temperature produces more aromatics hydrocarbons with relatively strong light absorption. The results of this work are helpful to trace the source of brown carbon and optimize biomass energy utilization.
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Affiliation(s)
- Peng Gao
- School of Chemistry Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Rule Deng
- School of Chemistry Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Song Jia
- School of Chemistry Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yue Li
- School of Chemistry Sciences, University of Chinese Academy of Sciences, Beijing 100049, China
| | - Xuefei Wang
- School of Chemistry Sciences, University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Qian Xing
- College of Chemistry and Materials Engineering, Beijing Technology and Business University, Beijing 100048, China.
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14
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Cheng X, Yu J, Chen L, Sun Y, Zhang H, Gao S, Kong S, Zheng H, Wang H. Influence of pollution control measures on the reduction of black carbon in an urban site of megacity, Tianjin, China based on ground-monitored and MERRA-2 reanalysis data. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 912:169466. [PMID: 38145677 DOI: 10.1016/j.scitotenv.2023.169466] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 12/10/2023] [Accepted: 12/16/2023] [Indexed: 12/27/2023]
Abstract
The concentration of particulate matter (PM) has been reduced significantly with the implementation of air pollution control plans in Tianjin. However, as an important component of PM that can lead to global warming and adverse health effects, the influence of pollution control measures (PCM) on black carbon (BC) has been less studied. In this study, ten years of BC concentration satellite-based reanalysis data were collected from MERRA-2 (Modern-Era Retrospective Analysis for Research and Applications, Version 2), and their reliability was verified using ground-monitored BC data. Using the proposed Kolmogorov-Zurbenko and artificial neural network (KZ-ANN) model, the influences of meteorology and emission measures were separated. The results indicated that the overall meteorological conditions were not conducive to BC diffusion, especially in autumn and winter with low temperature, surface solar radiation, boundary layer height, and high atmospheric pressure, all of which increased the BC concentration. This study also found that although a significant reduction in BC emissions was observed in Tianjin (the total emissions of BC in 2020 dropped by 52 % compared with the level in 2013), the change in emission-influenced BC was relatively low (the concentration of emission-influenced BC in 2022 dropped by only 2.39 % compared to that in 2013). The reduction of emission-influenced BC concentration during the air pollution prevention control and action plan (APPC) was higher than the level during of the three-year action plan for winning the blue sky defense war (abbreviated as the Blue Sky Defense War). In addition, the lockdown measures during the Corona Virus Disease 2019 (COVID-19) did not have beneficial effect on the reduction of emission-influenced BC concentration. This phenomenon can be explained by the long-range transport of BC from surrounding areas, which was also proven by the results of the backward trajectory analysis. Therefore, efforts on emissions reduction in Tianjin were diminished. It is necessary to cooperate with the governments in surrounding areas to implement joint BC control measures, especially in autumn and winter.
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Affiliation(s)
- Xin Cheng
- School of Geographic and Environmental Sciences, Tianjin Normal University, Tianjin 300387, China
| | - Jie Yu
- School of Geographic and Environmental Sciences, Tianjin Normal University, Tianjin 300387, China
| | - Li Chen
- School of Geographic and Environmental Sciences, Tianjin Normal University, Tianjin 300387, China
| | - Yanling Sun
- School of Geographic and Environmental Sciences, Tianjin Normal University, Tianjin 300387, China
| | - Hui Zhang
- School of Geographic and Environmental Sciences, Tianjin Normal University, Tianjin 300387, China
| | - Shuang Gao
- School of Geographic and Environmental Sciences, Tianjin Normal University, Tianjin 300387, China.
| | - Shaofei Kong
- Department of Atmospheric Sciences, School of Environmental Studies, China University of Geosciences, Wuhan 430074, China.
| | - Huang Zheng
- Department of Atmospheric Sciences, School of Environmental Studies, China University of Geosciences, Wuhan 430074, China; Research Centre for Complex Air Pollution of Hubei Province, Wuhan 430078, China
| | - Hui Wang
- Tianjin Changhai Environmental Monitoring Service Corporation, Tianjin, China
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15
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Asutosh A, Vinoj V. Role of local absorbing aerosols in modulating Indian summer monsoon rainfall. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 910:168663. [PMID: 37981155 DOI: 10.1016/j.scitotenv.2023.168663] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2023] [Revised: 11/10/2023] [Accepted: 11/15/2023] [Indexed: 11/21/2023]
Abstract
Absorbing aerosols and their impact on the Indian monsoon system is highly complex and demands more scientific understanding. Our study using a chemistry-coupled regional climate model (RegCM 4.5) with idealized experiments observed that natural and anthropogenic absorbing aerosols (i.e., dust and carbonaceous aerosols) reduce monsoon precipitation in a seasonal time scale. More than 1 mm day-1 decline in mean summertime rainfall was observed over parts of the central Indian region and Indo-Gangetic plane for dust aerosol. A substantial reduction in the land-sea pressure gradient and lower tropospheric moisture distribution were found to control the observed modulation in rainfall. Near-surface wind circulation responded distinctly to natural (dust) and anthropogenic (carbonaceous) aerosols. The dust forcing weakened the monsoon trough by creating an anomalous anticyclonic circulation. The Northern Arabian Sea acted as a moisture source for the carbonaceous aerosol forcing. Intraseasonal rainfall over central India appeared to have a sharp reduction for dust forcing during early June, with a moderate increase for carbonaceous aerosols. Such quantification is essential for understanding the impact of aerosol forcing on regional climate change and the water cycle and has implications for emissions management and mitigation policies.
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Affiliation(s)
- A Asutosh
- School of Earth, Ocean, and Climate Sciences, Indian Institute of Technology Bhubaneswar, Bhubaneswar, Odisha 752 050, India; National Center for Atmospheric Research, Boulder, CO 80301, USA.
| | - V Vinoj
- School of Earth, Ocean, and Climate Sciences, Indian Institute of Technology Bhubaneswar, Bhubaneswar, Odisha 752 050, India
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16
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Targino AC, Krecl P, Oukawa GY, Mollinedo EM. A short climatology of black and brown carbon and their sources at a suburban site impacted by smoke in Brazil. J Environ Sci (China) 2024; 136:498-511. [PMID: 37923459 DOI: 10.1016/j.jes.2022.12.025] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2022] [Revised: 12/20/2022] [Accepted: 12/20/2022] [Indexed: 11/07/2023]
Abstract
Emissions from biomass burning challenge efforts to curb air pollution in cities downwind of fire-prone regions, as they contribute large amounts of brown carbon (BrC) and black carbon (BC) particles. We investigated the patterns of BrC and BC concentrations using Aethalometer data (at λ = 370 and 880 nm, respectively) spanning four years at a site impacted by the outflow of smoke. The data required to be post processed for the shadowing effect since, without correction, concentrations would be between 29% and 35% underestimated. The BrC concentrations were consistently higher than the BC concentrations, indicating the prevalence of aerosols from biomass burning. The results were supported by the Ångström coefficient (Å370/880), with values predominantly larger than 1 (mean ± standard deviation: 1.25 ± 0.31). Å370/880 values below 1 were more prevalent during the wet season, which suggests a contribution from fossil fuel combustion. We observed sharp BrC and BC seasonal signals, with mean minimum concentrations of 0.40 µg/m3 and 0.36 µg/m3, respectively, in the wet season, and mean maximum concentrations of 2.05 µg/m3 and 1.53 µg/m3 in the dry season. The largest concentrations were observed when northerly air masses moved over regions with a high density of fire spots. Local burning of residential solid waste and industrial combustion caused extreme BrC and BC concentrations under favourable wind directions. Although neither pollutant is included in any ambient air quality standards, our results suggest that transboundary smoke may hamper efforts to meet the World Health Organization guidelines for fine particles.
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Affiliation(s)
- Admir Créso Targino
- Graduate Program in Environmental Engineering, Federal University of Technology, Av. Pioneiros 3131, Londrina, PR 86036-370, Brazil.
| | - Patricia Krecl
- Graduate Program in Environmental Engineering, Federal University of Technology, Av. Pioneiros 3131, Londrina, PR 86036-370, Brazil
| | - Gabriel Yoshikazu Oukawa
- Department of Environmental Engineering, Federal University of Technology, Av. Pioneiros 3131, Londrina, PR 86036-370, Brazil
| | - Eva Maria Mollinedo
- Graduate Program in Environmental Engineering, Federal University of Technology, Av. Pioneiros 3131, Londrina, PR 86036-370, Brazil
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17
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Yang L, Huang RJ, Yuan W, Huang DD, Huang C. pH-Dependent Aqueous-Phase Brown Carbon Formation: Rate Constants and Implications for Solar Absorption and Atmospheric Photochemistry. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2024; 58:1236-1243. [PMID: 38169373 DOI: 10.1021/acs.est.3c07631] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
Aqueous-phase reactions of α-dicarbonyls with amines or ammonium have been identified as important sources of secondary brown carbon (BrC). However, the kinetics of BrC formation and the effects of pH are still not very clear. In this study, the kinetics of BrC formation by aqueous reactions of α-dicarbonyls (glyoxal and methylglyoxal) with ammonium, amino acids, or alkylamines in bulk solution at different pH values are investigated. Our results reveal pH-parameterized BrC production rate constants, kBrCII (m-1 [M]-2 s-1), based on the light absorption between 300 and 500 nm: log10(kBrCII) = (1.0 ± 0.1) × pH - (7.4 ± 1.0) for reactions with glyoxal and log10(kBrCII) = (1.0 ± 0.1) × pH - (6.3 ± 0.9) for reactions with methylglyoxal. The linear slopes closing to 1.0 indicate that BrC formation is governed by the nitrogen nucleophilic addition pathway. Consequently, the absorptivities of the produced BrC increase exponentially with the increase of pH. BrC from reactions with methylglyoxal at higher pH (≥6.5) exhibits optical properties comparable to BrC from biomass burning or coal combustion, categorized as the "weakly" absorbing BrC, while BrC from reactions with methylglyoxal at lower pH (<6.0) or reactions with glyoxal (pH 5.0-7.0) falls into the "very weakly" absorbing BrC. The pH-dependent BrC feature significantly affects the solar absorption ability of the produced BrC and thus the atmospheric photochemical processes, e.g., BrC produced at pH 7.0 absorbs 14-16 times more solar power compared to that at pH 5.0, which in turn could lead to a decrease of 1 order of magnitude in the photolysis rate constants of O3 and NO2.
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Affiliation(s)
- Lu Yang
- State Key Laboratory of Loess Science, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ru-Jin Huang
- State Key Laboratory of Loess Science, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China
- Institute of Global Environmental Change, Xi'an Jiaotong University, Xi'an 710049, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Wei Yuan
- State Key Laboratory of Loess Science, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China
| | - Dan Dan Huang
- State Environmental Protection Key Laboratory of Formation and Prevention of the Urban Air Pollution Complex, Shanghai Academy of Environmental Sciences, Shanghai 200233, China
| | - Cheng Huang
- State Environmental Protection Key Laboratory of Formation and Prevention of the Urban Air Pollution Complex, Shanghai Academy of Environmental Sciences, Shanghai 200233, China
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18
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Wu B, Wu Z, Yao Z, Shen X, Cao X. Refined mass absorption cross-section of black carbon from typical non-road mobile machinery in China based on real-world measurements. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 908:168579. [PMID: 37967631 DOI: 10.1016/j.scitotenv.2023.168579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2023] [Revised: 11/10/2023] [Accepted: 11/12/2023] [Indexed: 11/17/2023]
Abstract
Non-road mobile machinery (NRMM) is becoming a more prominent contribution of black carbon (BC), and mass absorption cross-section (MAC) as an essential parameter to characterize the BC optical property is still not clear. In this study, we explored the impacts of key factors on the MAC of BC based on real-world measurements from 41 typical NRMM. We characterized the organic carbon (OC) and elemental carbon (EC), and found MAC values of BC from NRMM increase as the OC/EC mass ratios increase, since the OC coating can enhance BC light absorption. With more stringent emission standards, the MAC values of all tested NRMM show a significant decreasing trend. Meanwhile, we found the absorption coefficients obtained by filter-based (bfilter) and in-situ-based (bin-situ) methods present good correlation for NRMM in this study, but bfilter are significantly higher than bin-situ when bfilter are above 40,000 Mm-1. Furthermore, we have refined the MAC values under different emission standards, and recommended a more appropriate MAC value (11.5 ± 3.4 m2/g) of NRMM at 550 nm wavelength, which is 1.5 times of the MAC value (7.5 m2/g) commonly used in previous studies. Our results will be indispensable for accurate BC quantification from NRMM and climate radiative effects prediction.
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Affiliation(s)
- Bobo Wu
- School of Ecology and Environment, Beijing Technology and Business University, Beijing 100048, China; State Environmental Protection Key Laboratory of Food Chain Pollution Control, Beijing Technology and Business University, Beijing 100048, China
| | - Zichun Wu
- School of Ecology and Environment, Beijing Technology and Business University, Beijing 100048, China
| | - Zhiliang Yao
- School of Ecology and Environment, Beijing Technology and Business University, Beijing 100048, China; State Environmental Protection Key Laboratory of Food Chain Pollution Control, Beijing Technology and Business University, Beijing 100048, China.
| | - Xianbao Shen
- School of Ecology and Environment, Beijing Technology and Business University, Beijing 100048, China; State Environmental Protection Key Laboratory of Food Chain Pollution Control, Beijing Technology and Business University, Beijing 100048, China
| | - Xinyue Cao
- School of Ecology and Environment, Beijing Technology and Business University, Beijing 100048, China; State Environmental Protection Key Laboratory of Food Chain Pollution Control, Beijing Technology and Business University, Beijing 100048, China
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Liu S, Wang H, Zhao D, Ke Y, Wu Z, Shen L, Zhao T. Aircraft observations of aerosols and BC in autumn over Guangxi Province, China: Diurnal variation, vertical distribution and source appointment. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 906:167550. [PMID: 37802359 DOI: 10.1016/j.scitotenv.2023.167550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 09/20/2023] [Accepted: 09/30/2023] [Indexed: 10/10/2023]
Abstract
To understand the vertical distribution characteristics of aerosols and black carbon (BC) in southwest China, 12 sorties were conducted from October 10 to November 3, 2020, and the vertical profiles of aerosols and BC at different times in Nanning, Guangxi Province, in autumn were obtained. The contents of aerosols (Na <100 cm-3) and BC (MBC <0.11 μg∙m-3) at 2000-6000 m were small and did not change with height. The vertical profiles of Na and MBC below 2000 m were affected by the boundary layer (PBL), and the vertical profiles had obvious diurnal variations. Aerosols and BC in the residual layer (RL) entered PBL at 10:00-12:00, resulting in increased the values of Na (1971 cm-3) and MBC (2.93 μg∙m-3) in PBL. Under intense turbulent activity in PBL from 13:00 to 15:00, Na and MBC changed little with height. At 17:00, PBL height dropped, aerosols and BC remained in RL. From 18:00 to 22:00, the PBL height decreased, and the aerosols and BC were trapped below 200 m. BC below 2000 m was mainly from fossil fuel combustion. Between 2000 m and 6000 m, MBCff > MBCbb at 12:00-17:00, and MBCbb was similar to MBCff at 10:00, 18:00 and 22:00. The air masses passing over Southeast Asian countries and Guangdong Province brought more BC to Guangxi Province. Air masses from different sources had different effects on aerosols in Guangxi Province. Below 3000 m, the value of Na under the influence of land air mass was greater than that under the influence of ocean air mass. Above 3000 m, different sources of air mass mainly affected the aerosol number concentration spectrum. Under the influence of ocean air mass, the number and concentration of aerosol with particle size of 0.11 μm and 0.24 μm had increased in Guangxi Province.
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Affiliation(s)
- Sihan Liu
- China Meteorological Administration Aerosol-Cloud and Precipitation Key Laboratory, Nanjing University of Information Science and Technology, Nanjing 210044, China
| | - Honglei Wang
- China Meteorological Administration Aerosol-Cloud and Precipitation Key Laboratory, Nanjing University of Information Science and Technology, Nanjing 210044, China.
| | - Delong Zhao
- Beijing Weather Modification Office, Beijing 100089, China
| | - Yue Ke
- China Meteorological Administration Aerosol-Cloud and Precipitation Key Laboratory, Nanjing University of Information Science and Technology, Nanjing 210044, China
| | - Zihao Wu
- China Meteorological Administration Aerosol-Cloud and Precipitation Key Laboratory, Nanjing University of Information Science and Technology, Nanjing 210044, China
| | - Lijuan Shen
- School of Atmosphere and Remote Sensing, Wuxi University, Wuxi 214105, China
| | - Tianliang Zhao
- China Meteorological Administration Aerosol-Cloud and Precipitation Key Laboratory, Nanjing University of Information Science and Technology, Nanjing 210044, China
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20
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Forello AC, Cunha-Lopes I, Almeida SM, Alves CA, Tchepel O, Crova F, Vecchi R. Insights on the combination of off-line and on-line measurement approaches for source apportionment studies. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 900:165860. [PMID: 37516189 DOI: 10.1016/j.scitotenv.2023.165860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Revised: 06/28/2023] [Accepted: 07/26/2023] [Indexed: 07/31/2023]
Abstract
This paper presents a source apportionment study performed on a dataset collected at a trafficked site in Coimbra (Portugal) during the period December 2018-June 2019. The novelty of this work consists in the methodological approach used and the sensitivity study carried out to give hints to potential future applications. Indeed, a multi-time resolution and multi-parameter study was performed joining together aerosol data from 24-h chemically characterized samples and high-time resolution multi-wavelength absorption coefficients retrieved by an Aethalometer. A detailed sensitivity study on the most suitable combination of time resolution and uncertainties was carried out to obtain reliable physical and stable solutions over all analyses. In parallel, a regular EPA-PMF source apportionment study using chemical and optical variables averaged on 24 h is presented and discussed in comparison to the more complex multi-time and multi-parameter approach. Apart from results pertaining to the identification and relevance of different sources in Coimbra, the methodological results shown here can give guidance for readers who want to implement optical variables jointly with chemical ones in the same model run.
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Affiliation(s)
- Alice C Forello
- Department of Physics, Università degli Studi di Milano, Milan 20133, Italy; National Institute of Nuclear Physics INFN-Milan, Milan 20133, Italy
| | - Inés Cunha-Lopes
- Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, 2695-066 Bobadela-LRS, Portugal
| | - Susana M Almeida
- Centro de Ciências e Tecnologias Nucleares, Instituto Superior Técnico, Universidade de Lisboa, 2695-066 Bobadela-LRS, Portugal
| | - Célia A Alves
- Centre of Environmental and Marine Studies, Department of Environment, University of Aveiro, 3810-193 Aveiro, Portugal
| | - Oxana Tchepel
- CITTA, Faculty of Sciences and Technology, University of Coimbra, 3004-531 Coimbra, Portugal
| | - Federica Crova
- Department of Physics, Università degli Studi di Milano, Milan 20133, Italy; National Institute of Nuclear Physics INFN-Milan, Milan 20133, Italy
| | - Roberta Vecchi
- Department of Physics, Università degli Studi di Milano, Milan 20133, Italy; National Institute of Nuclear Physics INFN-Milan, Milan 20133, Italy.
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21
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Logesh B, Karthik V, Bhaskar BV, Ebenezer E, Kumar MA. Implications of equivalent black carbon heterogeneity in south Indian high-altitude eco-sensitive region. ENVIRONMENTAL MONITORING AND ASSESSMENT 2023; 195:1374. [PMID: 37880449 DOI: 10.1007/s10661-023-11957-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Accepted: 10/05/2023] [Indexed: 10/27/2023]
Abstract
Large-scale representative source apportionment studies are uncommon, undermining source contribution studies in India, particularly in high-altitude locations. Kodaikanal is a high-altitude region in India's Western Ghats, with spatial heterogeneity of sources altering chemical complexity; thus, the associated implications are unknown. We conducted the campaign study REBER (Research on Equivalent Black Carbon Monitoring in an Eco-sensitive Region) at three Kodaikanal sites to understand local point sources, characteristics, and distribution of eBC during the winter-to-summer monsoon transition. For two main reasons: to understand the seasonal change of BC since the transition period has the lowest wind speeds and the highest particulate concentrations and is prone to high pollution events most often during seasonal transition months, and to study local pollution since the meridional monsoon and zonal winds in study region weaken whereby the transport of pollutants from ocean to land and vice versa is minimal. The results showed that the eBC mass concentration was 85% higher than in the previous study conducted by Bhaskar et al. (2018) during the monsoon transition period. To determine the ratio of fossil fuel and wood-burning sources, a real-time apportionment model of atmospheric eBC is used. The percentage of wood burning in the background location ranges from 21.12 to 88.98%. Wood burning leads in residential sites with 57.5 ± 7.3%, whereas fossil fuel contribution dominates traffic sites with 69.84 ± 10.2%. Fossil fuel contributions are significant in different characteristics of environments, ranging from 42.5 to 69.84%. The results of the conditional bivariate probability function (CBPF) analysis pointed out a competition between anthropogenic and natural sources to contribute as local sources to the monitoring stations. A scanning electron microscope (SEM) paired with an energy dispersive X-ray (EDX) analysis found that the particle size was 93% relatively large compared to other hill stations in India. The variation in the chemical constituents indicates that the particles originated from various sources.
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Affiliation(s)
- B Logesh
- Department of Bioenergy, School of Energy, Environment and Natural Resources, Madurai Kamaraj University, Madurai, 625021, India
| | - V Karthik
- Department of Bioenergy, School of Energy, Environment and Natural Resources, Madurai Kamaraj University, Madurai, 625021, India
| | - B Vijay Bhaskar
- Department of Bioenergy, School of Energy, Environment and Natural Resources, Madurai Kamaraj University, Madurai, 625021, India.
| | - E Ebenezer
- Kodaikanal Solar Observatory, Indian Institute of Astrophysics, Kodaikanal, Dindigul, India
| | - M Arun Kumar
- Advanced Environmental Laboratory, Tamil Nadu Pollution Control Board, Coimbatore, 641114, India
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22
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Targino AC, Moreno FL, Krecl P, Cardoso JV. Significant differences in black and brown carbon concentrations at urban and suburban sites. Heliyon 2023; 9:e18418. [PMID: 37520949 PMCID: PMC10374922 DOI: 10.1016/j.heliyon.2023.e18418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2023] [Revised: 07/16/2023] [Accepted: 07/17/2023] [Indexed: 08/01/2023] Open
Abstract
Light-absorbing carbonaceous particles (LAC) may cause and/or exacerbate non-communicable diseases, interfere with the Earth's radiative balance, darken urban buildings and impair vistas. In this study, we explored the temporal behaviour of LAC concentrations measured at wavelengths of 370 nm (brown carbon, BrC) and 880 nm (black carbon, BC) at two sites of a mid-sized city in Brazil. We observed sharp changes in LAC concentrations at the city centre site in response to variations in traffic volume. The highest concentrations were observed when winds originated from both the city core and from the direction of the bus terminal. The suburban site exhibited a notably uniform diurnal pattern and consistently lower LAC concentrations throughout the day. Nevertheless, substantial increases during the evening led to mean BrC and BC concentrations (2.6 and 2.2 μg m-3, respectively) comparable to daytime peaks observed in the city centre (3 μg m-3 and 2.5 μg m-3). This phenomenon was attributed to the burning of residential waste and overgrown vegetation in nearby vacant lots. Moreover, the highest concentrations coincided with periods of low wind speeds, usually linked to non-buoyant plumes from point sources. BrC concentrations surpassed BC concentrations, even at the city centre site. Not only was the Ångström absorption exponent (Å370/880) larger at the suburban site compared to the city centre (95th percentiles of 1.73 and 1.38, respectively), but it also exhibited a wider span. Overall, the combined LAC and Å370/880 data indicated that i) biomass burning is a major source of LAC at the suburban site; ii) at the city centre, bare BC particles may become internally mixed with BrC from biomass or fossil fuel emissions and enhance absorption at lower wavelengths. The occurrence of LAC peaks outside the evening rush hours suggests that other sources but on-road vehicular emissions may contribute to the deterioration of the air quality in the urban core. Tackling air quality across the urban perimeter requires targeting other potential sources but traffic emissions.
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Dehhaghi S, Bahiraee H, Pardakhti A, Rashidi Y. Traces of black carbon sources before and after the Covid-19 outbreak in Tehran, Iran. ENVIRONMENTAL MONITORING AND ASSESSMENT 2023; 195:853. [PMID: 37326877 DOI: 10.1007/s10661-023-11442-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Accepted: 06/01/2023] [Indexed: 06/17/2023]
Abstract
The concentration of black carbon was measured in four sites of the industrial and high-traffic metropolis of Tehran with different land uses. Then, the contribution of biomass and fossil fuels in the emission of this pollutant was modeled using the Aethalometer model. The possible locations of important sources of black carbon dissemination were projected using PSCF and CWT models, and the results were compared in the two periods before and after the Covid-19 outbreak. Temporal variations of black carbon illustrated that BC concentration decreased in the period after the onset of the pandemic in all studied areas, and this decline was more explicit in the traffic intersection of the city. Diurnal changes of BC concentration indicated the significant impact of the application of the law banning night traffic of motor vehicles in reducing the BC concentration in this period, and probably the reduction of HDDV traffic has played the most important role in this reduction. The results related to the share of BC sources indicated that black carbon emissions are affected by an average of about 80% of fossil fuel combustion and wood combustion interferes with about 20% of BC emissions. Finally, speculations were made about the possible sources of BC emission and its urban scale transport using PSCF and CWT models, which indicated the superiority of the CWT model in terms of source segregation. The results of this analysis were further utilized to surmise black carbon emission sources based on the land use of receptor points.
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Affiliation(s)
- Sam Dehhaghi
- Environmental Sciences Research Institute, Shahid Beheshti University, Tehran, Iran.
| | - Hossein Bahiraee
- Environmental Sciences Research Institute, Shahid Beheshti University, Tehran, Iran
| | | | - Yousef Rashidi
- Environmental Sciences Research Institute, Shahid Beheshti University, Tehran, Iran
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24
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Feng W, Shao Z, Wang Q, Xie M. Size-resolved light-absorbing organic carbon and organic molecular markers in Nanjing, east China: Seasonal variations and sources. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023:122006. [PMID: 37302787 DOI: 10.1016/j.envpol.2023.122006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 06/07/2023] [Accepted: 06/08/2023] [Indexed: 06/13/2023]
Abstract
Owing to the potential influence of light-absorbing organic carbon (OC), also termed "brown carbon" (BrC), on the planetary radiation budget, many studies have focused on its absorption in single-sized ranges of particulate matter (PM). However, the size distribution and organic tracer-based source apportionment of BrC absorption have not been extensively investigated. In this study, size-resolved PM samples were collected using multi-stage impactors from eastern Nanjing during each season in 2017. The light absorption of methanol-extractable OC at 365 nm (Abs365, Mm-1) was determined using spectrophotometry, and a series of organic molecular markers (OMMs) was measured using a gas chromatography-mass spectrometer. Fine PM with an aerodynamic diameter <2.1 μm (PM2.1) dominated Abs365 (79.8 ± 10.4%) of the total size ranges with maxima and minima in winter and summer, respectively. The distributions of Abs365 shifted to larger PM sizes from winter to spring and summer due to lower primary emissions and increased BrC chromophores in dust. Except for low-volatility (po,*L < 10-10 atm) polycyclic aromatic hydrocarbons (PAHs), the non-polar OMMs, including n-alkanes, PAHs, oxygenated PAHs, and steranes, showed a bimodal distribution pattern. Secondary products of biogenic precursors and biomass burning tracers presented a unimodal distribution peaking at 0.4-0.7 μm, while sugar alcohols and saccharides were enriched in coarse PM. Their seasonal variations in average concentrations reflected intense photochemical reactions in summer, more biomass burning emissions in winter, and stronger microbial activity in spring and summer. Positive matrix factorization was used for the source apportionment of Abs365 in fine and coarse PM samples. Biomass burning contributed an average of 53.9% to the Abs365 of PM2.1 extracts. The Abs365 of coarse PM extracts was associated with various dust-related sources where the aging processes of aerosol organics could occur.
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Affiliation(s)
- Wei Feng
- Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, School of Environmental Science and Engineering, Nanjing University of Information Science & Technology, 219 Ningliu Road, Nanjing, 210044, China
| | - Zhijuan Shao
- School of Environment Science and Engineering, Suzhou University of Science and Technology ShiHu Campus, 99 Xuefu Road, Suzhou, 215009, China
| | - Qin'geng Wang
- State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China
| | - Mingjie Xie
- Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, School of Environmental Science and Engineering, Nanjing University of Information Science & Technology, 219 Ningliu Road, Nanjing, 210044, China.
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25
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Gupta P, Jangid A, Kumar R. COVID-19-associated 2020 lockdown: a study on atmospheric black carbon fall impact on human health. ENVIRONMENTAL GEOCHEMISTRY AND HEALTH 2023; 45:3507-3520. [PMID: 36367602 PMCID: PMC9650661 DOI: 10.1007/s10653-022-01430-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/10/2022] [Accepted: 10/25/2022] [Indexed: 06/01/2023]
Abstract
The mean mass concentrations of black carbon (BC), biomass burning (BC)bb, and fossil fuel combustion (BC)ff have been estimated during March-May 2020 (during the COVID-19 outbreak) and March-May 2019 at a semiarid region of Agra over the Indo-Gangetic basin region. The daily mean mass concentration of BC in 2020 and 2019 was 3.9 and 6.9 µg m-3, respectively. The high monthly mean mass concentration of BC was found to be 4.7, 3.4 and 3.3 µg m-3 in Mar-2020, Apr-2020, and May-2020, respectively, whereas in Mar-2019, Apr-2019, and May-2019 was 7.7, 7.5 and 5.4 µg m-3, respectively. The absorption coefficient (babs) and absorption angstrom exponent (AAE) of black carbon were calculated. The highest mean AAE was 1.6 in the year 2020 (Mar-May 2020) indicating the dominance of biomass burning. The mean mass concentration of fossil fuel (BC)ff and biomass burning (BC)bb is 3.4 and 0.51 µg m-3, respectively, in 2020 whereas 6.4 and 0.73 µg m-3, respectively, in 2019. The mean fraction contribution of BC with fossil fuel (BC)ff was 82.1 ± 13.5% and biomass burning (BC)bb was 17.9 ± 4.3% in 2020, while in 2019, fossil fuel (BC)ff was 86.7 ± 13.5% and biomass burning (BC)bb was 13.3 ± 6.7%. The population-weighted mean concentration of BC, fossil fuel (BC)ff, and biomass burning (BC)bb has been calculated. The health risk assessment of BC has been analyzed in the form of attributable relative risk factors and attributed relative risk during the COVID-19 outbreak using AirQ + v.2.0 model. The attributable relative risk factors of BC were 20.6% in 2020 and 29.4% in 2019. The mean attributed relative risk per 10,000,000 populations at 95% confidence interval (CI) due to BC was 184.06 (142.6-225.2) in 2020 and 609.06 (418.3-714.6) in 2019. The low attributed factor and attributed relative risk in 2020 may be attributed to improvements in air quality and a fall in the emission of BC. In 2020, due to the COVID-19 pandemic, the whole country faced the biggest lockdown, ban of the transportation of private vehicles, trains, aircraft, and construction activities, and shut down of the industry leading to a fall in the impact of BC on human health. Overall, this was like a blessing in disguise. This study will help in future planning of mitigation and emission control of air pollutants in large and BC in particular. It only needs a multipronged approach. This study may be like torch bearing to set path for mitigation of impacts of air pollution and improvement of air quality.
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Affiliation(s)
- Pratima Gupta
- Department of Chemistry, Faculty of Science, Dayalbagh Educational Institute (Deemed University), Dayalbagh, Agra-5, India.
| | - Ashok Jangid
- Department of Physics and Computer Science, Faculty of Science, Dayalbagh Educational Institute (Deemed University), Dayalbagh, Agra-5, India
| | - Ranjit Kumar
- Department of Chemistry, Faculty of Science, Dayalbagh Educational Institute (Deemed University), Dayalbagh, Agra-5, India
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26
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Lepistö T, Barreira LMF, Helin A, Niemi JV, Kuittinen N, Lintusaari H, Silvonen V, Markkula L, Manninen HE, Timonen H, Jalava P, Saarikoski S, Rönkkö T. Snapshots of wintertime urban aerosol characteristics: Local sources emphasized in ultrafine particle number and lung deposited surface area. ENVIRONMENTAL RESEARCH 2023; 231:116068. [PMID: 37149021 DOI: 10.1016/j.envres.2023.116068] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 04/14/2023] [Accepted: 05/04/2023] [Indexed: 05/08/2023]
Abstract
Urban air fine particles are a major health-relating problem. However, it is not well understood how the health-relevant features of fine particles should be monitored. Limitations of PM2.5 (mass concentration of sub 2.5 μm particles), which is commonly used in the health effect estimations, have been recognized and, e.g., World Health Organization (WHO) has released good practice statements for particle number (PN) and black carbon (BC) concentrations (2021). In this study, a characterization of urban wintertime aerosol was done in three environments: a detached housing area with residential wood combustion, traffic-influenced streets in a city centre and near an airport. The particle characteristics varied significantly between the locations, resulting different average particle sizes causing lung deposited surface area (LDSA). Near the airport, departing planes had a major contribution on PN, and most particles were smaller than 10 nm, similarly as in the city centre. The high hourly mean PN (>20 000 1/cm3) stated in the WHO's good practices was clearly exceeded near the airport and in the city centre, even though traffic rates were reduced due to a SARS-CoV-2-related partial lockdown. In the residential area, wood combustion increased both BC and PM2.5, but also PN of sub 10 and 23 nm particles. The high concentrations of sub 10 nm particles in all the locations show the importance of the chosen lower size limit of PN measurement, e.g., WHO states that the lower limit should be 10 nm or smaller. Furthermore, due to ultrafine particle emissions, LDSA per unit PM2.5 was 1.4 and 2.4 times higher near the airport than in the city centre and the residential area, respectively, indicating that health effects of PM2.5 depend on urban environment as well as conditions, and emphasizing the importance of PN monitoring in terms of health effects related to local pollution sources.
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Affiliation(s)
- Teemu Lepistö
- Aerosol Physics Laboratory, Physics Unit, Faculty of Engineering and Natural Sciences, Tampere University, Tampere, 33014, Finland.
| | - Luis M F Barreira
- Atmospheric Composition Research, Finnish Meteorological Institute, Helsinki, 00101, Finland
| | - Aku Helin
- Atmospheric Composition Research, Finnish Meteorological Institute, Helsinki, 00101, Finland
| | - Jarkko V Niemi
- Helsinki Region Environmental Services Authority HSY, Helsinki, 00066, Finland
| | - Niina Kuittinen
- Aerosol Physics Laboratory, Physics Unit, Faculty of Engineering and Natural Sciences, Tampere University, Tampere, 33014, Finland
| | - Henna Lintusaari
- Aerosol Physics Laboratory, Physics Unit, Faculty of Engineering and Natural Sciences, Tampere University, Tampere, 33014, Finland
| | - Ville Silvonen
- Aerosol Physics Laboratory, Physics Unit, Faculty of Engineering and Natural Sciences, Tampere University, Tampere, 33014, Finland
| | - Lassi Markkula
- Aerosol Physics Laboratory, Physics Unit, Faculty of Engineering and Natural Sciences, Tampere University, Tampere, 33014, Finland
| | - Hanna E Manninen
- Helsinki Region Environmental Services Authority HSY, Helsinki, 00066, Finland
| | - Hilkka Timonen
- Atmospheric Composition Research, Finnish Meteorological Institute, Helsinki, 00101, Finland
| | - Pasi Jalava
- Inhalation Toxicology Laboratory, Department of Environmental and Biological Sciences, University of Eastern Finland, Kuopio, 70211, Finland
| | - Sanna Saarikoski
- Atmospheric Composition Research, Finnish Meteorological Institute, Helsinki, 00101, Finland
| | - Topi Rönkkö
- Aerosol Physics Laboratory, Physics Unit, Faculty of Engineering and Natural Sciences, Tampere University, Tampere, 33014, Finland
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Roy S, Habib G, Dev R, Joshi S, Qadri AM, Gupta T, Raman RS. Wintertime aerosol properties of urban desert region of western India: Implications in regional climate assessment. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 868:161473. [PMID: 36646216 DOI: 10.1016/j.scitotenv.2023.161473] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Revised: 01/04/2023] [Accepted: 01/04/2023] [Indexed: 06/17/2023]
Abstract
This study assessed the inter-relation between physiochemical and optical characteristics of aerosols measured at a desert-urban region affected by anthropogenic sources and desert dust during October 2020 to January 2021. Based on horizontal visibility and measured PM2.5 concentration, clear (37 %), light (33 %) and high (31 %) pollution periods were identified. Elemental and organic carbon (50 ± 15 μgm-3; 31 %) and secondary inorganics (53 ± 21 μgm-3; 33 %) dominated the PM2.5 mass (160 ± 4 μgm-3) during high pollution period with low dust (14 ± 7 μgm-3; 8 %) content. Interestingly, the clear pollution period was also influenced by carbonaceous fraction (19 ± 8 μgm-3; 32 %) and secondary inorganics (19 ± 5 μgm-3; 32 %), but the PM2.5 concentrations (59 ± 9 μgm-3) were ∼ one-third as compared to high pollution period. High scattering coefficients were observed which were comparable to highly polluted Indian city like Delhi. An exponential increase in non-absorbing material was observed and showed clear influence on light absorption capacity of EC and dust due to coating/mixing. High absorption Ångström exponent (AAE) >0.6 was observed for the ratio of non-absorbing to light absorbing components (LAC) in the range of 1-2.5 and EC/PM2.5 fraction of 7-14 %. While further increase in non-absorbing to absorbing components ratio > 4 and low amount of EC (<4 %) tend to decrease AAE below 0.4. Higher mass absorption cross-section (>30 m2g-1 of EC) was observed when 4-10 % EC fraction of PM2.5 associated with 1.5-3.5 times non-absorbing components to total absorbing components. Likewise, absorption enhanced by three to five folds compared to uncoated EC for low EC fraction (3-6 %) in PM2.5, but high non-absorbing to absorbing component ratio (>2.5). Interestingly, absorption was minimally amplified for nominal coating fraction associated with significant core materials or vice-versa. These findings have implications not only in regional climate assessment but also for other regions with comparable geography and source-mixes.
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Affiliation(s)
- Sayantee Roy
- Department of Civil Engineering, Indian Institute of Technology Delhi, New Delhi 110 016, India
| | - Gazala Habib
- Department of Civil Engineering, Indian Institute of Technology Delhi, New Delhi 110 016, India.
| | - Rishabh Dev
- Department of Civil Engineering, Indian Institute of Technology Delhi, New Delhi 110 016, India
| | - Swati Joshi
- Department of Civil Engineering, Indian Institute of Technology Delhi, New Delhi 110 016, India
| | - Adnan Mateen Qadri
- Department of Civil Engineering, Indian Institute of Technology Kanpur, Kanpur 208 016, India
| | - Tarun Gupta
- Department of Civil Engineering, Indian Institute of Technology Kanpur, Kanpur 208 016, India; Department of Civil Engineering, APTL at Centre for Environmental Science and Engineering (CESE), Indian Institute of Technology Kanpur, Kanpur 208 016, India
| | - Ramya Sunder Raman
- Department of Earth and Environmental Sciences, Indian Institute of Science Education and Research Bhopal, Bhopal Bypass Road, Bhauri, Bhopal 462 066, Madhya Pradesh, India; Center for Research on Environment and Sustainable Technologies, Indian Institute of Science Education and Research Bhopal, Bhopal Bypass Road, Bhauri, Bhopal 462 066, Madhya Pradesh, India
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Leskinen J, Hartikainen A, Väätäinen S, Ihalainen M, Virkkula A, Mesceriakovas A, Tiitta P, Miettinen M, Lamberg H, Czech H, Yli-Pirilä P, Tissari J, Jakobi G, Zimmermann R, Sippula O. Photochemical Aging Induces Changes in the Effective Densities, Morphologies, and Optical Properties of Combustion Aerosol Particles. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:5137-5148. [PMID: 36944040 PMCID: PMC10077587 DOI: 10.1021/acs.est.2c04151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/09/2022] [Revised: 02/10/2023] [Accepted: 03/07/2023] [Indexed: 06/18/2023]
Abstract
Effective density (ρeff) is an important property describing particle transportation in the atmosphere and in the human respiratory tract. In this study, the particle size dependency of ρeff was determined for fresh and photochemically aged particles from residential combustion of wood logs and brown coal, as well as from an aerosol standard (CAST) burner. ρeff increased considerably due to photochemical aging, especially for soot agglomerates larger than 100 nm in mobility diameter. The increase depends on the presence of condensable vapors and agglomerate size and can be explained by collapsing of chain-like agglomerates and filling of their voids and formation of secondary coating. The measured and modeled particle optical properties suggest that while light absorption, scattering, and the single-scattering albedo of soot particle increase during photochemical processing, their radiative forcing remains positive until the amount of nonabsorbing coating exceeds approximately 90% of the particle mass.
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Affiliation(s)
- Jani Leskinen
- Department
of Environmental and Biological Sciences, University of Eastern Finland, Kuopio FI 70211, Finland
| | - Anni Hartikainen
- Department
of Environmental and Biological Sciences, University of Eastern Finland, Kuopio FI 70211, Finland
| | - Sampsa Väätäinen
- Department
of Environmental and Biological Sciences, University of Eastern Finland, Kuopio FI 70211, Finland
| | - Mika Ihalainen
- Department
of Environmental and Biological Sciences, University of Eastern Finland, Kuopio FI 70211, Finland
| | - Aki Virkkula
- Atmospheric
Composition Research, Finnish Meteorological
Institute, Helsinki FI-00560, Finland
| | - Arunas Mesceriakovas
- Department
of Environmental and Biological Sciences, University of Eastern Finland, Kuopio FI 70211, Finland
| | - Petri Tiitta
- Department
of Environmental and Biological Sciences, University of Eastern Finland, Kuopio FI 70211, Finland
- Finnish
Meteorological Institute, Atmospheric Research
Centre of Eastern Finland, P.O. Box 1627, Kuopio 70211, Finland
| | - Mirella Miettinen
- Department
of Environmental and Biological Sciences, University of Eastern Finland, Kuopio FI 70211, Finland
| | - Heikki Lamberg
- Department
of Environmental and Biological Sciences, University of Eastern Finland, Kuopio FI 70211, Finland
| | - Hendryk Czech
- Joint
Mass Spectrometry Centre, University of Rostock, 18059 Rostock, Germany
and Cooperation Group Comprehensive Molecular Analytics, Helmholtz Zentrum München, München 81379, Germany
| | - Pasi Yli-Pirilä
- Department
of Environmental and Biological Sciences, University of Eastern Finland, Kuopio FI 70211, Finland
| | - Jarkko Tissari
- Department
of Environmental and Biological Sciences, University of Eastern Finland, Kuopio FI 70211, Finland
| | - Gert Jakobi
- Joint
Mass Spectrometry Centre, University of Rostock, 18059 Rostock, Germany
and Cooperation Group Comprehensive Molecular Analytics, Helmholtz Zentrum München, München 81379, Germany
| | - Ralf Zimmermann
- Joint
Mass Spectrometry Centre, University of Rostock, 18059 Rostock, Germany
and Cooperation Group Comprehensive Molecular Analytics, Helmholtz Zentrum München, München 81379, Germany
| | - Olli Sippula
- Department
of Environmental and Biological Sciences, University of Eastern Finland, Kuopio FI 70211, Finland
- Department
of Chemistry, University of Eastern Finland, Joensuu 80101, Finland
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29
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Long RW, Urbanski SP, Lincoln E, Colón M, Kaushik S, Krug JD, Vanderpool RW, Landis MS. Summary of PM 2.5 measurement artifacts associated with the Teledyne T640 PM Mass Monitor under controlled chamber experimental conditions using polydisperse ammonium sulfate aerosols and biomass smoke. JOURNAL OF THE AIR & WASTE MANAGEMENT ASSOCIATION (1995) 2023; 73:295-312. [PMID: 36716322 PMCID: PMC10112149 DOI: 10.1080/10962247.2023.2171156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 12/20/2022] [Accepted: 01/10/2023] [Indexed: 05/18/2023]
Abstract
Particulate matter (PM) is a major primary pollutant emitted during wildland fires that has the potential to pose significant health risks to individuals/communities who live and work in areas impacted by smoke events. Limiting exposure is the principle measure available to mitigate health impacts of smoke and therefore the accurate determination of ambient PM concentrations during wildland fire events is critical to protecting public health. However, monitoring air pollutants in smoke impacted environments has proven challenging in that measurement interferences or sampling conditions can result in both positive and negative artifacts. The EPA has performed research on methods for the measurement of PM2.5 in a series of laboratory-based studies including evaluation in smoke. This manuscript will summarize the results of the laboratory-based evaluation of federal equivalent method (FEM) monitors for PM2.5 with particular attention being given to the Teledyne-API Model T640 PM Mass monitor, as compared to the filter-based federal reference method (FRM). The T640 is an optical-based PM monitor and has been gaining wide use by state and local agencies in monitoring for PM2.5 U.S. National Ambient Air Quality Standards (NAAQS) attainment. At present, the T640 (includes both T640 and T640×) comprises ~44% of the PM2.5 FEM monitors in U.S. regulatory monitoring networks. In addition, the T640 has increasingly been employed for the higher time resolution comparison/evaluation of low-cost PM sensors including during smoke impacted events. Results from controlled non-smoke laboratory studies using generated ammonium sulfate aerosols demonstrated a generally negative T640 measurement artifact that was significantly related to the PM2.5 concentration and particle size distribution. Results from biomass burning chamber studies demonstrated positive and negative artifacts significantly associated with PM2.5 concentration and optical wavelength-dependent absorption properties of the smoke aerosol.Implications: The results detailed in this paper will provide state and local air monitoring agencies with the tools and knowledge to address PM2.5 measurement challenges in areas frequently impacted by wildland fire smoke. The observed large positive and negative artifacts in the T640 PM mass determination have the potential to result in false exceedances of the PM2.5 NAAQS or in the disqualification of monitoring data through an exceptional event designation. In addition, the observed artifacts in smoke impacted air will have a detrimental effect on providing reliable public information when wildfires occur and also in identifying reference measurements for small sensor evaluation studies. Other PM2.5 FEMs such as the BAM-1022 perform better in smoke and are comparable to the filter-based FRM. Care must be taken in choosing high time resolution FEM monitors that will be operated at smoke impacted sites. Accurate methods, such as the FRM and BAM-1022 will reduce the burden of developing and reviewing exceptional event request packages, data loss/disqualification, and provide states with tools to adequately evaluate public exposure risks and provide accurate public health messaging during wildfire/smoke events.
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Affiliation(s)
- Russell W. Long
- United States Environmental Protection Agency, Office of Research and Development, Research Triangle Park, North Carolina, United States of America
| | - Shawn P. Urbanski
- United States Forest Service, Rocky Mountain Research Station, Missoula, Montana, United States of America
| | - Emily Lincoln
- United States Forest Service, Rocky Mountain Research Station, Missoula, Montana, United States of America
| | - Maribel Colón
- United States Environmental Protection Agency, Office of Research and Development, Research Triangle Park, North Carolina, United States of America
| | - Surender Kaushik
- United States Environmental Protection Agency, Office of Research and Development, Research Triangle Park, North Carolina, United States of America
| | - Jonathan D. Krug
- United States Environmental Protection Agency, Office of Research and Development, Research Triangle Park, North Carolina, United States of America
| | - Robert W. Vanderpool
- United States Environmental Protection Agency, Office of Research and Development, Research Triangle Park, North Carolina, United States of America
| | - Matthew S. Landis
- United States Environmental Protection Agency, Office of Research and Development, Research Triangle Park, North Carolina, United States of America
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30
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Ho CS, Lv Z, Peng J, Zhang J, Choe TH, Zhang Q, Du Z, Mao H. Optical properties of vehicular brown carbon emissions: Road tunnel and chassis dynamometer tests. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 320:121037. [PMID: 36641064 DOI: 10.1016/j.envpol.2023.121037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Revised: 01/04/2023] [Accepted: 01/06/2023] [Indexed: 06/17/2023]
Abstract
Brown carbon (BrC), as an important light-absorbing aerosol, significantly impacts regional and global climate. Vehicle emission is a nonnegligible source of BrC, but the optical properties of BrC emitted from vehicles remain poorly understood. This study evaluates the absorption Ångström exponent (AAE) of traffic-related light-absorbing aerosols (i.e., AAETr) and the absorption emission factor (EFabs) of vehicular BrC via chassis dynamometer tests and a road tunnel measurement in Tianjin, China. AAETr are estimated as 0.98-1.33 and 1.11 ± 0.001 for tested vehicles and on-road vehicle fleet, respectively. The AAE of vehicular BrC (AAEBrC) is 3.83 ± 0.092 for on-road vehicle fleet. The vehicle technology updates effectively reduce the EFabs of vehicular BrC. Among the four tested China 5 and China 6 gasoline vehicles in the chassis dynamometer tests, BrC EFabs of China 5 gasoline direct injection vehicle is the highest, while China 6 mixing fuel injection vehicle exhibits the lowest EFabs. The BrC EFabs of on-road vehicle fleet at 370 nm wavelength are 0.081 ± 0.0058 m2 kg-1 for mixed fleet, 0.074 ± 0.018 m2 kg-1 for gasoline vehicles (GVs), and 1.66 ± 0.71 m2 kg-1 for diesel vehicles (DVs) in the tunnel measurement. EFabs of GV fleet in the road tunnel is higher than China 5 and China 6 vehicles, as China 1-4 vehicles accounted for 26.8% of the total vehicle fleet in the tunnel. EFabs of vehicular BrC are lower than those from biomass burning and coal combustion emissions. The light absorption of BrC from GVs and DVs accounts for 7.2 ± 2.1% and 1.5 ± 0.77% of total traffic-related absorption at 370 nm, respectively. Our study provides optical features of BrC from vehicle source and could contribute to estimating the impacts of vehicular aerosol emissions on global and regional climate change.
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Affiliation(s)
- Chung Song Ho
- Tianjin Key Laboratory of Urban Transport Emission Research & State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control, College of Environmental Science and Engineering, Nankai University, Tianjin, 300071, China; High-Tech Research and Development Center, Kim Il Sung University, Pyongyang, 999093, Democratic People's Republic of Korea
| | - Zongyan Lv
- Tianjin Key Laboratory of Urban Transport Emission Research & State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control, College of Environmental Science and Engineering, Nankai University, Tianjin, 300071, China
| | - Jianfei Peng
- Tianjin Key Laboratory of Urban Transport Emission Research & State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control, College of Environmental Science and Engineering, Nankai University, Tianjin, 300071, China.
| | - Jinsheng Zhang
- Tianjin Key Laboratory of Urban Transport Emission Research & State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control, College of Environmental Science and Engineering, Nankai University, Tianjin, 300071, China
| | - Tong-Hyok Choe
- Faculty of Global Environmental Science, Kim Il Sung University, Pyongyang, 999093, Democratic People's Republic of Korea
| | - Qijun Zhang
- Tianjin Key Laboratory of Urban Transport Emission Research & State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control, College of Environmental Science and Engineering, Nankai University, Tianjin, 300071, China
| | - Zhuofei Du
- Tianjin Key Laboratory of Urban Transport Emission Research & State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control, College of Environmental Science and Engineering, Nankai University, Tianjin, 300071, China
| | - Hongjun Mao
- Tianjin Key Laboratory of Urban Transport Emission Research & State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control, College of Environmental Science and Engineering, Nankai University, Tianjin, 300071, China
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31
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West CP, Morales AC, Ryan J, Misovich MV, Hettiyadura APS, Rivera-Adorno F, Tomlin JM, Darmody A, Linn BN, Lin P, Laskin A. Molecular investigation of the multi-phase photochemistry of Fe(III)-citrate in aqueous solution. ENVIRONMENTAL SCIENCE. PROCESSES & IMPACTS 2023; 25:190-213. [PMID: 35634912 DOI: 10.1039/d1em00503k] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Iron (Fe) is ubiquitous in nature and found as FeII or FeIII in minerals or as dissolved ions Fe2+ or Fe3+ in aqueous systems. The interactions of soluble Fe have important implications for fresh water and marine biogeochemical cycles, which have impacts on global terrestrial and atmospheric environments. Upon dissolution of FeIII into natural aquatic systems, organic carboxylic acids efficiently chelate FeIII to form [FeIII-carboxylate]2+ complexes that undergo a wide range of photochemistry-induced radical reactions. The chemical composition and photochemical transformations of these mixtures are largely unknown, making it challenging to estimate their environmental impact. To investigate the photochemical process of FeIII-carboxylates at the molecular level, we conduct a comprehensive experimental study employing UV-visible spectroscopy, liquid chromatography coupled to photodiode array and high-resolution mass spectrometry detection, and oil immersion flow microscopy. In this study, aqueous solutions of FeIII-citrate were photolyzed under 365 nm light in an experimental setup with an apparent quantum yield of (φ) ∼0.02, followed by chemical analyses of reacted mixtures withdrawn at increment time intervals of the experiment. The apparent photochemical reaction kinetics of Fe3+-citrates (aq) were expressed as two generalized consecutive reactions of with the experimental rate constants of j1 ∼ 0.12 min-1 and j2 ∼ 0.05 min-1, respectively. Molecular characterization results indicate that R and I consist of both water-soluble organic and Fe-organic species, while P compounds are a mixture of water-soluble and colloidal materials. The latter were identified as Fe-carbonaceous colloids formed at long photolysis times. The carbonaceous content of these colloids was identified as unsaturated organic species with low oxygen content and carbon with a reduced oxidation state, indicative of their plausible radical recombination mechanism under oxygen-deprived conditions typical for the extensively photolyzed mixtures. Based on the molecular characterization results, we discuss the comprehensive reaction mechanism of FeIII-citrate photochemistry and report on the formation of previously unexplored colloidal reaction products, which may contribute to atmospheric and terrestrial light-absorbing materials in aquatic environments.
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Affiliation(s)
- Christopher P West
- Department of Chemistry, Purdue University, West Lafayette, IN, 47906, USA.
| | - Ana C Morales
- Department of Chemistry, Purdue University, West Lafayette, IN, 47906, USA.
| | - Jackson Ryan
- Department of Chemistry, Purdue University, West Lafayette, IN, 47906, USA.
| | - Maria V Misovich
- Department of Chemistry, Purdue University, West Lafayette, IN, 47906, USA.
| | | | | | - Jay M Tomlin
- Department of Chemistry, Purdue University, West Lafayette, IN, 47906, USA.
| | - Andrew Darmody
- Department of Aeronautics and Aerospace Engineering, Purdue University, West Lafayette, IN, USA
| | - Brittany N Linn
- Department of Chemistry, Purdue University, West Lafayette, IN, 47906, USA.
| | - Peng Lin
- Department of Chemistry, Purdue University, West Lafayette, IN, 47906, USA.
| | - Alexander Laskin
- Department of Chemistry, Purdue University, West Lafayette, IN, 47906, USA.
- Department of Earth, Atmospheric & Planetary Sciences, Purdue University, West Lafayette, IN, USA
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Singh PK, Adhikary B, Chen X, Kang S, Poudel SP, Tashi T, Goswami A, Puppala SP. Variability of ambient black carbon concentration in the Central Himalaya and its assessment over the Hindu Kush Himalayan region. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 858:160137. [PMID: 36375556 DOI: 10.1016/j.scitotenv.2022.160137] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2022] [Revised: 11/07/2022] [Accepted: 11/08/2022] [Indexed: 06/16/2023]
Abstract
During 2015-2018, eight black carbon (BC) monitoring sites were established in Nepal and Bhutan to fill a significant data gap regarding BC measurement in Central Himalaya. This manuscript analyzes and presents data from these eight stations and one additional station on the Tibetan plateau (TP). Complex topography, varied emission sources, and atmospheric transport pathways significantly impacted the BC concentrations across these stations, with annual mean concentrations varying from 36 ng m-3 to 45,737 ng m-3. Higher annual mean concentrations (5609 ± 4515 ng m-3) were recorded at low-altitude sites than in other locations, with seasonal concentrations highest in the winter (7316 ± 2541 ng m-3). In contrast, the annual mean concentrations were lowest at high-altitude sites (376 ± 448 ng m-3); the BC concentrations at these sites peaked during the pre-monsoon season (930 ± 685 ng m-3). Potential source contributions to the total observed BC were analyzed using the absorption angstrom exponent (AAE). AAE analysis showed the dominance of biomass burning sources (>50 %), except in Kathmandu. By combining our data with previously published literature, we put our measurements in perspective by presenting a comprehensive assessment of BC concentrations and their variability over the Hindu Kush Himalayan (HKH) region. The BC levels in all three geographic regions, high, mid, and low altitude significantly influenced by the persistent seasonal meteorology. However, the mid-altitude stations were substantially affected by valley dynamics and urbanization. The low-altitude stations experienced high BC concentrations during the winter and post-monsoon seasons. Concentration weighted trajectory (CWT) and frequency analyses revealed the dominance of long-range transported pollution during winter over HKH, from west to east. South Asian sources remained significant during the monsoon season. During pre- and post-monsoon, the local, regional, and long-distance pollution varied depending on the location of the receptor site.
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Affiliation(s)
- Praveen Kumar Singh
- International Centre for Integrated Mountain Development (ICIMOD), G.P.O. Box 3226, Kathmandu, Nepal; Centre of Excellence in Disaster Mitigation and Management, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand 247667, India
| | - Bhupesh Adhikary
- International Centre for Integrated Mountain Development (ICIMOD), G.P.O. Box 3226, Kathmandu, Nepal
| | - Xintong Chen
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shichang Kang
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shankar Prasad Poudel
- Department of Environment, Ministry of Forests and Environment, Forest-Complex, Babarmahal, Kathmandu, Nepal
| | - Tshering Tashi
- National Environment Commission, Royal Government of Bhutan, Tashi-Chhodzong Lam, Thimphu, Bhutan
| | - Ajanta Goswami
- Centre of Excellence in Disaster Mitigation and Management, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand 247667, India; Department of Earth Sciences, Indian Institute of Technology Roorkee, Roorkee, Uttarakhand 247667, India
| | - Siva Praveen Puppala
- International Centre for Integrated Mountain Development (ICIMOD), G.P.O. Box 3226, Kathmandu, Nepal.
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Li D, Wu C, Zhang S, Lei Y, Lv S, Du W, Liu S, Zhang F, Liu X, Liu L, Meng J, Wang Y, Gao J, Wang G. Significant coal combustion contribution to water-soluble brown carbon during winter in Xingtai, China: Optical properties and sources. J Environ Sci (China) 2023; 124:892-900. [PMID: 36182192 DOI: 10.1016/j.jes.2022.02.026] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2021] [Revised: 02/13/2022] [Accepted: 02/15/2022] [Indexed: 06/16/2023]
Abstract
To understand the characteristics of atmospheric brown carbon (BrC), daily PM2.5 samples in Xingtai, a small city in North China Plain (NCP), during the four seasons of 2018-2019, were collected and analyzed for optical properties and chemical compositions. The light absorption at 365 nm (absλ=365 nm) displayed a strong seasonal variation with the highest value in winter (29.0±14.3 M/m), which was 3.2∼5.4-fold of that in other seasons. A strong correlation of absλ=365 nm with benzo(b)fluoranthene (BbF) was only observed in winter, indicating that coal combustion was the major source for BrC in the season due to the enhanced domestic heating. The mass absorbing efficiency of BrC also exhibited a similar seasonal pattern, and was found to correlate linearly with the aerosol pH, suggesting a positive effect of aerosol acidity on the optical properties and formation of BrC in the city. Positive matrix factorization (PMF) analysis further showed that on a yearly basis the major source for BrC was biomass burning, which accounted for 34% of the total BrC, followed by secondary formation (26.7%), coal combustion (21.3%) and fugitive dust (18%). However, the contribution from coal combustion was remarkably enhanced in winter, accounting for ∼40% of the total. Our work revealed that more efforts of "shifting coal to clean energy" are necessary in rural areas and small cities in NCP in order to further mitigate PM2.5 pollution in China.
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Affiliation(s)
- Dapeng Li
- Key Lab of Geographic Information Science of the Ministry of Education, School of Geographic Sciences, East China Normal University, Shanghai 200241, China
| | - Can Wu
- Key Lab of Geographic Information Science of the Ministry of Education, School of Geographic Sciences, East China Normal University, Shanghai 200241, China.
| | - Si Zhang
- Key Lab of Geographic Information Science of the Ministry of Education, School of Geographic Sciences, East China Normal University, Shanghai 200241, China
| | - Yali Lei
- Key Lab of Geographic Information Science of the Ministry of Education, School of Geographic Sciences, East China Normal University, Shanghai 200241, China
| | - Shaojun Lv
- Key Lab of Geographic Information Science of the Ministry of Education, School of Geographic Sciences, East China Normal University, Shanghai 200241, China
| | - Wei Du
- Key Lab of Geographic Information Science of the Ministry of Education, School of Geographic Sciences, East China Normal University, Shanghai 200241, China
| | - Shijie Liu
- Key Lab of Geographic Information Science of the Ministry of Education, School of Geographic Sciences, East China Normal University, Shanghai 200241, China
| | - Fan Zhang
- Key Lab of Geographic Information Science of the Ministry of Education, School of Geographic Sciences, East China Normal University, Shanghai 200241, China
| | - Xiaodi Liu
- Key Lab of Geographic Information Science of the Ministry of Education, School of Geographic Sciences, East China Normal University, Shanghai 200241, China
| | - Lang Liu
- School of Public Policy and Administration, Northwestern Polytechnical University, Xi'an 710061, China
| | - Jingjing Meng
- School of Environment and Planning, Liaocheng University, Liaocheng 252000, China
| | - Yuesi Wang
- State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100080, China
| | - Jian Gao
- Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Gehui Wang
- Key Lab of Geographic Information Science of the Ministry of Education, School of Geographic Sciences, East China Normal University, Shanghai 200241, China; Institute of Eco-Chongming, Chenjia Zhen, Chongming, Shanghai 202162, China.
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Yang X, Ji D, Li J, He J, Gong C, Xu X, Wang Z, Liu Y, Bi F, Zhang Z, Chen Y. Impacts of springtime biomass burning in Southeast Asia on atmospheric carbonaceous components over the Beibu Gulf in China: Insights from aircraft observations. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 857:159232. [PMID: 36208733 DOI: 10.1016/j.scitotenv.2022.159232] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 09/29/2022] [Accepted: 09/30/2022] [Indexed: 06/16/2023]
Abstract
Limited by the scarcity of in situ vertical observation data, the influences of biomass burning in Southeast Asia on major atmospheric carbonaceous compositions in downwind regions have not been thoroughly studied. In this study, aircraft observations were performed to obtain high time-resolved in situ vertical distributions of black carbon (BC) as well as carbon monoxide (CO) and carbon dioxide (CO2). Four types of profiles were revealed: Mode I (from 2000 to 3000 m, the BC, CO and CO2 concentrations were enhanced), Mode II (with increasing altitude, the BC, CO and CO2 concentrations almost decreased), Mode III (inhomogeneous vertical BC, CO and CO2 profiles with BC peaks were observed from 2500 to 3000 m) and Mode IV (the BC, CO and CO2 concentrations increased above 1500 m). Furthermore, simulations were conducted to calculate radiative forcing (RF) caused by BC and study the heating rate (HR) of BC in combination with the vertical BC profiles. A larger BC distribution in the atmosphere resulted in a sharp RF change from negative to positive values, imposing a nonnegligible influence on the atmospheric temperature profile, with maximum HR values ranging from 0.4 to 5.8 K/day. The values of the absorption Ångström exponent (AAE) were 1.46 ± 0.11 and 1.48 ± 0.17 at altitudes from 1000 to 2000 and 2000-3000 m, respectively. The average BC light absorption coefficient at the 370 nm wavelength (α BC (370)) accounted for 50.3 %-76.8 % of the α (370), while the brown carbon (BrC) light absorption coefficient at the 370 nm wavelength (α BrC (370)) contributed 23.2 %-49.7 % to the α (370) at altitudes of 1000-2000 m. At altitudes of 2000-3000 m, α BC (370) and α BrC (370) contributed 43.8 %-88.2 % and 11.8 %-56.2 % to the α (370), respectively. These findings show that calculations that consider the surface BC concentration but ignore the vertical BC distribution could result in massive uncertainties in estimating the RF and HR caused by BC. This study helped achieve a deeper understanding of the influences of biomass burning over the region of Southeast Asia on the profiles of atmospheric carbonaceous compositions and atmospheric BC absorption and its warming effect.
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Affiliation(s)
- Xiaoyang Yang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Dongsheng Ji
- State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100191, China.
| | - Jiawei Li
- Key Laboratory of Regional Climate-Environment for Temperate East Asia, Chinese Academy of Sciences, Beijing 10029, China
| | - Jun He
- Department of Chemical and Environmental Engineering, University of Nottingham Ningbo China, Ningbo 315100, China; Nottingham Ningbo China Beacons of Excellence Research and Innovation Institute, Ningbo 315021, China
| | - Chongshui Gong
- Institute of Arid Meteorology, China Meteorological Administration, Lanzhou 730020, China
| | - Xiaojuan Xu
- State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100191, China
| | - Zhe Wang
- State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100191, China
| | - Yu Liu
- State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry, Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100191, China
| | - Fang Bi
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Zhongzhi Zhang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Yunbo Chen
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
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35
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Li X, Guo J, Yu F, Tripathee L, Yan F, Hu Z, Gao S, He X, Li C, Kang S. Concentrations, sources, fluxes, and absorption properties of carbonaceous matter in a central Tibetan Plateau river basin. ENVIRONMENTAL RESEARCH 2023; 216:114680. [PMID: 36332672 DOI: 10.1016/j.envres.2022.114680] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2022] [Revised: 10/18/2022] [Accepted: 10/24/2022] [Indexed: 06/16/2023]
Abstract
Carbonaceous matter (CM) (such as water-insoluble organic carbon (WIOC), black carbon (BC), and water-soluble organic carbon (WSOC)) has a significant impact on the carbon cycle and radiative forcing (RF) of glacier. Precipitation samples and glacier's snow/ice samples (snowpit, surface snow, and granular ice) (Xiao dongkemadi Glacier) were collected at the Dongkemadi River Basin (DRB) in the central Tibetan Plateau (TP) between May and October 2016 to investigate the characteristics and roles of CM in the TP River Basin. WIOC, BC, and WSOC concentrations in precipitation were relatively higher than that in snowpit, but lower than that in surface snow/ice, with the wet deposition fluxes of 0.10 ± 0.002, 0.04 ± 0.001, and 0.12 ± 0.002 g C m-2 yr-1 at DRB, respectively. The positive matrix factorization model identified four major sources (biomass burning source, secondary precursors, secondary aerosol, and dust source) of CM in precipitation at DRB. Two source areas (South Asia and the interior of TP) contributing to the pollution at DRB were identified using a potential source contribution function model, a concentration-weighted trajectory method, and the back-trajectory model. Moreover, the light-absorption by WSOC in the ultraviolet region was 23.0%, 12.1%, and 3.4% relative to the estimated total light-absorption in precipitation, snowpit, and surface snow/ice, respectively. Optical indices analysis revealed that WSOC in snowpit samples presented higher molecular weight, while presented higher aromatic and higher molecule sizes in surface snow/ice and precipitation samples, respectively. RF by WSOC relative to that of BC was estimated to be 17.6 ± 17.6% for precipitation, 10.9 ± 5.8% for snowpit, and 10.7 ± 11.6% for surface snow/ice, respectively, during the melt season in the central TP River Basin. These results help us understand how CM affects glaciers, and they can be utilized to create policies and recommendations that efficiently reduce emissions.
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Affiliation(s)
- Xiaofei Li
- School of Environmental Science and Engineering, Shaanxi University of Science and Technology, Xi'an, 710021, China; State Key Laboratory of Loess and Quaternary Geology, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an, 710061, China; Tanggula Cryosphere and Environment Observation Station, Lanzhou, 730000, China; State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China.
| | - Jingning Guo
- School of Environmental Science and Engineering, Shaanxi University of Science and Technology, Xi'an, 710021, China
| | - Feng Yu
- School of Environmental Science and Engineering, Shaanxi University of Science and Technology, Xi'an, 710021, China
| | - Lekhendra Tripathee
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China
| | - Fangping Yan
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China
| | - Zhaofu Hu
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China
| | - Shaopeng Gao
- State Key Laboratory of Tibetan Plateau Earth System, Resources and Environment (TPESRE), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China
| | - Xiaobo He
- Tanggula Cryosphere and Environment Observation Station, Lanzhou, 730000, China; State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China
| | - Chaoliu Li
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China
| | - Shichang Kang
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China; University of Chinese Academy of Sciences, Beijing, 100049, China.
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Font A, Ciupek K, Butterfield D, Fuller GW. Long-term trends in particulate matter from wood burning in the United Kingdom: Dependence on weather and social factors. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2022; 314:120105. [PMID: 36089148 DOI: 10.1016/j.envpol.2022.120105] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2022] [Revised: 08/07/2022] [Accepted: 09/01/2022] [Indexed: 06/15/2023]
Abstract
Particulate matter from wood burning emissions (Cwood) was quantified at five locations in the United Kingdom (UK), comprising three rural and two urban sites between 2009 and 2021. The aethalometer method was used. Mean winter Cwood concentrations ranged from 0.26 μg m-3 (in rural Scotland) to 1.30 μg m-3 (London), which represented on average 4% (in rural environments) and 5% (urban) of PM10 concentrations; and 8% of PM2.5. Concentrations were greatest in the evenings in winter months, with larger evening concentrations in the weekends at the urban sites. Random-forest (RF) machine learning regression models were used to reconstruct Cwood concentrations using both meteorological and temporal explanatory variables at each site. The partial dependency plots indicated that temperature and wind speed were the meteorological variables explaining the greatest variability in Cwood, with larger concentrations during cold and calm conditions. Peaks of Cwood concentrations took place during and after events that are celebrated with bonfires. These were Guy Fawkes events in the urban areas and on New Year's Day at the rural sites; the later probably related to long-range transport. Time series were built using the RF. Having removed weather influences, long-term trends of Cwood were estimated using the Theil Sen method. Trends for 2015-2021 were downward at three of the locations (London, Glasgow and rural Scotland), with rates ranging from -5.5% year-1 to -2.5% year-1. The replacement of old fireplaces with lower emission wood stoves might explain the decrease in Cwood especially at the urban sites The two rural sites in England observed positive trends for the same period but this was not statistically significant.
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Affiliation(s)
- A Font
- MRC Centre for Environment and Health, Environmental Research Group, Imperial College, London, UK.
| | - K Ciupek
- MRC Centre for Environment and Health, Environmental Research Group, Imperial College, London, UK; Air Quality and Aerosol Metrology Group, National Physical Laboratory, Teddington, UK
| | - D Butterfield
- Air Quality and Aerosol Metrology Group, National Physical Laboratory, Teddington, UK
| | - G W Fuller
- MRC Centre for Environment and Health, Environmental Research Group, Imperial College, London, UK
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Zhu CS, Qu Y, Dai WT, Su XL, Zhou JM, Wang N, Qu J, Cao JJ. Comparison of black carbon, primary and secondary brown carbon light absorption and direct solar absorption at the foothill and summit of Mt. Hua, China. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 848:157814. [PMID: 35931170 DOI: 10.1016/j.scitotenv.2022.157814] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/25/2022] [Revised: 07/25/2022] [Accepted: 07/31/2022] [Indexed: 06/15/2023]
Abstract
Atmospheric black carbon (BC), primary and secondary brown carbon (BrCpri and BrCsec) are the light-absorbing carbonaceous aerosol components. The vertical changes in the BC and BrC distributions are not generally known. Here, we presented a study of the spectral light absorption properties, direct solar absorption, and potential source areas of BC and BrC at the foothill (375 m a.s.l.) and summit (2060 m a.s.l.) of Mt. Hua, China. More than tripled BC and BrC light absorption coefficient were observed at the foothill compared to the summit. The dominant carbonaceous light-absorbing was attributed to BC with the percentages of 77 % (foothill) and 79 % (summit), respectively. The light absorption coefficient and direct solar absorption of BrCpri were much higher than those of BrCsec at foothill, especially in winter. The enhancing contributions of BrCsec light absorption coefficient and direct solar absorption were observed with high RH and visibility at the summit. The light absorption properties of BC, BrCpri, and BrCsec may be attributed to the emissions, meteorological conditions, and photochemical oxidation. The inferred potential source spatial distributions of BC and BrCpri showed different patterns at the foothill and summit. The results underlined the primary emission effects (including BC and BrCpri) at the foothill and the importance of BrCsec at the summit, respectively.
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Affiliation(s)
- Chong-Shu Zhu
- CAS Center for Excellence in Quaternary Science and Global Change, SKLLQG, and KLACP, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China; National Observation and Research Station of Regional Ecological Environment Change and Comprehensive Management in the Guanzhong Plain, Xi'an 710061, China.
| | - Yao Qu
- CAS Center for Excellence in Quaternary Science and Global Change, SKLLQG, and KLACP, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China; National Observation and Research Station of Regional Ecological Environment Change and Comprehensive Management in the Guanzhong Plain, Xi'an 710061, China
| | - Wen-Ting Dai
- CAS Center for Excellence in Quaternary Science and Global Change, SKLLQG, and KLACP, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China; National Observation and Research Station of Regional Ecological Environment Change and Comprehensive Management in the Guanzhong Plain, Xi'an 710061, China
| | - Xiao-Li Su
- CAS Center for Excellence in Quaternary Science and Global Change, SKLLQG, and KLACP, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China; National Observation and Research Station of Regional Ecological Environment Change and Comprehensive Management in the Guanzhong Plain, Xi'an 710061, China
| | - Jia-Mao Zhou
- CAS Center for Excellence in Quaternary Science and Global Change, SKLLQG, and KLACP, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China; National Observation and Research Station of Regional Ecological Environment Change and Comprehensive Management in the Guanzhong Plain, Xi'an 710061, China
| | - Nan Wang
- Xi'an Institute for Innovative Earth Environment Research, Xi'an 710061, China; National Observation and Research Station of Regional Ecological Environment Change and Comprehensive Management in the Guanzhong Plain, Xi'an 710061, China
| | - Jing Qu
- Xi'an Meteorological Administration, Xi'an 710016, China
| | - Jun-Ji Cao
- CAS Center for Excellence in Quaternary Science and Global Change, SKLLQG, and KLACP, Institute of Earth Environment, Chinese Academy of Sciences, Xi'an 710061, China; Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China; National Observation and Research Station of Regional Ecological Environment Change and Comprehensive Management in the Guanzhong Plain, Xi'an 710061, China
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Zhai L, An Y, Feng L, Qin X, Xu J. Contrasting the physical and chemical characteristics of dissolved organic matter between glacier and glacial runoff from a mountain glacier on the Tibetan Plateau. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 848:157784. [PMID: 35926601 DOI: 10.1016/j.scitotenv.2022.157784] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2022] [Revised: 07/28/2022] [Accepted: 07/29/2022] [Indexed: 06/15/2023]
Abstract
Accelerated melting of mountain glaciers due to global warming has a significant impact on downstream biogeochemical evolution because a large amount of labile dissolved organic matter (DOM) is released. However, the DOM evolution processes from glacier to downstream are not well understood. To investigate these processes, samples from the glacial surface and terminating runoff of a mountain glacier on the Tibetan Plateau were collected simultaneously throughout the melting season. The samples were analyzed to determine the dissolved organic carbon (DOC) contents and chemical compositions by means of a combination of fluorescence excitation-emission matrix coupled with parallel factor analysis (EEM-PARAFAC) and Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS). The results indicate that the DOC concentrations were higher in the snow samples than in the glacial runoff samples, although a significantly higher concentration of inorganic ions was found in the glacial runoff samples, suggesting the dominant source of DOM in the glacial runoff was the glacier. The EEM-PARAFAC revealed four fluorescent components in both the snow and glacial runoff samples. However, significantly different ratios between the four components of these two categories of samples suggested chemical, physical and/or biological evolution of DOM during transport. Molecular chemical composition analyses by FT-ICR MS revealed that the DOM composition varied dramatically between the glacier and the glacial runoff. More than 50 % of the molecules were transformed from aliphatic and peptide-like compounds in the snow samples into highly unsaturated and phenolic-like compounds in the glacial runoff samples. The potential chemical transformation of DOM was likely related to biological and/or photolytic evolution during transport. Our results suggest that chemical evolution of glacial DOM could occur during the downstream transport, which is expected to be useful for further research exploring the fate of DOM and carbon cycling from the cryospheric environment and evaluating the biogeochemical effects.
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Affiliation(s)
- Lixiang Zhai
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yanqing An
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China
| | - Lin Feng
- Aba Teachers University, Wenchuan 623002, China
| | - Xiang Qin
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China
| | - Jianzhong Xu
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China.
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Aslam I, Roeffaers MBJ. Carbonaceous Nanoparticle Air Pollution: Toxicity and Detection in Biological Samples. NANOMATERIALS (BASEL, SWITZERLAND) 2022; 12:nano12223948. [PMID: 36432235 PMCID: PMC9698098 DOI: 10.3390/nano12223948] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Revised: 11/04/2022] [Accepted: 11/05/2022] [Indexed: 05/27/2023]
Abstract
Among the different air pollutants, particulate matter (PM) is of great concern due to its abundant presence in the atmosphere, which results in adverse effects on the environment and human health. The different components of PM can be classified based on their physicochemical properties. Carbonaceous particles (CPs) constitute a major fraction of ultrafine PM and have the most harmful effects. Herein, we present a detailed overview of the main components of CPs, e.g., carbon black (CB), black carbon (BC), and brown carbon (BrC), from natural and anthropogenic sources. The emission sources and the adverse effects of CPs on the environment and human health are discussed. Particularly, we provide a detailed overview of the reported toxic effects of CPs in the human body, such as respiratory effects, cardiovascular effects, neurodegenerative effects, carcinogenic effects, etc. In addition, we also discuss the challenges faced by and limitations of the available analytical techniques for the qualitative and quantitative detection of CPs in atmospheric and biological samples. Considering the heterogeneous nature of CPs and biological samples, a detailed overview of different analytical techniques for the detection of CPs in (real-exposure) biological samples is also provided. This review provides useful insights into the classification, toxicity, and detection of CPs in biological samples.
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Boreddy SKR, Hegde P, Arun BS, Aswini AR, Babu SS. Molecular composition and light-absorbing properties of organic aerosols from west-coast of tropical India. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 845:157163. [PMID: 35798104 DOI: 10.1016/j.scitotenv.2022.157163] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 06/20/2022] [Accepted: 06/30/2022] [Indexed: 06/15/2023]
Abstract
Tropical coastal regions may provide a unique feature to study the photooxidation of various organic aerosols and their climatic effects because of high humid atmosphere and intense solar radiation. However, knowledge about organic molecular composition and its light absorption properties remains concealed, particularly over tropical Indian regions. The present study is an investigation on water-soluble dicarboxylic acids, ω-oxoacids, pyruvic acid, α-dicarbonyls, brown carbon (BrC), and other chemical species in PM1.1 collected at a coastal urban location (Kochi) on the west coast of tropical India under distinct air masses. Molecular distribution of dicarboxylic acids was characterized by the predominance of oxalic acid (C2) in all the air masses followed by adipic (C6) or terephthalic (tPh) and phthalic (Ph) acids. On average, total diacids-C accounted for 5.03 ± 1.01 % of TC. Total diacid concentration showed strong linear relationships with organic (OC), elemental carbon (EC), and non-sea-salt potassium (nss-K+). Except for the northwest (NW) air mass period, the concentration of C2 diacid and its ratios (C2/total diacids, C2/ωC2, C2/Gly) showed a strong linear relationship with nss-SO42-. By combining all these results together with Pearson correlation analysis, the present study demonstrates that organic aerosols over the study region were predominantly produced by aqueous-phase oxidation of precursor compounds derived from biomass burning and combustion-related emissions. The mass absorption coefficient of BrC (babs-BrC-365nm) was strongly correlated with nss-K+, implying that biomass burning emissions are major sources of BrC. The absorption angstrom exponent (AÅE) values of water (methanol) extracts ranged from 3.20 to 3.83 (3.05-4.55) during the entire sampling period, indicating the substantial contribution of BrC chromophores to light absorption over the region. On average, BrC absorbs 10.6 ± 6.4 % and 22.4 ± 5.75 % of solar radiation compared to BC in water and methanol extracts, respectively, suggesting that BrC is a significant aerosol climate forcing agent over the west coast of tropical India.
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Affiliation(s)
- Suresh K R Boreddy
- Space Physics Laboratory, Vikram Sarabhai Space Centre, Thiruvananthapuram 695022, India; Department of Physics and Nanotechnology, SRM Institute of Science and Technology, Kattankulathur 603203, India
| | - Prashant Hegde
- Space Physics Laboratory, Vikram Sarabhai Space Centre, Thiruvananthapuram 695022, India.
| | - B S Arun
- Space Physics Laboratory, Vikram Sarabhai Space Centre, Thiruvananthapuram 695022, India
| | - A R Aswini
- Space Physics Laboratory, Vikram Sarabhai Space Centre, Thiruvananthapuram 695022, India
| | - S Suresh Babu
- Space Physics Laboratory, Vikram Sarabhai Space Centre, Thiruvananthapuram 695022, India
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Xiong R, Li J, Zhang Y, Zhang L, Jiang K, Zheng H, Kong S, Shen H, Cheng H, Shen G, Tao S. Global brown carbon emissions from combustion sources. ENVIRONMENTAL SCIENCE AND ECOTECHNOLOGY 2022; 12:100201. [PMID: 36157345 PMCID: PMC9500369 DOI: 10.1016/j.ese.2022.100201] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 07/10/2022] [Accepted: 07/11/2022] [Indexed: 05/06/2023]
Abstract
Light-absorbing organic carbon (OC), sometimes known as Brown Carbon (BrC), has been recognized as an important fraction of carbonaceous aerosols substantially affecting radiative forcing. This study firstly developed a bottom-up estimate of global primary BrC, and discussed its spatiotemporal distribution and source contributions from 1960 to 2010. The global total primary BrC emission from both natural and anthropogenic sources in 2010 was 7.26 (5.98-8.93 as an interquartile range) Tg, with 43.5% from anthropogenic sources. High primary BrC emissions were in regions such as Africa, South America, South and East Asia with natural sources (wild fires and deforestation) contributing over 70% in the former two regions, while in East Asia, anthropogenic sources, especially residential solid fuel combustion, accounted for over 80% of the regional total BrC emissions. Globally, the historical trend was mainly driven by anthropogenic sources, which increased from 1960 to 1990 and then started to decline. Residential emissions significantly impacted on emissions and temporal trends that varied by region. In South and Southeast Asia, the emissions increased obviously due to population growth and a slow transition from solid fuels to clean modern energies in the residential sector. It is estimated that in primary OC, the global average was about 20% BrC, but this ratio varied from 13% to 47%, depending on sector and region. In areas with high residential solid fuel combustion emissions, the ratio was generally twice the value in other areas. Uncertainties in the work are associated with the concept of BrC and measurement technologies, pointing to the need for more studies on BrC analysis and quantification in both emissions and the air.
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Affiliation(s)
- Rui Xiong
- Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
| | - Jin Li
- Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
| | - Yuanzheng Zhang
- Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
| | - Lu Zhang
- Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
| | - Ke Jiang
- Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
| | - Huang Zheng
- Department of Environmental Science and Technology, School of Environmental Studies, China University of Geosciences, Wuhan, 430074, China
| | - Shaofei Kong
- Department of Environmental Science and Technology, School of Environmental Studies, China University of Geosciences, Wuhan, 430074, China
| | - Huizhong Shen
- School of Environmental Sciences and Engineering, Southern University of Science and Technology, Shenzhen, 518055, China
| | - Hefa Cheng
- Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
| | - Guofeng Shen
- Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
| | - Shu Tao
- Laboratory for Earth Surface Processes, College of Urban and Environmental Sciences, Peking University, Beijing, 100871, China
- School of Environmental Sciences and Engineering, Southern University of Science and Technology, Shenzhen, 518055, China
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Mukherjee S, Verma A, Meena GS, Kodoli S, Buchunde P, Aslam MY, Patil RD, Panicker A, Safai PD, Pandithurai G. Compensatory effect of biomass burning on black carbon concentrations during COVID-19 lockdown at a high-altitude station in SW India. ATMOSPHERIC POLLUTION RESEARCH 2022; 13:101566. [PMID: 36187213 PMCID: PMC9514839 DOI: 10.1016/j.apr.2022.101566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/28/2021] [Revised: 09/23/2022] [Accepted: 09/24/2022] [Indexed: 06/16/2023]
Abstract
The characteristics of black carbon (BC) aerosols, their sources, and their impact on atmospheric radiative forcing were extensively studied during the COVID-19 lockdown (28th March-31st May 2020) at a high-altitude rural site over the Western Ghats in southwest India. BC concentration and the contribution of BC originating from biomass burning (BCbb) estimated from the aethalometer model during the lockdown period were compared with the same periods in 2017 and 2018 and with the pre-lockdown period (1st February to March 20, 2020). BC concentrations were 44, 19, and 17% lower during the lockdown period compared with the pre-lockdown periods of 2020 and similar periods (28th March to 31st May) of 2017 and 2018, respectively. BCbb contributed ∼50% to total BC during the lockdown period of 2020 and compensated for the decrease in BC concentration due to lower traffic emissions. The characteristics of light-absorbing organic carbon (brown carbon; BrC) absorption at 370 nm were evaluated during the lockdown and the pre-lockdown periods of 2020, 2017, and 2018. The BrC was estimated to be the highest during the lockdown period of 2020. Finally, atmospheric radiative forcing was calculated using the mean BC concentration during the pre-lockdown, lockdown, and similar periods (28th March to 31st May) of 2017 and 2018.
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Affiliation(s)
- Subrata Mukherjee
- Indian Institute of Tropical Meteorology, Ministry of Earth Sciences, Pune, India
- Savitribai Phule Pune University, India
| | | | - Guman Singh Meena
- Indian Institute of Tropical Meteorology, Ministry of Earth Sciences, Pune, India
| | - Sandeep Kodoli
- Indian Institute of Tropical Meteorology, Ministry of Earth Sciences, Pune, India
| | - Pallavi Buchunde
- Indian Institute of Tropical Meteorology, Ministry of Earth Sciences, Pune, India
- Savitribai Phule Pune University, India
| | | | - Rohit Dilip Patil
- Indian Institute of Tropical Meteorology, Ministry of Earth Sciences, Pune, India
| | - Abhilash Panicker
- Indian Institute of Tropical Meteorology, Ministry of Earth Sciences, Pune, India
| | | | - Govindan Pandithurai
- Indian Institute of Tropical Meteorology, Ministry of Earth Sciences, Pune, India
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A New Photoacoustic Soot Spectrophone for Filter-Free Measurements of Black Carbon at 880 nm. MOLECULES (BASEL, SWITZERLAND) 2022; 27:molecules27186065. [PMID: 36144798 PMCID: PMC9506448 DOI: 10.3390/molecules27186065] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/30/2022] [Revised: 09/01/2022] [Accepted: 09/14/2022] [Indexed: 11/18/2022]
Abstract
A new photoacoustic soot spectrometer (PASS) operating at 880 nm was developed, for the first time, for filter-free measurements of black carbon (BC). The performance of the developed PASS was characterized and evaluated using a reference aethalometer AE51 on incense smoke in the air. An excellent correlation on the measurement of incense smoke was found between the two instruments in comparison with a regression coefficient of 0.99. A 1 σ detection limit of 0.8 µg m−3 was achieved for BC measurement at a time resolution of 1 s. It can be further reduced to 0.1 µg m−3, using a longer integration time of 1 min.
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Santiago-De La Rosa N, Mugica-Álvarez V, González-Cardoso G, De Vizcaya-Ruiz A, Uribe-Ramírez M, Valle-Hernández BL. Emission Factors of Polycyclic Aromatic Hydrocarbons and Oxidative Potential of Fine Particles Emitted from Crop Residues Burning. Polycycl Aromat Compd 2022. [DOI: 10.1080/10406638.2021.1924801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Affiliation(s)
- Naxieli Santiago-De La Rosa
- Universidad Autónoma Metropolitana, Ciudad de México, Mexico
- Centro de Ciencias de la Atmósfera, Universidad Nacional Autónoma de México, Ciudad de México, Mexico
| | | | | | - Andrea De Vizcaya-Ruiz
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional. Av. Instituto Politécnico Nacional, CDMX, Mexico
| | - Marisela Uribe-Ramírez
- Departamento de Toxicología, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional. Av. Instituto Politécnico Nacional, CDMX, Mexico
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Zhu S, Zhang H, Zhou C, Wei X, Liu Y. Optical properties of mixed black and brown carbon aerosols. OPTICS EXPRESS 2022; 30:33588-33602. [PMID: 36242390 DOI: 10.1364/oe.470171] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/12/2022] [Accepted: 08/18/2022] [Indexed: 06/16/2023]
Abstract
Based on actual atmospheric observations of internal mixing of light-absorbing brown carbon (BrC)-coated black carbon (BC), the optical properties of mixed black and brown carbon aerosols (BBC) were calculated using four mixing models (external mixing, core-shell, Bruggeman, and Maxwell-Garnett models), and changes in their optical properties with wavelength were compared and analyzed. Under the assumption of different volumetric mixing ratios (VR=VBC/VBBC), there is little difference in volumetric absorptive coefficient (Kab) of BBC in these models in the ultraviolet band where both BC and BrC have strong absorption, particularly in the ultraviolet A band. In visible and near-infrared bands, the three internal mixing models significantly reduce the single scattering albedo compared to the external mixing scenario. In addition, the widely used core-shell model was used to evaluate the effects of BrC shell thickness and environmental relative humidity (RH) on the optical properties of BBC. The impacts of these factors are mainly seen in ultraviolet and visible bands. The volumetric extinction coefficient (Kex) decreases with BrC shell thickness under a fixed BC core radius (0.12 µm) in these bands. This is because the radiation reaching the surface of BC particles is reduced under the absorption of less efficient BrC shells (known as the blocking effect), which is different from the BC and light-scattering aerosols internal mixing scenario. Moreover, the Kex and Kab of BBC decrease with RH, which is mainly due to both the increasing thickness of the BrC shell and the change in the complex refractive index of the BrC shell. Based on the assumptions of unchanged BC core parameters and actual observations, the extinction ability increases when BrC particles are more light-scattering in the ultraviolet and visible bands. The increase in extinction is mainly from scattering, rather than absorption. However, the situation is the opposite in the near-infrared band.
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Tohidi R, Farahani VJ, Sioutas C. Real-time measurements of mineral dust concentration in coarse particulate matter (PM 10-2.5) by employing a novel optical-based technique in Los Angeles. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 838:156215. [PMID: 35623535 DOI: 10.1016/j.scitotenv.2022.156215] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 05/01/2022] [Accepted: 05/21/2022] [Indexed: 06/15/2023]
Abstract
As a primary component of coarse particulate matter (PM), ambient mineral dust has been linked to adverse health effects. Los Angeles, the largest metropolitan urban area of the United States, is impacted by both windblown and localized sources of mineral dust, often internally mixed with black carbon. The estimation of mineral dust concentrations with a high time resolution becomes critical in improving our understanding of its sources and temporal trends. Using Aethalometers combined with a high-volume virtual impactor (VI) to enrich coarse (2.5 <dp < 10 μm) particles, the light absorption and mass concentration of mineral dust were estimated in real-time during summer, fall, and winter over 2020-2021. The concentration-enriched coarse PM was collected on Teflon filters, and its chemical composition in terms of trace elements and metals was chemically quantified. The high time-resolution measurements enabled us to calculate the absorption coefficient of enriched dust particles by subtracting the light absorption of the post-VI coarse PM from that of the PM2.5 aerosol fraction to reduce the impact of stronger light absorbers in ambient PM. Mineral dust was more prevalent during the fall and winter campaigns (i.e., 19.3 and 11.4 μg/m3, respectively), lower concentrations were observed during the summer campaign (i.e., 8.50 μg/m3). The calculated absorption Ångström exponent (AAE) was 2.18, highlighting the presence of dust particles during the sampling period. The dust mass absorption coefficient was estimated to be 2.7 ± 1.6 Mm-1 at 370 nm and 0.41 ± 0.16 Mm-1 at 880 nm wavelengths, respectively. The validation of the proposed approach was investigated by comparing the evaluated mineral dust mass concentrations in this study with the reported coarse PM concentrations by the California Air Resources Board (CARB). The results reported by the optical-based approach with high temporal resolution can provide crucial information on identifying sources of mineral dust in urban areas.
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Affiliation(s)
- Ramin Tohidi
- University of Southern California, Department of Civil and Environmental Engineering, Los Angeles, CA, USA
| | - Vahid Jalali Farahani
- University of Southern California, Department of Civil and Environmental Engineering, Los Angeles, CA, USA
| | - Constantinos Sioutas
- University of Southern California, Department of Civil and Environmental Engineering, Los Angeles, CA, USA.
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Zhan Y, Li J, Tsona NT, Chen B, Yan C, George C, Du L. Seasonal variation of water-soluble brown carbon in Qingdao, China: Impacts from marine and terrestrial emissions. ENVIRONMENTAL RESEARCH 2022; 212:113144. [PMID: 35341756 DOI: 10.1016/j.envres.2022.113144] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 03/10/2022] [Accepted: 03/17/2022] [Indexed: 06/14/2023]
Abstract
Brown carbon (BrC) has been attracting more and more attention owing to its significant effects on climate. However, the limited knowledge on its chemical composition and sources limits the precision of aerosol radiative forcing estimated by climate models. In this study, the chemical components of PM2.5 and optical properties of water-soluble BrC (WS-BrC) were investigated from atmospheric particles collected in summer and winter in Qingdao, China. On the whole, though there were slight diurnal variations, seasonal differences were more obvious. Due to the influence of emission sources and meteorological conditions, the heavier pollution of carbonaceous aerosols occurred in winter. By comparison, the absorption Ångström exponent (AAE) and mass absorption efficiency of WS-BrC at 365 nm (MAE365) showed that WS-BrC in winter had stronger wavelength dependence and light absorption capacity, which might be associated with biomass burning source contributions. This was further confirmed by a strong correlation between the light absorption coefficient at 365 nm (Abs365) and non-sea salt K+, an indicator for biomass burning emissions. Four fluorescent components (C1∼C4) with high unsaturation in water-soluble organic carbon (WSOC) were identified by excitation-emission matrix fluorescence spectroscopy combined with parallel factor analysis method, which showed that WSOC in Qingdao was mainly related to humic-like chromophores. It is worth noting that C1 was similar to the water-soluble chromophore of simulated marine aerosols, which proved that marine emissions do have a certain impact on atmospheric particulate matter in coastal areas. In addition, the results of source analysis showed that WS-BrC originated from different terrestrial sources in different seasons. The current results may help to improve the knowledge of optical properties of WS-BrC in coastal cities, optimize the global climate model and formulate air management policies.
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Affiliation(s)
- Yanan Zhan
- Environment Research Institute, Shandong University, Binhai Road 72, Qingdao, 266237, China
| | - Jianlong Li
- Environment Research Institute, Shandong University, Binhai Road 72, Qingdao, 266237, China
| | - Narcisse T Tsona
- Environment Research Institute, Shandong University, Binhai Road 72, Qingdao, 266237, China
| | - Bing Chen
- Environment Research Institute, Shandong University, Binhai Road 72, Qingdao, 266237, China
| | - Caiqing Yan
- Environment Research Institute, Shandong University, Binhai Road 72, Qingdao, 266237, China
| | - Christian George
- Université Lyon, Université Claude Bernard Lyon 1, CNRS, IRCELYON, F-69626, Villeurbanne, France
| | - Lin Du
- Environment Research Institute, Shandong University, Binhai Road 72, Qingdao, 266237, China.
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Pani SK, Lin NH, Lee CT, Griffith SM, Chang JHW, Hsu BJ. Insights into aerosol chemical composition and optical properties at Lulin Atmospheric Background Station (2862 m asl) during two contrasting seasons. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 834:155291. [PMID: 35439502 DOI: 10.1016/j.scitotenv.2022.155291] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2022] [Revised: 04/06/2022] [Accepted: 04/11/2022] [Indexed: 06/14/2023]
Abstract
Continental outflows from peninsular Southeast Asia and East Asia dominate the widespread dispersal of air pollutants over subtropical western North Pacific during spring and autumn, respectively. This study analyses the chemical composition and optical properties of PM10 aerosols during autumn and spring at a representative high-altitude site, viz., Lulin Atmospheric Background Station (23.47°N, 120.87°E; 2862 m a.s.l.), Taiwan. PM10 mass was reconstructed and the contributions of major chemical components were also delineated. Aerosol scattering (σsp) and absorption (σap) coefficients were regressed on mass densities of major chemical components by assuming external mixing between them, and the site-specific mass scattering efficiency (MSE) and mass absorption efficiency (MAE) of individual components for dry conditions were determined. NH4NO3 exhibited the highest MSE among all components during both seasons (8.40 and 12.58 m2 g-1 at 550 nm in autumn and spring, respectively). (NH4)2SO4 and organic matter (OM) accounted for the highest σsp during autumn (51%) and spring (50%), respectively. Mean MAE (mean contribution to σap) of elemental carbon (EC) at 550 nm was 2.51 m2 g-1 (36%) and 7.30 m2 g-1 (61%) in autumn and spring, respectively. Likewise, the mean MAE (mean contribution to σap) of organic carbon (OC) at 550 nm was 0.84 m2 g-1 (64%) and 0.83 m2 g-1 (39%) in autumn and spring, respectively. However, a classification matrix, based on scattering Ångström exponent, absorption Ångström exponent, and single scattering albedo (ω), demonstrated that the composite absorbing aerosols were EC-dominated (with weak absorption; ω = 0.91-0.95) in autumn and a combination of EC-dominated and EC/OC mixture (with moderate absorption; ω = 0.85-0.92) in spring. This study demonstrates a strong link between chemical composition and optical properties of aerosol and provides essential information for model simulations to assess the imbalance in regional radiation budget with better accuracy over the western North Pacific.
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Affiliation(s)
- Shantanu Kumar Pani
- Department of Atmospheric Sciences, National Central University, Taoyuan 32001, Taiwan.
| | - Neng-Huei Lin
- Department of Atmospheric Sciences, National Central University, Taoyuan 32001, Taiwan; Center for Environmental Monitoring and Technology, National Central University, Taoyuan 32001, Taiwan
| | - Chung-Te Lee
- Graduate Institute of Environmental Engineering, National Central University, Taoyuan 32001, Taiwan.
| | - Stephen M Griffith
- Department of Atmospheric Sciences, National Central University, Taoyuan 32001, Taiwan
| | - Jackson Hian-Wui Chang
- Department of Atmospheric Sciences, National Central University, Taoyuan 32001, Taiwan; Preparatory Center for Science and Technology, University Malaysia Sabah, Kota Kinabalu 88400, Malaysia
| | - Bo-Jun Hsu
- Graduate Institute of Environmental Engineering, National Central University, Taoyuan 32001, Taiwan
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Zhang C, Gao S, Yan F, Kang S, He C, Li C. An overestimation of light absorption of brown carbon in ambient particles caused by using filters with large pore size. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 833:155286. [PMID: 35429555 DOI: 10.1016/j.scitotenv.2022.155286] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2022] [Revised: 03/30/2022] [Accepted: 04/11/2022] [Indexed: 06/14/2023]
Abstract
As an important component of carbonaceous particles, organic carbon (OC) plays a significant role in radiative forcing in the atmosphere. Recently, the warming effect of light-absorbing OC has been emphasized. Water-soluble organic carbon (WSOC) is commonly used as a surrogate to investigate the light absorption of OC. Thus far, filters with 0.45 μm (PS1) and 0.20 μm pore sizes (PS2) are both used to investigate the light absorption of WSOC, which may cause large divergent results. In this study, we found that the light absorption ability of WSOC treated with PS1 was higher than that of PS2 due to the extinction of suspended particles (e.g., black carbon) with particle size between 0.20 μm and 0.45 μm, although the concentrations of WSOC treated with PS1 and PS2 were very close. This phenomenon was more remarkable at visible wavelengths, resulting in an overestimation of the warming effect of WSOC by 9%-22% for aerosol samples treated by PS1, with the highest values occurring in samples heavily influenced by fossil fuel burning emissions. An overestimation of WSOC light absorption treated by PS1 occurred in the investigated ambient aerosol samples from three sites, so it may be a general phenomenon that also exists in other regions of the world. Therefore, to achieve the actual solar radiative forcing of OC in the atmosphere, it is recommended to use PS2 in the future, and reported data of WSOC treated by PS1 should be re-evaluated.
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Affiliation(s)
- Chao Zhang
- State Key Laboratory of Tibetan Plateau Earth System, Resources and Environment (TPESRE), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shaopeng Gao
- State Key Laboratory of Tibetan Plateau Earth System, Resources and Environment (TPESRE), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China
| | - Fangping Yan
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China
| | - Shichang Kang
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Cenlin He
- Research Applications Laboratory, National Center for Atmospheric Research, Boulder, CO 80301, USA
| | - Chaoliu Li
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou 730000, China; University of Chinese Academy of Sciences, Beijing 100049, China.
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Gren L, Krais AM, Assarsson E, Broberg K, Engfeldt M, Lindh C, Strandberg B, Pagels J, Hedmer M. Underground emissions and miners' personal exposure to diesel and renewable diesel exhaust in a Swedish iron ore mine. Int Arch Occup Environ Health 2022; 95:1369-1388. [PMID: 35294627 PMCID: PMC9273542 DOI: 10.1007/s00420-022-01843-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Accepted: 02/09/2022] [Indexed: 11/10/2022]
Abstract
PURPOSE Underground diesel exhaust exposure is an occupational health risk. It is not known how recent intensified emission legislation and use of renewable fuels have reduced or altered occupational exposures. We characterized these effects on multipollutant personal exposure to diesel exhaust and underground ambient air concentrations in an underground iron ore mine. METHODS Full-shift personal sampling (12 workers) of elemental carbon (EC), nitrogen dioxide (NO2), polycyclic aromatic hydrocarbons (PAHs), and equivalent black carbon (eBC) was performed. The study used and validated eBC as an online proxy for occupational exposure to EC. Ambient air sampling of these pollutants and particle number size distribution and concentration were performed in the vicinity of the workers. Urine samples (27 workers) were collected after 8 h exposure and analyzed for PAH metabolites and effect biomarkers (8-oxodG for DNA oxidative damage, 4-HNE-MA for lipid peroxidation, 3-HPMA for acrolein). RESULTS The personal exposures (geometric mean; GM) of the participating miners were 7 µg EC m-3 and 153 µg NO2 m-3, which are below the EU occupational exposure limits. However, exposures up to 94 µg EC m-3 and 1200 µg NO2 m-3 were observed. There was a tendency that the operators of vehicles complying with sharpened emission legislation had lower exposure of EC. eBC and NO2 correlated with EC, R = 0.94 and R = 0.66, respectively. No correlation was found between EC and the sum of 16 priority PAHs (GM 1790 ng m-3). Ratios between personal exposures and ambient concentrations were similar and close to 1 for EC and NO2, but significantly higher for PAHs. Semi-volatile PAHs may not be effectively reduced by the aftertreatment systems, and ambient area sampling did not predict the personal airborne PAHs exposure well, neither did the slightly elevated concentration of urinary PAH metabolites correlate with airborne PAH exposure. CONCLUSION Miners' exposures to EC and NO2 were lower than those in older studies indicating the effect of sharpened emission legislation and new technologies. Using modern vehicles with diesel particulate filter (DPF) may have contributed to the lower ambient underground PM concentration and exposures. The semi-volatile behavior of the PAHs might have led to inefficient removal in the engines aftertreatment systems and delayed removal by the workplace ventilation system due to partitioning to indoor surfaces. The results indicate that secondary emissions can be an important source of gaseous PAH exposure in the mine.
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Affiliation(s)
- Louise Gren
- Ergonomics and Aerosol Technology, LTH, Lund University, 221 00 Lund, Sweden
| | - Annette M. Krais
- Division of Occupational and Environmental Medicine, Lund University, 221 00 Lund, Sweden
| | - Eva Assarsson
- Division of Occupational and Environmental Medicine, Lund University, 221 00 Lund, Sweden
| | - Karin Broberg
- Division of Occupational and Environmental Medicine, Lund University, 221 00 Lund, Sweden
| | - Malin Engfeldt
- Division of Occupational and Environmental Medicine, Lund University, 221 00 Lund, Sweden
- Department of Occupational and Environmental Medicine, Region Skåne, 223 81 Lund, Sweden
| | - Christian Lindh
- Division of Occupational and Environmental Medicine, Lund University, 221 00 Lund, Sweden
| | - Bo Strandberg
- Division of Occupational and Environmental Medicine, Lund University, 221 00 Lund, Sweden
- Department of Occupational and Environmental Medicine, Region Skåne, 223 81 Lund, Sweden
| | - Joakim Pagels
- Ergonomics and Aerosol Technology, LTH, Lund University, 221 00 Lund, Sweden
| | - Maria Hedmer
- Division of Occupational and Environmental Medicine, Lund University, 221 00 Lund, Sweden
- Department of Occupational and Environmental Medicine, Region Skåne, 223 81 Lund, Sweden
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