1
|
Banerjee B, Kundu S, Kanchan R, Mohanta A. Examining the relationship between atmospheric pollutants and meteorological factors in Asansol city, West Bengal, India, using statistical modelling. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024:10.1007/s11356-024-33608-z. [PMID: 38761262 DOI: 10.1007/s11356-024-33608-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2024] [Accepted: 05/04/2024] [Indexed: 05/20/2024]
Abstract
Meteorological conditions significantly impact ambient air quality in urban environments. This study focuses on Asansol, known as the "Coal City" and the "Industrial Heart of West Bengal," a notable hotspot for air pollution. Despite its significance, limited research has addressed the influence of meteorological factors on key air pollutants in this urban area. From January 2019 to December 2023, this investigation explores the relationships between meteorological parameters (including atmospheric temperature, relative humidity, rainfall, wind speed) and the concentrations of crucial air pollutants (PM2.5, PM10, NO2, SO2). Temporal trends in air pollutant concentrations are also analysed. The Spearman correlation method is used to establish associations between pollutant concentrations and meteorological variables, while multiple linear regression (MLR) models are employed to assess meteorological factors and potential impact on pollutant concentrations. The analysis reveals a decreasing trend in pollutant concentrations in Asansol. Temperature exhibits negative correlations with all pollutants in all seasons except for a positive correlation during the monsoon. Rainfall consistently displays significant negative correlations with pollutants in all seasons. Relative humidity is negatively correlated with pollutants in all seasons, and wind speed, except during the post-monsoon season, shows negative correlations with all pollutants. Linear models excel in predicting particulate matter concentrations but perform poorly in predicting gaseous contaminants. Accounting for seasonal fluctuations and meteorological parameters, this research enhances the accuracy of air pollution forecasting, contributing to a better understanding of air quality dynamics in Asansol and similar urban areas.
Collapse
Affiliation(s)
- Biplab Banerjee
- Department of Geography, Faculty of Science, The MS University Baroda, Vadodara, India, 390002.
| | - Sudipta Kundu
- Department of Geography, Faculty of Science, CSJM University of Kanpur, Kanpur, India
| | - Rolee Kanchan
- Department of Geography, Faculty of Science, The MS University Baroda, Vadodara, India, 390002
| | - Agradeep Mohanta
- Department of Botany, Faculty of Science, The MS University Baroda, Vadodara, 390002, India
| |
Collapse
|
2
|
Wang F, Xu Y, Patel PN, Gautam R, Gao M, Liu C, Ding Y, Chen H, Yang Y, Zhou Y, Carmichael GR, McElroy MB. Arctic amplification-induced decline in West and South Asia dust warrants stronger antidesertification toward carbon neutrality. Proc Natl Acad Sci U S A 2024; 121:e2317444121. [PMID: 38527208 PMCID: PMC10998603 DOI: 10.1073/pnas.2317444121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2023] [Accepted: 02/12/2024] [Indexed: 03/27/2024] Open
Abstract
Dust loading in West and South Asia has been a major environmental issue due to its negative effects on air quality, food security, energy supply and public health, as well as on regional and global weather and climate. Yet a robust understanding of its recent changes and future projection remains unclear. On the basis of several high-quality remote sensing products, we detect a consistently decreasing trend of dust loading in West and South Asia over the last two decades. In contrast to previous studies emphasizing the role of local land use changes, here, we attribute the regional dust decline to the continuous intensification of Arctic amplification driven by anthropogenic global warming. Arctic amplification results in anomalous mid-latitude atmospheric circulation, particularly a deepened trough stretching from West Siberia to Northeast India, which inhibits both dust emissions and their downstream transports. Large ensemble climate model simulations further support the dominant role of greenhouse gases induced Arctic amplification in modulating dust loading over West and South Asia. Future projections under different emission scenarios imply potential adverse effects of carbon neutrality in leading to higher regional dust loading and thus highlight the importance of stronger anti-desertification counter-actions such as reforestation and irrigation management.
Collapse
Affiliation(s)
- Fan Wang
- Department of Geography, Hong Kong Baptist University, Hong Kong SAR 999077, China
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA02138
| | - Yangyang Xu
- Department of Atmospheric Sciences, Texas A&M University, College Station, TX77843
- Environmental Defense Fund, Washington, DC20009
| | - Piyushkumar N. Patel
- Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109
- Oak Ridge Associated Universities, Oak Ridge, TN37830
| | | | - Meng Gao
- Department of Geography, Hong Kong Baptist University, Hong Kong SAR 999077, China
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA02138
| | - Cheng Liu
- Department of Precision Machinery and Precision Instrumentation, University of Science and Technology of China, Hefei230026, China
- Key Laboratory of Environmental Optics and Technology, Anhui Institute of Optics and Fine Mechanics, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei230031, China
| | - Yihui Ding
- National Climate Center, Chinese Meteorological Administration, Beijing100081, China
| | - Haishan Chen
- Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, School of Atmospheric Physics, Nanjing University of Information Science and Technology, Nanjing210044, China
| | - Yuanjian Yang
- Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters, School of Atmospheric Physics, Nanjing University of Information Science and Technology, Nanjing210044, China
| | - Yuyu Zhou
- Department of Geography and Institute for Climate and Carbon Neutrality, The University of Hong Kong, Hong Kong SAR999077, China
| | - Gregory R. Carmichael
- Department of Chemical and Biochemical Engineering, The University of Iowa, Iowa City, IA52242
| | - Michael B. McElroy
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA02138
| |
Collapse
|
3
|
Tariq S, Nisa A, Ul-Haq Z, Mariam A, Murshed M, Sulaymon ID, Salam MA, Mehmood U. Classification of aerosols using particle linear depolarization ratio (PLDR) over seven urban locations of Asia. CHEMOSPHERE 2024; 350:141119. [PMID: 38195014 DOI: 10.1016/j.chemosphere.2024.141119] [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: 08/05/2023] [Revised: 12/27/2023] [Accepted: 01/03/2024] [Indexed: 01/11/2024]
Abstract
Active lidar remote sensing has been used to obtain detailed and quantitative information about the properties of aerosols. We have analyzed the spatio-temporal classification of aerosols using the parameters of particle linear depolarization ratio and single scattering albedo from Aerosol Robotic Network (AERONET) over seven megacities of Asia namely; Lahore, Karachi, Kanpur, Pune, Beijing, Osaka, and Bandung. We find that pollution aerosols dominate during the winter season in all the megacities. The concentrations, however, vary concerning the locations, i.e., 70-80% pollution aerosols are present over Lahore, 40-50% over Karachi, 90-95% over Kanpur and Pune, 60-70% and over Beijing and Osaka. Pure Dust (PD), Pollution Dominated Mixture (PDM), and Dust Dominated Mixture (DDM) are found to be dominant during spring and summer seasons.This proposes that dust over Asia normally exists as a mixture with pollution aerosols instead of pure form. We also find that black carbon (BC) dominated pollution aerosols.
Collapse
Affiliation(s)
- Salman Tariq
- Department of Space Science, University of the Punjab, Lahore, Pakistan; Remote Sensing, GIS and Climatic Research Lab (National Center of GIS and Space Applications), Centre for Remote Sensing, University of the Punjab, Lahore, Pakistan.
| | - Aiman Nisa
- Department of Space Science, University of the Punjab, Lahore, Pakistan; Remote Sensing, GIS and Climatic Research Lab (National Center of GIS and Space Applications), Centre for Remote Sensing, University of the Punjab, Lahore, Pakistan
| | - Zia Ul-Haq
- Department of Space Science, University of the Punjab, Lahore, Pakistan; Remote Sensing, GIS and Climatic Research Lab (National Center of GIS and Space Applications), Centre for Remote Sensing, University of the Punjab, Lahore, Pakistan
| | - Ayesha Mariam
- Remote Sensing, GIS and Climatic Research Lab (National Center of GIS and Space Applications), Centre for Remote Sensing, University of the Punjab, Lahore, Pakistan
| | - Muntasir Murshed
- Department of Economics, School of Business and Economics, North South University, Dhaka, 1229, Bangladesh; Department of Journalism, Media and Communications, Daffodil International University, Dhaka, Bangladesh.
| | - Ishaq Dimeji Sulaymon
- Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control, Collaborative Innovation Center of Atmospheric Environment and Equipment Technology, School of Environmental Science and Engineering, Nanjing University of Information Science and Technology, Nanjing, 210044, China
| | - Mohammed Abdus Salam
- Department of Environmental Science and Disaster Management, Noakhali Science and Technology University, Noakhali, 3814, Bangladesh
| | - Usman Mehmood
- Remote Sensing, GIS and Climatic Research Lab (National Center of GIS and Space Applications), Centre for Remote Sensing, University of the Punjab, Lahore, Pakistan; Department of Business Administration, Bahçeşehir Cyprus University, Nicosia, Northern Cyprus, Turkey
| |
Collapse
|
4
|
Singh R, Singh V, Gautam AS, Gautam S, Sharma M, Soni PS, Singh K, Gautam A. Temporal and Spatial Variations of Satellite-Based Aerosol Optical Depths, Angstrom Exponent, Single Scattering Albedo, and Ultraviolet-Aerosol Index over Five Polluted and Less-Polluted Cities of Northern India: Impact of Urbanization and Climate Change. AEROSOL SCIENCE AND ENGINEERING 2023; 7:131-149. [PMCID: PMC9648442 DOI: 10.1007/s41810-022-00168-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/27/2022] [Revised: 10/25/2022] [Accepted: 10/31/2022] [Indexed: 05/31/2023]
Abstract
It is widely acknowledged that factors such as population growth, urbanization's quick speed, economic growth, and industrialization all have a role in the atmosphere's rising aerosol concentration. In the current work, we assessed and discussed the findings of a thorough analysis of the temporal and spatial variations of satellite-based aerosol optical parameters such as Aerosol Optical Depth (AOD), Angstrom Exponent (AE), Single Scattering Albedo (SSA), and Ultraviolet-Aerosol Index (UV-AI), and their concentration have been investigated in this study over five polluted and less-polluted cities of northern India during the last decade 2011–2020. The temporal variation of aerosol optical parameters for AOD ranging from 0.2 to 1.8 with decadal mean 0.86 ± 0.36 for Patna region shows high value with a decadal increasing trend over the study area due to rise in aerosols combustion of fossil fuels, huge vehicles traffic, and biomass over the past ten years. The temporal variation of AE ranging from 0.3 to 1.8 with decadal mean 1.72 ± 0.11 for Agra region shows high value as compared to other study areas, which indicates a comparatively higher level of fine-mode aerosols at Agra. The temporal variation of SSA ranging from 0.8 to 0.9 with decadal mean 0.92 ± 0.02 for SSA shows no discernible decadal pattern at any of the locations. The temporal variation of UV-AI ranging from -1.01 to 2.36 with decadal mean 0.59 ± 0.06 for UV-AI demonstrates a rising tendency, with a noticeable rise in Ludhiana, which suggests relative dominance of absorbing dust aerosols over Ludhiana. Further, to understand the impact of emerging activities, analyses were done in seasonality. For this aerosol climatology was derived for different seasons, i.e., Winter, Pre-Monsoon, Monsoon, and Post-Monsoon. High aerosol was observed in Winter for the study areas Patna, Delhi, and Agra which indicated the particles major dominance of burning aerosol from biomass; and the worst in Monsoon and Post-Monsoon for the Tehri Garhwal and Ludhiana study areas which indicated most of the aerosol concentration is removed by rainfall. After that, we analyzed the correlation among all the parameters to better understand the temporal and spatial distribution characteristics of aerosols over the selected region. The value of r for AOD (550 nm) for regions 2 and 1(0.80) shows a strong positive correlation and moderately positive for the regions 3 and 1 (0.64), mostly as a result of mineral dust carried from arid western regions. The value of r for AE (412/470 nm) for region 3 and (0.40) shows a moderately positive correlation, which is the resultant of the dominance of fine-mode aerosol and negative for the regions 5 and 1 (− 0.06). The value of r for SSA (500 nm) for regions 2 and 1 (0.63) shows a moderately positive correlation, which explains the rise in big aerosol particles, which scatters sun energy more efficiently, and the value of r for UV-AI for regions 1 and 2 shows a strong positive correlation (0.77) and moderately positive for the regions 3 and 1 (0.46) which indicates the absorbing aerosols present over the study region.
Collapse
Affiliation(s)
- Rolly Singh
- Department of Physics Agra College, Dr Bhimrao Ambedkar University, Agra, Agra, 282004 Uttar Pradesh India
| | - Vikram Singh
- Department of Physics Agra College, Dr Bhimrao Ambedkar University, Agra, Agra, 282004 Uttar Pradesh India
| | - Alok Sagar Gautam
- Department of Physics, Hemvati Nandan Bahuguna Garhwal University (A Central University), Srinagar, Garhwal, India
| | - Sneha Gautam
- Department of Civil Engineering, Karunya Institute of Technology and Sciences, Coimbatore, 641117 India
| | - Manish Sharma
- School of Science and Engineering, Himgiri Zee University, Dehra Dun, Uttarakhand India
| | - Pushpendra Singh Soni
- Department of Physics Agra College, Dr Bhimrao Ambedkar University, Agra, Agra, 282004 Uttar Pradesh India
| | - Karan Singh
- Department of Physics, Hemvati Nandan Bahuguna Garhwal University (A Central University), Srinagar, Garhwal, India
| | - Alka Gautam
- Department of Physics Agra College, Dr Bhimrao Ambedkar University, Agra, Agra, 282004 Uttar Pradesh India
| |
Collapse
|
5
|
Khatri P, Hayasaka T, Holben BN, Singh RP, Letu H, Tripathi SN. Increased aerosols can reverse Twomey effect in water clouds through radiative pathway. Sci Rep 2022; 12:20666. [PMID: 36450848 PMCID: PMC9712532 DOI: 10.1038/s41598-022-25241-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Accepted: 11/28/2022] [Indexed: 12/02/2022] Open
Abstract
Aerosols play important roles in modulations of cloud properties and hydrological cycle by decreasing the size of cloud droplets with the increase of aerosols under the condition of fixed liquid water path, which is known as the first aerosol indirect effect or Twomey-effect or microphysical effect. Using high-quality aerosol data from surface observations and statistically decoupling the influence of meteorological factors, we show that highly loaded aerosols can counter this microphysical effect through the radiative effect to result both the decrease and increase of cloud droplet size depending on liquid water path in water clouds. The radiative effect due to increased aerosols reduces the moisture content, but increases the atmospheric stability at higher altitudes, generating conditions favorable for cloud top entrainment and cloud droplet coalescence. Such radiatively driven cloud droplet coalescence process is relatively stronger in thicker clouds to counter relatively weaker microphysical effect, resulting the increase of cloud droplet size with the increase of aerosol loading; and vice-versa in thinner clouds. Overall, the study suggests the prevalence of both negative and positive relationships between cloud droplet size and aerosol loading in highly polluted regions.
Collapse
Affiliation(s)
- Pradeep Khatri
- grid.69566.3a0000 0001 2248 6943Center for Atmospheric and Oceanic Studies, Tohoku University, Sendai, Japan
| | - Tadahiro Hayasaka
- grid.69566.3a0000 0001 2248 6943Center for Atmospheric and Oceanic Studies, Tohoku University, Sendai, Japan
| | - Brent N. Holben
- grid.133275.10000 0004 0637 6666National Aeronautics and Space Administration, Goddard Space Flight Center, Greenbelt, USA
| | - Ramesh P. Singh
- grid.254024.50000 0000 9006 1798School of Life and Environmental Sciences, Schmid College of Science and Technology, Chapman University, Orange, CA USA
| | - Husi Letu
- grid.9227.e0000000119573309Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Beijing, China
| | - Sachchida N. Tripathi
- grid.417965.80000 0000 8702 0100Department of Civil Engineering, Indian Institute of Technology Kanpur, Kanpur, India
| |
Collapse
|
6
|
Filonchyk M, Peterson MP, Gusev A, Hu F, Yan H, Zhou L. Measuring air pollution from the 2021 Canary Islands volcanic eruption. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 849:157827. [PMID: 35944626 DOI: 10.1016/j.scitotenv.2022.157827] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/22/2022] [Revised: 07/16/2022] [Accepted: 07/31/2022] [Indexed: 06/15/2023]
Abstract
The eruption of the Cumbre Vieja volcano on the island of La Palma (Canary Islands, Spain) began on September 19, 2021 and ended on December 13, 2021. It lasted continuously for 85 days with short periods of calm when lava did not exit the cone of the volcano. Vast amounts of volcanic material, including ash and gases, were emitted into the environment. This research focuses on these emissions. The main objective is to use available open-source data to examine the impact on regional and local air quality. Data from the following sources were used: 1) Copernicus Atmosphere Monitoring Service (CAMS) data was used to track the transfer of volcanic SO2 in the troposphere in early October over long distances from the source of the eruption, including Western and Eastern Europe, across the Atlantic Ocean and the Caribbean; 2) Data from ground monitoring stations measured the concentrations of SO2 and PM10 near the source; 3) AErosol RObotic NETwork (AERONET) data from the La Palma station that showed high Aerosol Optical Depth (AOD) values (over 0.4) during the active phase of emissions on September 24 and 28, as well as on October 3; 4) Ångström Exponent (AE) values indicated the presence of particles of different sizes. On September 24, high AE values (>1.5), showed the presence of fine-mode fraction scattering aerosols such as sulfates; 5) Cloud Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) data additionally confirmed the presence of sulfate and dust aerosols in the atmosphere over the region. However, the influence of Saharan dust on the atmosphere of the entire region could not be excluded. This research helps forecast air pollution resulting from large-scale volcanic eruptions and associated health risks to humans.
Collapse
Affiliation(s)
- Mikalai Filonchyk
- Faculty of Geomatics, Lanzhou Jiaotong University, Lanzhou 730070, China; Gansu Provincial Engineering Laboratory for National Geographic State Monitoring, Lanzhou 730070, China.
| | - Michael P Peterson
- Department of Geography/Geology, University of Nebraska Omaha, Omaha, NE 68182, USA.
| | - Andrei Gusev
- Francisk Skorina Gomel State University, Gomel 246019, Belarus
| | - Fengning Hu
- Faculty of Geomatics, Lanzhou Jiaotong University, Lanzhou 730070, China; Gansu Provincial Engineering Laboratory for National Geographic State Monitoring, Lanzhou 730070, China
| | - Haowen Yan
- Faculty of Geomatics, Lanzhou Jiaotong University, Lanzhou 730070, China; Gansu Provincial Engineering Laboratory for National Geographic State Monitoring, Lanzhou 730070, China.
| | - Liang Zhou
- Faculty of Geomatics, Lanzhou Jiaotong University, Lanzhou 730070, China; Gansu Provincial Engineering Laboratory for National Geographic State Monitoring, Lanzhou 730070, China.
| |
Collapse
|
7
|
Bui TH, Nguyen DL, Nguyen HH. Study of aerosol optical properties at two urban areas in the north of Vietnam with the implication for biomass burning impacts. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:41923-41940. [PMID: 34328622 DOI: 10.1007/s11356-021-15608-5] [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: 04/01/2021] [Accepted: 07/20/2021] [Indexed: 06/13/2023]
Abstract
The spatiotemporal distribution and characterization of aerosol optical properties in the north of Vietnam were investigated extensively using the long-term measurements obtained from Moderate Resolution Imaging Spectroradiometer (MODIS) (from 2010 to 2019) and two Aerosol Robotic Network (AERONET) stations (Nghia Do, Hanoi City, from 2010 to 2019 and Son La from 2012 to 2019) located in fast-developing urban areas. This study also analyzed the tendency of AOD over different wavelengths as well as the influences of meteorological parameters and boundary layer height (BLH) on AOD and Ångström exponent (AE). The annual mean AOD500 at Nghia Do and Son La stations were 0.81 and 0.78, respectively. Our results revealed the existence of particles emitted from anthropogenic activities in Hanoi and Son La with the dominance of fine particles (more than 90% of the AE440-870 were larger than 1). Besides, a high percentage of AE440-870 larger than or approximately 1.5 during the dry and transition months in Son La indicated the existence of biomass-burning aerosol particles due to forest fires and burning of agriculture residuals. The classification results for aerosol types showed the presence of both biomass burning and urban/industrial aerosol types at Nghia Do and Son La sites. Among the investigated meteorological parameters, surface solar radiation expressed a significant correlation with AE440-870 in all three seasons at the two sites due to the secondary formation of fine particles induced by the high solar radiation condition. The impacts of meteorological parameters and BLH on AOD were not observed simultaneously during three seasons at Nghia Do and Son La stations.
Collapse
Affiliation(s)
- Thi Hieu Bui
- Faculty of Environmental Engineering, National University of Civil Engineering, Hanoi, Vietnam
| | - Duc Luong Nguyen
- Faculty of Environmental Engineering, National University of Civil Engineering, Hanoi, Vietnam.
| | - Hoang Hiep Nguyen
- Graduate Institute of Applied Geology, National Central University, Taoyuan, 32000, Taiwan
| |
Collapse
|
8
|
The Effects of Local Pollution and Transport Dust on Aerosol Properties in Typical Arid Regions of Central Asia during DAO-K Measurement. ATMOSPHERE 2022. [DOI: 10.3390/atmos13050729] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Dust aerosol has an impact on both the regional radiation balance and the global radiative forcing estimation. The Taklimakan Desert is the focus of the present research on the optical and micro-physical characteristics of the dust aerosol characteristics in Central Asia. However, our knowledge is still limited regarding this typical arid region. The DAO-K (Dust Aerosol Observation-Kashgar) campaign in April 2019 presented a great opportunity to understand further the effects of local pollution and transported dust on the optical and physical characteristics of the background aerosol in Kashgar. In the present study, the consistency of the simultaneous observations is tested, based on the optical closure method. Three periods dominated by the regional background dust (RBD), local polluted dust (LPD), and Taklimakan transported dust (TTD), are identified through the backward trajectories, combined with the dust scores from AIRS (Atmospheric Infrared Sounder). The variations of the optical and micro-physical properties of dust aerosols are then studied, while a direct comparison of the total column and near surface is conducted. Generally, the mineral dust is supposed to be primarily composed of silicate minerals, which are mostly very weakly absorbing in the visible spectrum. Although there is very clean air (with PM2.5 of 21 μg/m3), a strong absorption (with an SSA of 0.77, AAE of 1.62) is still observed during the period dominated by the regional background dust aerosol. The near-surface observations show that there is PM2.5 pollution of ~98 μg/m3, with strong absorption in the Kashgar site during the whole observation. Local pollution can obviously enhance the absorption (with an SSA of 0.72, AAE of 1.58) of dust aerosol at the visible spectrum. This is caused by the increase in submicron fine particles (such as soot) with effective radii of 0.14 μm, 0.17 μm, and 0.34 μm. The transported Taklimakan dust aerosol has a relatively stable composition and strong scattering characteristics (with an SSA of 0.86, AAE of ~2.0). In comparison to the total column aerosol, the near-surface aerosol has the smaller size and the stronger absorption. Moreover, there is a very strong scattering of the total column aerosol. Even the local emission with the strong absorption has a fairly minor effect on the total column SSA. The comparison also shows that the peak radii of the total column PVSD is nearly twice as high as that of the near-surface PVSD. This work contributes to building a relationship between the remote sensing (total column) observations and the near-surface aerosol properties, and has the potential to improve the accuracy of the radiative forcing estimation in Kashgar.
Collapse
|
9
|
Retrieval of Black Carbon Absorption Aerosol Optical Depth from AERONET Observations over the World during 2000–2018. REMOTE SENSING 2022. [DOI: 10.3390/rs14061510] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/10/2022]
Abstract
Black carbon (BC) absorption aerosol optical depth (AAODBC) defines the contribution of BC in light absorption and is retrievable using sun/sky radiometer measurements provided by Aerosol Robotic Network (AERONET) inversion products. In this study, we utilized AERONET-retrieved depolarization ratio (DPR, δp), single scattering albedo (SSA, ω), and Ångström Exponent (AE, å) of version 3 level 2.0 products as indicators to estimate the contribution of BC to the absorbing fractions of AOD. We applied our methodology to the AERONET sites, including North and South America, Europe, East Asia, Africa, India, and the Middle East, during 2000–2018. The long-term AAODBC showed a downward tendency over Sao Paulo (−0.001 year−1), Thessaloniki (−0.0004 year−1), Beijing (−0.001 year−1), Seoul (−0.0015 year−1), and Cape Verde (−0.0009 year−1) with the highest values over the populous sites. This declining tendency in AAODBC can be attributable to the successful emission control policies over these sites, particularly in Europe, America, and China. The AAODBC at the Beijing, Sao Paulo, Mexico City, and the Indian sites showed a clear seasonality indicating the notable role of residential heating in BC emissions over these sites during winter. We found a higher correlation between AAODBC and fine mode AOD at 440 nm at all sites except for Beijing. High pollution episodes, BC emission from different sources, and aggregation properties seem to be the main drivers of higher AAODBC correlation with coarse particles over Beijing.
Collapse
|
10
|
Jnanesh SP, Lal DM, Gopalakrishnan V, Ghude SD, Pawar SD, Tiwari S, Srivastava MK. Lightning Characteristics Over Humid Regions and Arid Regions and Their Association With Aerosols Over Northern India. PURE AND APPLIED GEOPHYSICS 2022; 179:1403-1419. [PMID: 35250099 PMCID: PMC8883017 DOI: 10.1007/s00024-022-02981-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 02/10/2022] [Accepted: 02/10/2022] [Indexed: 06/14/2023]
Abstract
UNLABELLED The association between aerosol and lightning has been investigated with long-term decadal data (2005-2014) for lightning, aerosol optical depth (AOD), relative humidity, and effective cloud droplet size. To understand the complex relationship between aerosol and lightning, two different regions with different climatic and weather conditions, a humid region R1 (22°-29° N, 89°-92° E) and an arid region R2 (23°-28° N, 70°-76° E) of northern India, were chosen for the study domain. The results show that lightning activity was observed to occur more over the humid region R1, i.e., 1141 days (1/3 of total days), than over the arid region R2, i.e., 740 days (1/5 of total days). Also, over the humid region R1, the highest lightning flash density was recorded as nearly 4.6 × 10-4 flashes/km2/day observed for 18 days (1.5%); on the contrary, over the arid region R2, the maximum lightning flash density was observed to be 2.5 × 10-4 flashes/km2/day and occurred for about 22 days (2.9%). The analysis shows that a nonlinear relationship exists between aerosol and lightning with a highly associated influence of relative humidity. A very significant positive and negative co-relation that varies with relative humidity has been observed between AOD and lightning for both humid and arid regions. This shows relative humidity is the key factor in determining the increase or decrease of lightning activity. This study also shows that the larger the cloud droplet size, the higher the relative humidity and vice versa. This study emphasizes that aerosol concentration in the atmosphere influences cloud microphysics by modulating the size of cloud droplets and thereby regulating the lightning frequency. The atmospheric humidity is the driving factor in deciding the positive or negative co-relationship between aerosol and lightning. SUPPLEMENTARY INFORMATION The online version contains supplementary material available at 10.1007/s00024-022-02981-6.
Collapse
Affiliation(s)
- S. P. Jnanesh
- Indian Institute of Tropical Meteorology, Pune, India
- Department of Geophysics, Banaras Hindu University, Varanasi, India
| | - D. M. Lal
- Indian Institute of Tropical Meteorology, Pune, India
| | | | | | | | - S. Tiwari
- Indian Institute of Tropical Meteorology, Pune, India
| | | |
Collapse
|
11
|
Aerosol Characteristics and Their Impact on the Himalayan Energy Budget. SUSTAINABILITY 2021. [DOI: 10.3390/su14010179] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The extensive work on the increasing burden of aerosols and resultant climate implications shows a matter of great concern. In this study, we investigate the aerosol optical depth (AOD) variations in the Indian Himalayan Region (IHR) between its plains and alpine regions and the corresponding consequences on the energy balance on the Himalayan glaciers. For this purpose, AOD data from Moderate Resolution Imaging Spectroradiometer (MODIS, MOD-L3), Aerosol Robotic Network (AERONET), India, and Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) were analyzed. Aerosol radiative forcing (ARF) was assessed using the atmospheric radiation transfer model (RTM) integrated into AERONET inversion code based on the Discrete Ordinate Radiative Transfer (DISORT) module. Further, air mass trajectory over the entire IHR was analyzed using a hybrid Single-Particle Lagrangian Integrated Trajectory (HYSPLIT) model. We estimated that between 2001 and 2015, the monthly average ARF at the surface (ARFSFC), top of the atmosphere (ARFTOA), and atmosphere (ARFATM) were −89.6 ± 18.6 Wm−2, −25.2 ± 6.8 Wm−2, and +64.4 ± 16.5 Wm−2, respectively. We observed that during dust aerosol transport days, the ARFSFC and TOA changed by −112.2 and −40.7 Wm−2, respectively, compared with low aerosol loading days, thereby accounting for the decrease in the solar radiation by 207% reaching the surface. This substantial decrease in the solar radiation reaching the Earth’s surface increases the heating rate in the atmosphere by 3.1-fold, thereby acting as an additional forcing factor for accelerated melting of the snow and glacier resources of the IHR.
Collapse
|
12
|
Yadav K, Rao VD, Sridevi B, Sarma VVSS. Decadal variations in natural and anthropogenic aerosol optical depth over the Bay of Bengal: the influence of pollutants from Indo-GangeticPlain. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:55202-55219. [PMID: 34129167 DOI: 10.1007/s11356-021-14703-x] [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: 12/29/2020] [Accepted: 05/31/2021] [Indexed: 06/12/2023]
Abstract
Perennial increase in atmospheric pollution over the Bay of Bengal (BoB) and South China Sea is reported due to increase in human population and industrial activity in South and Southeast Asia. Based on total aerosol optical depth (AOD) derived from MODIS (moderate resolution imaging resolution imaging spectroradiometer), natural and anthropogenic fractions were derived. The seasonality and spatial variability in rate of increase in total, natural, and anthropogenic AOD fractions were examined over the BoB using data collected between 2001 and 2019. Both total and anthropogenic AOD displayed statistically significant rate of increase in the northwest BoB (NWB) and western coastal BoB (WCB) regions during 2001 to 2019 whereas the long-term changes are insignificant in the other regions of BoB. Significant increase in AOD in the NWB and WCB regions is mainly contributed by dominant outflow of anthropogenic emissions from Indo-Gangetic Plain (IGP) area of Indian subcontinent. The magnitude of AOD decreased by half from northern BoB to equatorial region due to increase in distance from the source region. The contribution of anthropogenic AOD was >70% to total AOD with higher contribution during winter and lower during summer. The rate of increase in both total and anthropogenic AOD was close to 0.104 and 0.099 per decade in the NWB and 0.069 and 0.059 per decade in the WCB region between 2001 and 2019. The rate of increase in total and anthropogenic AOD decreased from 2001-2009 (0.164 and 0.115 per decade respectively) to 2010-2019 (0.068 and 0.076 per decade respectively) in the NWB region. Significant increase in anthropogenic AOD by 50 and 30% was observed during El Niño and La Niña periods respectively than normal year in both northwest BoB (NWB) and western coastal (WCB) regions due to change in strength and direction of winds. Although some fraction of anthropogenic AOD is found over the entire BoB, significant rate of increase in anthropogenic AOD is found only about 23% of the area of BoB than hitherto reported as entire BoB. The impact of atmospheric deposition of anthropogenic aerosols on biogeochemical processes, such as primary production and ocean acidification, needs further evaluation.
Collapse
Affiliation(s)
- K Yadav
- CSIR-National Institute of Oceanography, 176 Lawsons Bay Colony, Visakhapatnam, 530017, India
| | - V D Rao
- ESSO-National Centre for Coastal Research, Chennai, India
| | - B Sridevi
- CSIR-National Institute of Oceanography, 176 Lawsons Bay Colony, Visakhapatnam, 530017, India
| | - V V S S Sarma
- CSIR-National Institute of Oceanography, 176 Lawsons Bay Colony, Visakhapatnam, 530017, India.
- Academy of Scientific and Innovative Research, Dona Paula, Goa, India.
| |
Collapse
|
13
|
Singh T, Ravindra K, Sreekanth V, Gupta P, Sembhi H, Tripathi SN, Mor S. Climatological trends in satellite-derived aerosol optical depth over North India and its relationship with crop residue burning: Rural-urban contrast. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 748:140963. [PMID: 32814282 DOI: 10.1016/j.scitotenv.2020.140963] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Revised: 06/15/2020] [Accepted: 07/12/2020] [Indexed: 06/11/2023]
Abstract
Columnar Aerosol Optical Depths (AOD) over an urban area (Chandigarh) and a rural area (Khera, Fatehgarh Sahib district) situated in the Indo-Gangetic Plains (IGP) of India were analysed to study their temporal heterogeneity in terms of interannual, seasonal and monthly variations. Over the last few decades, IGP has become one of the global hotspots of air pollution due to the increased anthropogenic activities such as traffic, industries, agricultural waste burning etc. Level-2 AODs (550 nm) were retrieved from the Moderate Resolution Imaging Spectroradiometer (MODIS) sensors onboard NASA's Terra and Aqua satellites, for a period of 14 years (2005-2018). The climatological mean Terra-MODIS (Aqua-MODIS) AOD over the urban location was ~0.497 ± 0.238 (0.474 ± 0.228), whereas over the rural location it was 0.542 ± 0.269 (0.534 ± 0.282). Linear trend analysis estimated an increase in annual mean Terra-MODIS (Aqua-MODIS) AOD at a rate of ~0.009 (0.013) per year over the urban site; whereas over the rural location the rate of increase was ~0.003 (0.004) per year. Results show that the observed increase is ~1.49% (2.41%) of climatological mean AOD over the urban location for Terra-MODIS (Aqua-MODIS), whereas, over the rural location, it was ~0.50% (0.67%). Using the HYSPLIT trajectory model, it was concluded that, during post-monsoon, the observed high AODs can be related to massive crop residue burning in the IGP region. These AOD trends can also be used to track the regional anthropogenic air-pollution changes. An empirical relation between AOD and PM10 was established, which can be used to estimate PM10 over the urban and rural areas of IGP (using MODIS AODs), complementing the sparse ground-based monitoring. Further, satellite-based air pollution data can be used for baseline assessment and understanding the impact of control policies such as National Clean Air Programme and to support formulate evidence-based pollution control strategies.
Collapse
Affiliation(s)
- Tanbir Singh
- Department of Environment Studies, Panjab University, Chandigarh 160014, India
| | - Khaiwal Ravindra
- Department of Community Medicine and School of Public Health, Post Graduate Institute of Medical Education & Research (PGIMER), Chandigarh, 160012, India.
| | - V Sreekanth
- Center for Study of Science, Technology & Policy, Bengaluru 560094, India
| | - Pawan Gupta
- Universities Space Research Association, Columbia, MD 21044, USA; NASA Marshall Space Flight Center, Huntsville, AL 35806, USA
| | - Harjinder Sembhi
- Earth Observation Science, School of Physics and Astronomy, University of Leicester, University Road, Leicester LE1 7RH, UK
| | - Sachchida Nand Tripathi
- Department of Civil Engineering, Centre for Environmental Science and Engineering, Indian Institute of Technology Kanpur, Kanpur 208016, India
| | - Suman Mor
- Department of Environment Studies, Panjab University, Chandigarh 160014, India.
| |
Collapse
|
14
|
Jing F, Singh RP. Optical properties of dust and crop burning emissions over India using ground and satellite data. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 718:134476. [PMID: 31843314 DOI: 10.1016/j.scitotenv.2019.134476] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/07/2019] [Revised: 09/09/2019] [Accepted: 09/14/2019] [Indexed: 06/10/2023]
Abstract
Dust storms during the pre-monsoon season (April-June) and crop residual burning events during the post-monsoon season (mid-October-mid-November) are common every year over the Indo-Gangetic plains (IGP). In this paper, we have compared dust storm and crop burning aerosols characteristics for the years 2016, 2017 and 2018 using ground and satellite data. CALIPSO data show that dust layers extended from the ground upto an altitude of about 5 km and the smoke from crop burning upto the height of 2 km. Characteristics of dust and crop burning aerosols show pronounced difference based on Kanpur AERONET data. Dominance of coarse particles (0.6-15 μm) during dust storms (pre-monsoon season), while fine particles (0.05-0.6 μm) dominate during crop residual burning. The spectral variations of single scattering albedo (SSA) during dusty days and crop burning days show low and high fractions of anthropogenic aerosols. We have also observed the impact of dust particles on Himalayan snow (cover, albedo and reflectance) and meteorological parameters (relative humidity and water vapor) on the surface and lower atmosphere using MODIS data and AIRS data at different pressure levels. Pronounced aerosols behaviors of the crop residual burning event coincided with Diwali festival on 30-31 October 2016 were observed. Our detailed analysis combining ground and satellite observations provides better understanding of aerosol optical and microphysical properties of dust storms and crop residual burnings. The results will be valuable in monitoring surrounding environment, identifying the emission source and dynamics of dust storms and crop burning emissions over India, especially in the IGP.
Collapse
Affiliation(s)
- Feng Jing
- Institute of Earthquake Forecasting, China Earthquake Administration, Beijing 100036, China; School of Life and Environmental Sciences, Schmid College of Science and Technology, Chapman University, Orange, CA 92866, USA.
| | - Ramesh P Singh
- School of Life and Environmental Sciences, Schmid College of Science and Technology, Chapman University, Orange, CA 92866, USA.
| |
Collapse
|
15
|
Spatiotemporal Trends of Aerosols over Urban Regions in Pakistan and Their Possible Links to Meteorological Parameters. ATMOSPHERE 2020. [DOI: 10.3390/atmos11030306] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Aerosol optical depth (AOD) has become one of the most crucial parameters for climate change assessment on regional and global scales. The present study investigates trends in AOD using long-term data derived from moderate resolution imaging spectro-radiometer (MODIS) over twelve regions in Pakistan. Different statistical tests are used to assess the annual and seasonal trends in AOD. Results reveal increasing AOD trends over most of the selected regions with an obvious increase over the north and northeastern parts of the study area. Annually, increasing trends (0.0002–0.0047 year−1) were observed over seven regions, with three being statistically significant. All the selected regions experience increasing AOD trends during the winter season with six being statistically significant while during the summer season seven regions experience increasing AOD trends and the remaining five exhibit the converse with two being statistically significant. The changes in the sign and magnitude of AOD trends have been attributed to prevailing meteorological conditions. The decreasing rainfall and increasing temperature trends mostly support the increasing AOD trend over the selected regions. The high/low AOD phases during the study period may be ascribed to the anomalies in mid-tropospheric relative humidity and wind fields. The summer season is generally characterized by high AOD with peak values observed over the regions located in central plains, which can be attributed to the dense population and enhanced concentration of industrial and vehicular emissions over this part of the study area. The results derived from the present study give an insight into aerosol trends and could form the basis for aerosol-induced climate change assessment over the study area.
Collapse
|
16
|
Singh RP, Chauhan A. Impact of lockdown on air quality in India during COVID-19 pandemic. AIR QUALITY, ATMOSPHERE, & HEALTH 2020; 13:921-928. [PMID: 32837613 PMCID: PMC7338669 DOI: 10.1007/s11869-020-00863-1] [Citation(s) in RCA: 72] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/26/2020] [Accepted: 06/23/2020] [Indexed: 05/18/2023]
Abstract
First time in India, total lockdown was announced on 22 March 2020 to stop the spread of COVID-19 and the lockdown was extended for 21 days on 24 March 2020 in the first phase. During the total lockdown, most of the sources for poor air quality were stopped in India. In this paper, we present an analysis of air quality (particulate matter-PM2.5, Air Quality Index, and tropospheric NO2) over India using ground and satellite observations. A pronounced decline in PM2.5 and AQI (Air Quality Index) is observed over Delhi, Mumbai, Hyderabad, Kolkata, and Chennai and also a declining trend was observed in tropospheric NO2 concentration during the lockdown period in 2020 compared with the same period in the year 2019. During the total lockdown period, the air quality has improved significantly which provides an important information to the cities' administration to develop rules and regulations on how they can improve air quality.
Collapse
Affiliation(s)
- Ramesh P. Singh
- School of Life and Environmental Sciences, Schmid College of Science and Technology, Chapman University, Orange, CA 92866 USA
| | - Akshansha Chauhan
- Formerly with Department of Environmental Science, Sharda University, Greater Noida, 201310 India
| |
Collapse
|
17
|
Khan R, Kumar KR, Zhao T. The climatology of aerosol optical thickness and radiative effects in Southeast Asia from 18-years of ground-based observations. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2019; 254:113025. [PMID: 31419660 DOI: 10.1016/j.envpol.2019.113025] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2019] [Revised: 07/25/2019] [Accepted: 08/04/2019] [Indexed: 06/10/2023]
Abstract
The present study utilizes 18 years of long-term (2001-2018) data collected from six active AERONET sites over the Indo-Gangetic Plain (IGP) and the North China Plain (NCP) areas in Southeast Asia. The annual mean (±SD) aerosol optical thickness at 440 nm (AOT440) was found high at XiangHe (0.92 ± 0.69) and Taihu (0.90 ± 0.51) followed by Beijing (0.81 ± 0.69), Lahore (0.81 ± 0.43), and Kanpur (0.73 ± 0.35) and low at Karachi (0.52 ± 0.23). Seasonally, high AOT440 with corresponding high Ångström exponent (ANG440-870) noticed during JJA for all sites, except Kanpur, suggesting the dominance of fine-mode particles, generally associated with large anthropogenic emissions. Climatologically, an increasing (decreasing) trend was observed over IGP (NCP) sites, with the highest (lowest) percentage of departures in AOT440 found over Beijing (Karachi). We further identified major aerosol types which showed the dominance of biomass burning, urban-industrial followed by the mixed type of aerosols. In addition, single scattering albedo (SSA), asymmetry parameter (ASP), volume size distribution (VSD), and complex aerosol refractive index (RI) showed significant temporal and spectral changes, illustrating the complexity of aerosol types. At last, the annual mean direct aerosol radiative forcing at the top, bottom, and within the atmosphere for all sites were found in the range from -17.36 ± 3.75 to -45.17 ± 4.87 W m-2, -64.6 ± 4.86 to -93.7 ± 10.27 W m-2, and 40.5 ± 6.43 to 68.25 ± 7.26 W m-2, respectively, with an averaged atmospheric heating rate of 0.9-2.3 K day-1. A large amount of anthropogenic aerosols showed a significant effect of heating (cooling) on the atmosphere (surface) results obviously, due to an increased rate of atmospheric heating. Therefore, the thermodynamic effects of anthropogenic aerosols on the atmospheric circulation and its structure should be taken into consideration for future study over the experimental sites.
Collapse
Affiliation(s)
- Rehana Khan
- Collaborative Innovation Centre on Forecast and Evaluation of Meteorological Disasters, Key Laboratory of Meteorological Disaster, Ministry of Education (KLME), International Joint Laboratory on Climate and Environment Change (ILCEC), Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, School of Atmospheric Physics, Nanjing University of Information Science and Technology, Nanjing 210044, Jiangsu, China; Department of Physics, Higher Education, Government of Khyber Pakhtunkhwa, Peshawar, 25000, Pakistan
| | - Kanike Raghavendra Kumar
- Collaborative Innovation Centre on Forecast and Evaluation of Meteorological Disasters, Key Laboratory of Meteorological Disaster, Ministry of Education (KLME), International Joint Laboratory on Climate and Environment Change (ILCEC), Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, School of Atmospheric Physics, Nanjing University of Information Science and Technology, Nanjing 210044, Jiangsu, China; Department of Physics, School of Sciences and Humanities, Green Fields Campus, K. L. University, Vaddeswaram 522502, Guntur, Andhra Pradesh, India.
| | - Tianliang Zhao
- Collaborative Innovation Centre on Forecast and Evaluation of Meteorological Disasters, Key Laboratory of Meteorological Disaster, Ministry of Education (KLME), International Joint Laboratory on Climate and Environment Change (ILCEC), Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, School of Atmospheric Physics, Nanjing University of Information Science and Technology, Nanjing 210044, Jiangsu, China.
| |
Collapse
|
18
|
Zeb B, Alam K, Sorooshian A, Chishtie F, Ahmad I, Bibi H. Temporal characteristics of aerosol optical properties over the glacier region of northern Pakistan. JOURNAL OF ATMOSPHERIC AND SOLAR-TERRESTRIAL PHYSICS 2019; 186:35-46. [PMID: 33911973 PMCID: PMC8078013 DOI: 10.1016/j.jastp.2019.02.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/14/2023]
Abstract
Glacier melting due to light-absorbing aerosol has become a growing issue in recent decades. The emphasis of this study is to examine aerosol loadings over the high mountain glacier region of northern Pakistan between 2004 and 2016, with sources including local emissions and long-range transported pollution. Optical properties of aerosols were seasonally analyzed over the glacier region (35-36.5°N; 74.5-77.5°E) along with three selected sites (Gilgit, Skardu, and Diamar) based on the Ozone Monitoring Instrument (OMI). The aerosol sub-type profile was analyzed with Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO). Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model was used to understand the origin of air masses arriving in the study region. The highest values of aerosol optical depth (AOD) and single scattering albedo (SSA) occurred during spring, whereas aerosol index (AI) and absorption AOD (AAOD) exhibited maximum values in winter and summer, respectively. The minimum values of AOD, AI, AAOD, and SSA occurred in winter, autumn, winter, and autumn, respectively. The results revealed that in spring and summer the prominent aerosols were dust, whereas, in autumn and winter, anthropogenic aerosols were prominent. Trend analysis showed that AI, AOD, and AAOD increased at the rate of 0.005, 0.006, and 0.0001 yr-1, respectively, while SSA decreased at the rate of 0.0002 yr-1. This is suggestive of the enhancement in aerosol types over the region with time that accelerates melting of ice. CALIPSO data indicate that the regional aerosol was mostly comprised of sub-types categorized as dust, polluted dust, smoke, and clean continental. The types of aerosols defined by OMI were in good agreement with CALIPSO retrievals. Analysis of the National Oceanic and Atmospheric Administration Hybrid Single Particle Lagrangian Integrated Trajectory (HYSPLIT) model revealed that air parcels arriving at the glacier region stemmed from different source sites.
Collapse
Affiliation(s)
- Bahadar Zeb
- Department of Physics, University of Malakand, Khyber Pakhtunkhwa, Pakistan
- Department of Mathematics, Shaheed Benazir Bhutto University, Sheringal, Dir Upper, Khyber Pakhtunkhwa, Pakistan
| | - Khan Alam
- Department of Physics, University of Peshawar, Khyber Pakhtunkhwa, Pakistan
- Corresponding author. (K. Alam)
| | - Armin Sorooshian
- Department of Chemical and Environmental Engineering, University of Arizona, Tucson, AZ, USA
- Department of Hydrology and Atmospheric Sciences, University of Arizona, Tucson, AZ, USA
| | - Farrukh Chishtie
- SERVIR-Mekong, Asian Disaster Preparedness Centre (ADPC), Bangkok, Thailand
| | - Ifthikhar Ahmad
- Department of Physics, University of Malakand, Khyber Pakhtunkhwa, Pakistan
| | - Humera Bibi
- Department of Physics, University of Peshawar, Khyber Pakhtunkhwa, Pakistan
| |
Collapse
|
19
|
Lone A, Jeelani G, Deshpande RD, Kang S, Huang J. Hydrochemical assessment (major ions and Hg) of meltwater in high altitude glacierized Himalayan catchment. ENVIRONMENTAL MONITORING AND ASSESSMENT 2019; 191:213. [PMID: 30852667 DOI: 10.1007/s10661-019-7338-y] [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: 08/30/2018] [Accepted: 02/18/2019] [Indexed: 06/09/2023]
Abstract
Snowpack and glacial melt samples were collected to understand the hydrochemical, isotopic characteristics and the source of Hg contamination in high altitude glacierized Himalayan catchment. Both the snow and glacial melt were acidic in nature with calcium and magnesium as the dominant cations and bicarbonate and chloride as the dominant anions. The major ion concentrations for cations were found to be Ca2+ > Mg2+ > Na+ > K+ and HCO3- > Cl- > SO42- > NO3- for anions. The atmospheric processes like the precipitation source and aerosol scavenging control the snow chemistry and the weathering of the rocks modify the hydrochemistry of glacial melt. The samples of both the snow and glacial melt were classified as Ca-Mg-HCO3- type. The concentration of Hg in snow (154.95 ng L-1) and glacial melt (112.04 ng L-1) was highest (still lower compared to the maximum permissible limit (1000 ng L-1) by WHO in drinking water) during summer season (August-September) and lowest (snow 2.2 and 40.01 ng L-1 for glacial melt) during winter (November). The results reveal that mercury concentration in snowpacks is attributed to the combined mixing of long-range transport of pollutants via westerlies throughout the year and the industrial effluents coming from highly industrial belts of Panjab, Haryana, Rajasthan, Indo-Gangetic plains, and neighboring areas via southwest monsoons during August-September. However, in glacial melt, the Hg concentration was typically controlled by rate of melting, leaching, and percolation. Higher degree and rate of glacial melting decreases the Hg concentration in glacial melt. Stable isotopic analysis and backward air mass trajectory modeling also corroborate the source of precipitation from southwest monsoons during August-September, with its air mass trajectories passing through the highly industrialized belts of Indo-Gangetic plain and adjoining areas.
Collapse
Affiliation(s)
- Altaf Lone
- Department of Earth Sciences, University of Kashmir, Srinagar, 190006, India
| | - G Jeelani
- Department of Earth Sciences, University of Kashmir, Srinagar, 190006, India.
| | | | - Shichang Kang
- State Key Laboratory of Cryospheric Science, Northwest Institute of Eco-environment and Resources, Chinese Academy of Sciences, Lanzhou, 730000, China
- CAS Center for Excellence in Tibetan Plateau Earth Sciences, Beijing, 100085, China
| | - Jie Huang
- CAS Center for Excellence in Tibetan Plateau Earth Sciences, Beijing, 100085, China
- Key Laboratory of Tibetan Environment Changes and Land Surface Processes, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, 100101, China
| |
Collapse
|
20
|
Sarkar S, Chauhan A, Kumar R, Singh RP. Impact of Deadly Dust Storms (May 2018) on Air Quality, Meteorological, and Atmospheric Parameters Over the Northern Parts of India. GEOHEALTH 2019; 3:67-80. [PMID: 32159032 PMCID: PMC7007138 DOI: 10.1029/2018gh000170] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2018] [Revised: 01/20/2019] [Accepted: 02/22/2019] [Indexed: 05/20/2023]
Abstract
The northern part of India, adjoining the Himalaya, is considered as one of the global hot spots of pollution because of various natural and anthropogenic factors. Throughout the year, the region is affected by pollution from various sources like dust, biomass burning, industrial and vehicular pollution, and myriad other anthropogenic emissions. These sources affect the air quality and health of millions of people who live in the Indo-Gangetic Plains. The dust storms that occur during the premonsoon months of March-June every year are one of the principal sources of pollution and originate from the source region of Arabian Peninsula and the Thar desert located in north-western India. In the year 2018, month of May, three back-to-back major dust storms occurred that caused massive damage, loss of human lives, and loss to property and had an impact on air quality and human health. In this paper, we combine observations from ground stations, satellites, and radiosonde networks to assess the impact of dust events in the month of May 2018, on meteorological parameters, aerosol properties, and air quality. We observed widespread changes associated with aerosol loadings, humidity, and vertical advection patterns with displacements of major trace and greenhouse gasses. We also notice drastic changes in suspended particulate matter concentrations, all of which can have significant ramifications in terms of human health and changes in weather pattern.
Collapse
Affiliation(s)
- Sudipta Sarkar
- NASA Goddard Space Flight CenterGreenbeltMDUSA
- Science Systems and Applications Inc.LanhamMDUSA
| | - Akshansha Chauhan
- Department of Environment Science, School of Basic Sciences and ResearchSharda UniversityGreater NoidaIndia
| | - Rajesh Kumar
- Department of Environment Science, School of Basic Sciences and ResearchSharda UniversityGreater NoidaIndia
| | - Ramesh P. Singh
- School of Life and Environmental Sciences, Schmid College of Science and TechnologyChapman UniversityOrangeCAUSA
| |
Collapse
|
21
|
Tiwari S, Kaskaoutis D, Soni VK, Dev Attri S, Singh AK. Aerosol columnar characteristics and their heterogeneous nature over Varanasi, in the central Ganges valley. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:24726-24745. [PMID: 29923051 DOI: 10.1007/s11356-018-2502-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/23/2017] [Accepted: 06/04/2018] [Indexed: 06/08/2023]
Abstract
The Indo-Gangetic Basin (IGB) experiences one of the highest aerosol loading over the globe with pronounced inter-/intra-seasonal variability. Four-year (January 2011-December 2014) continuous MICROTOPS-II sun-photometer measurements at Varanasi, central Ganges valley, provide an opportunity to investigate the aerosol physical and optical properties and their variability. A large variation in aerosol optical depth (AOD: from 0.23 to 1.89, mean of 0.82 ± 0.31) and Ångström exponent (AE: from 0.19 to 1.44, mean of 0.96 ± 0.27) is observed, indicating a highly turbid atmospheric environment with significant heterogeneity in aerosol sources, types and optical properties. The highest seasonal means of both AOD and AE are observed in the post-monsoon (October-November) season (0.95 ± 0.31 for AOD and 1.16 ± 0.14 for AE) followed by winter (December, January, February; 0.97 ± 0.34 for AOD and 1.09 ± 0.20 for AE) and are mainly attributed to the accumulation of aerosols from urban and biomass/crop residue burning emissions within a shallow boundary layer. In contrast, during the pre-monsoon and monsoon seasons, the aerosols are mostly coming from natural origin (desert and mineral dust) mixed with pollution in several cases. The spectral dependence of AE, the aerosol "curvature" effect and other graphical techniques are used for the identification of the aerosol types and their mixing processes in the atmosphere. Furthermore, the aerosol source-apportionment assessment using the weighted potential source contribution function (WPSCF) analysis reveals the different aerosol types, emission sources and transport pathways.
Collapse
Affiliation(s)
- Shani Tiwari
- Atmospheric Research Laboratory, Department of Physics, Banaras Hindu University, Varanasi, 221005, India
- Present Address: Graduate School of Environmental Studies, Nagoya University, Nagoya, Japan
| | - Dimitris Kaskaoutis
- Atmospheric Research Team, Institute for Environmental Research and Sustainable Development, National Observatory of Athens, 11810, Athens, Greece
| | | | - Shiv Dev Attri
- India Meteorological Department, New Delhi, 110001, India
| | - Abhay Kumar Singh
- Atmospheric Research Laboratory, Department of Physics, Banaras Hindu University, Varanasi, 221005, India.
- DST-Mahamana Centre of Excellence in Climate Change Research, B.H.U, Varanasi, 221005, India.
| |
Collapse
|
22
|
Priyadharshini B, Verma S, Giles DM, Holben BN. Discerning the pre-monsoon urban atmosphere aerosol characteristic and its potential source type remotely sensed by AERONET over the Bengal Gangetic plain. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:22163-22179. [PMID: 29804246 DOI: 10.1007/s11356-018-2290-x] [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: 09/19/2017] [Accepted: 05/09/2018] [Indexed: 06/08/2023]
Abstract
In the present study, we evaluated the pre-monsoon urban atmosphere (UA) aerosol characteristics remotely sensed by Aerosol Robotic Network (AERONET) over the Bengal Gangetic plain (BGP) at Kolkata (KOL) and their implication in potential source types and spatiotemporal features. About 70% of the AERONET-sensed aerosol optical depth at 0.50 μ m, AOD0.5 (Angstrom exponent, α at 0.44-0.87 μ m) during the pre-monsoon period (February to June) was greater than 0.50 (≤ 1); the pre-monsoon mean of AOD0.5 (α) was 0.73 (0.83) which was found being slightly higher (lower) than nearby AERONET stations (Dhaka/Bhola) located over the eastern Ganges basin. The volume geometric mean radius for the fine mode (FM) (coarse mode, CM) UA aerosol from AERONET retrievals was estimated to be 0.14-0.17 (2.24-2.75) μ m. The spectral distribution of the monthly mean of UA aerosol single-scattering albedo (SSA) exhibited an increasing trend with an increase in wavelength throughout all wavelengths during April, unlike the rest of the pre-monsoon months. Investigation of aerosol types indicated the pre-dominance of dust during April and a mixture of urban/open burning with mixed desert dust during the rest of the pre-monsoon months. Potential aerosol source fields were identified over the Indo-Gangetic Plain (IGP), east coast, northwestern India, and oceanic regions; these were estimated at elevated layers of atmosphere during April and May but that at surface layers during February and June. Comparison of aerosol characteristics over the BGP (at Kolkata, KOL) with that at six other coincident AERONET sites over India revealed mean AOD at KOL being 11 to 91% higher than the rest of the AERONET stations, with the relative increase at KOL being the highest during March; this was attributed to persistent high values of both FM and CM AOD unlike the rest of the stations. The monthly mean of SSA was the lowest at KOL among AERONET stations, during February and March. Comparison of the AOD from the AERONET aerosol retrievals over the BGP UA with the coincident Moderate Resolution Imaging Spectroradiometer (MODIS) latest retrievals (C005 and C006) indicated a moderate correlation between the two retrievals; discrepancy in MODIS-retrieved relative distribution of FM and CM AOD was inferred compared to AERONET in the UA.
Collapse
Affiliation(s)
- Babu Priyadharshini
- Department of Civil Engineering Indian Institute of Technology Kharagpur, Kharagpur, 721302, India
| | - Shubha Verma
- Department of Civil Engineering Indian Institute of Technology Kharagpur, Kharagpur, 721302, India.
| | - David M Giles
- NASA Goddard Space Flight Center, Greenbelt, MD, USA
| | | |
Collapse
|
23
|
Aerosol and Meteorological Parameters Associated with the Intense Dust Event of 15 April 2015 over Beijing, China. REMOTE SENSING 2018. [DOI: 10.3390/rs10060957] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
24
|
Patel PN, Dumka UC, Babu KN, Mathur AK. Aerosol characterization and radiative properties over Kavaratti, a remote island in southern Arabian Sea from the period of observations. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 599-600:165-180. [PMID: 28475910 DOI: 10.1016/j.scitotenv.2017.04.168] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/19/2016] [Revised: 04/18/2017] [Accepted: 04/22/2017] [Indexed: 06/07/2023]
Abstract
Long-term measurements of spectral aerosol optical depth (AOD) using sun/sky radiometer for a period of five years (2009-2014) from the remote island location at Kavaratti (KVT; 10.56°N, 72.64°E) in the southern Arabian sea have been analysed. Climatologically, AODs decrease from October to reach maximum of ~0.6 (at 500nm) in March, followed by a sudden fall towards May. Significant modulations of intra-seasonal timescales over this general pattern are noticed due to the changes in the relative strength of distinctively different sources. The corresponding changes in aerosol inversion parameters reveal the presence of coarse-mode aerosols during spring and fine-mode absorbing aerosols in autumn and winter months. An overall dominance of a mixed type of aerosols (~41%) with maximum in winter (~53%) was found via the AOD500 vs. Ångström exponent (α440-870) relationship, while biomass-burning aerosols or thick urban/industrial plumes contribute to ~19%. Spectral dependence of Ångström exponent and aerosol absorbing properties were used to identify the aerosol types and its modification processes. Based on air mass back trajectory analysis, we revealed that the advection of aerosols from Indian subcontinent and western regions plays a major role in modifying the optical properties of aerosols over the observational site. The shortwave aerosol direct radiative forcing estimated via SBDART model ranges from -11.00Wm-2 to -7.38Wm-2, -21.51Wm-2 to -14.33Wm-2 and 3.17Wm-2 and 10.0Wm-2 at top of atmosphere, surface and within the atmosphere, respectively. This atmospheric forcing translates into heating rate of 0.62-1.04Kday-1. Furthermore, the vertical profiles of aerosols and heating rate exhibit significant increase in lower (during winter and autumn) and mid troposphere (during spring). This may cause serious climate implications over Kavaratti with further consequences on cloud microphysics and monsoon rainfall.
Collapse
Affiliation(s)
- Piyushkumar N Patel
- Calibration & Validation Division, Space Applications Centre, ISRO, Ahmedabad 380 015, India.
| | - U C Dumka
- Aryabhatta Research Institute of Observational Sciences, Nainital 263 001, India.
| | - K N Babu
- Calibration & Validation Division, Space Applications Centre, ISRO, Ahmedabad 380 015, India
| | - A K Mathur
- Calibration & Validation Division, Space Applications Centre, ISRO, Ahmedabad 380 015, India
| |
Collapse
|
25
|
Pandey SK, Vinoj V, Landu K, Babu SS. Declining pre-monsoon dust loading over South Asia: Signature of a changing regional climate. Sci Rep 2017; 7:16062. [PMID: 29167534 PMCID: PMC5700173 DOI: 10.1038/s41598-017-16338-w] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2017] [Accepted: 11/08/2017] [Indexed: 11/04/2022] Open
Abstract
Desert dust over the Indian region during pre-monsoon season is known to strengthen monsoon circulation, by modulating rainfall through the elevated heat pump (EHP) mechanism. In this context, an insight into long term trends of dust loading over this region is of significant importance in understanding monsoon variability. In this study, using long term (2000 to 2015) aerosol measurements from multiple satellites, ground stations and model based reanalysis, we show that dust loading in the atmosphere has decreased by 10 to 20% during the pre-monsoon season with respect to start of this century. Our analysis reveals that this decrease is a result of increasing pre-monsoon rainfall that in turn increases (decreases) wet scavenging (dust emissions) and slowing circulation pattern over the Northwestern part of the sub-continent.
Collapse
Affiliation(s)
- Satyendra K Pandey
- School of Earth, Ocean and Climate Sciences, Indian Institute of Technology Bhubaneswar, Odisha, 752 050, India
| | - V Vinoj
- School of Earth, Ocean and Climate Sciences, Indian Institute of Technology Bhubaneswar, Odisha, 752 050, India.
| | - K Landu
- School of Earth, Ocean and Climate Sciences, Indian Institute of Technology Bhubaneswar, Odisha, 752 050, India
| | - S Suresh Babu
- Space Physics Laboratory, Vikram Sarabhai Space Centre, Trivandrum, Kerala, 695022, India
| |
Collapse
|
26
|
Aerosol Optical Properties and Direct Radiative Effects over Central China. REMOTE SENSING 2017. [DOI: 10.3390/rs9100997] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
27
|
Adesina AJ, Piketh S, Kanike RK, Venkataraman S. Characteristics of columnar aerosol optical and microphysical properties retrieved from the sun photometer and its impact on radiative forcing over Skukuza (South Africa) during 1999-2010. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:16160-16171. [PMID: 28537035 DOI: 10.1007/s11356-017-9211-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Accepted: 05/07/2017] [Indexed: 06/07/2023]
Abstract
The detailed analysis of columnar optical and microphysical properties of aerosols obtained from the AErosol RObotic NETwork (AERONET) Cimel sun photometer operated at Skukuza (24.98° S, 31.60° E, 150 m above sea level), South Africa was carried out using the level 2.0 direct sun and inversion products measured during 1999-2010. The observed aerosol optical depth (AOD) was generally low over the region, with high values noted in late winter (August) and mid-spring (September and October) seasons. The major aerosol types found during the study period were made of 3.74, 69.63, 9.34, 8.83, and 8.41% for polluted dust (PD), polluted continental (PC), non-absorbing (NA), slightly absorbing (SA), and moderately absorbing (MA) aerosols, respectively. Much attention was given to the aerosol fine- and coarse-modes deduced from the particle volume concentration, effective radius, and fine-mode volume fraction. The aerosol volume size distribution pattern was found to be bimodal with the fine-mode showing predominance relative to coarse-mode during the winter and spring seasons, owing to the onset of the biomass burning season. The mean values of total, fine-, and coarse-mode volume particle concentrations were 0.07 ± 0.04, 0.03 ± 0.03, and 0.04 ± 0.02 μm3 μm-2, respectively, whereas the mean respective effective radii observed at Skukuza for the abovementioned modes were 0.35 ± 0.17, 0.14 ± 0.02, and 2.08 ± 0.02 μm. The averaged shortwave direct aerosol radiative forcing (ARF) observed within the atmosphere was found to be positive (absorption or heating effect), whereas the negative forcing in the surface and TOA depicted significant cooling effect due to more scattering type particles.
Collapse
Affiliation(s)
- Ayodele Joseph Adesina
- School of Geo- and Spatial Science, Unit for Environmental Sciences and Management, North-West University, Potchefstroom, 2520, South Africa
| | - Stuart Piketh
- School of Geo- and Spatial Science, Unit for Environmental Sciences and Management, North-West University, Potchefstroom, 2520, South Africa
| | - Raghavendra Kumar Kanike
- Key Laboratory of Meteorological Disasters, Ministry of Education (KLME), Collaborative Innovation Centre on Forecast and Evaluation of Meteorological Disasters, Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, School of Atmospheric Physics, Nanjing University of Information Science and Technology, Nanjing, Jiangsu, 210044, China.
| | - Sivakumar Venkataraman
- Discipline of Physics, School of Chemistry and Physics, University of KwaZulu-Natal, Durban, Kwazulu-Natal, 4000, South Africa
| |
Collapse
|
28
|
Mor V, Dhankhar R, Attri SD, Soni VK, Sateesh M, Taneja K. Assessment of aerosols optical properties and radiative forcing over an Urban site in North-Western India. ENVIRONMENTAL TECHNOLOGY 2017; 38:1232-1244. [PMID: 27564392 DOI: 10.1080/09593330.2016.1221473] [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: 04/04/2016] [Accepted: 08/02/2016] [Indexed: 06/06/2023]
Abstract
The present work is aimed to analyze aerosols optical properties and to estimate aerosol radiative forcing (ARF) from January to December 2013, using sky radiometer data over Rohtak, an urban site in North-Western India. The results reveal strong wavelength dependency of aerosol optical depth (AOD), with high values of AOD at shorter wavelengths and lower values at longer wavelength during the study period. The highest AOD values of 1.07 ± 0.45 at 500 nm were observed during July. A significant decline in Ångström exponent was observed during April-May, which represents the dominance of coarse mode particles due to dust-raising convective activities. Aerosols' size distribution exhibits a bimodal structure with fine mode particles around 0.17 µm and coarse mode particles with a radius around 5.28 µm. Single scattering albedo values were lowest during November-December at all wavelengths, ranging from 0.87 to 0.76, which corresponds to the higher absorption during this period. Aerosols optical properties retrieved during observation period are used as input for SBDART (Santa Barbara DISORT Atmospheric Radiative Transfer) to estimate the direct ARF at the surface, in the atmosphere and at the top of the atmosphere (TOA). The ARF at the TOA, surface and in the atmosphere are found to be in the range of -4.98 to -19.35 W m-2, -8.01 to -57.66 W m-2 and +3.02 to +41.64 W m-2, respectively. The averaged forcing for the whole period of observations at the TOA is -11.26 W m-2, while at the surface it is -38.64 W m-2, leading to atmospheric forcing of 27.38 W m-2. The highest (1.168 K day-1) values of heating rate was estimated during November, whereas the lowest value (0.084 K day-1) was estimated for the February.
Collapse
Affiliation(s)
- Vikram Mor
- a Department of Environment Science , Maharshi Dayanand University , Rohtak , India
| | - Rajesh Dhankhar
- a Department of Environment Science , Maharshi Dayanand University , Rohtak , India
| | - S D Attri
- b India Meteorological Department , Ministry of Earth Sciences , New Delhi , India
| | - V K Soni
- b India Meteorological Department , Ministry of Earth Sciences , New Delhi , India
| | - M Sateesh
- b India Meteorological Department , Ministry of Earth Sciences , New Delhi , India
| | - Kanika Taneja
- b India Meteorological Department , Ministry of Earth Sciences , New Delhi , India
| |
Collapse
|
29
|
Patel PN, Dumka UC, Kaskaoutis DG, Babu KN, Mathur AK. Optical and radiative properties of aerosols over Desalpar, a remote site in western India: Source identification, modification processes and aerosol type discrimination. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 575:612-627. [PMID: 27616711 DOI: 10.1016/j.scitotenv.2016.09.023] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/05/2016] [Revised: 09/01/2016] [Accepted: 09/04/2016] [Indexed: 06/06/2023]
Abstract
Aerosol optical properties are analyzed for the first time over Desalpar (23.74°N, 70.69°E, 30m above mean sea level) a remote site in western India during October 2014 to August 2015. Spectral aerosol optical depth (AOD) measurements were performed using the CIMEL CE-318 automatic Sun/sky radiometer. The annual-averaged AOD500 and Ångström exponent (α440-870) values are found to be 0.43±0.26 and 0.69±0.39, respectively. On the seasonal basis, high AOD500 of 0.45±0.30 and 0.61±0.34 along with low α440-870 of 0.41±0.27 and 0.41±0.35 during spring (March-May) and summer (June-August), respectively, suggest the dominance of coarse-mode aerosols, while significant contribution from anthropogenic sources is observed in autumn (AOD500=0.47±0.26, α440-870=1.02±0.27). The volume size distribution and the spectral single-scattering albedo also confirm the presence of coarse-mode aerosols during March-August. An overall dominance of a mixed type of aerosols (~56%) mostly from October to February is found via the AOD500 vs α440-870 relationship, while marine aerosols contribute to ~18%. Spectral dependence of α and its second derivative (α') are also used for studying the aerosol modification processes. The average direct aerosol radiative forcing (DARF) computed via the SBDART model is estimated to range from -27.08Wm-2 to -10.74Wm-2 at the top of the atmosphere, from -52.21Wm-2 to -21.71Wm-2 at the surface and from 10.97Wm-2 to 26.54Wm-2 within the atmosphere. This atmospheric forcing translates into heating rates of 0.31-0.75Kday-1. The aerosol properties and DARF are also examined for different trajectory clusters in order to identify the sources and to assess the influence of long-range transported aerosols over Desalpar.
Collapse
Affiliation(s)
- Piyushkumar N Patel
- Calibration & Validation Division, Space Applications Centre, ISRO, Ahmedabad 380 015, India
| | - U C Dumka
- Aryabhatta Research Institute of Observational Sciences, Nainital 263 001, India.
| | - D G Kaskaoutis
- Atmospheric Research Team, Institute for Environmental Research and Sustainable Development, National Observatory of Athens, GR, 11810 Athens, Greece
| | - K N Babu
- Calibration & Validation Division, Space Applications Centre, ISRO, Ahmedabad 380 015, India
| | - Alok K Mathur
- Calibration & Validation Division, Space Applications Centre, ISRO, Ahmedabad 380 015, India
| |
Collapse
|
30
|
Begam GR, Vachaspati CV, Ahammed YN, Kumar KR, Reddy RR, Sharma SK, Saxena M, Mandal TK. Seasonal characteristics of water-soluble inorganic ions and carbonaceous aerosols in total suspended particulate matter at a rural semi-arid site, Kadapa (India). ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2017; 24:1719-1734. [PMID: 27796981 DOI: 10.1007/s11356-016-7917-1] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2016] [Accepted: 10/16/2016] [Indexed: 05/10/2023]
Abstract
To better understand the sources as well as characterization of regional aerosols at a rural semi-arid region Kadapa (India), size-resolved composition of atmospheric particulate matter (PM) mass concentrations was sampled and analysed. This was carried out by using the Anderson low-pressure impactor for a period of 2 years during March 2013-February 2015. Also, the variations of organic carbon (OC), elemental carbon (EC) and water-soluble inorganic ion components (WSICs) present in total suspended particulate matter (TSPM) were studied over the measurement site. From the statistical analysis, the PM mass concentration showed a higher abundance of coarse mode particles than the fine mode during pre-monsoon season. In contrast, fine mode particles in the PM concentration showed dominance over coarse mode particle contribution during the winter. During the post-monsoon season, the percentage contributions of coarse and fine fractions were equal, whereas during the monsoon, coarse mode fraction was approximately 26 % higher than the fine mode. This distinct feature in the case of fine mode particles during the studied period is mainly attributed to large-scale anthropogenic activities and regional prevailing meteorological conditions. Further, the potential sources of PM have been identified qualitatively by using the ratios of certain ions. A high sulphate (SO4) concentration at the measurement site was observed during the studied period which is caused by the nearby/surrounding mining activity. Carbon fractions (OC and EC) were also analysed from the TSPM, and the results indicated (OC/EC ratio of ~4.2) the formation of a secondary organic aerosol. At last, the cluster backward trajectory analyses were also performed at Kadapa for different seasons to reveal the origin of sources from long-range transport during the study period.
Collapse
Affiliation(s)
- G Reshma Begam
- Atmospheric Science Laboratory, Department of Physics, Yogi Vemana University, Kadapa, Andhra Pradesh, 516 003, India
| | - C Viswanatha Vachaspati
- Atmospheric Science Laboratory, Department of Physics, Yogi Vemana University, Kadapa, Andhra Pradesh, 516 003, India
| | - Y Nazeer Ahammed
- Atmospheric Science Laboratory, Department of Physics, Yogi Vemana University, Kadapa, Andhra Pradesh, 516 003, India.
| | - K Raghavendra Kumar
- Collaborative Innovation Centre for Forecast and Evaluation of Meteorological Disasters, Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, School of Atmospheric Physics, Nanjing University of Information Science and Technology, Nanjing, Jiangsu, 210044, China
| | - R R Reddy
- Aerosol and Atmospheric Research Laboratory, Department of Physics, Sri Krishnadevaraya University, Anantapur, Andhra Pradesh, 515 003, India
| | - S K Sharma
- CSIR-National Physical Laboratory, DR. K S Krishna Road, New Delhi, 110 012, India
| | - Mohit Saxena
- CSIR-National Physical Laboratory, DR. K S Krishna Road, New Delhi, 110 012, India
| | - T K Mandal
- CSIR-National Physical Laboratory, DR. K S Krishna Road, New Delhi, 110 012, India
| |
Collapse
|
31
|
Kang N, Kumar KR, Yu X, Yin Y. Column-integrated aerosol optical properties and direct radiative forcing over the urban-industrial megacity Nanjing in the Yangtze River Delta, China. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2016; 23:17532-17552. [PMID: 27234827 DOI: 10.1007/s11356-016-6953-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2016] [Accepted: 05/20/2016] [Indexed: 06/05/2023]
Abstract
Aerosol optical properties were measured and analyzed through the ground-based remote sensing Aerosol Robotic Network (AERONET) over an urban-industrial site, Nanjing (32.21° N, 118.72° E, and 62 m above sea level), in the Yangtze River Delta, China, during September 2007-August 2008. The annual averaged values of aerosol optical depth (AOD500) and the Ångström exponent (AE440-870) were measured to be 0.94 ± 0.52 and 1.10 ± 0.21, respectively. The seasonal averaged values of AOD500 (AE440-870) were noticed to be high in summer (autumn) and low in autumn (spring). The characterization of aerosol types showed the dominance of mixed type followed by the biomass burning and urban-industrial type of aerosol at Nanjing. Subsequently, the curvature (a 2) obtained from the second-order polynomial fit and the second derivative of AE (α') were also analyzed to understand the dominant aerosol type. The single scattering albedo at 440 nm (SSA440) varied from 0.88 to 0.93 with relatively lower (higher) values during the summer (spring), suggesting an increase in black carbon and mineral dust (desert dust) aerosols of absorbing (scattering) nature. The averaged monthly and seasonal evolutions of shortwave (0.3-4.0 μm) direct aerosol radiative forcing (DARF) values were computed from the Santa Barbara DISORT Atmospheric Radiative Transfer (SBDART) model both at the top of atmosphere (TOA) and bottom of atmosphere (SUR) during the study period. Further, the aerosol forcing efficiency (AFE) and the corresponding atmospheric heating rates (AHR) were also estimated from the forcing within the atmosphere (ATM). The derived DARF values, therefore, produced a warming effect within the atmosphere due to strong absorption of solar radiation.
Collapse
Affiliation(s)
- Na Kang
- Key Laboratory of Meteorological Disaster, Ministry of Education (KLME)/International Joint Laboratory on Climate and Environmental Change (ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, School of Atmospheric Physics, Nanjing University of Information Science and Technology, Nanjing, 210044, Jiangsu, China
| | - K Raghavendra Kumar
- Key Laboratory of Meteorological Disaster, Ministry of Education (KLME)/International Joint Laboratory on Climate and Environmental Change (ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, School of Atmospheric Physics, Nanjing University of Information Science and Technology, Nanjing, 210044, Jiangsu, China.
| | - Xingna Yu
- Key Laboratory of Meteorological Disaster, Ministry of Education (KLME)/International Joint Laboratory on Climate and Environmental Change (ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, School of Atmospheric Physics, Nanjing University of Information Science and Technology, Nanjing, 210044, Jiangsu, China
| | - Yan Yin
- Key Laboratory of Meteorological Disaster, Ministry of Education (KLME)/International Joint Laboratory on Climate and Environmental Change (ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters/Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, School of Atmospheric Physics, Nanjing University of Information Science and Technology, Nanjing, 210044, Jiangsu, China
| |
Collapse
|
32
|
Yu X, Lü R, Kumar KR, Ma J, Zhang Q, Jiang Y, Kang N, Yang S, Wang J, Li M. Dust aerosol properties and radiative forcing observed in spring during 2001-2014 over urban Beijing, China. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2016; 23:15432-15442. [PMID: 27117151 DOI: 10.1007/s11356-016-6727-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Accepted: 04/19/2016] [Indexed: 06/05/2023]
Abstract
The ground-based characteristics (optical and radiative properties) of dust aerosols measured during the springtime between 2001 and 2014 were investigated over urban Beijing, China. The seasonal averaged aerosol optical depth (AOD) during spring of 2001-2014 was about 0.78 at 440 nm. During dust days, higher AOD occurred associated with lower Ångström exponent (AE). The mean AE440-870 in the springtime was about 1.0, indicating dominance of fine particles over the region. The back-trajectory analysis revealed that the dust was transported from the deserts of Inner Mongolia and Mongolia arid regions to Beijing. The aerosol volume size distribution showed a bimodal distribution pattern, with its highest peak observed in coarse mode for all episodes (especially for dust days with increased volume concentration). The single scattering albedo (SSA) increased with wavelength on dust days, indicating the presence of more scattering particles. Furthermore, the complex parts (real and imaginary) of refractive index showed distinct characteristics with lower imaginary values (also scattering) on dust days. The shortwave (SW; 0.2-4.0 μm) and longwave (LW; 4-100 μm) aerosol radiative forcing (ARF) values were computed from the Santa Barbara DISORT Atmospheric Radiative Transfer (SBDART) model both at the top of atmosphere (TOA) and the bottom of atmosphere (BOA) during dust and non-dust (dust free) days, and the corresponding heating rates and forcing efficiencies were also estimated. The SW (LW) ARF, therefore, produced significant cooling (warming) effects at both the TOA and the BOA over Beijing.
Collapse
Affiliation(s)
- Xingna Yu
- Key Laboratory of Meteorological Disaster, Ministry of Education (KLME)/Joint International Research Laboratory of Climate and Environment Change (ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD)/Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, Nanjing University of Information Science and Technology, Nanjing, 210044, China
| | - Rui Lü
- Key Laboratory of Meteorological Disaster, Ministry of Education (KLME)/Joint International Research Laboratory of Climate and Environment Change (ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD)/Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, Nanjing University of Information Science and Technology, Nanjing, 210044, China
| | - K Raghavendra Kumar
- Key Laboratory of Meteorological Disaster, Ministry of Education (KLME)/Joint International Research Laboratory of Climate and Environment Change (ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD)/Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, Nanjing University of Information Science and Technology, Nanjing, 210044, China.
| | - Jia Ma
- Key Laboratory of Meteorological Disaster, Ministry of Education (KLME)/Joint International Research Laboratory of Climate and Environment Change (ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD)/Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, Nanjing University of Information Science and Technology, Nanjing, 210044, China
- Guangzhou Hexin Analytical Instrument Company Limited, Guangzhou, 510530, China
| | - Qiuju Zhang
- Baoshan District Center for Disease Control and Prevention, Shanghai, 201901, China
| | - Yilun Jiang
- Guangzhou Hexin Analytical Instrument Company Limited, Guangzhou, 510530, China
| | - Na Kang
- Key Laboratory of Meteorological Disaster, Ministry of Education (KLME)/Joint International Research Laboratory of Climate and Environment Change (ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD)/Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, Nanjing University of Information Science and Technology, Nanjing, 210044, China
| | - Suying Yang
- Key Laboratory of Meteorological Disaster, Ministry of Education (KLME)/Joint International Research Laboratory of Climate and Environment Change (ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD)/Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, Nanjing University of Information Science and Technology, Nanjing, 210044, China
| | - Jing Wang
- Key Laboratory of Meteorological Disaster, Ministry of Education (KLME)/Joint International Research Laboratory of Climate and Environment Change (ILCEC)/Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD)/Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, Nanjing University of Information Science and Technology, Nanjing, 210044, China
| | - Mei Li
- Institute of Atmospheric Environment Safety and Pollution Control, Jinan University, Guangzhou, 510632, China.
| |
Collapse
|
33
|
Soni K, Parmar KS, Kapoor S, Kumar N. Statistical variability comparison in MODIS and AERONET derived aerosol optical depth over Indo-Gangetic Plains using time series modeling. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 553:258-265. [PMID: 26925737 DOI: 10.1016/j.scitotenv.2016.02.075] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2015] [Revised: 02/10/2016] [Accepted: 02/11/2016] [Indexed: 05/11/2023]
Abstract
A lot of studies in the literature of Aerosol Optical Depth (AOD) done by using Moderate Resolution Imaging Spectroradiometer (MODIS) derived data, but the accuracy of satellite data in comparison to ground data derived from ARrosol Robotic NETwork (AERONET) has been always questionable. So to overcome from this situation, comparative study of a comprehensive ground based and satellite data for the period of 2001-2012 is modeled. The time series model is used for the accurate prediction of AOD and statistical variability is compared to assess the performance of the model in both cases. Root mean square error (RMSE), mean absolute percentage error (MAPE), stationary R-squared, R-squared, maximum absolute percentage error (MAPE), normalized Bayesian information criterion (NBIC) and Ljung-Box methods are used to check the applicability and validity of the developed ARIMA models revealing significant precision in the model performance. It was found that, it is possible to predict the AOD by statistical modeling using time series obtained from past data of MODIS and AERONET as input data. Moreover, the result shows that MODIS data can be formed from AERONET data by adding 0.251627 ± 0.133589 and vice-versa by subtracting. From the forecast available for AODs for the next four years (2013-2017) by using the developed ARIMA model, it is concluded that the forecasted ground AOD has increased trend.
Collapse
Affiliation(s)
- Kirti Soni
- CSIR-National Physical Laboratory, Delhi, India
| | - Kulwinder Singh Parmar
- Department of Mathematics, Dr. B.R. Ambedkar National Institute of Technology, Jalandhar, Punjab 144011, India.
| | - Sangeeta Kapoor
- Laxmi Narayan College of Technology & Science (LNCTS), Bhopal, MP, India
| | | |
Collapse
|
34
|
Yu X, Kumar KR, Lü R, Ma J. Changes in column aerosol optical properties during extreme haze-fog episodes in January 2013 over urban Beijing. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2016; 210:217-226. [PMID: 26735167 DOI: 10.1016/j.envpol.2015.12.021] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2015] [Revised: 12/09/2015] [Accepted: 12/10/2015] [Indexed: 06/05/2023]
Abstract
Several dense haze-fog (HF) episodes were occurred in the North China Plain (NCP), especially over Beijing in January 2013 characterized by a long duration, a large influential region, and an extremely high PM2.5 values (>500 μg m(-3)). In this study, we present the characteristics of aerosol optical properties and radiative forcing using Cimel sun-sky radiometer measurements during HF and no haze-fog (NHF) episodes occurred over Beijing during 1-31 January, 2013. The respective maximum values of daily mean aerosol optical depth at 440 nm (AOD440) were observed to be 1.21, 1.43, 1.52, and 2.21 occurred on 12, 14 19, and 28 January. It was found that the Ångström exponent (AE) values were almost higher than 1.0 during all the days with its maximum on 26 January (1.53), suggests the dominance of fine-mode particles. The maximum (minimum) aerosol volume size distributions occurred during dense HF (NHF) days with larger particle volumes of fine-mode. The single scattering albedo, asymmetry parameter, and complex refractive index values during HF events suggest the abundance of fine-mode particles from anthropogenic (absorbing) activities mixed with scattering dust particles. The average shortwave direct aerosol radiative forcing (DARF) values at the bottom-of-atmosphere (BOA) during HF and NHF days were estimated to be 112.29 ± 42.18 W m(-2) and -58.61 ± 13.09 W m(-2), while at the top-of-atmosphere (TOA) the forcing values were -45.78 ± 22.17 W m(-2) and -18.64 ± 5.84 W m(-2), with the corresponding heating rate of 1.61 ± 0.48 K day(-1) and 1.12 ± 0.31 K day(-1), respectively. The DARF values retrieved from the AERONET were in good agreement with the SBDART computed both at the TOA (r = 0.95) and the BOA (r = 0.97) over Beijing in January 2013.
Collapse
Affiliation(s)
- Xingna Yu
- Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, School of Atmospheric Physics, Nanjing University of Information Science and Technology, Nanjing 210044, Jiangsu province, China
| | - K Raghavendra Kumar
- Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, School of Atmospheric Physics, Nanjing University of Information Science and Technology, Nanjing 210044, Jiangsu province, China.
| | - Rui Lü
- Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, School of Atmospheric Physics, Nanjing University of Information Science and Technology, Nanjing 210044, Jiangsu province, China
| | - Jia Ma
- Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, School of Atmospheric Physics, Nanjing University of Information Science and Technology, Nanjing 210044, Jiangsu province, China
| |
Collapse
|
35
|
Shamjad PM, Tripathi SN, Pathak R, Hallquist M, Arola A, Bergin MH. Contribution of Brown Carbon to Direct Radiative Forcing over the Indo-Gangetic Plain. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:10474-81. [PMID: 26237141 DOI: 10.1021/acs.est.5b03368] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
The Indo-Gangetic Plain is a region of known high aerosol loading with substantial amounts of carbonaceous aerosols from a variety of sources, often dominated by biomass burning. Although black carbon has been shown to play an important role in the absorption of solar energy and hence direct radiative forcing (DRF), little is known regarding the influence of light absorbing brown carbon (BrC) on the radiative balance in the region. With this in mind, a study was conducted for a one month period during the winter-spring season of 2013 in Kanpur, India that measured aerosol chemical and physical properties that were used to estimate the sources of carbonaceous aerosols, as well as parameters necessary to estimate direct forcing by aerosols and the contribution of BrC absorption to the atmospheric energy balance. Positive matrix factorization analyses, based on aerosol mass spectrometer measurements, resolved organic carbon into four factors including low-volatile oxygenated organic aerosols, semivolatile oxygenated organic aerosols, biomass burning, and hydrocarbon like organic aerosols. Three-wavelength absorption and scattering coefficient measurements from a Photo Acoustic Soot Spectrometer were used to estimate aerosol optical properties and estimate the relative contribution of BrC to atmospheric absorption. Mean ± standard deviation values of short-wave cloud free clear sky DRF exerted by total aerosols at the top of atmosphere, surface and within the atmospheric column are -6.1 ± 3.2, -31.6 ± 11, and 25.5 ± 10.2 W/m(2), respectively. During days dominated by biomass burning the absorption of solar energy by aerosols within the atmosphere increased by ∼35%, accompanied by a 25% increase in negative surface DRF. DRF at the top of atmosphere during biomass burning days decreased in negative magnitude by several W/m(2) due to enhanced atmospheric absorption by biomass aerosols, including BrC. The contribution of BrC to atmospheric absorption is estimated to range from on average 2.6 W/m(2) for typical ambient conditions to 3.6 W/m(2) during biomass burning days. This suggests that BrC accounts for 10-15% of the total aerosol absorption in the atmosphere, indicating that BrC likely plays an important role in surface and boundary temperature as well as climate.
Collapse
Affiliation(s)
- P M Shamjad
- Department of Civil Engineering, and Centre for Environmental Science and Engineering, Indian Institute of Technology Kanpur , Kanpur, India
| | - S N Tripathi
- Department of Civil Engineering, and Centre for Environmental Science and Engineering, Indian Institute of Technology Kanpur , Kanpur, India
| | - Ravi Pathak
- Atmospheric Science, Department of Chemistry and Molecular Biology, University of Gothenburg , SE-41296 Gothenburg, Sweden
| | - M Hallquist
- Atmospheric Science, Department of Chemistry and Molecular Biology, University of Gothenburg , SE-41296 Gothenburg, Sweden
| | - Antti Arola
- Finnish Meteorological Institute , P.O. Box 1627, 70211 Kuopio, Finland
| | - M H Bergin
- School of Earth and Atmospheric Sciences, Georgia Institute of Technology , Atlanta, Georgia, United States
| |
Collapse
|
36
|
Srivastava AK, Ram K, Singh S, Kumar S, Tiwari S. Aerosol optical properties and radiative effects over Manora Peak in the Himalayan foothills: seasonal variability and role of transported aerosols. THE SCIENCE OF THE TOTAL ENVIRONMENT 2015; 502:287-295. [PMID: 25261819 DOI: 10.1016/j.scitotenv.2014.09.015] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2014] [Revised: 07/03/2014] [Accepted: 09/07/2014] [Indexed: 06/03/2023]
Abstract
The higher altitude regions of Himalayas and Tibetan Plateau are influenced by the dust and black carbon (BC) aerosols from the emissions and long-range transport from the adjoining areas. In this study, we present impacts of advection of polluted air masses of natural and anthropogenic emissions, on aerosol optical and radiative properties at Manora Peak (~2000 m amsl) in central Himalaya over a period of more than two years (February 2006-May 2008). We used the most updated and comprehensive data of chemical and optical properties available in one of the most climatically sensitive region, the Himalaya, to estimate atmospheric radiative forcing and heating rate. Aerosol optical depth (AOD) was found to vary from 0.04 to 0.45 with significantly higher values in summer mainly due to an increase in mineral dust and biomass burning aerosols due to transport. In contrast, single scattering albedo (SSA) varied from 0.74 to 0.88 with relatively lower values during summer, suggesting an increase in absorbing BC and mineral dust aerosols. As a result, a large positive atmospheric radiative forcing (about 28 ± 5 Wm(-2)) and high values of corresponding heating rate (0.80 ± 0.14 Kday(-1)) has been found during summer. During the entire observation period, radiative forcing at the top of the atmosphere varied from -2 to +14 Wm(-2) and from -3 to -50 Wm(-2) at the surface whereas atmospheric forcing was in the range of 3 to 65 Wm(-2) resulting in a heating rate of 0.1-1.8 Kday(-1).
Collapse
Affiliation(s)
- A K Srivastava
- Indian Institute of Tropical Meteorology (Branch), Prof Ramnath Vij Marg, New Delhi, India
| | - K Ram
- Institute of Environment & Sustainable Development, Banaras Hindu University, Varanasi, India
| | - Sachchidanand Singh
- Radio & Atmospheric Sciences Division, CSIR-National Physical Laboratory, New Delhi, India.
| | - Sanjeev Kumar
- Radio & Atmospheric Sciences Division, CSIR-National Physical Laboratory, New Delhi, India
| | - S Tiwari
- Indian Institute of Tropical Meteorology (Branch), Prof Ramnath Vij Marg, New Delhi, India
| |
Collapse
|
37
|
Hersey SP, Garland RM, Crosbie E, Shingler T, Sorooshian A, Piketh S, Burger R. An overview of regional and local characteristics of aerosols in South Africa using satellite, ground, and modeling data. ATMOSPHERIC CHEMISTRY AND PHYSICS 2015; 15:4259-4278. [PMID: 26312061 PMCID: PMC4547400 DOI: 10.5194/acp-15-4259-2015] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
We present a comprehensive overview of particulate air quality across the five major metropolitan areas of South Africa (Cape Town, Bloemfontein, Johannesburg and Tshwane (Gauteng Province), the Industrial Highveld Air Quality Priority Area (HVAPA), and Durban), based on a decadal (1 January 2000 to 31 December 2009) aerosol climatology from multiple satellite platforms and detailed analysis of ground-based data from 19 sites throughout Gauteng Province. Satellite analysis was based on aerosol optical depth (AOD) from MODIS Aqua and Terra (550 nm) and MISR (555 nm) platforms, Ångström Exponent (α) from MODIS Aqua (550/865 nm) and Terra (470/660 nm), ultraviolet aerosol index (UVAI) from TOMS, and results from the Goddard Ozone Chemistry Aerosol Radiation and Transport (GOCART) model. At continentally influenced sites, AOD, α, and UVAI reach maxima (0.12-0.20, 1.0-1.8, and 1.0-1.2, respectively) during austral spring (September-October), coinciding with a period of enhanced dust generation and the maximum integrated intensity of close-proximity and subtropical fires identified by MODIS Fire Information for Resource Management System (FIRMS). Minima in AOD, α, and UVAI occur during winter. Results from ground monitoring indicate that low-income township sites experience by far the worst particulate air quality in South Africa, with seasonally averaged PM10 concentrations as much as 136 % higher in townships that in industrial areas. We report poor agreement between satellite and ground aerosol measurements, with maximum surface aerosol concentrations coinciding with minima in AOD, α, and UVAI. This result suggests that remotely sensed data are not an appropriate surrogate for ground air quality in metropolitan South Africa.
Collapse
Affiliation(s)
- S. P. Hersey
- Department of Environmental Sciences and Management, North-West University, Potchefstroom, South Africa
- Now at Franklin W. Olin College of Engineering, Needham, MA, USA
| | - R. M. Garland
- Now at Franklin W. Olin College of Engineering, Needham, MA, USA
- Council for Scientific and Industrial Research (CSIR), Pretoria, South Africa
| | - E. Crosbie
- Department of Atmospheric Sciences, University of Arizona, Tucson, AZ, USA
| | - T. Shingler
- Department of Atmospheric Sciences, University of Arizona, Tucson, AZ, USA
| | - A. Sorooshian
- Department of Atmospheric Sciences, University of Arizona, Tucson, AZ, USA
- Department of Chemical and Environmental Engineering, University of Arizona, Tucson, AZ, USA
| | - S. Piketh
- Department of Environmental Sciences and Management, North-West University, Potchefstroom, South Africa
| | - R. Burger
- Department of Environmental Sciences and Management, North-West University, Potchefstroom, South Africa
| |
Collapse
|
38
|
Adesina AJ, Kumar KR, Sivakumar V, Griffith D. Direct radiative forcing of urban aerosols over Pretoria (25.75°S, 28.28°E) using AERONET Sunphotometer data: first scientific results and environmental impact. J Environ Sci (China) 2014; 26:2459-2474. [PMID: 25499494 DOI: 10.1016/j.jes.2014.04.006] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2014] [Revised: 03/26/2014] [Accepted: 04/17/2014] [Indexed: 06/04/2023]
Abstract
The present study uses the data collected from Cimel Sunphotometer of Aerosol Robotic Network (AERONET) for the period from January to December, 2012 over an urban site, Pretoria (PTR; 25.75°S, 28.28°E, 1449 m above sea level), South Africa. We found that monthly mean aerosol optical depth (AOD, τ(a)) exhibits two maxima that occurred in summer (February) and winter (August) having values of 0.36 ± 0.19 and 0.25 ± 0.14, respectively, high-to-moderate values in spring and thereafter, decreases from autumn with a minima in early winter (June) 0.12 ± 0.07. The Angstrom exponents (α440-870) likewise, have its peak in summer (January) 1.70 ± 0.21 and lowest in early winter (June) 1.38 ± 0.26, while the columnar water vapor (CWV) followed AOD pattern with high values (summer) at the beginning of the year (February, 2.10 ± 0.37 cm) and low values (winter) in the middle of the year (July, 0.66 ± 0.21 cm). The volume size distribution (VSD) in the fine-mode is higher in the summer and spring seasons, whereas in the coarse mode the VSD is higher in the winter and lower in the summer due to the hygroscopic growth of aerosol particles. The single scattering albedo (SSA) ranged from 0.85 to 0.96 at 440 nm over PTR for the entire study period. The averaged aerosol radiative forcing (ARF) computed using SBDART model at the top of the atmosphere (TOA) was -8.78 ± 3.1 W/m², while at the surface it was -25.69 ± 8.1 W/m² leading to an atmospheric forcing of +16.91 ± 6.8 W/m², indicating significant heating of the atmosphere with a mean of 0.47K/day.
Collapse
Affiliation(s)
- Ayodele Joseph Adesina
- Discipline of Physics, School of Chemistry and Physics, College of Agriculture, Engineering and Science, Westville Campus, University of KwaZulu-Natal, Durban 4000, South Africa.
| | - Kanike Raghavendra Kumar
- Discipline of Physics, School of Chemistry and Physics, College of Agriculture, Engineering and Science, Westville Campus, University of KwaZulu-Natal, Durban 4000, South Africa; Key Laboratory for Aerosol-Cloud-Precipitation of China Meteorological Administration, School of Atmospheric Physics, Nanjing University of Information Science and Technology, Nanjing 210044, China.
| | - Venkataraman Sivakumar
- Discipline of Physics, School of Chemistry and Physics, College of Agriculture, Engineering and Science, Westville Campus, University of KwaZulu-Natal, Durban 4000, South Africa
| | - Derek Griffith
- Optronic Sensor Systems, Council for Scientific and Industrial Research (CSIR)-DPSS, Pretoria 0001, South Africa
| |
Collapse
|
39
|
Crosbie E, Sorooshian A, Monfared NA, Shingler T, Esmaili O. A Multi-Year Aerosol Characterization for the Greater Tehran Area Using Satellite, Surface, and Modeling Data. ATMOSPHERE 2014; 5:178-197. [PMID: 25083295 PMCID: PMC4114406 DOI: 10.3390/atmos5020178] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
This study reports a multi-year (2000–2009) aerosol characterization for metropolitan Tehran and surrounding areas using multiple datasets (Moderate Resolution Imaging Spectroradiometer (MODIS), Multi-angle Imaging Spectroradiometer (MISR), Total Ozone Mapping Spectrometer (TOMS), Goddard Ozone Chemistry Aerosol Radiation and Transport (GOCART), and surface and upper air data from local stations). Monthly trends in aerosol characteristics are examined in the context of the local meteorology, regional and local emission sources, and air mass back-trajectory data. Dust strongly affects the region during the late spring and summer months (May–August) when aerosol optical depth (AOD) is at its peak and precipitation accumulation is at a minimum. In addition, the peak AOD that occurs in July is further enhanced by a substantial number of seasonal wildfires in upwind regions. Conversely, AOD is at a minimum during winter; however, reduced mixing heights and a stagnant lower atmosphere trap local aerosol emissions near the surface and lead to significant reductions in visibility within Tehran. The unique meteorology and topographic setting makes wintertime visibility and surface aerosol concentrations particularly sensitive to local anthropogenic sources and is evident in the noteworthy improvement in visibility observed on weekends. Scavenging of aerosol due to precipitation is evident during the winter when aconsistent increase in surface visibility and concurrent decrease in AOD is observed in the days after rain compared with the days immediately before rain.
Collapse
Affiliation(s)
- Ewan Crosbie
- Department of Atmospheric Sciences, University of Arizona, Tucson, AZ 85721, USA
| | - Armin Sorooshian
- Department of Atmospheric Sciences, University of Arizona, Tucson, AZ 85721, USA
- Department of Chemical and Environmental Engineering, University of Arizona, Tucson, AZ 85721, USA
- Author to whom correspondence should be addressed; ; Tel.: +1-52-0626-5858
| | | | - Taylor Shingler
- Department of Chemical and Environmental Engineering, University of Arizona, Tucson, AZ 85721, USA
| | - Omid Esmaili
- Department of Civil & Environmental Engineering, University of California, Irvine, Irvine, CA 92697, USA
| |
Collapse
|
40
|
Aerosol Optical Properties over South Asia from Ground-Based Observations and Remote Sensing: A Review. CLIMATE 2013. [DOI: 10.3390/cli1030084] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
|
41
|
Verma S, Payra S, Gautam R, Prakash D, Soni M, Holben B, Bell S. Dust events and their influence on aerosol optical properties over Jaipur in Northwestern India. ENVIRONMENTAL MONITORING AND ASSESSMENT 2013; 185:7327-42. [PMID: 23397540 DOI: 10.1007/s10661-013-3103-9] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/04/2012] [Accepted: 01/16/2013] [Indexed: 05/04/2023]
Abstract
In this study, we systematically document the link between dust episodes and local scale regional aerosol optical properties over Jaipur located in the vicinity of Thar Desert in the northwestern state of Rajasthan. The seasonal variation of AOT(500 nm) (aerosol optical thickness) shows high values (0.51 ± 0.18) during pre-monsoon (dust dominant) season while low values (0.36 ± 0.14) are exhibited during winter. The Ångström wavelength exponent has been found to exhibit low value (<0.25) indicating relative dominance of coarse-mode particles during pre-monsoon season. The AOT increased from 0.36 (Aprilmean) to 0.575 (May-June(mean)). Consequently, volume concentration range increases from April through May-June followed by a sharp decline in July during the first active phase of the monsoon. Significantly high dust storms were observed over Jaipur as indicated by high values of single scattering albedo (SSA(440 nm) = 0.89, SSA(675 nm) = 0.95, SSA870 nm = 0.97, SSA(1,020 nm) = 0.976) than the previously reported values over IGP region sites. The larger SSA values (more scattering aerosol), especially at longer wavelengths, is due to the abundant dust loading, and is attributed to the measurement site's proximity to the Thar Desert. The mean and standard deviation in SSA and asymmetry parameter during pre-monsoon season over Jaipur is 0.938 ± 0.023 and 0.712 ± 0.017 at 675 nm wavelength, respectively. Back-trajectory air mass simulations suggest Thar Desert in northwestern India as the primary source of high aerosols dust loading over Jaipur region as well as contribution by long-range transport from the Arabian Peninsula and Middle East gulf regions, during pre-monsoon season.
Collapse
Affiliation(s)
- Sunita Verma
- Centre of Excellence in Climatology, Birla Institute of Technology Mesra, Extension Centre Jaipur, Jaipur, 302017 Rajasthan, India.
| | | | | | | | | | | | | |
Collapse
|
42
|
Gupta T, Mandariya A. Sources of submicron aerosol during fog-dominated wintertime at Kanpur. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2013; 20:5615-5629. [PMID: 23443945 DOI: 10.1007/s11356-013-1580-6] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2012] [Accepted: 02/13/2013] [Indexed: 06/01/2023]
Abstract
The main objective of this atmospheric study was to determine the major sources of PM1 (particles having aerodynamic diameter <1.0 μm) within and near the city of Kanpur, in the Indo-Gangetic Plain. Day and night, 10 h long each, filter-based aerosol samples were collected for 4 months (November 2009 to February 2010) throughout the winter season. These samples were subjected to gravimetric and quantitative chemical analyses for determining water-soluble ions (NH4 (+), F(-), Cl(-), NO3 (-), and SO4 (2-)) using an ion chromatograph and trace elements using an inductively coupled plasma-optical emission spectrometer. The mean PM1 mass concentrations were recorded as 114 ± 71 μg/m(3) (day) and 143 ± 86 μg/m(3) (night), respectively. A significantly higher diurnal contribution of ions (NH4 (+), F(-), Cl(-), NO3 (-), and SO4 (2-)) in PM1 mass was observed during the fog-affected days and nights throughout the winter season, for which the average values were recorded as 38.09 ± 13.39 % (day) and 34.98 ± 12.59 % (night), respectively, of the total PM1 mass. This chemical dataset was then used in a source-receptor model, UNMIX, and the model results are described in detail. UNMIX provided a maximum number of five source factors, including crustal material, composite vehicle, secondary aerosol, coal combustion, and iron/steel production and metallurgical industries, as the dominant air pollution sources for this study.
Collapse
Affiliation(s)
- Tarun Gupta
- Department of Civil Engineering, Indian Institute of Technology Kanpur, Kanpur, 208016, India.
| | | |
Collapse
|
43
|
Kishcha P, Starobinets B, Long CN, Alpert P. Unexpected increasing AOT trends over northwest Bay of Bengal in the early postmonsoon season. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/2012jd018726] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
44
|
Giles DM, Holben BN, Eck TF, Sinyuk A, Smirnov A, Slutsker I, Dickerson RR, Thompson AM, Schafer JS. An analysis of AERONET aerosol absorption properties and classifications representative of aerosol source regions. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/2012jd018127] [Citation(s) in RCA: 249] [Impact Index Per Article: 20.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
45
|
Shamjad PM, Tripathi SN, Aggarwal SG, Mishra SK, Joshi M, Khan A, Sapra BK, Ram K. Comparison of experimental and modeled absorption enhancement by black carbon (BC) cored polydisperse aerosols under hygroscopic conditions. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2012; 46:8082-8089. [PMID: 22788781 DOI: 10.1021/es300295v] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The quantification of the radiative impacts of light absorbing ambient black carbon (BC) particles strongly depends on accurate measurements of BC mass concentration and absorption coefficient (β(abs)). In this study, an experiment has been conducted to quantify the influence of hygroscopic growth of ambient particles on light absorption. Using the hygroscopic growth factor (i.e., Zdanovskii-Stokes-Robinson (ZSR) approach), a model has been developed to predict the chemical composition of particles based on measurements, and the absorption and scattering coefficients are derived using a core-shell assumption with light extinction estimates based on Mie theory. The estimated optical properties agree within 7% for absorption coefficient and 30% for scattering coefficient with that of measured values. The enhancement of absorption is found to vary according to the thickness of the shell and BC mass, with a maximum of 2.3 for a shell thickness of 18 nm for the particles. The findings of this study underline the importance of considering aerosol-mixing states while calculating their radiative forcing.
Collapse
Affiliation(s)
- P M Shamjad
- Department of Civil Engineering, Indian Institute of Technology, Kanpur, India
| | | | | | | | | | | | | | | |
Collapse
|
46
|
Kaskaoutis DG, Gautam R, Singh RP, Houssos EE, Goto D, Singh S, Bartzokas A, Kosmopoulos PG, Sharma M, Hsu NC, Holben BN, Takemura T. Influence of anomalous dry conditions on aerosols over India: Transport, distribution and properties. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/2011jd017314] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
47
|
Eck TF, Holben BN, Reid JS, Giles DM, Rivas MA, Singh RP, Tripathi SN, Bruegge CJ, Platnick S, Arnold GT, Krotkov NA, Carn SA, Sinyuk A, Dubovik O, Arola A, Schafer JS, Artaxo P, Smirnov A, Chen H, Goloub P. Fog- and cloud-induced aerosol modification observed by the Aerosol Robotic Network (AERONET). ACTA ACUST UNITED AC 2012. [DOI: 10.1029/2011jd016839] [Citation(s) in RCA: 72] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
48
|
Ram K, Sarin MM, Tripathi SN. Temporal trends in atmospheric PM₂.₅, PM₁₀, elemental carbon, organic carbon, water-soluble organic carbon, and optical properties: impact of biomass burning emissions in the Indo-Gangetic Plain. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2012; 46:686-695. [PMID: 22192056 DOI: 10.1021/es202857w] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The first simultaneous measurements and analytical data on atmospheric concentrations of PM(2.5), PM(10), inorganic constituents, carbonaceous species, and their optical properties (aerosol optical depth, AOD; absorption coefficient, b(abs); mass absorption efficiency, σ(abs); and single scattering albedo, SSA) from an urban site (Kanpur) in the Indo-Gangetic Plain are reported here. Significantly high aerosol mass concentration (>100 μg m(-3)) and AOD (> 0.3) are seen as a characteristic feature throughout the sampling period, from October 2008 to April 2009. The temporal variability in the mass fractions of carbonaceous species (EC, OC, and WSOC) is pronounced during October-January when emissions from biomass burning are dominant and OC is a major constituent (∼30%) of PM(2.5) mass. The WSOC/OC ratio varies from 0.21 to 0.65, suggesting significant contribution from secondary organic aerosols (SOAs). The mass fraction of SO(4)(2-) in PM(2.5) (Av: 12.5%) exceeds that of NO(3)(-) and NH(4)(+). Aerosol absorption coefficient (@ 678 nm) decreases from 90 Mm(-1) (in December) to 20 Mm(-1) (in April), and a linear regression analysis of the data for b(abs) and EC (n = 54) provides a measure of the mass absorption efficiency of EC (9.6 m(2) g(-1)). In contrast, scattering coefficient (@ 678 nm) increases from 98 Mm(-1) (in January) to 1056 Mm(-1) (in April) and an average mass scattering efficiency of 3.0 ± 0.9 m(2) g(-1) is obtained for PM(10) samples. The highest b(scat) was associated with the dust storm event (April 17, 2009) over northern Iraq, eastern Syria, and southern Turkey; thus, resulting in high SSA (0.93 ± 0.02) during March-April compared to 0.82 ± 0.04 in October-February. These results have implications to large temporal variability in the atmospheric radiative forcing due to aerosols over northern India.
Collapse
Affiliation(s)
- Kirpa Ram
- Physical Research Laboratory, Ahmedabad, India
| | | | | |
Collapse
|
49
|
Giles DM, Holben BN, Tripathi SN, Eck TF, Newcomb WW, Slutsker I, Dickerson RR, Thompson AM, Mattoo S, Wang SH, Singh RP, Sinyuk A, Schafer JS. Aerosol properties over the Indo-Gangetic Plain: A mesoscale perspective from the TIGERZ experiment. ACTA ACUST UNITED AC 2011. [DOI: 10.1029/2011jd015809] [Citation(s) in RCA: 125] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
50
|
Kumar S, Devara PCS, Dani KK, Sonbawne SM, Saha SK. Sun-sky radiometer–derived column-integrated aerosol optical and physical properties over a tropical urban station during 2004–2009. ACTA ACUST UNITED AC 2011. [DOI: 10.1029/2010jd014944] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|