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Yi L, An M, Yu H, Ma Z, Xu L, O'Doherty S, Rigby M, Western LM, Ganesan AL, Zhou L, Shi Q, Hu Y, Yao B, Xu W, Hu J. In Situ Observations of Halogenated Gases at the Shangdianzi Background Station and Emission Estimates for Northern China. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:7217-7229. [PMID: 37126109 DOI: 10.1021/acs.est.3c00695] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
Halogenated gases include ozone-depleting substances and greenhouse gases, such as chlorofluorocarbons, halons, hydrochlorofluorocarbons, hydrofluorocarbons, and perfluorinated gases. In situ atmospheric observations of major halogenated gases were conducted at the Shangdianzi (SDZ) background station, China, from October 2020 to September 2021 using ODS5-pro, a newly developed measurement system. The measurement time series of 36 halogenated gases showed occasional pollution events, where background conditions represented 25% (CH2Cl2) to 81% (CF3Cl, CFC-13) of the measurements. The annual mean background mole fractions of most species at SDZ were consistent with those obtained at the Mace Head station in Ireland. The background conditions were distinguished from pollution events, and the enhanced mole fractions were used to estimate the emissions of four categories of fluorinated gases (F-gases) from northern China using a tracer ratio method. The CO2-equivalent (CO2-equiv) emission of F-gases from northern China reached 181 ± 18 Tg year-1 during 2020-2021. Among the four categories of F-gases estimated, SF6 accounted for the highest proportion of CO2-equiv emissions (24%), followed by HFC-23 (22%), HFC-125 (17%), HFC-134a (13%), NF3 (10%), CF4 (5.9%), HFC-143a (3.9%), HFC-32 (3.4%), and HFC-152a (0.2%).
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Affiliation(s)
- Liying Yi
- State Key Joint Laboratory for Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Minde An
- State Key Joint Laboratory for Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
- School of Chemistry, University of Bristol, Bristol BS8 1TS, U.K
| | - Haibo Yu
- Beijing Huanaco Innovation Co., Ltd., Beijing 102400, China
| | - Zhiqiang Ma
- Institute of Urban Meteorology, China Meteorological Administration, Beijing 100089, China
| | - Lin Xu
- Beijing Huanaco Innovation Co., Ltd., Beijing 102400, China
| | - Simon O'Doherty
- School of Chemistry, University of Bristol, Bristol BS8 1TS, U.K
| | - Matthew Rigby
- School of Chemistry, University of Bristol, Bristol BS8 1TS, U.K
| | - Luke M Western
- School of Chemistry, University of Bristol, Bristol BS8 1TS, U.K
- Global Monitoring Laboratory, National Oceanic and Atmospheric Administration, Boulder, Colorado 80305, United States
| | - Anita L Ganesan
- School of Geographical Sciences, University of Bristol, Bristol BS8 1SS, U.K
| | - Liyan Zhou
- Institute of Urban Meteorology, China Meteorological Administration, Beijing 100089, China
| | - Qingfeng Shi
- Institute of Urban Meteorology, China Meteorological Administration, Beijing 100089, China
| | - Yunxing Hu
- Beijing Huanaco Innovation Co., Ltd., Beijing 102400, China
| | - Bo Yao
- Department of Atmospheric and Oceanic Sciences & Institute of Atmospheric Sciences, Fudan University, Shanghai 200438, China
- Meteorological Observation Centre of China Meteorological Administration (MOC/CMA), Beijing 100081, China
| | - Weiguang Xu
- State Key Joint Laboratory for Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Jianxin Hu
- State Key Joint Laboratory for Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
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Flerlage H, Velders GJM, de Boer J. A review of bottom-up and top-down emission estimates of hydrofluorocarbons (HFCs) in different parts of the world. CHEMOSPHERE 2021; 283:131208. [PMID: 34153914 DOI: 10.1016/j.chemosphere.2021.131208] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2021] [Revised: 06/07/2021] [Accepted: 06/10/2021] [Indexed: 06/13/2023]
Abstract
Hydrofluorocarbons (HFCs) are widespread alternatives for the ozone-depleting substances chlorofluorocarbons and hydrochlorofluorocarbons. They are used mainly as refrigerants or as foam-blowing agents. HFCs do not deplete the ozone layer, but they are very potent greenhouse gases, already contributing to global warming. Since 2019 HFCs are regulated under the Kigali Amendment to the Montreal Protocol, which demands reliable emission estimates to monitor the phase-down. Quantification of emissions is performed with two methods: bottom-up from product inventories or data on chemical sales; or top-down, inferred from atmospheric measurements by inverse modelling or interspecies correlation. Here, we review and compare the two methods and give an overview of HFC emissions from different parts of the world. Emission estimates reported by the different methods vary considerably. HFC emissions of developed countries (Annex I) are reported to the United Nations Framework Convention on Climate Change. These bottom-up estimates add up to only half of global emissions estimated from atmospheric data. Several studies with regional top-down estimates have shown that this gap is not owed to large-scale underreporting of emissions from developed countries, but mostly due to emissions from developing countries (non-Annex I). China accounts for a large fraction of the emissions causing the gap, but not entirely. Bottom-up and top-down estimations of emissions from other developing countries that could identify other large emitters are largely unavailable. Especially South America, West-, Central- and East-Africa, India, the Arabian Peninsula and Northern Australia are not well covered by measurement stations that could provide atmospheric data for top-down estimates.
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Affiliation(s)
- Hannah Flerlage
- Vrije Universiteit, Department of Environment and Health, Faculty of Sciences, De Boelelaan 1085, 1081 HV, Amsterdam, the Netherlands.
| | - Guus J M Velders
- National Institute for Public Health and the Environment (RIVM), Bilthoven, the Netherlands; Institute for Marine and Atmospheric Research Utrecht (IMAU), Utrecht University, the Netherlands
| | - Jacob de Boer
- Vrije Universiteit, Department of Environment and Health, Faculty of Sciences, De Boelelaan 1085, 1081 HV, Amsterdam, the Netherlands
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Yeşiller N, Hanson JL, Sohn AH, Bogner JE, Blake DR. Spatial and Temporal Variability in Emissions of Fluorinated Gases from a California Landfill. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:6789-6797. [PMID: 29792701 DOI: 10.1021/acs.est.8b00845] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Emissions of twelve (hydro)chlorofluorocarbons (F-gases) and methane were quantified using large-scale static chambers as a function of cover type (daily, intermediate, final) and seasonal variation (wet, dry) at a California landfill. The majority of the F-gas fluxes was positive and varied over 7 orders of magnitude across the cover types in a given season (wet: 10-8 to 10-1 g/m2-day; dry: 10-9 to 10-2 g/m2-day). The highest fluxes were from active filling areas with thin, coarse-grained daily covers, whereas the lowest fluxes were from the thick, fine-grained final cover. Historical F-gas replacement trends, waste age, and cover soil geotechnical properties affected flux with significantly lower F-gas fluxes than methane flux (10-4 to 10+1 g/m2-day). Both flux and variability of flux decreased with the order: daily to intermediate to final covers; coarser to finer cover materials; low to high fines content cover soils; high to low degree of saturation cover soils; and thin to thick covers. Cover-specific F-gas fluxes were approximately one order of magnitude higher in the wet than dry season, due to combined effects of comparatively high saturations, high void ratios, and low temperatures. Emissions were primarily controlled by type and relative areal extent of cover materials and secondarily by season.
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Affiliation(s)
- Nazlı Yeşiller
- Civil and Environmental Engineering Department , California Polytechnic State University , San Luis Obispo , California 93407 , United States
| | - James L Hanson
- Civil and Environmental Engineering Department , California Polytechnic State University , San Luis Obispo , California 93407 , United States
| | - Alexander H Sohn
- Civil and Environmental Engineering Department , California Polytechnic State University , San Luis Obispo , California 93407 , United States
| | - Jean E Bogner
- Department of Earth and Environmental Sciences , University of Illinois at Chicago , Chicago , Illinois 60607 , United States
| | - Donald R Blake
- Department of Chemistry , University of California-Irvine , Irvine , California 92697 , United States
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Liu Y, Lu W, Dastyar W, Liu Y, Guo H, Fu X, Li H, Meng R, Zhao M, Wang H. Fugitive halocarbon emissions from working face of municipal solid waste landfills in China. WASTE MANAGEMENT (NEW YORK, N.Y.) 2017; 70:149-157. [PMID: 28917825 DOI: 10.1016/j.wasman.2017.08.042] [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: 05/03/2017] [Revised: 07/30/2017] [Accepted: 08/23/2017] [Indexed: 06/07/2023]
Abstract
Halocarbons are important anthropogenic greenhouse gases (GHGs) due to their long lifetime and large characteristic factors. The present study for the first time assessed the global warming potential (GWP) of fugitive halocarbon emissions from the working face of landfills in China. The national emissions of five major halocarbons (CFC-11, CFC-113, CH2Cl2, CHCl3 and CCl4) from the working face of municipal solid waste landfills in China were provided through observation-based estimations. The fluxes of halocarbons from working face of landfills were observed much higher than covered cells in landfills hence representing the hot spots of landfill emissions. The annual emissions of the halocarbons from landfills in China were 0.02-15.6kt·y-1, and their GWPs were 128-60,948kt-CO2-eq·y-1 based on their characteristic factors on a 100-year horizon. CFC-113 was the dominant species owing to its highest releasing rate (i.e. 15.4±19.1g·t-1) and largest characteristic factor, resulting in a GWP up to 4036±4855kt-CO2-eq·y-1. The annual emissions of CFC-113 from landfills (i.e. 0.61kt·y-1) made up ∼76% of the total national CFC-113 emissions. The GWPs of halocarbons were estimated ∼14.4% of landfill methane emissions. Therefore, fugitive halocarbons emissions from working face are significant sources of GHGs in landfill sites in China, although they comprise a small fraction of total landfill gases.
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Affiliation(s)
- Yanjun Liu
- School of Environment, Tsinghua University, Beijing 10084, China; State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
| | - Wenjing Lu
- School of Environment, Tsinghua University, Beijing 10084, China; Key Laboratory for Solid Waste Management and Environment Safety, Ministry of Education of China, Tsinghua University, Beijing 100084, China
| | - Wafa Dastyar
- School of Environment, Tsinghua University, Beijing 10084, China; Key Laboratory for Solid Waste Management and Environment Safety, Ministry of Education of China, Tsinghua University, Beijing 100084, China
| | - Yanting Liu
- School of Environment, Tsinghua University, Beijing 10084, China; Key Laboratory for Solid Waste Management and Environment Safety, Ministry of Education of China, Tsinghua University, Beijing 100084, China
| | - Hanwen Guo
- School of Environment, Tsinghua University, Beijing 10084, China; Key Laboratory for Solid Waste Management and Environment Safety, Ministry of Education of China, Tsinghua University, Beijing 100084, China
| | - Xindi Fu
- School of Environment, Tsinghua University, Beijing 10084, China; Key Laboratory for Solid Waste Management and Environment Safety, Ministry of Education of China, Tsinghua University, Beijing 100084, China
| | - Hao Li
- School of Environment, Tsinghua University, Beijing 10084, China; Key Laboratory for Solid Waste Management and Environment Safety, Ministry of Education of China, Tsinghua University, Beijing 100084, China
| | - Ruihong Meng
- School of Environment, Tsinghua University, Beijing 10084, China; Key Laboratory for Solid Waste Management and Environment Safety, Ministry of Education of China, Tsinghua University, Beijing 100084, China
| | - Ming Zhao
- School of Environment, Tsinghua University, Beijing 10084, China; Key Laboratory for Solid Waste Management and Environment Safety, Ministry of Education of China, Tsinghua University, Beijing 100084, China.
| | - Hongtao Wang
- School of Environment, Tsinghua University, Beijing 10084, China; Key Laboratory for Solid Waste Management and Environment Safety, Ministry of Education of China, Tsinghua University, Beijing 100084, China.
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Continued emissions of carbon tetrachloride from the United States nearly two decades after its phaseout for dispersive uses. Proc Natl Acad Sci U S A 2016; 113:2880-5. [PMID: 26929368 DOI: 10.1073/pnas.1522284113] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
National-scale emissions of carbon tetrachloride (CCl4) are derived based on inverse modeling of atmospheric observations at multiple sites across the United States from the National Oceanic and Atmospheric Administration's flask air sampling network. We estimate an annual average US emission of 4.0 (2.0-6.5) Gg CCl4 y(-1) during 2008-2012, which is almost two orders of magnitude larger than reported to the US Environmental Protection Agency (EPA) Toxics Release Inventory (TRI) (mean of 0.06 Gg y(-1)) but only 8% (3-22%) of global CCl4 emissions during these years. Emissive regions identified by the observations and consistently shown in all inversion results include the Gulf Coast states, the San Francisco Bay Area in California, and the Denver area in Colorado. Both the observation-derived emissions and the US EPA TRI identified Texas and Louisiana as the largest contributors, accounting for one- to two-thirds of the US national total CCl4 emission during 2008-2012. These results are qualitatively consistent with multiple aircraft and ship surveys conducted in earlier years, which suggested significant enhancements in atmospheric mole fractions measured near Houston and surrounding areas. Furthermore, the emission distribution derived for CCl4 throughout the United States is more consistent with the distribution of industrial activities included in the TRI than with the distribution of other potential CCl4 sources such as uncapped landfills or activities related to population density (e.g., use of chlorine-containing bleach).
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Global emissions of refrigerants HCFC-22 and HFC-134a: unforeseen seasonal contributions. Proc Natl Acad Sci U S A 2014; 111:17379-84. [PMID: 25422438 DOI: 10.1073/pnas.1417372111] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
HCFC-22 (CHClF2) and HFC-134a (CH2FCF3) are two major gases currently used worldwide in domestic and commercial refrigeration and air conditioning. HCFC-22 contributes to stratospheric ozone depletion, and both species are potent greenhouse gases. In this work, we study in situ observations of HCFC-22 and HFC-134a taken from research aircraft over the Pacific Ocean in a 3-y span [HIaper-Pole-to-Pole Observations (HIPPO) 2009-2011] and combine these data with long-term ground observations from global surface sites [National Oceanic and Atmospheric Administration (NOAA) and Advanced Global Atmospheric Gases Experiment (AGAGE) networks]. We find the global annual emissions of HCFC-22 and HFC-134a have increased substantially over the past two decades. Emissions of HFC-134a are consistently higher compared with the United Nations Framework Convention on Climate Change (UNFCCC) inventory since 2000, by 60% more in recent years (2009-2012). Apart from these decadal emission constraints, we also quantify recent seasonal emission patterns showing that summertime emissions of HCFC-22 and HFC-134a are two to three times higher than wintertime emissions. This unforeseen large seasonal variation indicates that unaccounted mechanisms controlling refrigerant gas emissions are missing in the existing inventory estimates. Possible mechanisms enhancing refrigerant losses in summer are (i) higher vapor pressure in the sealed compartment of the system at summer high temperatures and (ii) more frequent use and service of refrigerators and air conditioners in summer months. Our results suggest that engineering (e.g., better temperature/vibration-resistant system sealing and new system design of more compact/efficient components) and regulatory (e.g., reinforcing system service regulations) steps to improve containment of these gases from working devices could effectively reduce their release to the atmosphere.
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Gallagher G, Zhan T, Hsu YK, Gupta P, Pederson J, Croes B, Blake DR, Barletta B, Meinardi S, Ashford P, Vetter A, Saba S, Slim R, Palandre L, Clodic D, Mathis P, Wagner M, Forgie J, Dwyer H, Wolf K. High-global warming potential F-gas emissions in California: comparison of ambient-based versus inventory-based emission estimates, and implications of refined estimates. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2014; 48:1084-1093. [PMID: 24328112 DOI: 10.1021/es403447v] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
To provide information for greenhouse gas reduction policies, the California Air Resources Board (CARB) inventories annual emissions of high-global-warming potential (GWP) fluorinated gases, the fastest growing sector of greenhouse gas (GHG) emissions globally. Baseline 2008 F-gas emissions estimates for selected chlorofluorocarbons (CFC-12), hydrochlorofluorocarbons (HCFC-22), and hydrofluorocarbons (HFC-134a) made with an inventory-based methodology were compared to emissions estimates made by ambient-based measurements. Significant discrepancies were found, with the inventory-based emissions methodology resulting in a systematic 42% under-estimation of CFC-12 emissions from older refrigeration equipment and older vehicles, and a systematic 114% overestimation of emissions for HFC-134a, a refrigerant substitute for phased-out CFCs. Initial, inventory-based estimates for all F-gas emissions had assumed that equipment is no longer in service once it reaches its average lifetime of use. Revised emission estimates using improved models for equipment age at end-of-life, inventories, and leak rates specific to California resulted in F-gas emissions estimates in closer agreement to ambient-based measurements. The discrepancies between inventory-based estimates and ambient-based measurements were reduced from -42% to -6% for CFC-12, and from +114% to +9% for HFC-134a.
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Affiliation(s)
- Glenn Gallagher
- California Air Resources Board, 1001 I Street, Sacramento, California 95814, United States
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Assessment of theoretical methods for the study of hydrogen abstraction kinetics of global warming gas species during their degradation and byproduct formation (IUPAC Technical Report). PURE APPL CHEM 2013. [DOI: 10.1351/pac-rep-10-02-38] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Global climate change is a major concern as it leads to an increase in the
average temperature of the earth’s atmosphere. The existence and
persistence of some gaseous species in the atmosphere contribute to global
warming. Experimental techniques are used to study the kinetics and degradation
of global warming gases. However, quantum mechanical methods are also useful for
the kinetic and radiative forcing study of global warming species and can
precede experimental investigations. Research has also been targeted to develop
more adapted procedures using ab initio and density functional theory (DFT)
methods. This report provides a global perspective, in simplified manner, of the
theoretical studies of the degradation of gas species in the atmosphere with an
emphasis on the hydrogen abstraction kinetics of global warming gas species
during their degradation and byproduct formation. En route, the results obtained
from these studies are analysed and compared with experimental data where
available. Our analyses indicate that the theoretical predictions are in
agreement with experimental findings but the predicted parameters are dependent
on the method being used. Theoretical methods are used to predict the
thermodynamic parameters of reactions, and, with relevance to this report, the
global warming potential (GWP) index can also be calculated. This report can be
useful for future investigations involving global warming gaseous species while
providing suggestions on how computations can fill in data gaps when
experimental data are unavailable.
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Keller CA, Hill M, Vollmer MK, Henne S, Brunner D, Reimann S, O'Doherty S, Arduini J, Maione M, Ferenczi Z, Haszpra L, Manning AJ, Peter T. European emissions of halogenated greenhouse gases inferred from atmospheric measurements. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2012; 46:217-225. [PMID: 22192076 DOI: 10.1021/es202453j] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
European emissions of nine representative halocarbons (CFC-11, CFC-12, Halon 1211, HCFC-141b, HCFC-142b, HCFC-22, HFC-125, HFC-134a, HFC-152a) are derived for the year 2009 by combining long-term observations in Switzerland, Italy, and Ireland with campaign measurements from Hungary. For the first time, halocarbon emissions over Eastern Europe are assessed by top-down methods, and these results are compared to Western European emissions. The employed inversion method builds on least-squares optimization linking atmospheric observations with calculations from the Lagrangian particle dispersion model FLEXPART. The aggregated halocarbon emissions over the study area are estimated at 125 (106-150) Tg of CO(2) equiv/y, of which the hydrofluorocarbons (HFCs) make up the most important fraction with 41% (31-52%). We find that chlorofluorocarbon (CFC) emissions from banks are still significant and account for 35% (27-43%) of total halocarbon emissions in Europe. The regional differences in per capita emissions are only small for the HFCs, while emissions of CFCs and hydrochlorofluorocarbons (HCFCs) tend to be higher in Western Europe compared to Eastern Europe. In total, the inferred per capita emissions are similar to estimates for China, but 3.5 (2.3-4.5) times lower than for the United States. Our study demonstrates the large benefits of adding a strategically well placed measurement site to the existing European observation network of halocarbons, as it extends the coverage of the inversion domain toward Eastern Europe and helps to better constrain the emissions over Central Europe.
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Affiliation(s)
- Christoph A Keller
- Laboratory for Air Pollution/Environmental Technology, Swiss Federal Laboratories for Materials Science and Technology (Empa), Duebendorf, Switzerland.
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10
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Tang X, Wilson SR, Solomon KR, Shao M, Madronich S. Changes in air quality and tropospheric composition due to depletion of stratospheric ozone and interactions with climate. Photochem Photobiol Sci 2011; 10:280-91. [DOI: 10.1039/c0pp90039g] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Ponette-González AG, Weathers KC, Curran LM. Tropical land-cover change alters biogeochemical inputs to ecosystems in a Mexican montane landscape. ECOLOGICAL APPLICATIONS : A PUBLICATION OF THE ECOLOGICAL SOCIETY OF AMERICA 2010; 20:1820-1837. [PMID: 21049872 DOI: 10.1890/09-1125.1] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/30/2023]
Abstract
In tropical regions, the effects of land-cover change on nutrient and pollutant inputs to ecosystems remain poorly documented and may be pronounced, especially in montane areas exposed to elevated atmospheric deposition. We examined atmospheric deposition and canopy interactions of sulfate-sulfur (SO4(2-)-S), chloride (Cl-), and nitrate-nitrogen (NO(3-)-N) in three extensive tropical montane land-cover types: clearings, forest, and coffee agroforest. Bulk and fog deposition to clearings was measured as well as throughfall (water that falls through plant canopies) ion fluxes in seven forest and five coffee sites. Sampling was conducted from 2005 to 2008 across two regions in the Sierra Madre Oriental, Veracruz, Mexico. Annual throughfall fluxes to forest and coffee sites ranged over 6-27 kg SO4(2-)-S/ha, 12-69 kg Cl-/ha, and 2-6 kg NO(3-)-N/ha. Sulfate-S in forest and coffee throughfall was higher or similar to bulk S deposition measured in clearings. Throughfall Cl- inputs, however, were consistently higher than Cl- amounts deposited to cleared areas, with net Cl- fluxes enhanced in evergreen coffee relative to semi-deciduous forest plots. Compared to bulk nitrate-N deposition, forest and coffee canopies retained 1-4 kg NO(3-)-N/ha annually, reducing NO(3-)-N inputs to soils. Overall, throughfall fluxes were similar to values reported for Neotropical sites influenced by anthropogenic emissions, while bulk S and N deposition were nine- and eightfold greater, respectively, than background wet deposition rates for remote tropical areas. Our results demonstrate that land-cover type significantly alters the magnitude and spatial distribution of atmospheric inputs to tropical ecosystems, primarily through canopy-induced changes in fog and dry deposition. However, we found that land cover interacts with topography and climate in significant ways to produce spatially heterogeneous patterns of anion fluxes, and that these factors can converge to create deposition hotspots. For land managers, this finding suggests that there is potential to identify species and ecosystems at risk of excess and increasing deposition in montane watersheds undergoing rapid transformation. Our data further indicate that montane ecosystems are vulnerable to air pollution impacts in this and similar tropical regions downwind of urban, industrial, and agricultural emission sources.
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Affiliation(s)
- A G Ponette-González
- Yale School of Forestry and Environmental Studies, 210 Prospect Street, New Haven, Connecticut 06511, USA.
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12
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Zhang YL, Guo H, Wang XM, Simpson IJ, Barletta B, Blake DR, Meinardi S, Rowland FS, Cheng HR, Saunders SM, Lam SHM. Emission patterns and spatiotemporal variations of halocarbons in the Pearl River Delta region, southern China. ACTA ACUST UNITED AC 2010. [DOI: 10.1029/2009jd013726] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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13
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Gentner DR, Miller AM, Goldstein AH. Seasonal variability in anthropogenic halocarbon emissions. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2010; 44:5377-5382. [PMID: 20536226 DOI: 10.1021/es1005362] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Ambient concentrations of eight predominantly anthropogenic halocarbons were measured via in situ gas chromatography in California's South Coast air basin for both summer and fall during the 2005 Study of Organic Aerosols at Riverside (SOAR). Ongoing emissions of the banned halocarbons methylchloroform and CFC-11 were observed in the South Coast air basin, whereas CFC-113 emissions have effectively ceased. We estimate anthropogenic emissions in the South Coast air basin for methylchloroform, CFC-11, HCFC-141b, chloroform, tetrachloroethene (PCE), trichloroethylene (TCE), and dichloromethane based on regressions of halocarbon to carbon monoxide mixing ratios and carbon monoxide emission inventories. We estimate per capita methylchloroform and chloroform emissions in the South Coast air basin for the year 2005 to be 6.6 +/- 0.4 g/(person.year) and 19 +/- 1 g/(person.year), respectively. We compare our results to national emission estimates calculated from previous work; for several compounds, emissions in the South Coast air basin are significantly lower than national per capita emissions. We observed strong seasonal differences in anthropogenic emissions of methylchloroform and chloroform; emissions were 4.5 and 2.5 times greater in summer than in fall, respectively. Possible seasonal sources include landfills and water chlorination. We conclude that seasonal variability in methylchloroform emissions has not been included in previous inventories and may cause errors in methylchloroform emission estimates after the year 2000 and seasonally resolved inversion calculations of hydroxyl radical abundance.
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Affiliation(s)
- Drew R Gentner
- Department of Civil and Environmental Engineering, University of California, Berkeley, California 94720, USA
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Andrady A, Aucamp PJ, Bais AF, Ballaré CL, Björn LO, Bornman JF, Caldwell M, Cullen AP, Erickson DJ, deGruijl FR, Häder DP, Ilyas M, Kulandaivelu G, Kumar HD, Longstreth J, McKenzie RL, Norval M, Paul N, Redhwi HH, Smith RC, Solomon KR, Sulzberger B, Takizawa Y, Tang X, Teramura AH, Torikai A, van der Leun JC, Wilson SR, Worrest RC, Zepp RG. Environmental effects of ozone depletion and its interactions with climate change: progress report, 2009. Photochem Photobiol Sci 2010; 9:275-94. [PMID: 20301813 DOI: 10.1039/b923342n] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The parties to the Montreal Protocol are informed by three panels of experts. One of these is the Environmental Effects Assessment Panel (EEAP), which deals with UV radiation and its effects on human health, animals, plants, biogeochemistry, air quality and materials. Since 2000, the analyses and interpretation of these effects have included interactions between UV radiation and global climate change. When considering the effects of climate change, it has become clear that processes resulting in changes in stratospheric ozone are more complex than believed previously. As a result of this, human health and environmental problems will likely be longer-lasting and more regionally variable. Like the other panels, the EEAP produces a detailed report every four years; the most recent was that for 2006 (Photochem. Photobiol. Sci., 2007, 6, 201-332). In the years in between, the EEAP produces a less detailed and shorter progress report, as is the case for this present one for 2009. A full quadrennial report will follow for 2010.
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