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Yang L, Nie W, Liu Y, Xu Z, Xiao M, Qi X, Li Y, Wang R, Zou J, Paasonen P, Yan C, Xu Z, Wang J, Zhou C, Yuan J, Sun J, Chi X, Kerminen VM, Kulmala M, Ding A. Toward Building a Physical Proxy for Gas-Phase Sulfuric Acid Concentration Based on Its Budget Analysis in Polluted Yangtze River Delta, East China. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2021; 55:6665-6676. [PMID: 33960763 PMCID: PMC8154357 DOI: 10.1021/acs.est.1c00738] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/01/2021] [Revised: 04/11/2021] [Accepted: 04/21/2021] [Indexed: 05/17/2023]
Abstract
Gaseous sulfuric acid (H2SO4) is a crucial precursor for secondary aerosol formation, particularly for new particle formation (NPF) that plays an essential role in the global number budget of aerosol particles and cloud condensation nuclei. Due to technology challenges, global-wide and long-term measurements of gaseous H2SO4 are currently very challenging. Empirical proxies for H2SO4 have been derived mainly based on short-term intensive campaigns. In this work, we performed comprehensive measurements of H2SO4 and related parameters in the polluted Yangtze River Delta in East China during four seasons and developed a physical proxy based on the budget analysis of gaseous H2SO4. Besides the photo-oxidation of SO2, we found that primary emissions can contribute considerably, particularly at night. Dry deposition has the potential to be a non-negligible sink, in addition to condensation onto particle surfaces. Compared with the empirical proxies, the newly developed physical proxy demonstrates extraordinary stability in all the seasons and has the potential to be widely used to improve the understanding of global NPF fundamentally.
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Affiliation(s)
- Liwen Yang
- Joint
International Research Laboratory of Atmospheric and Earth System
Sciences, School of Atmospheric Sciences, Nanjing University, Nanjing 210023, China
- Jiangsu
Provincial Collaborative Innovation Center of Climate Change, Nanjing, 210023, China
| | - Wei Nie
- Joint
International Research Laboratory of Atmospheric and Earth System
Sciences, School of Atmospheric Sciences, Nanjing University, Nanjing 210023, China
- Jiangsu
Provincial Collaborative Innovation Center of Climate Change, Nanjing, 210023, China
| | - Yuliang Liu
- Joint
International Research Laboratory of Atmospheric and Earth System
Sciences, School of Atmospheric Sciences, Nanjing University, Nanjing 210023, China
- Jiangsu
Provincial Collaborative Innovation Center of Climate Change, Nanjing, 210023, China
| | - Zhengning Xu
- Joint
International Research Laboratory of Atmospheric and Earth System
Sciences, School of Atmospheric Sciences, Nanjing University, Nanjing 210023, China
- Jiangsu
Provincial Collaborative Innovation Center of Climate Change, Nanjing, 210023, China
| | - Mao Xiao
- Laboratory
of Atmospheric Chemistry, Paul Scherrer
Institute, 5232 Villigen, Switzerland
| | - Ximeng Qi
- Joint
International Research Laboratory of Atmospheric and Earth System
Sciences, School of Atmospheric Sciences, Nanjing University, Nanjing 210023, China
- Jiangsu
Provincial Collaborative Innovation Center of Climate Change, Nanjing, 210023, China
| | - Yuanyuan Li
- Joint
International Research Laboratory of Atmospheric and Earth System
Sciences, School of Atmospheric Sciences, Nanjing University, Nanjing 210023, China
- Jiangsu
Provincial Collaborative Innovation Center of Climate Change, Nanjing, 210023, China
| | - Ruoxian Wang
- Joint
International Research Laboratory of Atmospheric and Earth System
Sciences, School of Atmospheric Sciences, Nanjing University, Nanjing 210023, China
- Jiangsu
Provincial Collaborative Innovation Center of Climate Change, Nanjing, 210023, China
| | - Jun Zou
- Joint
International Research Laboratory of Atmospheric and Earth System
Sciences, School of Atmospheric Sciences, Nanjing University, Nanjing 210023, China
- Jiangsu
Provincial Collaborative Innovation Center of Climate Change, Nanjing, 210023, China
| | - Pauli Paasonen
- Institute
for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, 00014 Helsinki, Finland
| | - Chao Yan
- Institute
for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, 00014 Helsinki, Finland
| | - Zheng Xu
- Joint
International Research Laboratory of Atmospheric and Earth System
Sciences, School of Atmospheric Sciences, Nanjing University, Nanjing 210023, China
- Jiangsu
Provincial Collaborative Innovation Center of Climate Change, Nanjing, 210023, China
| | - Jiaping Wang
- Joint
International Research Laboratory of Atmospheric and Earth System
Sciences, School of Atmospheric Sciences, Nanjing University, Nanjing 210023, China
- Jiangsu
Provincial Collaborative Innovation Center of Climate Change, Nanjing, 210023, China
| | - Chen Zhou
- Joint
International Research Laboratory of Atmospheric and Earth System
Sciences, School of Atmospheric Sciences, Nanjing University, Nanjing 210023, China
- Jiangsu
Provincial Collaborative Innovation Center of Climate Change, Nanjing, 210023, China
| | - Jian Yuan
- Joint
International Research Laboratory of Atmospheric and Earth System
Sciences, School of Atmospheric Sciences, Nanjing University, Nanjing 210023, China
- Jiangsu
Provincial Collaborative Innovation Center of Climate Change, Nanjing, 210023, China
| | - Jianning Sun
- Joint
International Research Laboratory of Atmospheric and Earth System
Sciences, School of Atmospheric Sciences, Nanjing University, Nanjing 210023, China
- Jiangsu
Provincial Collaborative Innovation Center of Climate Change, Nanjing, 210023, China
| | - Xuguang Chi
- Joint
International Research Laboratory of Atmospheric and Earth System
Sciences, School of Atmospheric Sciences, Nanjing University, Nanjing 210023, China
- Jiangsu
Provincial Collaborative Innovation Center of Climate Change, Nanjing, 210023, China
| | - Veli-Matti Kerminen
- Joint
International Research Laboratory of Atmospheric and Earth System
Sciences, School of Atmospheric Sciences, Nanjing University, Nanjing 210023, China
- Institute
for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, 00014 Helsinki, Finland
| | - Markku Kulmala
- Joint
International Research Laboratory of Atmospheric and Earth System
Sciences, School of Atmospheric Sciences, Nanjing University, Nanjing 210023, China
- Institute
for Atmospheric and Earth System Research/Physics, Faculty of Science, University of Helsinki, 00014 Helsinki, Finland
| | - Aijun Ding
- Joint
International Research Laboratory of Atmospheric and Earth System
Sciences, School of Atmospheric Sciences, Nanjing University, Nanjing 210023, China
- Jiangsu
Provincial Collaborative Innovation Center of Climate Change, Nanjing, 210023, China
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Zempila MM, Taylor M, Koukouli ME, Lerot C, Fragkos K, Fountoulakis I, Bais A, Balis D, van Roozendael M. NILU-UV multi-filter radiometer total ozone columns: Comparison with satellite observations over Thessaloniki, Greece. THE SCIENCE OF THE TOTAL ENVIRONMENT 2017; 590-591:92-106. [PMID: 28259430 DOI: 10.1016/j.scitotenv.2017.02.174] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2016] [Revised: 02/01/2017] [Accepted: 02/21/2017] [Indexed: 06/06/2023]
Abstract
This study aims to construct and validate a neural network (NN) model for the production of high frequency (~1min) ground-based estimates of total ozone column (TOC) at a mid-latitude UV and ozone monitoring station in the Laboratory of Atmospheric Physics of the Aristotle University of Thessaloniki (LAP/AUTh) for the years 2005-2014. In the first stage of model development, ~30,000 records of coincident solar UV spectral irradiance measurements from a Norsk Institutt for Luftforskning (NILU)-UV multi-filter radiometer and TOC measurements from a co-located Brewer spectroradiometer are used to train a NN to learn the nonlinear functional relation between the irradiances and TOC. The model is then subjected to sensitivity analysis and validation. Close agreement is obtained (R2=0.94, RMSE=8.21 DU and bias=-0.15 DU relative to the Brewer) for the training data in the correlation of NN estimates on Brewer derived TOC with 95% of the coincident data differing by less than 13 DU. In the second stage of development, a long time series (≥1 million records) of high frequency (~1min) NILU-UV ground-based measurements are presented as inputs to the NN model to generate high frequency TOC estimates. The advantage of the NN model is that it is not site dependent and is applicable to any NILU input data lying within the range of the training data. GOME/ERS-2, SCIAMACHY/Envisat, OMI/Aura and GOME2/MetOp-A TOC records are then used to perform a precise cross-validation analysis and comparison with the NILU TOC estimates over Thessaloniki. All 4 satellite TOC dataset are retrieved using the GOME Direct Fitting algorithm, version 3 (GODFIT_v3), for reasons of consistency. The NILU TOC estimates within ±30min of the overpass times agree well with the satellite TOC retrievals with coefficient of determination in the range 0.88≤R2≤0.90 for all sky conditions and 0.95≤R2≤0.96 for clear sky conditions. The mean fractional differences are found to be -0.67%±2.15%, -1.44%±2.25%, -2.09%±2.06% and -0.85%±2.19% for GOME, SCIAMACHY, OMI and GOME2 respectively for the clear sky cases. The near constant standard deviation (~±2.2%) across the array of sensors testifies directly to the stability of both the GODFIT_v3 algorithm and the NN model for providing coherent and robust TOC records. Furthermore, the high Pearson product moment correlation coefficients (0.94<R<0.98) testify to the strength of the linear relationship between the satellite algorithm retrievals of TOC and ground-based estimates, while biases of less than 5 DU suggest that systematic errors are low. This novel methodology contributes to the ongoing assessment of the quality and consistency of ground and space-based measurements of total ozone columns.
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Affiliation(s)
- Melina Maria Zempila
- USDA UV-B Monitoring and Research Program, Colorado State University, Fort Collins, CO 80523, USA; Laboratory of Atmospheric Physics, Aristotle University of Thessaloniki, PO Box 149, 54124 Thessaloniki, Greece.
| | - Michael Taylor
- Laboratory of Atmospheric Physics, Aristotle University of Thessaloniki, PO Box 149, 54124 Thessaloniki, Greece
| | - Maria Elissavet Koukouli
- Laboratory of Atmospheric Physics, Aristotle University of Thessaloniki, PO Box 149, 54124 Thessaloniki, Greece
| | - Christophe Lerot
- Belgian Institute for Space Aeronomy, BIRA-IASB, Brussels, Belgium
| | - Konstantinos Fragkos
- Laboratory of Atmospheric Physics, Aristotle University of Thessaloniki, PO Box 149, 54124 Thessaloniki, Greece
| | - Ilias Fountoulakis
- Laboratory of Atmospheric Physics, Aristotle University of Thessaloniki, PO Box 149, 54124 Thessaloniki, Greece
| | - Alkiviadis Bais
- Laboratory of Atmospheric Physics, Aristotle University of Thessaloniki, PO Box 149, 54124 Thessaloniki, Greece
| | - Dimitrios Balis
- Laboratory of Atmospheric Physics, Aristotle University of Thessaloniki, PO Box 149, 54124 Thessaloniki, Greece
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Gerasopoulos E, Kazadzis S, Vrekoussis M, Kouvarakis G, Liakakou E, Kouremeti N, Giannadaki D, Kanakidou M, Bohn B, Mihalopoulos N. Factors affecting O3and NO2photolysis frequencies measured in the eastern Mediterranean during the five-year period 2002-2006. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/2012jd017622] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Rius SP, Grotewold E, Casati P. Analysis of the P1 promoter in response to UV-B radiation in allelic variants of high-altitude maize. BMC PLANT BIOLOGY 2012; 12:92. [PMID: 22702356 PMCID: PMC3489873 DOI: 10.1186/1471-2229-12-92] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2012] [Accepted: 05/28/2012] [Indexed: 05/18/2023]
Abstract
BACKGROUND Plants living at high altitudes are typically exposed to elevated UV-B radiation, and harbor mechanisms to prevent the induced damage, such as the accumulation of UV-absorbing compounds. The maize R2R3-MYB transcription factor P1 controls the accumulation of several UV-B absorbing phenolics by activating a subset of flavonoid biosynthetic genes in leaves of maize landraces adapted to high altitudes. RESULTS Here, we studied the UV-B regulation of P1 in maize leaves of high altitude landraces, and we investigated how UV-B regulates P1 binding to the CHS promoter in both low and high altitude lines. In addition, we analyzed whether the expansion in the P1 expression domain between these maize landraces and inbred lines is associated to changes in the molecular structure of the proximal promoter, distal enhancer and first intron of P1. Finally, using transient expression experiments in protoplasts from various maize genotypes, we investigated whether the different expression patterns of P1 in the high altitude landraces could be attributed to trans- or cis-acting elements. CONCLUSIONS Together, our results demonstrate that, although differences in cis-acting elements exist between the different lines under study, the different patterns of P1 expression are largely a consequence of effects in trans.
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Affiliation(s)
- Sebastián Pablo Rius
- Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI), Universidad Nacional de Rosario, Suipacha 531, Rosario, Argentina
| | - Erich Grotewold
- Plant Biotechnology Center, The Ohio State University, Columbus, OH, 43210, USA
- Department of Plant Cellular and Molecular Biology, The Ohio State University, Columbus, OH, 43210, USA
| | - Paula Casati
- Centro de Estudios Fotosintéticos y Bioquímicos (CEFOBI), Universidad Nacional de Rosario, Suipacha 531, Rosario, Argentina
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Testing the applicability of artificial intelligence techniques to the subject of erythemal ultraviolet solar radiation. Part two: an intelligent system based on multi-classifier technique. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY. B, BIOLOGY 2008; 90:198-206. [PMID: 18280747 DOI: 10.1016/j.jphotobiol.2007.12.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2007] [Revised: 11/02/2007] [Accepted: 12/02/2007] [Indexed: 11/23/2022]
Abstract
The problem we address here describes the on-going research effort that takes place to shed light on the applicability of using artificial intelligence techniques to predict the local noon erythemal UV irradiance in the plain areas of Egypt. In light of this fact, we use the bootstrap aggregating (bagging) algorithm to improve the prediction accuracy reported by a multi-layer perceptron (MLP) network. The results showed that, the overall prediction accuracy for the MLP network was only 80.9%. When bagging algorithm is used, the accuracy reached 94.8%; an improvement of about 13.9% was achieved. These improvements demonstrate the efficiency of the bagging procedure, and may be used as a promising tool at least for the plain areas of Egypt.
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Lin W, Zhu T, Song Y, Zou H, Tang M, Tang X, Hu J. Photolysis of surface O3and production potential of OH radicals in the atmosphere over the Tibetan Plateau. ACTA ACUST UNITED AC 2008. [DOI: 10.1029/2007jd008831] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Bossioli E, Tombrou M, Dandou A, Soulakellis N. Simulation of the effects of critical factors on ozone formation and accumulation in the greater Athens area. ACTA ACUST UNITED AC 2007. [DOI: 10.1029/2006jd007185] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Varotsos CA, Ondov JM, Cracknell AP, Efstathiou MN, Assimakopoulos M. Long‐range persistence in global Aerosol Index dynamics. INTERNATIONAL JOURNAL OF REMOTE SENSING 2006; 27:3593-3603. [DOI: 10.1080/01431160600617236] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/16/2023]
Affiliation(s)
- C. A. Varotsos
- a Department of Atmospheric and Oceanic Science , University of Maryland , College Park, MD 20742, USA
- d Department of Applied Physics , University of Athens , Panepistimiopolis , Bldg Phys. 5, ATH 15784, Greece
| | - J. M. Ondov
- b Department of Chemistry and Biochemistry , University of Maryland , College Park, MD 20742, USA
| | - A. P. Cracknell
- c Division of Electronic Engineering and Physics , University of Dundee , Dundee DD1 4HN, UK
| | - M. N. Efstathiou
- d Department of Applied Physics , University of Athens , Panepistimiopolis , Bldg Phys. 5, ATH 15784, Greece
| | - M.‐N. Assimakopoulos
- d Department of Applied Physics , University of Athens , Panepistimiopolis , Bldg Phys. 5, ATH 15784, Greece
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Casati P, Stapleton AE, Blum JE, Walbot V. Genome-wide analysis of high-altitude maize and gene knockdown stocks implicates chromatin remodeling proteins in response to UV-B. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2006; 46:613-27. [PMID: 16640598 DOI: 10.1111/j.1365-313x.2006.02721.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
A comparative analysis, by expression profiling of maize, was performed to identify novel components in the mechanisms of maize responses to UV-B. Five high-altitude landraces grown from 2,000 to 3,400 m naturally receive higher UV-B fluence than plants at lower altitudes and similar latitudes. These high-altitude landraces were compared directly with a low-altitude line and with literature reports for other temperate maize lines. A microarray analysis demonstrated that among the UV-B responsive transcripts, several types of gene implicated in chromatin remodeling are differentially expressed before and after UV-B treatment in high-altitude lines. RNAi transgenic plants with lower expression of four such chromatin-associated genes exhibited hypersensitivity to UV-B by measurements of leaf arching, increased leaf chlorosis and necrosis, and altered UV-B regulation of selected genes. These results collectively suggest that genes involved in chromatin remodeling are crucial for UV-B acclimation and that some high-altitude lines exhibit adaptations to this challenge.
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Affiliation(s)
- Paula Casati
- Department of Biological Sciences, Stanford University, 385 Serra Mall, Stanford, CA 94305-5020, USA.
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Pérez C, Nickovic S, Baldasano JM, Sicard M, Rocadenbosch F, Cachorro VE. A long Saharan dust event over the western Mediterranean: Lidar, Sun photometer observations, and regional dust modeling. ACTA ACUST UNITED AC 2006. [DOI: 10.1029/2005jd006579] [Citation(s) in RCA: 233] [Impact Index Per Article: 12.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Lefer BL, Shetter RE, Hall SR, Crawford JH, Olson JR. Impact of clouds and aerosols on photolysis frequencies and photochemistry during TRACE-P: 1. Analysis using radiative transfer and photochemical box models. ACTA ACUST UNITED AC 2003. [DOI: 10.1029/2002jd003171] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- B. L. Lefer
- National Center for Atmospheric Research; Boulder Colorado USA
| | - R. E. Shetter
- National Center for Atmospheric Research; Boulder Colorado USA
| | - S. R. Hall
- National Center for Atmospheric Research; Boulder Colorado USA
| | | | - J. R. Olson
- NASA Langley Research Center; Hampton Virginia USA
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Bian H, Zender CS. Mineral dust and global tropospheric chemistry: Relative roles of photolysis and heterogeneous uptake. ACTA ACUST UNITED AC 2003. [DOI: 10.1029/2002jd003143] [Citation(s) in RCA: 106] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Huisheng Bian
- Department of Earth System Science; University of California at Irvine; Irvine California USA
| | - Charles S. Zender
- Department of Earth System Science; University of California at Irvine; Irvine California USA
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Meloni D. Tropospheric aerosols in the Mediterranean: 3. Measurements and modeling of actinic radiation profiles. ACTA ACUST UNITED AC 2003. [DOI: 10.1029/2002jd003293] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Solomon KR, Tang X, Wilson SR, Zanis P, Bais AF. Changes in tropospheric composition and air quality due to stratospheric ozone depletion. Photochem Photobiol Sci 2003; 2:62-7. [PMID: 12659540 DOI: 10.1039/b211086e] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Increased UV-B through stratospheric ozone depletion leads to an increased chemical activity in the lower atmosphere (the troposphere). The effect of stratospheric ozone depletion on tropospheric ozone is small (though significant) compared to the ozone generated anthropogenically in areas already experiencing air pollution. Modeling and experimental studies suggest that the impacts of stratospheric ozone depletion on tropospheric ozone are different at different altitudes and for different chemical regimes. As a result the increase in ozone due to stratospheric ozone depletion may be greater in polluted regions. Attributable effects on concentrations are expected only in regions where local emissions make minor contributions. The vertical distribution of NOx (NO + NO2), the emission of volatile organic compounds and the abundance of water vapor, are important influencing factors. The long-term nature of stratospheric ozone depletion means that even a small increase in tropospheric ozone concentration can have a significant impact on human health and the environment. Trifluoroacetic acid (TFA) and chlorodifluoroacetic acid (CDFA) are produced by the atmospheric degradation of hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs). TFA has been measured in rain, rivers, lakes, and oceans, the ultimate sink for these and related compounds. Significant anthropogenic sources of TFA other than degradation HCFCs and HFCs have been identified. Toxicity tests under field conditions indicate that the concentrations of TFA and CDFA currently produced by the atmospheric degradation of HFCs and HCFCs do not present a risk to human health and the environment. The impact of the interaction between ozone depletion and future climate change is complex and a significant area of current research. For air quality and tropospheric composition, a range of physical parameters such as temperature, cloudiness and atmospheric transport will modify the impact of UV-B. Changes in the chemical composition of the atmosphere including aerosols will also have an impact. For example, tropospheric OH is the 'cleaning' agent of the troposphere. While increased UV-B increases the OH concentration, increases in concentration of gases like methane, carbon monoxide and volatile organic compounds will act as sinks for OH in troposphere and hence change air quality and chemical composition in the troposphere. Also, changes in the aerosol content of the atmosphere resulting from global climate change may affect ozone photolysis rate coefficients and hence reduce or increase tropospheric ozone concentrations.
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Affiliation(s)
- Keith R Solomon
- Centre for Toxicology, University of Guelph, Guelph, ON, N1G 2W1, Canada
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Zerefos CS. Photochemical Activity and Solar Ultraviolet Radiation (PAUR) Modulation Factors: An overview of the project. ACTA ACUST UNITED AC 2002. [DOI: 10.1029/2000jd000134] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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