Aerosol decadal trends – Part 1: In-situ optical measurements at GAW and IMPROVE stations
Currently many ground-based atmospheric stations include in-situ measurements of aerosol physical and optical properties, resulting in more than 20 long-term (> 10 yr) aerosol measurement sites in the Northern Hemisphere and Antarctica. Most of these sites are located at remote locations and moni...
Published in: | Atmospheric Chemistry and Physics |
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2013
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Online Access: | https://doi.org/10.5194/acp-13-869-2013 https://doaj.org/article/b19c4ada0edb40a581d2bd8b8c6f5c72 |
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ftdoajarticles:oai:doaj.org/article:b19c4ada0edb40a581d2bd8b8c6f5c72 2023-05-15T14:01:58+02:00 Aerosol decadal trends – Part 1: In-situ optical measurements at GAW and IMPROVE stations M. Collaud Coen E. Andrews A. Asmi U. Baltensperger N. Bukowiecki D. Day M. Fiebig A. M. Fjaeraa H. Flentje A. Hyvärinen A. Jefferson S. G. Jennings G. Kouvarakis H. Lihavainen C. Lund Myhre W. C. Malm N. Mihapopoulos J. V. Molenar C. O'Dowd J. A. Ogren B. A. Schichtel P. Sheridan A. Virkkula E. Weingartner R. Weller P. Laj 2013-01-01T00:00:00Z https://doi.org/10.5194/acp-13-869-2013 https://doaj.org/article/b19c4ada0edb40a581d2bd8b8c6f5c72 EN eng Copernicus Publications http://www.atmos-chem-phys.net/13/869/2013/acp-13-869-2013.pdf https://doaj.org/toc/1680-7316 https://doaj.org/toc/1680-7324 doi:10.5194/acp-13-869-2013 1680-7316 1680-7324 https://doaj.org/article/b19c4ada0edb40a581d2bd8b8c6f5c72 Atmospheric Chemistry and Physics, Vol 13, Iss 2, Pp 869-894 (2013) Physics QC1-999 Chemistry QD1-999 article 2013 ftdoajarticles https://doi.org/10.5194/acp-13-869-2013 2022-12-31T09:58:28Z Currently many ground-based atmospheric stations include in-situ measurements of aerosol physical and optical properties, resulting in more than 20 long-term (> 10 yr) aerosol measurement sites in the Northern Hemisphere and Antarctica. Most of these sites are located at remote locations and monitor the aerosol particle number concentration, wavelength-dependent light scattering, backscattering, and absorption coefficients. The existence of these multi-year datasets enables the analysis of long-term trends of these aerosol parameters, and of the derived light scattering Ångström exponent and backscatter fraction. Since the aerosol variables are not normally distributed, three different methods (the seasonal Mann-Kendall test associated with the Sen's slope, the generalized least squares fit associated with an autoregressive bootstrap algorithm for confidence intervals, and the least-mean square fit applied to logarithms of the data) were applied to detect the long-term trends and their magnitudes. To allow a comparison among measurement sites, trends on the most recent 10 and 15 yr periods were calculated. No significant trends were found for the three continental European sites. Statistically significant trends were found for the two European marine sites but the signs of the trends varied with aerosol property and location. Statistically significant decreasing trends for both scattering and absorption coefficients (mean slope of −2.0% yr −1 ) were found for most North American stations, although positive trends were found for a few desert and high-altitude sites. The difference in the timing of emission reduction policy for the Europe and US continents is a likely explanation for the decreasing trends in aerosol optical parameters found for most American sites compared to the lack of trends observed in Europe. No significant trends in scattering coefficient were found for the Arctic or Antarctic stations, whereas the Arctic station had a negative trend in absorption coefficient. The high altitude Pacific ... Article in Journal/Newspaper Antarc* Antarctic Antarctica Arctic Directory of Open Access Journals: DOAJ Articles Antarctic Arctic Kendall ENVELOPE(-59.828,-59.828,-63.497,-63.497) Pacific Atmospheric Chemistry and Physics 13 2 869 894 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
Physics QC1-999 Chemistry QD1-999 |
spellingShingle |
Physics QC1-999 Chemistry QD1-999 M. Collaud Coen E. Andrews A. Asmi U. Baltensperger N. Bukowiecki D. Day M. Fiebig A. M. Fjaeraa H. Flentje A. Hyvärinen A. Jefferson S. G. Jennings G. Kouvarakis H. Lihavainen C. Lund Myhre W. C. Malm N. Mihapopoulos J. V. Molenar C. O'Dowd J. A. Ogren B. A. Schichtel P. Sheridan A. Virkkula E. Weingartner R. Weller P. Laj Aerosol decadal trends – Part 1: In-situ optical measurements at GAW and IMPROVE stations |
topic_facet |
Physics QC1-999 Chemistry QD1-999 |
description |
Currently many ground-based atmospheric stations include in-situ measurements of aerosol physical and optical properties, resulting in more than 20 long-term (> 10 yr) aerosol measurement sites in the Northern Hemisphere and Antarctica. Most of these sites are located at remote locations and monitor the aerosol particle number concentration, wavelength-dependent light scattering, backscattering, and absorption coefficients. The existence of these multi-year datasets enables the analysis of long-term trends of these aerosol parameters, and of the derived light scattering Ångström exponent and backscatter fraction. Since the aerosol variables are not normally distributed, three different methods (the seasonal Mann-Kendall test associated with the Sen's slope, the generalized least squares fit associated with an autoregressive bootstrap algorithm for confidence intervals, and the least-mean square fit applied to logarithms of the data) were applied to detect the long-term trends and their magnitudes. To allow a comparison among measurement sites, trends on the most recent 10 and 15 yr periods were calculated. No significant trends were found for the three continental European sites. Statistically significant trends were found for the two European marine sites but the signs of the trends varied with aerosol property and location. Statistically significant decreasing trends for both scattering and absorption coefficients (mean slope of −2.0% yr −1 ) were found for most North American stations, although positive trends were found for a few desert and high-altitude sites. The difference in the timing of emission reduction policy for the Europe and US continents is a likely explanation for the decreasing trends in aerosol optical parameters found for most American sites compared to the lack of trends observed in Europe. No significant trends in scattering coefficient were found for the Arctic or Antarctic stations, whereas the Arctic station had a negative trend in absorption coefficient. The high altitude Pacific ... |
format |
Article in Journal/Newspaper |
author |
M. Collaud Coen E. Andrews A. Asmi U. Baltensperger N. Bukowiecki D. Day M. Fiebig A. M. Fjaeraa H. Flentje A. Hyvärinen A. Jefferson S. G. Jennings G. Kouvarakis H. Lihavainen C. Lund Myhre W. C. Malm N. Mihapopoulos J. V. Molenar C. O'Dowd J. A. Ogren B. A. Schichtel P. Sheridan A. Virkkula E. Weingartner R. Weller P. Laj |
author_facet |
M. Collaud Coen E. Andrews A. Asmi U. Baltensperger N. Bukowiecki D. Day M. Fiebig A. M. Fjaeraa H. Flentje A. Hyvärinen A. Jefferson S. G. Jennings G. Kouvarakis H. Lihavainen C. Lund Myhre W. C. Malm N. Mihapopoulos J. V. Molenar C. O'Dowd J. A. Ogren B. A. Schichtel P. Sheridan A. Virkkula E. Weingartner R. Weller P. Laj |
author_sort |
M. Collaud Coen |
title |
Aerosol decadal trends – Part 1: In-situ optical measurements at GAW and IMPROVE stations |
title_short |
Aerosol decadal trends – Part 1: In-situ optical measurements at GAW and IMPROVE stations |
title_full |
Aerosol decadal trends – Part 1: In-situ optical measurements at GAW and IMPROVE stations |
title_fullStr |
Aerosol decadal trends – Part 1: In-situ optical measurements at GAW and IMPROVE stations |
title_full_unstemmed |
Aerosol decadal trends – Part 1: In-situ optical measurements at GAW and IMPROVE stations |
title_sort |
aerosol decadal trends – part 1: in-situ optical measurements at gaw and improve stations |
publisher |
Copernicus Publications |
publishDate |
2013 |
url |
https://doi.org/10.5194/acp-13-869-2013 https://doaj.org/article/b19c4ada0edb40a581d2bd8b8c6f5c72 |
long_lat |
ENVELOPE(-59.828,-59.828,-63.497,-63.497) |
geographic |
Antarctic Arctic Kendall Pacific |
geographic_facet |
Antarctic Arctic Kendall Pacific |
genre |
Antarc* Antarctic Antarctica Arctic |
genre_facet |
Antarc* Antarctic Antarctica Arctic |
op_source |
Atmospheric Chemistry and Physics, Vol 13, Iss 2, Pp 869-894 (2013) |
op_relation |
http://www.atmos-chem-phys.net/13/869/2013/acp-13-869-2013.pdf https://doaj.org/toc/1680-7316 https://doaj.org/toc/1680-7324 doi:10.5194/acp-13-869-2013 1680-7316 1680-7324 https://doaj.org/article/b19c4ada0edb40a581d2bd8b8c6f5c72 |
op_doi |
https://doi.org/10.5194/acp-13-869-2013 |
container_title |
Atmospheric Chemistry and Physics |
container_volume |
13 |
container_issue |
2 |
container_start_page |
869 |
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894 |
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1766272033193197568 |