A six year satellite-based assessment of the regional variations in aerosol indirect effects
Aerosols act as cloud condensation nuclei (CCN) for cloud water droplets, and changes in aerosol concentrations have significant microphysical impacts on the corresponding cloud properties. Moderate Resolution Imaging Spectroradiometer (MODIS) aerosol and cloud properties are combined with NCEP Rean...
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ftdoajarticles:oai:doaj.org/article:6feac5ce324d43468ea590e1fff9d741 2023-05-15T17:36:27+02:00 A six year satellite-based assessment of the regional variations in aerosol indirect effects T. A. Jones S. A. Christopher J. Quaas 2009-06-01T00:00:00Z https://doaj.org/article/6feac5ce324d43468ea590e1fff9d741 EN eng Copernicus Publications http://www.atmos-chem-phys.net/9/4091/2009/acp-9-4091-2009.pdf https://doaj.org/toc/1680-7316 https://doaj.org/toc/1680-7324 1680-7316 1680-7324 https://doaj.org/article/6feac5ce324d43468ea590e1fff9d741 Atmospheric Chemistry and Physics, Vol 9, Iss 12, Pp 4091-4114 (2009) Physics QC1-999 Chemistry QD1-999 article 2009 ftdoajarticles 2022-12-31T01:20:59Z Aerosols act as cloud condensation nuclei (CCN) for cloud water droplets, and changes in aerosol concentrations have significant microphysical impacts on the corresponding cloud properties. Moderate Resolution Imaging Spectroradiometer (MODIS) aerosol and cloud properties are combined with NCEP Reanalysis data for six different regions around the globe between March 2000 and December 2005 to study the effects of different aerosol, cloud, and atmospheric conditions on the aerosol indirect effect (AIE). Emphasis is placed in examining the relative importance of aerosol concentration, type, and atmospheric conditions (mainly vertical motion) to AIE from region to region. Results show that in most regions, AIE has a distinct seasonal cycle, though the cycle varies in significance and period from region to region. In the Arabian Sea (AS), the six-year mean anthropogenic + dust AIE is −0.27 Wm −2 and is greatest during the summer months (<−2.0 Wm −2 ) during which aerosol concentrations (from both dust and anthropogenic sources) are greatest. Comparing AIE as a function of thin (LWP<20 gm −2 ) vs. thick (LWP≥20 gm −2 ) clouds under conditions of large scale ascent or decent at 850 hPa showed that AIE is greatest for thick clouds during periods of upward vertical motion. In the Bay of Bengal, AIE is negligible owing to less favorable atmospheric conditions, a lower concentration of aerosols, and a non-alignment of aerosol and cloud layers. In the eastern North Atlantic, AIE is weakly positive (+0.1 Wm −2 ) with dust aerosol concentration being much greater than the anthropogenic or sea salt components. However, elevated dust in this region exists above the maritime cloud layers and does not have a hygroscopic coating, which occurs in AS, preventing the dust from acting as CCN and limiting AIE. The Western Atlantic has a large anthropogenic aerosol concentration transported from the eastern United States producing a modest anthropogenic AIE (−0.46 Wm −2 ). Anthropogenic AIE is also present off the West African ... Article in Journal/Newspaper North Atlantic Directory of Open Access Journals: DOAJ Articles |
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Physics QC1-999 Chemistry QD1-999 T. A. Jones S. A. Christopher J. Quaas A six year satellite-based assessment of the regional variations in aerosol indirect effects |
topic_facet |
Physics QC1-999 Chemistry QD1-999 |
description |
Aerosols act as cloud condensation nuclei (CCN) for cloud water droplets, and changes in aerosol concentrations have significant microphysical impacts on the corresponding cloud properties. Moderate Resolution Imaging Spectroradiometer (MODIS) aerosol and cloud properties are combined with NCEP Reanalysis data for six different regions around the globe between March 2000 and December 2005 to study the effects of different aerosol, cloud, and atmospheric conditions on the aerosol indirect effect (AIE). Emphasis is placed in examining the relative importance of aerosol concentration, type, and atmospheric conditions (mainly vertical motion) to AIE from region to region. Results show that in most regions, AIE has a distinct seasonal cycle, though the cycle varies in significance and period from region to region. In the Arabian Sea (AS), the six-year mean anthropogenic + dust AIE is −0.27 Wm −2 and is greatest during the summer months (<−2.0 Wm −2 ) during which aerosol concentrations (from both dust and anthropogenic sources) are greatest. Comparing AIE as a function of thin (LWP<20 gm −2 ) vs. thick (LWP≥20 gm −2 ) clouds under conditions of large scale ascent or decent at 850 hPa showed that AIE is greatest for thick clouds during periods of upward vertical motion. In the Bay of Bengal, AIE is negligible owing to less favorable atmospheric conditions, a lower concentration of aerosols, and a non-alignment of aerosol and cloud layers. In the eastern North Atlantic, AIE is weakly positive (+0.1 Wm −2 ) with dust aerosol concentration being much greater than the anthropogenic or sea salt components. However, elevated dust in this region exists above the maritime cloud layers and does not have a hygroscopic coating, which occurs in AS, preventing the dust from acting as CCN and limiting AIE. The Western Atlantic has a large anthropogenic aerosol concentration transported from the eastern United States producing a modest anthropogenic AIE (−0.46 Wm −2 ). Anthropogenic AIE is also present off the West African ... |
format |
Article in Journal/Newspaper |
author |
T. A. Jones S. A. Christopher J. Quaas |
author_facet |
T. A. Jones S. A. Christopher J. Quaas |
author_sort |
T. A. Jones |
title |
A six year satellite-based assessment of the regional variations in aerosol indirect effects |
title_short |
A six year satellite-based assessment of the regional variations in aerosol indirect effects |
title_full |
A six year satellite-based assessment of the regional variations in aerosol indirect effects |
title_fullStr |
A six year satellite-based assessment of the regional variations in aerosol indirect effects |
title_full_unstemmed |
A six year satellite-based assessment of the regional variations in aerosol indirect effects |
title_sort |
six year satellite-based assessment of the regional variations in aerosol indirect effects |
publisher |
Copernicus Publications |
publishDate |
2009 |
url |
https://doaj.org/article/6feac5ce324d43468ea590e1fff9d741 |
genre |
North Atlantic |
genre_facet |
North Atlantic |
op_source |
Atmospheric Chemistry and Physics, Vol 9, Iss 12, Pp 4091-4114 (2009) |
op_relation |
http://www.atmos-chem-phys.net/9/4091/2009/acp-9-4091-2009.pdf https://doaj.org/toc/1680-7316 https://doaj.org/toc/1680-7324 1680-7316 1680-7324 https://doaj.org/article/6feac5ce324d43468ea590e1fff9d741 |
_version_ |
1766135928653348864 |