Comparison of surface and column measurements of aerosol scattering properties over the western North Atlantic Ocean at Bermuda
Light scattering by size-resolved aerosols in near-surface air at Tudor Hill, Bermuda, was measured between January and June 2009. Vertical distributions of aerosol backscattering and column-averaged aerosol optical properties were characterized in parallel with a micro-pulse lidar (MPL) and an auto...
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ftnonlinearchiv:oai:noa.gwlb.de:cop_mods_00044895 2023-05-15T13:07:14+02:00 Comparison of surface and column measurements of aerosol scattering properties over the western North Atlantic Ocean at Bermuda Aryal, R. P. Voss, K. J. Terman, P. A. Keene, W. C. Moody, J. L. Welton, E. J. Holben, B. N. 2014-07 electronic https://doi.org/10.5194/acp-14-7617-2014 https://noa.gwlb.de/receive/cop_mods_00044895 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00044515/acp-14-7617-2014.pdf https://acp.copernicus.org/articles/14/7617/2014/acp-14-7617-2014.pdf eng eng Copernicus Publications Atmospheric Chemistry and Physics -- http://www.atmos-chem-phys.net/volumes_and_issues.html -- http://www.bibliothek.uni-regensburg.de/ezeit/?2069847 -- 1680-7324 https://doi.org/10.5194/acp-14-7617-2014 https://noa.gwlb.de/receive/cop_mods_00044895 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00044515/acp-14-7617-2014.pdf https://acp.copernicus.org/articles/14/7617/2014/acp-14-7617-2014.pdf uneingeschränkt info:eu-repo/semantics/openAccess article Verlagsveröffentlichung article Text doc-type:article 2014 ftnonlinearchiv https://doi.org/10.5194/acp-14-7617-2014 2022-02-08T22:39:51Z Light scattering by size-resolved aerosols in near-surface air at Tudor Hill, Bermuda, was measured between January and June 2009. Vertical distributions of aerosol backscattering and column-averaged aerosol optical properties were characterized in parallel with a micro-pulse lidar (MPL) and an automated sun–sky radiometer. Comparisons were made between extensive aerosol parameters in the column, such as the lidar-retrieved extinction at 400 m and the aerosol optical depth (AOD), and scattering was measured with a surface nephelometer. Comparisons were also made for intensive parameters such as the Ångström exponent and calculations using AERONET(Aerosol Robotic Network)-derived aerosol physical parameters (size distribution, index of refraction) and Mie theory, and the ratio of submicron scattering to total scattering for size-segregated nephelometer measurements. In these comparisons the r2 was generally around 0.50. Data were also evaluated based on back trajectories. The correlation between surface scattering and lidar extinction was highest for flows when the surface scattering was dominated by smaller particles and the flow had a longer footprint over land then over the ocean. The correlation of AOD with surface scatter was similar for all flow regimes. There was also no clear dependence of the atmospheric lapse rate, as determined from a nearby radiosonde station, on flow regime. The Ångström exponent for most flow regimes was 0.9–1.0, but for the case of air originating from North America, but with significant time over the ocean, the Ångström exponent was 0.57 ± 0.18. The submicron fraction of aerosol near the surface (Rsub-surf) was significantly greater for the flows from land (0.66 ± 0.11) than for the flows which spent more time over the ocean (0.40 ± 0.05). When comparing Rsub-surf and the column-integrated submicron scattering fraction, Rsub-col, the correlation was similar, r2 = 0.50, but Rsub-surf was generally less than Rsub-col, indicating more large particles contributing to light scattering at the surface, contrary to conditions over continents and for polluted continental transport over the ocean. In general, though, the marginal correlations indicate that the column optical properties are weakly correlated with the surface optical measurements. Thus, if it is desired to associate aerosol chemical/physical properties with their optical properties, it is best to use optical and chemical/physical measurements with both collected at the surface or both collected in the column. Article in Journal/Newspaper Aerosol Robotic Network North Atlantic Niedersächsisches Online-Archiv NOA Atmospheric Chemistry and Physics 14 14 7617 7629 |
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article Verlagsveröffentlichung Aryal, R. P. Voss, K. J. Terman, P. A. Keene, W. C. Moody, J. L. Welton, E. J. Holben, B. N. Comparison of surface and column measurements of aerosol scattering properties over the western North Atlantic Ocean at Bermuda |
topic_facet |
article Verlagsveröffentlichung |
description |
Light scattering by size-resolved aerosols in near-surface air at Tudor Hill, Bermuda, was measured between January and June 2009. Vertical distributions of aerosol backscattering and column-averaged aerosol optical properties were characterized in parallel with a micro-pulse lidar (MPL) and an automated sun–sky radiometer. Comparisons were made between extensive aerosol parameters in the column, such as the lidar-retrieved extinction at 400 m and the aerosol optical depth (AOD), and scattering was measured with a surface nephelometer. Comparisons were also made for intensive parameters such as the Ångström exponent and calculations using AERONET(Aerosol Robotic Network)-derived aerosol physical parameters (size distribution, index of refraction) and Mie theory, and the ratio of submicron scattering to total scattering for size-segregated nephelometer measurements. In these comparisons the r2 was generally around 0.50. Data were also evaluated based on back trajectories. The correlation between surface scattering and lidar extinction was highest for flows when the surface scattering was dominated by smaller particles and the flow had a longer footprint over land then over the ocean. The correlation of AOD with surface scatter was similar for all flow regimes. There was also no clear dependence of the atmospheric lapse rate, as determined from a nearby radiosonde station, on flow regime. The Ångström exponent for most flow regimes was 0.9–1.0, but for the case of air originating from North America, but with significant time over the ocean, the Ångström exponent was 0.57 ± 0.18. The submicron fraction of aerosol near the surface (Rsub-surf) was significantly greater for the flows from land (0.66 ± 0.11) than for the flows which spent more time over the ocean (0.40 ± 0.05). When comparing Rsub-surf and the column-integrated submicron scattering fraction, Rsub-col, the correlation was similar, r2 = 0.50, but Rsub-surf was generally less than Rsub-col, indicating more large particles contributing to light scattering at the surface, contrary to conditions over continents and for polluted continental transport over the ocean. In general, though, the marginal correlations indicate that the column optical properties are weakly correlated with the surface optical measurements. Thus, if it is desired to associate aerosol chemical/physical properties with their optical properties, it is best to use optical and chemical/physical measurements with both collected at the surface or both collected in the column. |
format |
Article in Journal/Newspaper |
author |
Aryal, R. P. Voss, K. J. Terman, P. A. Keene, W. C. Moody, J. L. Welton, E. J. Holben, B. N. |
author_facet |
Aryal, R. P. Voss, K. J. Terman, P. A. Keene, W. C. Moody, J. L. Welton, E. J. Holben, B. N. |
author_sort |
Aryal, R. P. |
title |
Comparison of surface and column measurements of aerosol scattering properties over the western North Atlantic Ocean at Bermuda |
title_short |
Comparison of surface and column measurements of aerosol scattering properties over the western North Atlantic Ocean at Bermuda |
title_full |
Comparison of surface and column measurements of aerosol scattering properties over the western North Atlantic Ocean at Bermuda |
title_fullStr |
Comparison of surface and column measurements of aerosol scattering properties over the western North Atlantic Ocean at Bermuda |
title_full_unstemmed |
Comparison of surface and column measurements of aerosol scattering properties over the western North Atlantic Ocean at Bermuda |
title_sort |
comparison of surface and column measurements of aerosol scattering properties over the western north atlantic ocean at bermuda |
publisher |
Copernicus Publications |
publishDate |
2014 |
url |
https://doi.org/10.5194/acp-14-7617-2014 https://noa.gwlb.de/receive/cop_mods_00044895 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00044515/acp-14-7617-2014.pdf https://acp.copernicus.org/articles/14/7617/2014/acp-14-7617-2014.pdf |
genre |
Aerosol Robotic Network North Atlantic |
genre_facet |
Aerosol Robotic Network North Atlantic |
op_relation |
Atmospheric Chemistry and Physics -- http://www.atmos-chem-phys.net/volumes_and_issues.html -- http://www.bibliothek.uni-regensburg.de/ezeit/?2069847 -- 1680-7324 https://doi.org/10.5194/acp-14-7617-2014 https://noa.gwlb.de/receive/cop_mods_00044895 https://noa.gwlb.de/servlets/MCRFileNodeServlet/cop_derivate_00044515/acp-14-7617-2014.pdf https://acp.copernicus.org/articles/14/7617/2014/acp-14-7617-2014.pdf |
op_rights |
uneingeschränkt info:eu-repo/semantics/openAccess |
op_doi |
https://doi.org/10.5194/acp-14-7617-2014 |
container_title |
Atmospheric Chemistry and Physics |
container_volume |
14 |
container_issue |
14 |
container_start_page |
7617 |
op_container_end_page |
7629 |
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1766041477402591232 |