Aerosol remote sensing in polar regions
Multi-year sets of ground-based sun-photometer measurements conducted at 12 Arctic sites and 9 Antarctic sites were examined to determine daily mean values of aerosol optical thickness τ(λ) at visible and near-infrared wavelengths, from which best-fit values of Ångström's exponent α were calcul...
Published in: | Earth-Science Reviews |
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Main Authors: | , , , , |
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Format: | Article in Journal/Newspaper |
Language: | English |
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Elsevier
2015
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Subjects: | |
Online Access: | http://hdl.handle.net/10394/18835 https://doi.org/10.1016/j.earscirev.2014.11.001 http://www.sciencedirect.com/science/article/pii/S0012825214001913 |
id |
ftnorthwestuniv:oai:dspace.nwu.ac.za:10394/18835 |
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record_format |
openpolar |
institution |
Open Polar |
collection |
North-West University, South Africa: Boloka (NWU-IR) |
op_collection_id |
ftnorthwestuniv |
language |
English |
topic |
Sun-photometer measurements aerosol optical thickness polar aerosol optical characteristics lidar backscattering coefficient profiles satellite aerosol remote sensing multimodal aerosol extinction models |
spellingShingle |
Sun-photometer measurements aerosol optical thickness polar aerosol optical characteristics lidar backscattering coefficient profiles satellite aerosol remote sensing multimodal aerosol extinction models Tomasi, Claudio Piketh, Stuart J. Kokhanovsky, Alexander A. Lupi, Angelo Ritter, Christoph Aerosol remote sensing in polar regions |
topic_facet |
Sun-photometer measurements aerosol optical thickness polar aerosol optical characteristics lidar backscattering coefficient profiles satellite aerosol remote sensing multimodal aerosol extinction models |
description |
Multi-year sets of ground-based sun-photometer measurements conducted at 12 Arctic sites and 9 Antarctic sites were examined to determine daily mean values of aerosol optical thickness τ(λ) at visible and near-infrared wavelengths, from which best-fit values of Ångström's exponent α were calculated. Analysing these data, the monthly mean values of τ(0.50 μm) and α and the relative frequency histograms of the daily mean values of both parameters were determined for winter–spring and summer–autumn in the Arctic and for austral summer in Antarctica. The Arctic and Antarctic covariance plots of the seasonal median values of α versus τ(0.50 μm) showed: (i) a considerable increase in τ(0.50 μm) for the Arctic aerosol from summer to winter–spring, without marked changes in α; and (ii) a marked increase in τ(0.50 μm) passing from the Antarctic Plateau to coastal sites, whereas α decreased considerably due to the larger fraction of sea-salt aerosol. Good agreement was found when comparing ground-based sun-photometer measurements of τ(λ) and α at Arctic and Antarctic coastal sites with Microtops measurements conducted during numerous AERONET/MAN cruises from 2006 to 2013 in three Arctic Ocean sectors and in coastal and off-shore regions of the Southern Atlantic, Pacific, and Indian Oceans, and the Antarctic Peninsula. Lidar measurements were also examined to characterise vertical profiles of the aerosol backscattering coefficient measured throughout the year at Ny-Ålesund. Satellite-based MODIS, MISR, and AATSR retrievals of τ(λ) over large parts of the oceanic polar regions during spring and summer were in close agreement with ship-borne and coastal ground-based sun-photometer measurements. An overview of the chemical composition of mode particles is also presented, based on in-situ measurements at Arctic and Antarctic sites. Fourteen log-normal aerosol number size-distributions were defined to represent the average features of nuclei, accumulation and coarse mode particles for Arctic haze, summer background aerosol, Asian dust and boreal forest fire smoke, and for various background austral summer aerosol types at coastal and high-altitude Antarctic sites. The main columnar aerosol optical characteristics were determined for all 14 particle modes, based on in-situ measurements of the scattering and absorption coefficients. Diurnally averaged direct aerosol-induced radiative forcing and efficiency were calculated for a set of multimodal aerosol extinction models, using various Bidirectional Reflectance Distribution Function models over vegetation-covered, oceanic and snow-covered surfaces. These gave a reliable measure of the pronounced effects of aerosols on the radiation balance of the surface–atmosphere system over polar regions |
author2 |
18002080 - Piketh, Stuart John |
format |
Article in Journal/Newspaper |
author |
Tomasi, Claudio Piketh, Stuart J. Kokhanovsky, Alexander A. Lupi, Angelo Ritter, Christoph |
author_facet |
Tomasi, Claudio Piketh, Stuart J. Kokhanovsky, Alexander A. Lupi, Angelo Ritter, Christoph |
author_sort |
Tomasi, Claudio |
title |
Aerosol remote sensing in polar regions |
title_short |
Aerosol remote sensing in polar regions |
title_full |
Aerosol remote sensing in polar regions |
title_fullStr |
Aerosol remote sensing in polar regions |
title_full_unstemmed |
Aerosol remote sensing in polar regions |
title_sort |
aerosol remote sensing in polar regions |
publisher |
Elsevier |
publishDate |
2015 |
url |
http://hdl.handle.net/10394/18835 https://doi.org/10.1016/j.earscirev.2014.11.001 http://www.sciencedirect.com/science/article/pii/S0012825214001913 |
geographic |
Antarctic Antarctic Peninsula Arctic Arctic Ocean Austral Indian Ny-Ålesund Pacific The Antarctic |
geographic_facet |
Antarctic Antarctic Peninsula Arctic Arctic Ocean Austral Indian Ny-Ålesund Pacific The Antarctic |
genre |
Antarc* Antarctic Antarctic Peninsula Antarctica Arctic Arctic Ocean Ny Ålesund Ny-Ålesund |
genre_facet |
Antarc* Antarctic Antarctic Peninsula Antarctica Arctic Arctic Ocean Ny Ålesund Ny-Ålesund |
op_relation |
Tomasi, C. et al. 2015. Aerosol remote sensing in polar regions. Earth-science reviews, 140:108–157. [http://www.journals.elsevier.com/earth-science-reviews/] 0012–8252 1872–6828 (Online) http://hdl.handle.net/10394/18835 http://dx.doi.org/10.1016/j.earscirev.2014.11.001 http://www.sciencedirect.com/science/article/pii/S0012825214001913 |
op_doi |
https://doi.org/10.1016/j.earscirev.2014.11.001 |
container_title |
Earth-Science Reviews |
container_volume |
140 |
container_start_page |
108 |
op_container_end_page |
157 |
_version_ |
1766204333675773952 |
spelling |
ftnorthwestuniv:oai:dspace.nwu.ac.za:10394/18835 2023-05-15T13:44:38+02:00 Aerosol remote sensing in polar regions Tomasi, Claudio Piketh, Stuart J. Kokhanovsky, Alexander A. Lupi, Angelo Ritter, Christoph 18002080 - Piketh, Stuart John 2015 http://hdl.handle.net/10394/18835 https://doi.org/10.1016/j.earscirev.2014.11.001 http://www.sciencedirect.com/science/article/pii/S0012825214001913 en eng Elsevier Tomasi, C. et al. 2015. Aerosol remote sensing in polar regions. Earth-science reviews, 140:108–157. [http://www.journals.elsevier.com/earth-science-reviews/] 0012–8252 1872–6828 (Online) http://hdl.handle.net/10394/18835 http://dx.doi.org/10.1016/j.earscirev.2014.11.001 http://www.sciencedirect.com/science/article/pii/S0012825214001913 Sun-photometer measurements aerosol optical thickness polar aerosol optical characteristics lidar backscattering coefficient profiles satellite aerosol remote sensing multimodal aerosol extinction models Article 2015 ftnorthwestuniv https://doi.org/10.1016/j.earscirev.2014.11.001 2019-06-04T13:13:04Z Multi-year sets of ground-based sun-photometer measurements conducted at 12 Arctic sites and 9 Antarctic sites were examined to determine daily mean values of aerosol optical thickness τ(λ) at visible and near-infrared wavelengths, from which best-fit values of Ångström's exponent α were calculated. Analysing these data, the monthly mean values of τ(0.50 μm) and α and the relative frequency histograms of the daily mean values of both parameters were determined for winter–spring and summer–autumn in the Arctic and for austral summer in Antarctica. The Arctic and Antarctic covariance plots of the seasonal median values of α versus τ(0.50 μm) showed: (i) a considerable increase in τ(0.50 μm) for the Arctic aerosol from summer to winter–spring, without marked changes in α; and (ii) a marked increase in τ(0.50 μm) passing from the Antarctic Plateau to coastal sites, whereas α decreased considerably due to the larger fraction of sea-salt aerosol. Good agreement was found when comparing ground-based sun-photometer measurements of τ(λ) and α at Arctic and Antarctic coastal sites with Microtops measurements conducted during numerous AERONET/MAN cruises from 2006 to 2013 in three Arctic Ocean sectors and in coastal and off-shore regions of the Southern Atlantic, Pacific, and Indian Oceans, and the Antarctic Peninsula. Lidar measurements were also examined to characterise vertical profiles of the aerosol backscattering coefficient measured throughout the year at Ny-Ålesund. Satellite-based MODIS, MISR, and AATSR retrievals of τ(λ) over large parts of the oceanic polar regions during spring and summer were in close agreement with ship-borne and coastal ground-based sun-photometer measurements. An overview of the chemical composition of mode particles is also presented, based on in-situ measurements at Arctic and Antarctic sites. Fourteen log-normal aerosol number size-distributions were defined to represent the average features of nuclei, accumulation and coarse mode particles for Arctic haze, summer background aerosol, Asian dust and boreal forest fire smoke, and for various background austral summer aerosol types at coastal and high-altitude Antarctic sites. The main columnar aerosol optical characteristics were determined for all 14 particle modes, based on in-situ measurements of the scattering and absorption coefficients. Diurnally averaged direct aerosol-induced radiative forcing and efficiency were calculated for a set of multimodal aerosol extinction models, using various Bidirectional Reflectance Distribution Function models over vegetation-covered, oceanic and snow-covered surfaces. These gave a reliable measure of the pronounced effects of aerosols on the radiation balance of the surface–atmosphere system over polar regions Article in Journal/Newspaper Antarc* Antarctic Antarctic Peninsula Antarctica Arctic Arctic Ocean Ny Ålesund Ny-Ålesund North-West University, South Africa: Boloka (NWU-IR) Antarctic Antarctic Peninsula Arctic Arctic Ocean Austral Indian Ny-Ålesund Pacific The Antarctic Earth-Science Reviews 140 108 157 |