Validation of MODIS 3 km Resolution Aerosol Optical Depth Retrievals Over Asia
This study evaluates the new Aqua MODIS Dark Target (DT) Collection 6 (C6) Aerosol Optical Depth (AOD) (MYD04_3K) retrieval algorithm at 3 km resolution over Asian countries that have recently experienced severe and increasing air pollution. Retrievals showed generally low accuracy compared with the...
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ftdoajarticles:oai:doaj.org/article:3a7d66ca3fb044dd85e2e25f32e65a04 2023-05-15T13:06:04+02:00 Validation of MODIS 3 km Resolution Aerosol Optical Depth Retrievals Over Asia Janet E. Nichol Muhammad Bilal 2016-04-01T00:00:00Z https://doi.org/10.3390/rs8040328 https://doaj.org/article/3a7d66ca3fb044dd85e2e25f32e65a04 EN eng MDPI AG http://www.mdpi.com/2072-4292/8/4/328 https://doaj.org/toc/2072-4292 2072-4292 doi:10.3390/rs8040328 https://doaj.org/article/3a7d66ca3fb044dd85e2e25f32e65a04 Remote Sensing, Vol 8, Iss 4, p 328 (2016) AERONET MODIS 3 km AOD Asia Science Q article 2016 ftdoajarticles https://doi.org/10.3390/rs8040328 2022-12-31T15:17:02Z This study evaluates the new Aqua MODIS Dark Target (DT) Collection 6 (C6) Aerosol Optical Depth (AOD) (MYD04_3K) retrieval algorithm at 3 km resolution over Asian countries that have recently experienced severe and increasing air pollution. Retrievals showed generally low accuracy compared with the AErosol RObotic NETwork (AERONET), with only 55% of retrievals within the expected error (EE). The uncertainty appears mainly due to systematic overestimation at both low and high AOD levels. This is attributed to under-prediction of surface reflectance, similar to, but more severe than, the C6 DT product at 10-km resolution. This is because MYD04_3K observes more noise in the surface reflectance computations, due to retention of some bright pixels in the retrieval window which would be discarded at 10 km. Greatest uncertainty was observed at urban sites, especially those dominated by coarse aerosols. Results suggest that the DT at 3 km is less reliable than MODIS C6 AOD products at 10 km. Article in Journal/Newspaper Aerosol Robotic Network Directory of Open Access Journals: DOAJ Articles Remote Sensing 8 4 328 |
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Open Polar |
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Directory of Open Access Journals: DOAJ Articles |
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ftdoajarticles |
language |
English |
topic |
AERONET MODIS 3 km AOD Asia Science Q |
spellingShingle |
AERONET MODIS 3 km AOD Asia Science Q Janet E. Nichol Muhammad Bilal Validation of MODIS 3 km Resolution Aerosol Optical Depth Retrievals Over Asia |
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AERONET MODIS 3 km AOD Asia Science Q |
description |
This study evaluates the new Aqua MODIS Dark Target (DT) Collection 6 (C6) Aerosol Optical Depth (AOD) (MYD04_3K) retrieval algorithm at 3 km resolution over Asian countries that have recently experienced severe and increasing air pollution. Retrievals showed generally low accuracy compared with the AErosol RObotic NETwork (AERONET), with only 55% of retrievals within the expected error (EE). The uncertainty appears mainly due to systematic overestimation at both low and high AOD levels. This is attributed to under-prediction of surface reflectance, similar to, but more severe than, the C6 DT product at 10-km resolution. This is because MYD04_3K observes more noise in the surface reflectance computations, due to retention of some bright pixels in the retrieval window which would be discarded at 10 km. Greatest uncertainty was observed at urban sites, especially those dominated by coarse aerosols. Results suggest that the DT at 3 km is less reliable than MODIS C6 AOD products at 10 km. |
format |
Article in Journal/Newspaper |
author |
Janet E. Nichol Muhammad Bilal |
author_facet |
Janet E. Nichol Muhammad Bilal |
author_sort |
Janet E. Nichol |
title |
Validation of MODIS 3 km Resolution Aerosol Optical Depth Retrievals Over Asia |
title_short |
Validation of MODIS 3 km Resolution Aerosol Optical Depth Retrievals Over Asia |
title_full |
Validation of MODIS 3 km Resolution Aerosol Optical Depth Retrievals Over Asia |
title_fullStr |
Validation of MODIS 3 km Resolution Aerosol Optical Depth Retrievals Over Asia |
title_full_unstemmed |
Validation of MODIS 3 km Resolution Aerosol Optical Depth Retrievals Over Asia |
title_sort |
validation of modis 3 km resolution aerosol optical depth retrievals over asia |
publisher |
MDPI AG |
publishDate |
2016 |
url |
https://doi.org/10.3390/rs8040328 https://doaj.org/article/3a7d66ca3fb044dd85e2e25f32e65a04 |
genre |
Aerosol Robotic Network |
genre_facet |
Aerosol Robotic Network |
op_source |
Remote Sensing, Vol 8, Iss 4, p 328 (2016) |
op_relation |
http://www.mdpi.com/2072-4292/8/4/328 https://doaj.org/toc/2072-4292 2072-4292 doi:10.3390/rs8040328 https://doaj.org/article/3a7d66ca3fb044dd85e2e25f32e65a04 |
op_doi |
https://doi.org/10.3390/rs8040328 |
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Remote Sensing |
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8 |
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4 |
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328 |
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1766402428635185152 |