Remote sensing of aerosol properties from multi-wavelength and multi-pixel information over the ocean
In this study, we investigate the feasibility of a multi-pixel scheme in the inversion of aerosol optical properties for multispectral satellite instruments over the ocean. Different from the traditional satellite aerosol retrievals conducted pixel by pixel, we derive the aerosol optical thickness (...
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ftcopernicus:oai:publications.copernicus.org:acp71714 2023-05-15T13:07:05+02:00 Remote sensing of aerosol properties from multi-wavelength and multi-pixel information over the ocean Shi, Chong Hashimoto, Makiko Nakajima, Teruyuki 2019-02-26 application/pdf https://doi.org/10.5194/acp-19-2461-2019 https://www.atmos-chem-phys.net/19/2461/2019/ eng eng doi:10.5194/acp-19-2461-2019 https://www.atmos-chem-phys.net/19/2461/2019/ eISSN: 1680-7324 Text 2019 ftcopernicus https://doi.org/10.5194/acp-19-2461-2019 2019-12-24T09:49:26Z In this study, we investigate the feasibility of a multi-pixel scheme in the inversion of aerosol optical properties for multispectral satellite instruments over the ocean. Different from the traditional satellite aerosol retrievals conducted pixel by pixel, we derive the aerosol optical thickness (AOT) of multiple pixels simultaneously by adding a smoothness constraint on the spatial variation of aerosols and oceanic substances, which helps the satellite retrieval, with higher consistency from pixel to pixel. Simulations are performed for two representative oceanic circumstances, open and coastal waters, as well as the land–ocean interface region. We retrieve the AOT for fine, sea spray, and dust aerosols simultaneously using synthetic spectral measurements, which are from the Greenhouse Gases Observing Satellite and Thermal and Near Infrared Sensor for Carbon Observation – Cloud and Aerosol Imager (GOSAT ∕ TANSO-CAI), with four wavelengths ranging from the ultraviolet to shortwave infrared bands. The forward radiation calculation is performed by a coupled atmosphere–ocean radiative transfer model combined with a three-component bio-optical oceanic module, where the chlorophyll a concentration, sediment, and colored dissolved organic matter are considered. Results show that accuracies of the derived AOT and spectral remote-sensing reflectance are both improved by applying smoothness constraints on the spatial variation of aerosol and oceanic substances in homogeneous or inhomogeneous surface conditions. The multi-pixel scheme can be effective in compensating for the retrieval biases induced by measurement errors and improving the retrieval sensitivity, particularly for the fine aerosols over the coastal water. We then apply the algorithm to derive AOTs using real satellite measurements. Results indicate that the multi-pixel method helps to polish the irregular retrieved results of the satellite imagery and is potentially promising for the aerosol retrieval over highly turbid waters by benefiting from the coincident retrieval of neighboring pixels. A comparison of retrieved AOTs from satellite measurements with those from the Aerosol Robotic Network (AERONET) also indicates that retrievals conducted by the multi-pixel scheme are more consistent with the AERONET observations. Text Aerosol Robotic Network Copernicus Publications: E-Journals Atmospheric Chemistry and Physics 19 4 2461 2475 |
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Open Polar |
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Copernicus Publications: E-Journals |
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ftcopernicus |
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English |
description |
In this study, we investigate the feasibility of a multi-pixel scheme in the inversion of aerosol optical properties for multispectral satellite instruments over the ocean. Different from the traditional satellite aerosol retrievals conducted pixel by pixel, we derive the aerosol optical thickness (AOT) of multiple pixels simultaneously by adding a smoothness constraint on the spatial variation of aerosols and oceanic substances, which helps the satellite retrieval, with higher consistency from pixel to pixel. Simulations are performed for two representative oceanic circumstances, open and coastal waters, as well as the land–ocean interface region. We retrieve the AOT for fine, sea spray, and dust aerosols simultaneously using synthetic spectral measurements, which are from the Greenhouse Gases Observing Satellite and Thermal and Near Infrared Sensor for Carbon Observation – Cloud and Aerosol Imager (GOSAT ∕ TANSO-CAI), with four wavelengths ranging from the ultraviolet to shortwave infrared bands. The forward radiation calculation is performed by a coupled atmosphere–ocean radiative transfer model combined with a three-component bio-optical oceanic module, where the chlorophyll a concentration, sediment, and colored dissolved organic matter are considered. Results show that accuracies of the derived AOT and spectral remote-sensing reflectance are both improved by applying smoothness constraints on the spatial variation of aerosol and oceanic substances in homogeneous or inhomogeneous surface conditions. The multi-pixel scheme can be effective in compensating for the retrieval biases induced by measurement errors and improving the retrieval sensitivity, particularly for the fine aerosols over the coastal water. We then apply the algorithm to derive AOTs using real satellite measurements. Results indicate that the multi-pixel method helps to polish the irregular retrieved results of the satellite imagery and is potentially promising for the aerosol retrieval over highly turbid waters by benefiting from the coincident retrieval of neighboring pixels. A comparison of retrieved AOTs from satellite measurements with those from the Aerosol Robotic Network (AERONET) also indicates that retrievals conducted by the multi-pixel scheme are more consistent with the AERONET observations. |
format |
Text |
author |
Shi, Chong Hashimoto, Makiko Nakajima, Teruyuki |
spellingShingle |
Shi, Chong Hashimoto, Makiko Nakajima, Teruyuki Remote sensing of aerosol properties from multi-wavelength and multi-pixel information over the ocean |
author_facet |
Shi, Chong Hashimoto, Makiko Nakajima, Teruyuki |
author_sort |
Shi, Chong |
title |
Remote sensing of aerosol properties from multi-wavelength and multi-pixel information over the ocean |
title_short |
Remote sensing of aerosol properties from multi-wavelength and multi-pixel information over the ocean |
title_full |
Remote sensing of aerosol properties from multi-wavelength and multi-pixel information over the ocean |
title_fullStr |
Remote sensing of aerosol properties from multi-wavelength and multi-pixel information over the ocean |
title_full_unstemmed |
Remote sensing of aerosol properties from multi-wavelength and multi-pixel information over the ocean |
title_sort |
remote sensing of aerosol properties from multi-wavelength and multi-pixel information over the ocean |
publishDate |
2019 |
url |
https://doi.org/10.5194/acp-19-2461-2019 https://www.atmos-chem-phys.net/19/2461/2019/ |
genre |
Aerosol Robotic Network |
genre_facet |
Aerosol Robotic Network |
op_source |
eISSN: 1680-7324 |
op_relation |
doi:10.5194/acp-19-2461-2019 https://www.atmos-chem-phys.net/19/2461/2019/ |
op_doi |
https://doi.org/10.5194/acp-19-2461-2019 |
container_title |
Atmospheric Chemistry and Physics |
container_volume |
19 |
container_issue |
4 |
container_start_page |
2461 |
op_container_end_page |
2475 |
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1766034145957380096 |