A Method to Estimate Aerosol Radiative Forcing from Spectral Optical Depths
Radiative forcing of aerosols is much more difficult to estimate than that of well-mixed gases due to the large spatial variability of aerosols and the lack of an adequate database on their radiative properties. Estimation of aerosol radiative forcing generally requires knowledge of its chemical com...
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ftiiscindia:oai:eprints.iisc.ernet.in:7255 2023-05-15T13:06:44+02:00 A Method to Estimate Aerosol Radiative Forcing from Spectral Optical Depths Satheesh, SK Srinivasan, J 2006-03 application/pdf http://eprints.iisc.ernet.in/7255/ http://eprints.iisc.ernet.in/7255/1/A_method_to_estimate_aerosol_radiative_forcing_from_spectral_optical_depths.pdf unknown American Meteorological Society http://eprints.iisc.ernet.in/7255/1/A_method_to_estimate_aerosol_radiative_forcing_from_spectral_optical_depths.pdf Satheesh, SK and Srinivasan, J (2006) A Method to Estimate Aerosol Radiative Forcing from Spectral Optical Depths. In: Journal of the Atmospheric Sciences, 63 (3). pp. 1082-1092. Centre for Atmospheric & Oceanic Sciences Journal Article PeerReviewed 2006 ftiiscindia 2014-09-27T17:07:37Z Radiative forcing of aerosols is much more difficult to estimate than that of well-mixed gases due to the large spatial variability of aerosols and the lack of an adequate database on their radiative properties. Estimation of aerosol radiative forcing generally requires knowledge of its chemical composition, which is sparse. Ground-based sky radiance measurements [e.g., aerosol robotic network (AERONET)] can provide key parameters such as the single-scattering albedo, but in shipborne experiments over the ocean it is difficult to make sky radiance measurements and hence these experiments cannot provide parameters such as the single-scattering albedo. However, aerosol spectral optical depth data (cruise based as well as satellite retrieved) are available quite extensively over the ocean. Spectral optical depth measurements have been available since the 1970s, and spectral turbidity measurements (carried out at meteorological departments all over the world) have been available for several decades, while long-term continuous chemical composition information is not available. A new method to differentiate between scattering and absorbing aerosols is proposed here. This can be used to derive simple aerosol models that are optically equivalent and can simulate the observed aerosol optical properties and radiative fluxes, from spectral optical depth measurements. Thus, aerosol single-scattering albedo and, hence, aerosol radiative forcing can be estimated. Note that the proposed method is to estimate clear-sky aerosol radiative forcing (over regions where chemical composition data or sky radiance data are not available) and not to infer its exact chemical composition. Using several independent datasets from field experiments, it is demonstrated that the proposed method can be used to estimate aerosol radiative forcing (from spectral optical depths) with an accuracy of $\pm2 W m^{_-2}$. Article in Journal/Newspaper Aerosol Robotic Network Indian Institute of Science, Bangalore: ePrints@IIsc |
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Indian Institute of Science, Bangalore: ePrints@IIsc |
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Centre for Atmospheric & Oceanic Sciences |
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Centre for Atmospheric & Oceanic Sciences Satheesh, SK Srinivasan, J A Method to Estimate Aerosol Radiative Forcing from Spectral Optical Depths |
topic_facet |
Centre for Atmospheric & Oceanic Sciences |
description |
Radiative forcing of aerosols is much more difficult to estimate than that of well-mixed gases due to the large spatial variability of aerosols and the lack of an adequate database on their radiative properties. Estimation of aerosol radiative forcing generally requires knowledge of its chemical composition, which is sparse. Ground-based sky radiance measurements [e.g., aerosol robotic network (AERONET)] can provide key parameters such as the single-scattering albedo, but in shipborne experiments over the ocean it is difficult to make sky radiance measurements and hence these experiments cannot provide parameters such as the single-scattering albedo. However, aerosol spectral optical depth data (cruise based as well as satellite retrieved) are available quite extensively over the ocean. Spectral optical depth measurements have been available since the 1970s, and spectral turbidity measurements (carried out at meteorological departments all over the world) have been available for several decades, while long-term continuous chemical composition information is not available. A new method to differentiate between scattering and absorbing aerosols is proposed here. This can be used to derive simple aerosol models that are optically equivalent and can simulate the observed aerosol optical properties and radiative fluxes, from spectral optical depth measurements. Thus, aerosol single-scattering albedo and, hence, aerosol radiative forcing can be estimated. Note that the proposed method is to estimate clear-sky aerosol radiative forcing (over regions where chemical composition data or sky radiance data are not available) and not to infer its exact chemical composition. Using several independent datasets from field experiments, it is demonstrated that the proposed method can be used to estimate aerosol radiative forcing (from spectral optical depths) with an accuracy of $\pm2 W m^{_-2}$. |
format |
Article in Journal/Newspaper |
author |
Satheesh, SK Srinivasan, J |
author_facet |
Satheesh, SK Srinivasan, J |
author_sort |
Satheesh, SK |
title |
A Method to Estimate Aerosol Radiative Forcing from Spectral Optical Depths |
title_short |
A Method to Estimate Aerosol Radiative Forcing from Spectral Optical Depths |
title_full |
A Method to Estimate Aerosol Radiative Forcing from Spectral Optical Depths |
title_fullStr |
A Method to Estimate Aerosol Radiative Forcing from Spectral Optical Depths |
title_full_unstemmed |
A Method to Estimate Aerosol Radiative Forcing from Spectral Optical Depths |
title_sort |
method to estimate aerosol radiative forcing from spectral optical depths |
publisher |
American Meteorological Society |
publishDate |
2006 |
url |
http://eprints.iisc.ernet.in/7255/ http://eprints.iisc.ernet.in/7255/1/A_method_to_estimate_aerosol_radiative_forcing_from_spectral_optical_depths.pdf |
genre |
Aerosol Robotic Network |
genre_facet |
Aerosol Robotic Network |
op_relation |
http://eprints.iisc.ernet.in/7255/1/A_method_to_estimate_aerosol_radiative_forcing_from_spectral_optical_depths.pdf Satheesh, SK and Srinivasan, J (2006) A Method to Estimate Aerosol Radiative Forcing from Spectral Optical Depths. In: Journal of the Atmospheric Sciences, 63 (3). pp. 1082-1092. |
_version_ |
1766018689222574080 |