Characterization of aerosol size properties from measurements of spectral optical depth: a global validation of the GRASP-AOD code using long-term AERONET data
A validation study is conducted regarding aerosol optical size property retrievals from measurements of the direct sun beam only (without the aid of diffuse radiation). The study focuses on using real data to test the new GRASP-AOD application, which uses only spectral optical depth measurements to...
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ftdoajarticles:oai:doaj.org/article:ef8d4dff99f74cecb8a093f94f55ab70 2023-05-15T13:07:05+02:00 Characterization of aerosol size properties from measurements of spectral optical depth: a global validation of the GRASP-AOD code using long-term AERONET data B. Torres D. Fuertes 2021-06-01T00:00:00Z https://doi.org/10.5194/amt-14-4471-2021 https://doaj.org/article/ef8d4dff99f74cecb8a093f94f55ab70 EN eng Copernicus Publications https://amt.copernicus.org/articles/14/4471/2021/amt-14-4471-2021.pdf https://doaj.org/toc/1867-1381 https://doaj.org/toc/1867-8548 doi:10.5194/amt-14-4471-2021 1867-1381 1867-8548 https://doaj.org/article/ef8d4dff99f74cecb8a093f94f55ab70 Atmospheric Measurement Techniques, Vol 14, Pp 4471-4506 (2021) Environmental engineering TA170-171 Earthwork. Foundations TA715-787 article 2021 ftdoajarticles https://doi.org/10.5194/amt-14-4471-2021 2022-12-31T11:58:40Z A validation study is conducted regarding aerosol optical size property retrievals from measurements of the direct sun beam only (without the aid of diffuse radiation). The study focuses on using real data to test the new GRASP-AOD application, which uses only spectral optical depth measurements to retrieve the total column aerosol size distributions, assumed to be bimodal lognormal. In addition, a set of secondary integral parameters of aerosol size distribution and optical properties are provided: effective radius, total volume concentration and fine-mode fraction of aerosol optical depth (AOD). The GRASP-AOD code is applied to almost 3 million observations acquired over 20 years (1997–2016) at 30 AERONET (Aerosol Robotic Network) sites. These validation sites have been selected based on known availability of an extensive data record, significant aerosol load variability throughout the year, wide worldwide coverage and diverse aerosol types and source regions. The output parameters are compared to those coming from the operational AERONET retrievals. The retrieved fine-mode fractions at 500 nm ( τ f (500) ) obtained by the GRASP-AOD application are compared to those retrieved by the spectral deconvolution algorithm (SDA) and by the AERONET aerosol retrieval algorithm. The size distribution properties obtained by the GRASP-AOD are compared to their equivalent values from the AERONET aerosol retrieval algorithm. The analysis showed the convincing capacity of the GRASP-AOD approach to successfully discriminate between fine- and coarse-mode extinction to robustly retrieve τ f (500) . The comparisons of 2 million results of τ f (500) retrieval by the GRASP-AOD and SDA showed high correlation with a root mean square error (RMSE) of 0.015 . Also, the analysis showed that the τ f (500) values computed by the AERONET aerosol retrieval algorithm agree slightly better with the GRASP-AOD (RMSE = 0.018, from 148 526 comparisons) than with the SDA (RMSE = 0.022, from 127 203 comparisons). The comparisons of the size ... Article in Journal/Newspaper Aerosol Robotic Network Directory of Open Access Journals: DOAJ Articles Atmospheric Measurement Techniques 14 6 4471 4506 |
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Directory of Open Access Journals: DOAJ Articles |
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ftdoajarticles |
language |
English |
topic |
Environmental engineering TA170-171 Earthwork. Foundations TA715-787 |
spellingShingle |
Environmental engineering TA170-171 Earthwork. Foundations TA715-787 B. Torres D. Fuertes Characterization of aerosol size properties from measurements of spectral optical depth: a global validation of the GRASP-AOD code using long-term AERONET data |
topic_facet |
Environmental engineering TA170-171 Earthwork. Foundations TA715-787 |
description |
A validation study is conducted regarding aerosol optical size property retrievals from measurements of the direct sun beam only (without the aid of diffuse radiation). The study focuses on using real data to test the new GRASP-AOD application, which uses only spectral optical depth measurements to retrieve the total column aerosol size distributions, assumed to be bimodal lognormal. In addition, a set of secondary integral parameters of aerosol size distribution and optical properties are provided: effective radius, total volume concentration and fine-mode fraction of aerosol optical depth (AOD). The GRASP-AOD code is applied to almost 3 million observations acquired over 20 years (1997–2016) at 30 AERONET (Aerosol Robotic Network) sites. These validation sites have been selected based on known availability of an extensive data record, significant aerosol load variability throughout the year, wide worldwide coverage and diverse aerosol types and source regions. The output parameters are compared to those coming from the operational AERONET retrievals. The retrieved fine-mode fractions at 500 nm ( τ f (500) ) obtained by the GRASP-AOD application are compared to those retrieved by the spectral deconvolution algorithm (SDA) and by the AERONET aerosol retrieval algorithm. The size distribution properties obtained by the GRASP-AOD are compared to their equivalent values from the AERONET aerosol retrieval algorithm. The analysis showed the convincing capacity of the GRASP-AOD approach to successfully discriminate between fine- and coarse-mode extinction to robustly retrieve τ f (500) . The comparisons of 2 million results of τ f (500) retrieval by the GRASP-AOD and SDA showed high correlation with a root mean square error (RMSE) of 0.015 . Also, the analysis showed that the τ f (500) values computed by the AERONET aerosol retrieval algorithm agree slightly better with the GRASP-AOD (RMSE = 0.018, from 148 526 comparisons) than with the SDA (RMSE = 0.022, from 127 203 comparisons). The comparisons of the size ... |
format |
Article in Journal/Newspaper |
author |
B. Torres D. Fuertes |
author_facet |
B. Torres D. Fuertes |
author_sort |
B. Torres |
title |
Characterization of aerosol size properties from measurements of spectral optical depth: a global validation of the GRASP-AOD code using long-term AERONET data |
title_short |
Characterization of aerosol size properties from measurements of spectral optical depth: a global validation of the GRASP-AOD code using long-term AERONET data |
title_full |
Characterization of aerosol size properties from measurements of spectral optical depth: a global validation of the GRASP-AOD code using long-term AERONET data |
title_fullStr |
Characterization of aerosol size properties from measurements of spectral optical depth: a global validation of the GRASP-AOD code using long-term AERONET data |
title_full_unstemmed |
Characterization of aerosol size properties from measurements of spectral optical depth: a global validation of the GRASP-AOD code using long-term AERONET data |
title_sort |
characterization of aerosol size properties from measurements of spectral optical depth: a global validation of the grasp-aod code using long-term aeronet data |
publisher |
Copernicus Publications |
publishDate |
2021 |
url |
https://doi.org/10.5194/amt-14-4471-2021 https://doaj.org/article/ef8d4dff99f74cecb8a093f94f55ab70 |
genre |
Aerosol Robotic Network |
genre_facet |
Aerosol Robotic Network |
op_source |
Atmospheric Measurement Techniques, Vol 14, Pp 4471-4506 (2021) |
op_relation |
https://amt.copernicus.org/articles/14/4471/2021/amt-14-4471-2021.pdf https://doaj.org/toc/1867-1381 https://doaj.org/toc/1867-8548 doi:10.5194/amt-14-4471-2021 1867-1381 1867-8548 https://doaj.org/article/ef8d4dff99f74cecb8a093f94f55ab70 |
op_doi |
https://doi.org/10.5194/amt-14-4471-2021 |
container_title |
Atmospheric Measurement Techniques |
container_volume |
14 |
container_issue |
6 |
container_start_page |
4471 |
op_container_end_page |
4506 |
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1766034373492080640 |