
Agricultural and Biosystems Engineering Publications
Campus Units
Agricultural and Biosystems Engineering
Document Type
Article
Publication Version
Published Version
Publication Date
7-27-2017
Journal or Book Title
Journal of Geophysical Research: Atmospheres
Volume
122
Issue
14
First Page
7537
Last Page
7559
DOI
10.1002/2016JD026301
Abstract
Moderate Resolution Imaging Spectroradiometer (MODIS) algorithm that combines time series approach and image processing to derive surface reflectance and atmosphere products, such as aerosol optical depth (AOD) and columnar water vapor (CWV). The quality assessment of MAIAC AOD at 1 km resolution is still lacking across South America. In the present study, critical assessment of MAIAC AOD550 was performed using ground‐truth data from 19 Aerosol Robotic Network (AERONET) sites over South America. Additionally, we validated the MAIAC CWV retrievals using the same AERONET sites. In general, MAIAC AOD Terra/Aqua retrievals show high agreement with ground‐based measurements, with a correlation coefficient (R) close to unity (RTerra:0.956 and RAqua: 0.949). MAIAC accuracy depends on the surface properties and comparisons revealed high confidence retrievals over cropland, forest, savanna, and grassland covers, where more than 2/3 (~66%) of retrievals are within the expected error (EE = ±(0.05 + 0.05 × AOD)) and R exceeding 0.86. However, AOD retrievals over bright surfaces show lower correlation than those over vegetated areas. Both MAIAC Terra and Aqua retrievals are similarly comparable to AERONET AOD over the MODIS lifetime (small bias offset ~0.006). Additionally, MAIAC CWV presents quantitative information with R ~ 0.97 and more than 70% of retrievals within error (±15%). Nonetheless, the time series validation shows an upward bias trend in CWV Terra retrievals and systematic negative bias for CWV Aqua. These results contribute to a comprehensive evaluation of MAIAC AOD retrievals as a new atmospheric product for future aerosol studies over South America.
Access
Open
Rights
Works produced by employees of the U.S. Government as part of their official duties are not copyrighted within the U.S. The content of this document is not copyrighted.
Language
en
File Format
application/pdf
Recommended Citation
Martins, Vitor S.; Lyapustin, Alexei; de Carvalho, Lino A.S.; Barbosa, Claudio C.F.; and Novo, Evlyn M.L.M., "Validation of high‐resolution MAIAC aerosol product over South America" (2017). Agricultural and Biosystems Engineering Publications. 1026.
https://lib.dr.iastate.edu/abe_eng_pubs/1026
Included in
Atmospheric Sciences Commons, Bioresource and Agricultural Engineering Commons, Environmental Monitoring Commons
Comments
This article is published as Martins, V. S., A. Lyapustin, L. A. S. de Carvalho, C. C. F. Barbosa, and E. M. L. M. Novo. "Validation of high‐resolution MAIAC aerosol product over South America." Journal of Geophysical Research: Atmospheres 122, no. 14 (2017): 7537-7559. DOI: 10.1002/2016JD026301.