Accuracy assessment of MODIS land aerosol optical thickness algorithms using AERONET measurements over North America

• Published in: Atmospheric Measurement Techniques
• Main Authors: H. Jethva, O. Torres, Y. Yoshida
• Format: Article in Journal/Newspaper
• Language: English
• Published: Copernicus Publications 2019
• Subjects: Environmental engineering; TA170-171; Earthwork. Foundations; TA715-787; Aerosol Robotic Network
• Online Access: https://doi.org/10.5194/amt-12-4291-2019; https://doaj.org/article/94bb9c66158f4e80842267ee3516a83b

The planned simultaneous availability of visible and near-IR observations from the geostationary platforms of Tropospheric Emissions: Monitoring of Pollution (TEMPO) and Geostationary Operational Environmental Satellites (GOES) 16/17 Advanced Base Imager (ABI) will present the opportunity of deriving an accurate aerosol product taking advantage of both ABI's high spatial resolution in the visible range and TEMPO's sensitivity to aerosol absorption in the near-UV range. Because the wavelengths of ABI are similar to those of the Moderate Resolution Imaging Spectroradiometer (MODIS), existing aerosol algorithms of MODIS can be applied to ABI observations. In this work, we evaluate three distinct aerosol algorithms of MODIS deriving aerosol optical thickness (AOT) over land surfaces using visible and near-IR observations. The Dark Target (DT), Deep Blue (DB), and Multiangle Implementation of Atmospheric Correction (MAIAC) algorithms are all applied to the radiance measurements of MODIS on board the Aqua satellite. We have evaluated each algorithm by comparing the satellite-retrieved AOT to space-time collocated ground-based sun photometer measurements of the same parameter at 171 sites of the Aerosol Robotic Network (AERONET) over North America (NA). A spatiotemporal scheme collocating the satellite retrievals with the ground-based measurements was applied consistently to all three retrieval datasets. We find that the statistical performance of all three algorithms is comparable over darker surfaces over eastern NA with the MAIAC algorithm providing relatively better comparison over western NA sites characterized by inhomogeneous elevation and bright surfaces. The higher spatial resolution of the MAIAC product (1 km) allows a substantially larger number of matchups than DB 10 km and DT 10 km (DT 3 km) products by 115 % and 120 % (86 %), respectively, over eastern NA and by 150 % and 220 % (197 %) over western NA. The characterization of the error in AOT for the three aerosol products as a function of bidirectional ...