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NASA NTRS · 20205007496

High-Resolution Gridded Level 3 Aerosol Optical Depth Data from MODIS

Pawan Gupta·Lorraine A Remer·Falguni Patadia·Robert C Levy·Sundar A Christopher
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Abstract

The state-of-art satellite observations of atmospheric aerosols over the last two decades from NASA's MODIS instruments have been extensively utilized in climate change and air quality research and applications. The operational algorithms now produce level 2 aerosol data at varying spatial resolutions (1, 3, and 10 km) and level 3 data at 1 degree. The local and global applications have been benefited from the coarse resolution gridded data sets (i.e., level 3, 1 degree), as it is easier to use since data volume is low and, several online and offline tools are readily available to access and analyze the data with minimal computing resources. At the same time, researchers who require data at much finer spatial scales have to go through a challenging process of obtaining, processing, and analyzing larger volumes of data sets that require high-end computing resources and coding skills. Therefore, we have created a high spatial resolution (HRG, 0.1x0.1 degree) daily and monthly aerosol optical depth (AOD) product by combining two MODIS operational algorithms, namely Deep Blue (DB) and Dark Target (DT). The new HRG AODs meets the accuracy requirements of level 2 AOD data and provide either the same or more spatial coverage on daily and monthly scales. The data sets are provided in daily and monthly files through open Ftp server with python scripts to read and map the data. The reduced data volume with an easy to use format and tools to access the data will encourage more users to utilize the data for research and applications.

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Pawan Gupta, Lorraine A Remer, Falguni Patadia, Robert C Levy, Sundar A Christopher. 2020-09-02. High-Resolution Gridded Level 3 Aerosol Optical Depth Data from MODIS. https://ntrs.nasa.gov/citations/20205007496

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