Publications

Okpalaonwuka, C; Olusegun, CF; Olusola, A; Ogunjo, S (2023). Validation of MODIS AOD retrievals in West Africa: a comparison with AERONET observations. AIR QUALITY ATMOSPHERE AND HEALTH, 16(10), 2085-2094.

Abstract
There is increasing use of satellite data for environmental monitoring in data-sparse regions of the world. However, challenges such as cloud cover and swath area of satellite sensors necessitate the validation of satellite retrievals, particularly in regions where ground-based measurements or high-density coverage may be sparse. In this study, the performance of two NASA MODIS products-AQUA and TERRA-were compared with observational AERONET data over eight study sites in West Africa for the period 2000-2022. Results obtained showed a regression slope between 0.09 and 0.83 for TERRA data and 0.11 and 0.86 for AQUA data. The normalized root mean square error between AERONET and AQUA data was in the range of 0.097-0.517, while a range of 0.123-0.540 was reported for TERRA data. Although both AQUA and TERRA AOD products had similar aerosol trends across the eight AERONET study sites, AQUA has an overall better performance with lower error estimates. Generally, the satellite retrieved data performed well during the wet season but poorly in the dry season. The performance of both MODIS products over the region suggests they can be used at most locations with little error/adjustment.

DOI:
10.1007/s11869-023-01391-4

ISSN:
1873-9326