Comparison of Landsat 8 and sentinel 3 in monitoring of agricultural drought. A study of Soroti district

Abstract

The aim of this research was to compare Landsat 8 and sentinel 3 images when monitoring agricultural drought in Soroti district. This research was based on the determination of the three agricultural drought indices i.e. Temperature Condition Index (TCI), Vegetation Condition Index (VCI) and Vegetation Health Index (VHI) which were produced from Land Surface Temperature (LST) and Normalised Vegetation Index (NDVI) of the downloaded images of both Landsat 8 and sentinel 3 with VHI being the basic index in monitoring agricultural drought. The images were processed using ArcGIS and SNAP soft wares for Landsat 8 and sentinel 3 images respectively. Monthly rain fall totals of Soroti district of year 2018 was used for validation and results showed that sentinel 3 images gave a better correlation of -0.68 when compared with rainfall values than Landsat images which had -0.443. The conclusion was that sentinel 3 is a better indicator of agricultural drought and hence better that Landsat 8 in its monitoring.