Comparison of Land Surface Temperature Derived from Landsat 7 ETM+ and Landsat 8 OLI/TIRS for Drought Monitoring

The thermal infrared bands of Landsat 7 ETM+ and Landsat 8 OLI/TIRS have ability to provide Land Surface Temperature (LST) information. This information is important to map and monitor Earth surface's temperature-related events such as drought. However, these two Landsat sensors have different conversion methods of deriving LST information from their image pixels. Landsat 7 ETM+ applies a simple algorithm using single thermal band to produce an index of surface temperature; while Landsat 8 TIRS applies two thermal bands and a more sophisticated Split Windows Algorithm (SWA). This research aims to compare and contrast the ability of Landsat 7 ETM+ and Landsat 8 OLI/TIRS to map LST for drought monitoring in part of East Java Province, Indonesia. Drought detection was conducted using two different algorithms, namely Temperature Condition Index (TCI) with a range of values from 0-100 and Crop Water Stress Index (CWSI) with a range of 0-1. These algorithms have an opposite index value explanation; zero in TCI indicates drought condition, but wet condition in CWSI. The differences in the LST results from Landsat images showed that SWA method provides more similar results to the corresponding land cover conditions as compared to the result of Landsat 7 ETM+. Drought detection results demonstrate that TCI and CWSI would be optimally useful for area have a potential drought. Both methods have similar results in terms of the condition of Land Surface Temperatures. © Published under licence by IOP Publishing Ltd.