Application of Landsat remote sensing data to assess drought risk in Ha Tinh province

Abstract

Drought is a complex natural phenomenon, forming slowly and causing severe impacts on both the living environment and people's production activities. It is necessary to research technologies that can identify the current situation and early warning or predicting the risk of drought. So far, many approaches and methods in evaluating, monitoring, and forecasting drought have been studied and utilized. Among these, research focusing on constructing and calculating drought indices based on data from satellite imagery has significant advantages in assessing the extent of drought over large territories. In this paper, the Vegetation Temperature Condition Index (TVDI) for Ha Tinh province was determined through the Normalized Difference Vegetation Index (NDVI) and Land Surface Temperature (LST) extracted from Landsat 8 OLI-TIRS data. The results show that the NDVI values range from -0.278 to 0.639, LST values range from 17.23 to 39.98 °C, and TVDI values range from 0 to 1.0. Furthermore, the classification of drought severity also indicates that most of the Ha Tinh province experiences mild drought (69.11 %) and moderate drought (15.52 %) across agricultural land areas. Severe and extreme drought (1.19 %) only occurs sporadically at specific points in coastal areas.