Exploring Drought Characteristics In Vietnam During The Period 2001 – 2022 Using Modis Images

Abstract

Natuaral disaster, especially drought is one of big problem in Vietnam in many years, mainly responsible for serious damaged for the agriculture and the economy. This study focuses on exploring the trend of drought phenomenom monthly from 2000 to 2022 in the country, using the remote sensing MODIS MOD09GQ and MOD11A1 daily data products. The research estimate the severity of drought characteristics from using the Temperature Vegetation Condition Index (TVCI), which is sorted from extremely dryness to extremely wet. The TVCI is computed on a linear regression of the relationship between the Normalized Difference Vegetation Index (NDVI), derived from red and near infrared reflectance data, and the Land Surface Temperature (LST), derived from thermal reflectance data. After analyzing the collected data, the result come up with the expanding in drought from vertical direction from the north to the south of the country, corresponding with the no drought – light drought to serve drought – very serve drought. After analyzing, the result come up with 48.22% of Vietnam is in moderate drought while 18.96% of the section is in serve drought, and 4.16% in very serve drought condition. In TVCI differencing, approximately 56.71% of the land coverage is in positive change when showing increase in TVCI intensity. The drought problem in Vietnam is caused by the steady increase in LST, as an effect of climate change, and the movement of land cover distribution in enlarging the density of urban and built-up area while restricting coverage of vegetation and plants, as well as croplands, and water bodies area.