Abstract:
Based on MODIS Enhanced Vegetation Index (EVI) and Land Surface Temperature (LST) data, spatial-temporal variation of agricultural drought on Central Yunnan Plateau during 2001-2020 was analyzed by calculating Temperature Vegetation Drought Index (TVDI). The results show that the average annual TVDI in the study area demonstrated an upward trend in the past 20 years, and the overall agricultural drought revealed a significant increasing trend. The agricultural drought was most severe in April, and least severe in October. The annual average values of TVDI ranged from 0.46 to 0.56, and the coverage area of moderate drought and severe drought showed an expanding trend. In Kunming and Qujing mainly occurred mild drought; in Yuxi mainly occurred moderate drought; in Chuxiong were alternately distributed mild drought and moderate drought; and the drought in the west of Central Yunnan Plateau had an increasing trend. The intensity of agricultural drought changed greatly in the northern part of Kunming and the western part of Yuxi, and in the Yuanjiang River Valley and the Jinshajiang River Valley; while in other regions, the change of agricultural drought gradually tended to be stable in the past 20 years. The agricultural drought centers in the study regions mainly moved southward first and then southwestward.