Based on long-term remote sensing products, this paper constructs evaluation indicators for surface high temperatures and analyzes the distribution characteristics of surface high temperatures in Hunan Province over the past 20 years, aiming to provide technical references for agricultural production, disaster prevention and mitigation. Firstly, the daily surface high temperature dataset are calculated using long-term data regression of MYD11A1, MYD13A1 and MYD09GA from 2002 to 2021. The percentage method, percentile method and trend ratio method are used to construct remote sensing evaluation indicators for surface high temperatures, then the spatial and temporal distribution characteristics of surface high temperatures are analyzed. The results indicate that when using the proportion of areas with daily surface temperatures greater than or equal to 45 ℃ as the threshold for classifying surface high temperature levels on a daily scale, it aligns best with meteorological warning indicators. The annual maximum surface high temperature in Hunan Province showed a significant increase with 2013 as a turning point. The extreme threshold for annual surface high temperatures in Hunan Province (ranging from 40.2 to 64.1 ℃), determined using the percentile method, can serve as an evaluation metric for high temperature intensity. Additionally, using the trend rate of surface high temperatures in Hunan Province to evaluate the increase or decrease trends of annual surface high temperatures has good application value. Rapid warming in the Changsha-Zhuzhou-Xiangtan urban agglomeration and the Dongting Lake area, as well as extreme high temperatures in the Hengshao drought corridor, require special attention in the future.
