The study analyzed 46 years of data from 79 weather stations in Jiangxi province to understand changes in evaporation rates and their influencing factors. They found that annual evaporation decreased by 4.57mm per year, with most stations showing a decrease. The main factors affecting evaporation were sunshine duration, wind speed, and relative humidity. The southwest and Poyang Lake region were more affected by humidity and wind speed, while the province as a whole was influenced by sunshine. The decrease in evaporation was linked to lower sunshine and wind speed, and higher humidity. A formula using sunshine, wind speed, and humidity accurately predicted average annual evaporation in the region.