Pan evaporation in Anhui Province decreased significantly over the past 45 years, with the most notable drop in summer. The trend was more pronounced in the north than in the south. Factors like temperature, sunlight, wind speed, and humidity all played a role in this decrease, with temperature showing a paradoxical relationship with evaporation. The study suggests that various climate factors influence evaporation in complex ways, leading to the observed trends in Anhui Province.