Pan evaporation in the upper Yangtze River region has changed significantly from 1980 to 2008. The researchers found three climate regions with different evaporation patterns: decreasing in the east and west, and increasing in the middle. Factors like solar radiation, wind speed, and humidity influenced these changes. The water cycle was affected, with increased rainfall and runoff in some areas, and decreased in others. Overall, the study shows how changes in evaporation impact the water cycle in the upper Yangtze River region.