The study looked at data from the past 50 years in the west part of the Tianshan Mountains to understand changes in aridity. By analyzing precipitation, temperature, and evaporation data, researchers found that the region has a mix of semi-arid and semi-humid climates. Aridity levels varied across different areas within the region and showed a decrease over time, especially in the summer. The main reason for this change was a significant decrease in water surface evaporation.