High-elevation landforms are experiencing more remarkable wetting trends in arid Central Asia

Since the 1980s, a warming and wetting trend in arid Central Asia (ACA) has been widely reported. However, no consistent knowledge has been presented about whether warming and wetting trends are evenly distributed throughout ACA or whether there are noticeable topographical differences. We combined the ERA5-Land reanalysis dataset and data from Google Earth Engine to analyze the topographic differences of ACA from 1981 to 2020. The findings indicate that significant (p < 0.05) warming has a broader geographic scale in ACA and that warming rate of low-elevation landforms (high plains and hills) is higher than that of high-elevation landforms (mountains and tablelands). However, the wetting trend does not follow this pattern. By contrast, high-elevation landforms have a higher wetting rate than low-elevation landforms and are the main areas of wetting. Additionally, low-elevation landforms continue to maintain the warming and drying trends. Notably, the wetting trend of high-elevation landforms is amplified with altitude. Meanwhile, the wetting trend is negatively related to the warming trend (p < 0.01) across the entire elevation range. Collectively, the findings provide new insights into the current research hotspot of ‘warming–wetting’ trend in ACA and highlight the differences in the responses of different landforms to climate change.