A recent study led by CHEN Yaning from the Xinjiang Institute of Ecology and Geography (XIEG) of the Chinese Academy of Sciences reveals that the frequency, intensity, and duration of extreme precipitation events (EPEs) in arid Northwest China have significantly increased due to global warming. These changes pose a serious challenge to the region's water resources and disaster management strategies. 

Their findings were published in the Journal of Hydrology.

The researchers conducted a comprehensive analysis of the spatiotemporal patterns of EPEs in the arid Northwest China and the mechanisms driving these changes. 

Using the CN05.1 high-resolution climate dataset and analyzing multiple large-scale circulation factors, the team examined six extreme precipitation indicators to determine trends in EPEs from 1961 to 2022. They also quantified the relationship between 13 climate factors and EPEs using the geographic detector model.

The researchers revealed that the number of continuous days without precipitation (CDD) is decreasing by an average of 0.65 days per year, while heavy rain days, annual total precipitation, and maximum daily precipitation are increasing by 0.067%, 0.49 mm, and 0.42 mm per year, respectively.

In addition, they found that sea surface temperature anomalies, particularly in the Atlantic, Indian, and Pacific oceans, play a crucial role. These anomalies trigger circulation changes that enhance water vapor transport to the arid Northwest, serving as a primary driver for the increasing intensity of EPEs.

"Our research highlights the complex interplay of factors driving the increase in extreme precipitation in this region," said LIANG Qixiang, first author of the study.

This study offers crucial scientific information for regional water resource management, flood warning systems, and ecological protection policies.

Schematic diagram of main processes affecting extreme precipitation in arid Northwest China. (Image by XIEG)