Arid Zone Research ›› 2025, Vol. 42 ›› Issue (8): 1394-1403.doi: 10.13866/j.azr.2025.08.04

• Weather and Climate • Previous Articles     Next Articles

Temporal and spatial variation characteristics of extreme precipitation in the eastern Hexi Corridor

YANG Xiaoling1,2(), CHEN Jing1(), ZHAO Huihua1, MA Zhonghua1, WU Wen1   

  1. 1. Wuwei National Climate Observation Platform, Wuwei 733099, Gansu, China
    2. Lanzhou Institute of Arid Meteorology of China Meteorological Administration, Key Laboratory of Arid Climate Change and Reducing Disaster of Gansu Province, Key Laboratory of Arid Climate Change and Disaster Reduction of China Meteorological Administration, Lanzhou 730020, Gansu, China
  • Received:2025-03-14 Revised:2025-05-25 Online:2025-08-15 Published:2025-11-24

Abstract:

Extreme precipitation events have increased significantly with global climate warming, leading to serious floods and other natural disasters. Studying extreme precipitation events is conducive to providing forecasts and early warnings, predicting extreme precipitation, and assessing disaster prevention capacity. Using daily precipitation data from five meteorological stations in the eastern Hexi Corridor, Gansu Province, China during 1961-2023, various indices were used to first study the long-term trends of extreme precipitation with climate change in this region and then qualitatively evaluate the contribution of precipitation of different grades to total precipitation using the inverse distance weight interpolation method, linear tendency method, Pearson correlation coefficient, and cosine similarity coefficient. The results illustrated that: (1) Extreme precipitation indices increased from north to south in the eastern Hexi Corridor, and southern mountainous areas and alpine mountainous areas were identified as high value areas of extreme precipitation. (2) All extreme precipitation indices increased over time, and the climate tendency rates of total precipitation, moderate rain and above precipitation, and strong precipitation were greater than those of the other precipitation indices. The increases of the other extreme precipitation indices were significant, excluding the intensity of moderate rain and above precipitation. (3) Total precipitation exhibited significant positive correlations with the other precipitation indices, and strong precipitation and moderate rain and above precipitation exhibited greater correlation coefficients with total precipitation than did the other precipitation indices. The trend similarity coefficients between total precipitation and the other precipitation indices all exceeded 0.980. These findings indicate that various precipitation indices had positive contributions to total precipitation, with strong precipitation and moderate rain and above precipitation having greater contributions to total precipitation than the other indices.

Key words: extreme precipitation index, change characteristics, Pearson correlation, cosine similarity coefficient, Hexi Corridor