Precipitation trend–Elevation relationship in arid regions of the China

Abstract

Based on monthly precipitation data at 128 meteorological stations in the arid regions of the China (ARC), we investigated that the regional characteristics of precipitation trend and the precipitation trend–elevation relationship during the period of 1961–2012. There is growing evidence that the elevation-dependent wetting (EDWE), which is the precipitation wetting trend is amplified with elevation. The precipitation trend increases significantly with elevation except for the altitude from 500 to 1500m, the highest correlation appears above 1500m, increases by 13mm/decade with each 1000m. With the elevation increasing every 1000m, precipitation tendency rate increases by 7mm/decade from 1000 to 2000m and increases by 10mm/decade from 2000 to 4000m. EDWE has an impact on the change of the cryospheric systems, ecosystems and water resources, especially in arid regions of China. We discuss mechanisms that contribute towards EDWE: water vapor changes and warming-driven water circulation speeds up. We suggest future needs to increase evidence of understand the EDWE in other mountainous regions, and its controlling mechanisms through integrated the observational network of surface in-situ climate observations, satellite data and high-resolution climatic modeling.