How is the precipitation distributed vertically in arid mountain region of Northwest China?

Precipitation in the arid region of Northwest China (NWC) shows high spatial and temporal variability, in large part because of the region's complex topography and moisture conditions. However, rain gauges in the area are sparse, and most are located at altitudes below 2000 m, which limits our understanding of precipitation at higher altitudes. Interpolated precipitation products and satellite-based datasets with high spatiotemporal resolution can potentially be a substitute for rain gauge data. In this study, the spatial and temporal properties of precipitation in the arid region of NWC were analyzed using two gridded precipitation products: SURF_CLI_CHN_PRE_DAY_GRID_0.5 (CHN) and Tropical Rainfall Measuring Mission (TRMM) 3B43. The CHN and TRMM 3B43 data showed that in summer, precipitation was more concentrated in southern Xinjiang than in northern Xinjiang, and the opposite was true in winter. The largest difference in precipitation between mountainous areas and plains appeared in summer. High-elevation areas with high precipitation showed more stable annual precipitation. Different sub-regions showed distinctive precipitation distributions with elevation, and both datasets showed that the maximum precipitation zone appeared at high altitude.