Spatial and temporal characteristics of precipitation over the Three-River Headwaters region during 1961–2014

• Detection of spatial-temporal variation of precipitation over the TRH region.
• Investigation of the correlation of precipitation with elevation.
• Statistical equations based on longitude, latitude and elevation were established.
• Discussion of the causes and impacts of the changing precipitation.

Study regionThree-River Headwaters (TRH) region, China.Study focusPrecipitation is regarded as the basic component of the global hydrological cycle. This study investigated the spatial and temporal characteristics of precipitation over the TRH region during 1961–2014, based on the observed data of 29 meteorological stations.New hydrological insights for the regionThe results showed that: (1) temporally, the TRH region has experienced a significant increasing trend in the annual precipitation (p < 0.1) during 1961–2014, especially in the dry season (p < 0.01). (2) Spatially, the mean annual precipitation (MAP) in the TRH region showed the southeast-to-northwest decreasing trend and the annual precipitation recorded at most stations (i.e., 26 in 29) presented the increasing trends. (3) A close correlation of the MAP with elevation was found, that is, a low-to-high increasing trend below 3800 m but an inverse correlation above 3800 m; in addition, statistical equations to estimate precipitation with high R2 values were established based on longitude, latitude and elevation. (4) Characteristics of related meteorological variables and possible impact of precipitation on runoff were analyzed and discussed. These results would be valuable for the researchers to better understand the changing characteristics of precipitation and for the managers to make better decisions in the future.