Spatial–Temporal Variation Characteristics of Different Grades of Precipitation in Changbai Mountain from 1961 to 2018

Changbai Mountain is an area that is sensitive to climate change. Under the influence of global climate change, the amount and intensity of precipitation are changing significantly in Changbai Mountain. Understanding the changes in the amount and days of the different grades of precipitation is of great significance for revealing the evolution of water resources in Changbai Mountain. Based on the daily precipitation data from the meteorological stations, the authors analyzed the temporal and spatial variations of the different grades of precipitation in Changbai Mountain from 1961 to 2018. From 1961 to 2018, over the Changbai Mountain, the annual precipitation showed a weak decreasing trend (−0.31 mm/a), precipitation days showed a significant decreasing trend (−0.16 d/a), and precipitation intensity showed an insignificant increasing trend. With respect to changes in the different grades of precipitation, the amount and days of low, moderate, and high intensity rainfalls show a decreasing trend, while the amount and days of rainstorm show an insignificant increasing trend. The decrease in the annual precipitation and precipitation days was mainly caused by the decrease in the precipitation and precipitation days of low, moderate, and high intensity rainfalls in Changbai Mountain. With respect to the precipitation changes in Changbai Mountain for different seasons, precipitation increased in spring and winter but decreased in summer and autumn.