Spatiotemporal Changes of Snow Depth in Western Jilin, China from 1987 to 2018

Seasonal snow cover is a key global climate and hydrological system component drawing considerable attention due to global warming conditions. However, the spatiotemporal snow cover patterns are challenging in western Jilin, China due to natural conditions and sparse observation. Hence, this study investigated the spatiotemporal patterns of snow cover using fine-resolution passive microwave (PMW) snow depth (SD) data from 1987 to 2018, and revealed the potential influence of climate factors on SD variations. The results indicated that the interannual range of SD was between 2.90 cm and 9.60 cm during the snowy winter seasons and the annual mean SD showed a slightly increasing trend (P > 0.05) at a rate of 0.009 cm/yr. In snowmelt periods, the snow cover contributed to an increase in volumetric soil water, and the change in SD was significantly affected by air temperature. The correlation between SD and air temperature was negative, while the correlation between SD and precipitation was positive during December and March. In March, the correlation coefficient exceeded 0.5 in Zhenlai, Da’an, Qianan, and Qianguo counties. However, the SD and precipitation were negatively correlated over western Jilin in October, and several subregions presented a negative correlation between SD and precipitation in November and April.