Temporal and spatial features and inter‐annual variability of wintertime snow mass balance over China

Abstract

ABSTRACTUsing observational data for 1979–2010, the temporal and spatial variations of wintertime (December–February) snow water equivalent (SWE) over China and their relations to the November SWE, wintertime snowfall, snow evaporation, sublimation and melting are investigated. The results revealed that the SWE is principally distributed in four snow regions of northwestern (NW) China, northeastern (NE) China, the Tibetan Plateau (TP) and the Yangtze–Huaihe River valley (YH). It is found that the impact of the November SWE is confined to the north of 42°N, while the impact of snowfall are relevant over all China, and the impacts of snow evaporation and sublimation are limited to NW, NE and the TP. The effect of snow melting is large in the YH but weak in other regions. On the inter‐annual timescale, the snow mass balance shows different features in different snow regions. The wintertime SWE is in line with snowfall. The November SWE has a major effect on the wintertime SWE in NW and NE but not in the TP and YH. The effect of meteorological factors on snow evaporation, sublimation and melting differs in different snow regions. Evaporation is mainly affected by vapour pressure deficit in NW and wind speeds in NE and the TP. Sublimation is controlled by air temperature in NW, wind speeds in NE, vapour pressure deficit in YH and air temperature, pressure and vapour pressure deficit in the TP. Melting is closely related with air temperature in the TP and net radiation in the YH.