Changes in seasonal snow liquid water content during the snowmelt period in the Western Tianshan Mountains, China

Abstract. Snow liquid water content is a very important parameter for snow hydrological processes, avalanche research and snow cover mapping by remote sensing. Snow liquid water content was measured with a portable instrument (Snow Fork) in the Tianshan Station for Snow Cover and Avalanche Research, Chinese Academy of Sciences during the snowmelt period in spring 2010. This study analyzed the temporal and spatial distribution of snow liquid water content in different weather conditions. The average liquid water content of snow in the whole layer exponentially increased and can be calculated using a regression function of prior moving average temperature. The proportion of net radiation, sensible heat flux and latent heat flux in total energy changed in different snowmelt period. During the pre-snowmelt period (0.3% ≤ W_vol < 1%), snow liquid water content and its temporal variation were relatively small, with liquid water accumulated in the coarse snow layer. During the mid-snowmelt period (1% ≤ W_vol < 2.5%), the variation was significant in the upper layer and decreased drastically during the snowfall and the following one to two days. Only the temporal variation decreased after rain or snow (ROS) events. During the late-snowmelt period (W_vol ≥ 2.5%), the distribution and variation of every snow layer showed a~uniform trend, and the effect of ROS events on liquid water content only occurred during rainfall and snowfall.