Two-year comparative study of snow cover dynamics and its impact factors on glacier surface

Snow cover on glacial surfaces is a sensitive environmental indicator. However, it is difficult to differentiate snow cover from a bare ice surface, and snow cover also changes rapidly during the melt season. Monitoring these dynamics requires sufficient time and spatial resolution; thus, traditional satellite data lack the necessary spatial resolution and rarely used to monitoring snow cover on glacier surface, which induced monitoring of snow dynamics on glacier is more challenging. Time-lapse photography has the advantage of obtaining images with high time and spatial resolution. By using an automated time-lapse digital camera, this paper documents two successive years snow cover dynamics on the Shiyi glacier and compared the meteorological conditions which induced different melt conditions. Monitoring indicate that the 2012 melt season experienced a higher snow cover fraction than the 2013 melt season because of a greater accumulated snow depth, lower air temperature and fewer sunlight hours. Successive photographs also indicate that, on the Shiyi glacier, atmospheric dust accelerates the snow melt speed and attenuates the snow depth. For the bare ice surface, the effects of atmospheric dust were reduced because the dusts were composed of Fine particles and are more easily washed away by melt water or rain. Studies on the Shiyi glacier indicate that the snow cover fraction is a key parameter that indicates the status of glacial accumulation or ablation.