Distribution of snow cover over Northern Eurasia

Abstract

Based on observation data the spatial variability and long-term trends of snow depth, snow water equivalent and number of days with snow coverage ≥50% for Northern Eurasia are estimated. The significance of continental snow cover variability over Northern Eurasia is illustrated by comparison with snow cover variability of the northern part of North America (Canada). The fundamental scientific problem of our investigations is revealing spatial and temporal changes of snow cover under the present climate conditions. The snow cover depends on a climate on the one hand and appreciably defines a hydrological regime on the other hand and, thus, the snow cover is a good indicator of changes in the condition of an environment. In this case the condition of the snow cover of the Northern hemisphere on an example of Northern Eurasia within the boundaries of the NIS and the northern part of North America within the boundaries of Canada is investigated. The novelty of the work, in particular, consists in the attraction to the analysis of a lot of long-term data on the snow cover of two continents. As a result the general regularity of spatial heterogeneity and the long-term variability of snow stocks were revealed.

Spatiotemporal variability of snow depth across the Eurasian continent from 1966 to 2012

“…This may be caused by using a different number of stations and covering different study periods. The long-term mean annual snow depth from the present study was approximately 5-10 cm higher than the results from Kitaev et al (2005) and Bulygina et al (2011) over northern Eurasia. These discrepancies may result from differences in the time frame of data collection, the number of stations, calculation methods, and data quality control.…”

“…These discrepancies may result from differences in the time frame of data collection, the number of stations, calculation methods, and data quality control. For example, Kitaev et al (2005) investigated historical changes in annual mean snow depth spanning 65 years from 1936 to 2000, while the present study covered 47 years from 1966 through 2012. We intentionally did not use the earlier data due primarily to data quality.…”

“…10). This is because the increased precipitation falls as snow in cold areas where the increased temperature is still below freezing (Ye et al, 1998;Kitaev et al, 2005). Warmer air leads to a greater supply of moisture for snowfall and hence the snow depth still increases (Ye et al, 1998).…”

“…Changes in snow depth are primarily affected by air temperature and precipitation. Ye et al (1998) and Kitaev et al (2005) showed that higher air temperatures caused an increase in snowfall in winter from 1936 through 1995, and thus greater snow depth was observed in northern Eurasia. Snow depth distribution and variation are controlled by terrain (i.e., elevation, slope, aspect, and roughness) and vegetation Grünewald et al, 2014;Revuelto et al, 2014;Rees et al, 2014;Dickerson-Lange et al, 2015).…”

“…These measurements provide valuable data and information for snow cover phenology and snow cover change detection. Many studies on snow depth have focused on local and regional scales over Russia (Ye et al, 1998;Kitaev et al, 2005;Bulygina et al, 2009Bulygina et al, , 2011Brasnett, 1999) and the Tibetan Plateau (TP) (Li and Mi, 1983;Ma and Qin, 2012) and have revealed significant regional changes. It has been reported that annual mean snow depth has increased in northern Eurasia and the Arctic during the last 70 years (Ye et al, 1998;Kitaev et al, 2005;Callaghan et al, 2011;Liston and Hiemstra, 2011) with large regional differences (Bulygina et al, 2009(Bulygina et al, , 2011Ma and Qin, 2012;Stuefer et al, 2013;Terzago et al, 2014).…”