FEATURES OF THE SNOW COVER FORMATION IN SIBERIA AND THE RELATIONSHIP WITH THE ATMOSPHERICS DYNAMICS ANOMALIES IN THE NORTHERN HEMISPHERE

Abstract

Variation of the snow cover extent and the dates of the beginning and end of its formation in Western Siberia (WS) for the fall-winter season was analyzed. We used the NOAA satellite data on the snow cover extent in Northern Hemisphere and data from meteorological stations from the RIHMI-WDC dataset. An increase of the interannual variation of the dates of the beginning and end of the snow cover formation was obtained. For the northern WS territories and territories located on significant heights, a later onset of snow cover is shown in the NOAA data compared to stations observations. Using the ERAInterim reanalysis and NOAA data, we also analyzed the features of the atmospheric modes of variability and wave activity, which are manifested for the anomalously rapid snow cover formation in the WS. The results obtained indicate the insignificance of the influence of the anomalies in the rate of the WS snow cover extent increase. We also suggest that the snow cover formation anomalies are a consequence of the atmospheric state anomalies on a hemispheric scale.