Assessing density of the lakes in West Siberian Plain basing on the Global Surface Water data

Abstract

Basing on the Global Surface Water data set on the Earth’s inland waters, a description of the calculation method for the density of the lakes is provided. The technique is based on the calculation of the water surface area in a local neighborhood by the sliding window method and on the sequential application of a number of standard geospatial analysis operations. The method allows obtaining cartograms of surface-grading with a resolution of 200 to 10 000 m in any area. Using the example of West Siberian Plain, the heterogeneity of the lakes’ spatial distribution is assessed. On the basis of comparison with old results (received 40 years ago), we can distinguish the general trend of dewatering, which is manifested for off-grained back-ground areas in reducing the share of lakes from 2,2 to 1,71 %. The analysis of detailed cartograms at the 1000 and 2500 m resolution allows correcting the boundaries of large geomorphological elements, such as blowing corridors, hollows of glacier water, and areas with the highest ice cover glaciation.