Известия Томского политехнического университета: Инжиниринг георесурсов (Aug 2016)
Studying the distribution of thermokarst lakes areas in arctic zone of Western Siberia and their dynamics by the ultrahigh resolution satellite images
Abstract
The relevance of the paper is caused by insufficiently studied regularities of distribution of sizes and dynamics of thermokarst lakes, considered as the most active sources of methane emissions to the atmosphere in the Arctic regions under global warming. The main aim of the study is the remote research of dynamics of thermokarst lakes and distribution of their areas in the Arctic zone of Western Siberia, based on middle and ultra-high resolution satellite images. Methods: methods of key (test) sites; remote method of research of thermokarst lakes fields, including small lakes, using satellite images of high and very high spatial resolution; method of multi-temporal satellite images for studying the lakes' dynamics; techniques of geographic information systems for the spatial analysis of data on thermokarst lakes obtained from satellite images. The results. The analysis of experimental data on the size of thermokarst lakes which area is from a few tens to hundreds of square meters, obtained by the ultra-high resolution images, showed that the histograms of size-distribution of small lakes in Arctic zone of Western Siberia allow their approximation both by power and exponential functions. Based on remote sensing studies of the dynamics of thermokarst lakes on multi-temporal images of medium resolution obtained for 1973-2013 in the Arctic zone of Western Siberia, the differences of the dynamics were determined in different landscape zones. In the area of the Arctic tundra of Western Siberia there is in average a tendency of growing total area of lakes, in the subarctic tundra there is the tendency to reduce it, and in the forest tundra the features of temporal changes of lake areas were not identified.
