Scientific publications

Long-term ice cover records from 38 freshwater lakes in Karelia were assembled and analysed. It is shown that lake-freezing dates depend on air temperature, latitude, elevation above sea level, and mean depth of a lake. An increase in air temperature leads to later freezing of lakes while an increase in the lake depth, elevation above sea level, or latitude stimulate earlier freezing. Essential distinction of processes of freezing and ice break-up in large deep-water and shallow reservoirs is noted. The results of 15-years field experimental investigations of ice properties of small shallow Lake Vendyurskoe are shown. The spatial and temporal variability of the thickness and structure of snow-and-ice cover is shown. The ranges of variations in the albedo of snow and ice for a wide spectrum of the state of surface are presented. The results of field experiments aimed to determine the degree of absorption of solar radiation by snow and ice are presented. The effective extinction coefficient of solar radiation by snow and ice is determined. The present study is supported by the Russian Academy of Sciences and Russian Fund of Basic Research (project 07-05-00351).