RIVER FREEZE-UP AND BREAKUP DATES IN THE LATE 20th CENTURY AND THEIR POSSIBLE CHANGES IN THE 21st CENTURY

B. M. Ginzburg

Changes in freeze-up and breakup dates in 2000 are determined in comparison with the accepted norms of the present climate (1961—1990). They are statistically significant for most rivers of European Russia, Belorussia, and Western Siberia and are close to changes in the previous 100 years. The accuracy of the earlier suggested forecasts of these changes is assessed. Based on the calculations performed by the MGO climatologists using a simple model of freeze-up and breakup of ice cover, probabilistic characteristics of the future ice regime on the rivers throughout the 21st century have been derived. The perspectives of favorable changes in the navigation period, especially on the European rivers, are considered.