Ice Conditions along the Estonian Coast in a Statistical View

The paper presents the results from analysis of long-term (100-year) time series of freezing, fast ice formation, disappearance of fast ice, break-up and ice thickness for eight stations situated along the Estonian coast in the Gulf of Finland and Gulf of Riga. Most of the data have not been published yet. Basic statistics: average, standard deviation, maximum, minimum and frequency histograms are given. On average ice has formed in the Gulf of Finland three weeks later compared with the Gulf of Riga. The range of variation of the freezing date is very large, 3-4 months, with maximum value of standard deviation 29 days (Tallinn). The average ice seasons last 4-5 months; the range is 0- 7 months. Statistically significant trends are found in time series of date of freezing for Sorve and Virtsu and in time series of ice break-up for Kihnu and Virtsu, both trends toward shorter ice seasons. Correlation coefficients of different time series are varied through 0.03-0.90.