Ice winter severity in the western Baltic Sea in the period of 1301–1500: comparison with other relevant data



A 700-year time series of ice winter severity index (referred to as Ice Index in this contribution) which additionally includes the period from 1301 to 1500 is now available for the region of the western Baltic. It is compared with air temperature time series, NAO, and other relevant indices. As expected for a regional time series, agreement with larger-scale northern hemisphere temperature variations is found only on longer time scales. Very good correspondence, even on shorter time scales, is obtained using a geographically close time series of annual mean air temperatures for the Low Countries (The Netherlands and Belgium). Although the data basis for the additionally included 1301–1500 period is quite sparse, there is also very good correspondence in this period. Correlation with the NAO Winter Index is generally negative, but the correlation is not significant for earlier periods. Copyright © 2011 Royal Meteorological Society