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7. Ice Conditions in Szczecin Lagoon and Pomeranian Bay During the Winter of 
2000/01 
In the ice winter of 2000/01, the reduced ice sum (a measure of the length of the ice winter) deter 
mined for the coastal waters of Mecklenburg - Vorpommern was one day. The accumulated 
areal ice volume (a measure of the severity of an ice winter) reached a value of 0.03 m, allowing a 
classification of the 2000/01 season as a very weak ice winter. 
Meteorological conditions in the 2000/01 winter period (information from Deutscher Wetterdienst - 
German Weather Service) 
November 2000 
November 2000 was very mild. The maximum daily temperatures in the area of the Szczecin Lagoon 
ranged between 6 and 12 °C. The highest temperature was recorded on 29 November, when south 
erly winds led to a daily mean temperature of 9.8 °C in Ueckermunde. Air temperatures at night were 
also positive, and freezing temperatures occurred only near the ground. 
December 2000 
The first half of the month was unusually mild, with air temperatures exceeding the long-term refer 
ence values by about 5 °K. On 12 December, subtropical maritime air was temporarily transported 
from the Bay of Biscay to Central Europe at the edge of a large depression system over Northern 
Europe. In the area of the Szczecin Lagoon (Ueckermunde), daily maximum temperatures of 13 °C 
were reached on 13 December. During the next days, colder maritime air from the north-west flowed 
into this area, and air temperatures dropped to normal seasonal values. From 19 December, the anti 
cyclone over Northern Europe influenced large areas of Europe. On 22 December, its centre was lo 
cated over Poland. The daily minimum air temperature of -6.4 °C was measured in Ueckermunde on 
23 December. During the next days, the high-pressure system moved southeastwards, and low- 
pressure systems influenced the weather in the area of the Szczecin Lagoon until the end of the 
month. Air temperatures were around 0 °C. 
January 2001 
In the first decade of January, the low-pressure systems continued to influence the weather in Cen 
tral Europe, with relatively warm and humid air flowing into the coastal regions. A strong anticyclone 
developed at the beginning of the second decade, which was located between Iceland and Scotland 
on 10 January. On the following days, it moved across the North Sea toward the Baltic, causing an 
inflow of Arctic air which determined the weather in Central Europe until 17 January. Night frosts oc 
curred in all nights from 11 to 23 January, and on 5 days during this period below-zero temperatures 
were also recorded during the day. The last days of January again saw positive air temperatures in 
Ueckermunde, so that also the second month of winter was generally too mild. 
February 2001 
Negative daily mean air temperatures were recorded in Ueckermunde at the beginning and end of 
the month, with some heavy snowfalls. On 3, 4, and 24 February, the maximum temperatures re 
mained below zero. From 6 February, however, inflowing subtropical air led to mild weather. Until 22 
February, the air temperatures were clearly above 0 °C. Also the last winter month thus was about 
1 °K too mild as compared to the mean value of the normal series. 
March 2001 
After the winter months which were much too warm, it was the first month of spring which brought 
lower temperatures again, about 0.5 °C below the reference value in the coastal areas. Frost was 
recorded in 16 nights, and negative daily mean air temperatures occurred on 10 days. Surface water 
temperatures in the inland waters of Mecklenburg-Vorpommern, at 1.4 - 4.2 °C, were about normal. 
Negative deviations were only observed in the first decade of March (LUNG, 2001). 
According to information from the Deutscher Wetterdienst the mean air temperature and number of 
days with negative daily mean air temperature for the area of Szczecin Lagoon in the winter months 
of 2000/01 were as follows: 
Table 7.1. Air temperatures in °C for the station Ueckermunde in the winter of2000/01