A sudden sea ice increase in the Baltic Sea in February 2011

Only a fortnight ago it looked as if the sea ice in the Baltic will end the season according average as indicated in Fig 1, showing1_ the ice cover on the 7th Feb. (jäätä) vs normal ( 11/Feb, right).On week later on the 14th the Gulf of Bothnia and the Gulf of Finland were fully covered with ice for the first time this year (Fig. 2 ; Finish ice map 14.Feb.- No.89). Last year this situation appeared early March 2010 (Click here ). However during the last two weeks the ice extended quickly southwards. About 250,000 square kilometres of the Baltic Sea are now covered by ice according to the Swedish Meteorological and Hydrological Institute (SMHI). The last time hat so much of the Baltic was frozen was the winter of 1986-87, when ice covered nearly 400,000 square kilometres of the sea’s surface. (see: Click here )

 2_11  3_11
14. February 2011 – Ice Report No.89 26. February 2011 – Ice Report No. 101
The Finnish Meteorological Institute; http://www.itameriportaali.fi/en/itamerinyt/en_GB/jaatilanne/

The quick extension over the last few days, is due to low temperature from Siberia to the Baltic countries. The cold is still present and forecast indicate hash freezing conditions (between high –3°C and low: -15°C) until early March. That will presumably mean that the 400,000 square kilometres of 1986/87 will be succeeded soon.

The sudden increase during the last few days is not so much an surprise if one recalls that Northern Europe from Great Britain to Murmansk experienced presumably in December 2010 the coldest December months during the last 100 years. For example, the United Kingdom claims that December 2011 was the coldest for 120 years. In particularly the sea ice conditions as per the 31 December 2010 had been extraordinary. At that time all conditions indicated for a record to come. For details see: “Record Sea 0228_No103Ice conditions for the Baltic Sea region ahead?” at :
http://www.2007seatraining.de/Archiv/dec2_10.html Instead the January and February had been modest in western Europe, only north-east of the river Oder the temperatures dropped sharply in February. The cold reached the Baltic countries at about 14th February.

Last year the winter condition had been deep wintry since the Climate Summit in Copenhagen in mid December 2009. Despite this severe condition for 10 weeks, the ice cover remained in the range of normal until the end of February 2010. Details here: “The coldest winter in the Baltic Sea region for 30 years, but where is sea ice in winter 2009/10?” Click here .

This year raises even more questions science should answer. For example which role plays shipping with regard to preventing the forming of sea ice, or even contributing to the freezing process.
However, as per 28th February 2011 (see Figure 4) it seems that the process of sea ice decrease e has started.

Posted_  01 March 2011