Sea Ice in Denmark 1940 indicate to

Naval war activities in North- and Baltic Sea during previous months.

 First ice was reported around mid December, which increased soon in the inner and closed waters and later on outside this area. The number of ice days had generally been large, a maximum of 115 days. While 34 stations reported more than 100 days, 99 stations reported 75-100 days. Last ice was reported in the Sounds, on the 19^th of April 1940. Due to an early start of the winter, there were the severest ice conditions on sea for many decades. The lowest temperatures recorded were in December –22.2°C, in January –24.3°C, in February –27.4°C, and in March –22.0°C. Ships were to be convoyed and accompanied by icebreakers through the Kattegat East-channel if the supplies were to reach Copenhagen. These proceedings were not accomplished without damages to ships convoyed, as well as to accompanying icebreakers. The coldest month in Copenhagen, viz. February, usually has a mean temperature of 0°C. It was the coldest ever measured winter with minus 3.5°C below average.

Source for the layout of graphic: Det Dansk Meteorologiske Institute (1940)

Chapter: 2_16

Book Page: 85a

File: 980 SeaIce_Det Dansk

Image: 2010/www.seaclimate.com