For weather stations from Agder to Trøndelag, the average temperature in the winter months of December, January and February will be the highest ever.
Gardermoen will for the first time experience that the average temperature for the winter is above zero degrees. It does not classify for winter in meteorology. A winter day is defined as a day with an average temperature below zero degrees. It writes the Meteorological Institute in a press release.
Mildest winter in eight counties
Records are set in eight counties: Innlandet, Viken, Oslo, Vestfold and Telemark, Agder, Rogaland, Vestland and Trøndelag. Exactly how high the average temperature in these places was in December-February, we only know when the month of February is over. Nevertheless, these places have had such a high average temperature so far that we can already state that they have had the mildest winter since the measurements started. We have only looked at measuring stations that have been in operation for more than 30 years.
This winter, many low pressures have passed from the southwest, bringing with them mild sea air, and this has led to high temperatures in southern Norway.
Heat records are increasing in numbers
– We have mild winters with a lot of low pressure activity and high temperatures from time to time, but it has never been as mild as this year, says Reidun Gangstø Skaland, climate researcher at the Meteorological Institute.
The mild winters will be even milder than they would have been without climate change, in line with the forecasts for the future climate.
– A single winter can not be directly linked to climate change, because we will always have natural variations. Next winter can be very cold. But we can state that we are getting more and more heat records, while cold records are becoming rarer. In 2019, for example, we set 159 heat records, but only 27 cold records. The increase in heat records over time is due to global warming, says Skaland.
Both Blindern and Tryvannshøgda will have a mild winter. The measurements go back to 1937 and 1943, respectively. We have never before measured so few winter days at Blindern in Oslo as this season, and for the first time the average temperature in both December, January and February is above zero degrees. The blind has never before in a winter period measured so few days with five degrees Celsius or more, and we have also never measured so few days with measurable snow depth.
Here, Gardermoen, Rygge and Asker have registered their mildest winter ever, with measurement series dating back to the 1940s and 50s. Gardermoen will for the first time have an average temperature of over zero degrees, and has thus not had winter so far this year.
In Innlandet county, seven records are set. The measuring stations at Dovre, Drevsjø, Kise at Hedmark, Østre Toten, Lillehammer, Vest-Torpa and Fagernes all set records for the highest average temperature in the winter period.
Vestfold and Telemark
Two stations in the county set records: Melsom and Færder lighthouse, the latter with a series of measurements dating back to 1885.
In Agder, five measuring stations set a record. Oksøy lighthouse has measurements dating back to 1876, and this year’s winter will be the warmest since then. The same applies to Torungen lighthouse, which has been in operation since 1867. Landvik, Lindesnes lighthouse and Lista lighthouse also set records.
In Western Norway, it has been the mildest winter ever at Sola and at Utsira lighthouse. The latter has measurements dating back to 1867.
Records are set here at Slåtterøy lighthouse, Takle in Gulen and at Ytterøyane lighthouse. It is also possible that the two Bergen stations Flesland and Florida manage to break the record from the winter of 2013/14, but they probably do not.
In Trøndelag county, there will be seven records for the mildest winter: Sula, Snåsa, Ørland, Halten lighthouse, Buholmråsa lighthouse, Nordøyan lighthouse and Sklinna lighthouse set all records. Nordøyan lighthouse has measurements dating back to 1900.
The calculations of the records are based on data up to 25 February. The final figures for February are ready on Monday 2 March at 12.00.
Text: Amalie Kvame Holm, Jostein Mamen.
Norwegian Meteorological Institute