This post refers to my analysis of recorded monthly mean temperature trends at Vardo in far northern Norway. The station was established in 1829. The analysis used raw data (as recorded, without any adjustments) as published by KNMI (the Dutch Meteorological Institute). Polynomial curves of best fit were added to the plots.
Vardo is a small town on a small island (Vardoya) in the Barents Sea in the extreme north-east of Norway. Vardo is about 600 km north of the Polar circle.
Over the 1829-2016 period (a period of 188 years) the years are 94% complete.
Vardo has a polar / sub-polar oceanic climate, but with cold winters and mild summers. The port remains ice-free throughout the year. Mean monthly temperatures vary from -5.5 degC (in February) to +9.3 degC (in August). Extreme monthly mean temperatures recorded are -11.2 degC (in February 1844) to +13.5 degC (in July 1960).
Mean, Maximum and Minimum Monthly Temperatures
Plots are shown below for annual mean temperature and the monthly mean temperature for each of the 12 months. A polynomial trendline was fitted to each graph. A comparison of the monthy trendlines are also presented. It should be noted that the trendlines (in red) can sometimes be misleading at either end of the series as the line is very dependent on the temperature values in individual years (this sensitivity does not occur away from the start and end of the series).
Annual Mean Temperatures
Monthly Mean Temperature Trendlines
- The plots show cyclical monthly trendlines in most months, with Lows in about 1870 and 1880 and a High in about 1940.
- In most months there has been an increase in monthly mean temperatures since 1940 of between 0.0 degC and 2.0 degC.
- The average annual temperature trend since 1829 is about +1.5 degC/century.
- There have been increases in temperatures in recent decades which have not yet reached cyclical Highs.
Vardo is one of 257 stations, worldwide, for which I have analysed long-term temperature trends. The analyses at 50 representative stations are summarised in the blog post: world-50-temperatures
Please let me know what you think of my analyses. firstname.lastname@example.org
This article was written by Brian Gunter of Narooma, NSW, Australia. In his previous life Brian was an engineering hydrologist involved over many years in the analysis of rainfall and river flow data for the planning of water resources projects in Australia, Asia and Africa. In recent years he has been one of the Marine Rescue NSW (previously Royal Volunteer Coastal Patrol) volunteer weather observers who operate the Narooma station for the Australian Bureau of Meteorology.