Brian Gunter, Narooma, NSW, Australia http://members.westnet.com.au/brigun/rothera-temps.html
"Trends are not always trendy"
Has the Antarctic continent become significantly warmer in recent years?
Here is a detailed analysis of the temperature data recorded at Rothera station since 1946.
Rothera station, in Antarctica, was operated by the United Kingdom since February 1950. The station is located on an island off the Antarctic Peninsula (see map) with coordinates -67.75°N -68.13°E.
The raw data were extracted from the website of the Royal Dutch Meteorological Institute (KNMI).
Graphical plots are presented below of values of mean temperatures for each of the 12 months and also for each year (January-December).
A polynomial trend line was fitted through each of the sets of data.
This study is a more detailed analysis of temperature trends that I have made for 13 long-term stations in Antarctica. http://members.westnet.com.au/brigun/antarctica-temps.html That study showed that mean summer, winter and annual temperatures at 10 of the 13 stations also had essentially zero temperature trends over the past 60-70 years. The three stations located on the more-northerly Antarctic Peninsula had significant increased temperature over that same period.
The temperature at Rothera station has increased over the past 70 years, but since 1970 this is only in May.
The May temperature has increased by about 4.5°C over the past 70 years.
January and February temperature show a cyclic trend with a low around 1960 and a high around 2000
The other nine months have near-zero trend since about 1970, although most have lower temperatures prior to 1970.
So, there is evidence of a significant increase in the temperature at Rothera station over the past 70 years, but this is mainly in May!
ANNUAL AND MONTHLY TEMPERATURE TRENDS AT DUMONT D'URVILLE STATION, ANTARCTICA
This article was written by Brian Gunter of Narooma, NSW. 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 Bureau of Meteorology.
1 June 2015