Using this graphic and referring to it is encouraged, and please use it in presentations, web pages, newspapers, blogs and reports.
For any form of publication, please include the link to this page and give the cartographer/designer credit (in this case Hugo Ahlenius, UNEP/GRID-Arendal)
Wang, M., Overland, J.E., Kattsov, V., Walsh, J.E., Zhang, X. and Pavlova, T. (2007). Intrinsic versus forced variation in coupled climate model simulations over the Arctic during the 20th century. J. Climate, 20(6), 1093-1107
Uploaded on Tuesday 21 Feb 2012
Arctic temperatures in the 20th century, modeled and observed
Hugo Ahlenius, UNEP/GRID-Arendal
Observed Arctic winter land temperatures and IPCC model recreations for the 20th century. Note that although these model runs are able to capture the range of Arctic warm and cold periods, the timing of the peaks varies, suggesting that the early 20th century warming was due to random causes, while the increases at the end of the century shown by all the models supports CO2 as an external forcing of the Arctic climate system.