• Brohan, P. and S. F. B. Tett, Twentieth century surface temperatures from climate models and observations, G. R. L.. Submitted.

A set of all-forcings simulations of the 20th century global mean surface temperature changes from various coupled General Circulation Models (GCMs) is available from the PCMDI archive produced as part of the IPCC 4th Assessment Report work. Results from this set of models agree very closely with the observations.
The range of results expected given the uncertainties in the observations and the model forcings is wider than that observed, so the models are surprisingly good. Although the agreement over the century is good, there are notable differences between the observations and the collective response of the models in two places: the times of volcanic eruptions, and around 1940. The first suggests that the models may be too sensitive on short timescales, and the second may indicate a weakness in the observations.

Last Updated: 2007-02-27 02:00:04