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Modeling European Temperatures: CMIP5 Biases and Uncertainty
Cattiaux, J., Douville, H. and Peings, Y. 2013. European temperatures in CMIP5: origins of present-day biases and future uncertainties. Climate Dynamics 41: 2889-2907.

The authors write that "recently, modeling groups have provided an ensemble of new simulations for various future [CO2] concentration scenarios, within the framework of the Coupled Model Intercomparison Project (CMIP5)." And they thus take it upon themselves "to document the performance of this new generation of GCMs in simulating present-day features of European temperatures."

What was done
In this self-imposed task, Cattiaux et al. evaluated 33 GCMs that participated in the CMIP5 project, based on comparisons they made between various model output parameters for the period 1979-2008 and corresponding real-world observations.

What was learned
The three researchers report that (1) "on average, CMIP5 models exhibit a cold bias in winter, especially in Northern Europe," that (2) "they over-estimate summer temperatures in Central Europe," that (3) they predict "a greater diurnal range than observed," and that (4) "in winter, CMIP5 models simulate a stronger North Atlantic jet stream than observed."

What it means
In light of the fact that the parameters evaluated by Cattiaux et al. were rather basic - almost mundane, in fact - it is surprising to find that the latest and greatest in GCMs did not come through with flying colors.

Reviewed 5 March 2014