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Updated 12 October, 2003

US National Assessment of
the Potential Consequences
of Climate Variability and Change
Model Validation: Model Biases


The following figures are differences between model and VEMAP observational data from 1961-1990.  The temperature units are in degree F.  Mean temperature is calculated as the mean of the minimum and maximum temperatures, so that the model data is consistent with the VEMAP data.  The precipitation units are percentage change from the 1961-1990 VEMAP observations.  These calculations were done by first upscaling the VEMAP half degree data to the resolution of the respective GCMs, computing the differences, and then smoothing the differences to create the images below.


CGCM1 Mean Temperature (F) (DJF)


CGCM1 Mean Temperature (F) (JJA)


CGCM1 Mean Temperature (F) (Annual)


CGCM1 Precipitation % (DJF)


CGCM1 Precipitation % (JJA)


CGCM1 Precipitation % (Annual)


HadCM2 Mean Temperature (F) (DJF)


HadCM2 Mean Temperature (F) (JJA)



HadCM2 Mean Temperature (F) (Annual)


HadCM2 Precipitation % (DJF)


HadCM2 Precipitation % (JJA)



HadCM2 Precipitation % (Annual)

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