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Updated 12 October, 2003

US National Assessment of
the Potential Consequences
of Climate Variability and Change
Model Intercomparisons




The figures below are decadal means plotted at the centers of the respective decades (e.g. 1860-1869 is plotted at 1865).  The anomalies are all differences from the decade 1961-1990.  The mean temperature represents the mean screen temperature, and the precipitation represents the total precipitation.  The U.S. anomalies are calculated for a region covering the conterminous U.S. only.  The model scenarios for all but the NCAR CSM and DOE PCM are 1% increase in equivalent CO2 (ECHAM4/OPCY3 is is92a) with is92a sulfate aerosols.  The DOE PCM and NCAR CSM bau use an approximation to the is92a greenhouse gases, but with multiple greenhouse gases, and with a much lower sulfate scenario.  Both DOE PCM and NCAR CSM stabilization scenarios represent stabilization at 550 ppmv CO2. 

The GFDL model is the R30 version.  Note that ECHAM4/OPCY3 was only run to the year 2049.  The two models in bold, HadCM2 and CGCM1, represent the primary models used by the national assessment and are taken from the first ensemble of each.


Global Temperature

U.S. Temperature


Global Precipitation

U.S. Precipitation

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