Incident solar radiation simulated by general circulation models for the southwestern United States

Estimates of incident solar radiation for the southwestern United States from 4 general circulation models (GCMs) are evaluated by comparison to observed values. Results indicate that GCMs reliably simulate the annual solar cycle, but generally underestimate incident solar radiation for the southwestern United States. For climatic conditions resulting from a doubling of atmospheric carbon dioxide, the 4 GCMs evaluated in this study estimate increases of 1 to 3% of mean annual incident solar radiation simulated for current climatic conditions.