Understanding Regional Climate Variations and Trends over North America (Invited)

Predictability of regional climate changes over the next several decades will depend crucially on the mechanisms that produce regional differences in the responses to climate forcings as well as on the ability of models to correctly simulate the key physical processes. This presentation summarizes findings from a recent USGCRP synthesis and assessment report and subsequent studies aimed at attributing the causes of patterns of recent North American climate change. First, regional differences are identified in climate variations and trends across North America over the past several decades. Climate model simulations are then employed to help identify the causes of the regional differences. Patterns of sea surface temperature changes are found to play an important role in explaining past North American regional climate changes. The results suggest that the ability to anticipate future regional climate changes across North America will depend strongly on the ability of models to predict future changes in sea surface temperature patterns.