CMIP5 Global Climate Model Performance Evaluation over the South-Central United States

Future climate change projections from Global Climate Models (GCMs) are the primary drivers of regional downscaling and impacts research – from which relevant information for stakeholders is generated at the regional and local levels. Therefore understanding uncertainties in GCMs is a fundamental necessity if the scientific community is to provide useful and reliable future climate change information that can be utilized by end users and decision makers.      

A performance evaluation was conducted for the Coupled Model Intercomparison Project Phase 5 (CMIP5) GCM ensemble over the south-central United States. A suite of temperature- and precipitation-based statistical metrics were calculated over the modeled historical period and compared to observation-based datasets.  Models were ranked based on individual metrics as well as overall performances. No best model was found for all circumstances but general biases across models were identified.

This assessment may prove useful to regional downscaling and impacts researchers who may be restricted by the total number of GCMs they can utilize. Results from this analysis will be provided as well as a discussion on when it may be useful and appropriate to use.