Master of Science
Department or Program
Geography and Environmental Resources
Schoof, Justin T
Atmospheric Oceanic General Circulation Models (AOGCMs) are the primary tools that climate scientists use to investigate past, present and potential future climate. This research paper provides an overview of the strengths and weaknesses of contemporary models across spatial and temporal scales. At large spatial scales, models simulate recognizable patterns of the major modes of climate variability, with a few caveats. Deficiency in reproducing the strength of individual centers of action and detailed temporal characteristics has been noted. The models that best reproduce the spatial pattern are not necessarily the models that simulate the most realistic temporal pattern. Models generally capture observed synoptic scale regimes well, but studies have noted differences in observed and simulated frequencies of specific synoptic patterns as well as differences in seasonality, which could be associated with the links between hemispheric scale climate and synoptic scale circulation. At the regional scale, little literature exists to identify the minimum scale at which GCMs correspond well with observed statistical moments, especially for large ensembles and variables other than temperature and precipitation. Recognition in the climate science community that model performance at small scales is dependent on reliable simulation of processes occurring across scales has led to a new focus on multi-scale assessment of AOGCM fidelity.