Simulating the Earth's climate system is critically dependent on accurate representation of interactions at the air-sea interface where the effects of the ocean are communicated to the atmosphere. A robust manifestation of this ocean-atmosphere interaction is the relationship between sea surface temperature (SST) and surface wind stress. In regions where surface winds blow obliquely across SST fronts (e.g., over the cold tongue in the eastern tropical Pacific), the wind stress is modified by SST-induced changes in the structure and stability of the atmospheric boundary layer. This SST influence is most clearly evident in the wind stress divergence and curl (measures of two components of the total circulation), which have been shown to be linearly related to the downwind and crosswind components of the SST gradient, respectively.
The objective of this study is to investigate this coupling from analyses of the global surface wind stress and SST fields generated by the U.S. climate models that have been developed for the Intergovernmental Panel on Climate Change (IPCC) science assessment. The adequacies of the model representations of this ocean-atmosphere coupling will be assessed by comparing the relationships between the simulated SST and wind stress fields with the relationships deduced from 5 years of satellite measurements of SST and wind stress.
Broader Impacts: If successful, this research should provide better understanding of large-scale ocean-atmosphere interactions and improved estimates of uncertainty in prediction that result from improper representations of those interactions. These outcomes benefit environment managers and decision-makers, and thus, societal activities.
