Can Surface Energy Budgets be Balanced on Continental Scales Using Observational Datasets?

Wednesday, 17 December 2014: 4:24 PM
Tristan S L'Ecuyer, University of Wisconsin Madison, Madison, WI, United States
Recent efforts to balance the surface energy budget on global and regional scales using the latest observational datasets result in unrealistically large imbalances between net radiation into the surface and corresponding turbulent heat fluxes, particularly over the global oceans. These imbalances can be traced, in part, to the fact that component fluxes tend to be estimated independently with no explicit reliance on closure constraints. Arguments have been made in favor of reducing downwelling radiation or increasing global precipitation to resolve these imbalances and satisfy constraints imposed by recent ocean heat content measurements. However, since all estimates of the energy fluxes contributing to the global energy balance have associated uncertainties, it is likely that all terms bear some responsibility for the imbalances. This presentation will document new estimates of continental-scale surface energy budgets and their seasonal cycles obtained using a new objective approach for reintroducing energy balance constraints on observational flux datasets. The method adjusts all component fluxes based on their relative uncertainties and provides explicit metrics for assessing the extent to which global and regional energy and water cycles can be simultaneously balanced within assumed error bounds. The behavior of fluxes in land and oceanic regions will be contrasted and regions that require flux adjustments in excess of assumed uncertainties will be identified.