Re-Evaluation of the Earth’s Surface Energy Balance Using a New Method of Heat Fluxes

Abstract:

The recently proposed and tested model of surface heat fluxes, based on the theory of maximum entropy production (MEP), was used for re-evaluating the global mean annual energy balance over the Earth’s surface. Compared to the commonly used bulk transfer models, the MEP model predicted heat fluxes are constrained by surface radiation fluxes satisfying energy balance and independent of temperature/moisture gradient, wind speed and roughness lengths. The MEP model holds for the entire range of soil moisture from dryness to saturation over land surfaces. It provides the first global maps of water heat fluxes at ocean surfaces as well as at snow/ice covered polar regions. The MEP model is less sensitive to the uncertainties of model input (surface radiation fluxes, temperature and/or humidity) parameters and free of location specific tuning (empirical) parameters. Ten years of earth surface radiation fluxes, surface temperature data products from Clouds and the Earth's Radiant Energy System supplemented (when needed) by the surface specific humidity data from Modern-Era Retrospective analysis for Research and Applications were used to reproduce global annual surface energy budgets. The MEP modeled global annual sensible heat fluxes are in close agreement with both previous studies and ocean content climatology (OHC) data from Woods Hole Oceanographic Institution, while those of latent heat fluxes are significantly lower than previous estimates. The net surface-atmosphere heat exchange according to the MEP model is consistent with the OHC data.