Hydrology and Earth System Sciences www.hydrol-earth-syst-sci.net 1027-5606 1607-7938 13 6 2009 10.5194/hess-13-749-2009 http://www.hydrol-earth-syst-sci.net/13/749/2009/ http://www.hydrol-earth-syst-sci.net/13/749/2009/hess-13-749-2009.html http://www.hydrol-earth-syst-sci.net/13/749/2009/hess-13-749-2009.pdf 749 758 2009-06-12 A Bayesian approach to estimate sensible and latent heat over vegetated land surface C. van der Tol tol@itc.nl S. van der Tol A. Verhoef B. Su J. Timmermans C. Houldcroft A. Gieske ITC International Institute for Geo-Information Science and Earth Observation Hengelosestraat 99, P. O. Box 6, 7500 AA Enschede, The Netherlands Delft University of Technology, Faculty of Electrical Engineering, Mekelweg 4, 2628 CD Delft, The Netherlands The University of Reading, Department of Soil Science, School of Human and Environmental Sciences, Reading RG6 6DW, UK Sensible and latent heat fluxes are often calculated from bulk transfer equations combined with the energy balance. For spatial estimates of these fluxes, a combination of remotely sensed and standard meteorological data from weather stations is used. The success of this approach depends on the accuracy of the input data and on the accuracy of two variables in particular: aerodynamic and surface conductance. This paper presents a Bayesian approach to improve estimates of sensible and latent heat fluxes by using a priori estimates of aerodynamic and surface conductance alongside remote measurements of surface temperature. 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