Hydrology and Earth System Sciences www.hydrol-earth-syst-sci.net 1027-5606 1607-7938 13 11 2009 10.5194/hess-13-2179-2009 http://www.hydrol-earth-syst-sci.net/13/2179/2009/ http://www.hydrol-earth-syst-sci.net/13/2179/2009/hess-13-2179-2009.html http://www.hydrol-earth-syst-sci.net/13/2179/2009/hess-13-2179-2009.pdf 2179 2190 2009-11-12 Footprint issues in scintillometry over heterogeneous landscapes W. J. Timmermans timmermans@itc.nl Z. Su A. Olioso International Institute for Geo-information Sciences and Earth Observation, Dept. of Water Resources, P.O. Box 6, 7500 AA, Enschede, The Netherlands UMR 1114 INRA-UAPV Environnement Méditerranéens et Modélisation des AgroHydrosystèmes (EMMAH), Site Agroparc, Domaine St. Paul 84914 Avignon Cedex 9, France Scintillometry is widely recognized as a potential tool for obtaining spatially aggregated sensible heat fluxes at regional scales. Although many investigations have been made over contrasting component surfaces, few aggregation schemes consider footprint contributions. In this paper, an approach is presented to infer average sensible heat flux over a very heterogeneous landscape by using a large aperture scintillometer. The methodology is demonstrated on simulated data and tested on a time series of measurements obtained during the SPARC2004 experiment in Barrax, Spain. Results show that the two-dimensional footprint approach yields more accurate results of aggregated sensible heat flux than traditional methods. Avissar, R. and Pielke, R. A.: A parameterization of heterogeneous land surfaces for atmospheric numerical models and its impact on regional meteorology, Mon. Weather Rev., 117, 2113–2136, 1989. Brutsaert, W.: Evaporation into the atmosphere, Reidel, Dordrecht, The Netherlands, 299 pp., 1982. 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