Optical-microwave data synergism to provide parameters required as inputs by surface energy balance models

The role of remote sensing inputs in driving surface energy balance models (SEBM) is highly conditioned by the availability of appropriate data in terms of spatial and temporal resolutions, and covering the spectral ranges where useful information can be extracted. Classical SEBM use mainly optical inputs from present operational satellites, but future systems will provide new kind of data, which should be incorporated in new approaches to modeling surface energy fluxes. The main objective of this work is to assess the convenience and/or difficulties in the synergistic use of optical (TM, TMS and AVIRIS) and microwave (AirSAR) data, to estimate input parameters required by advanced SEBM. Apart from the derivation of surface parameters, useful for SEBM, from both optical and microwave data, AVIRIS data allow derivation of some atmospheric inputs, like two-dimensional atmospheric water vapor maps, which can be also used to derive surface temperature from simultaneous aircraft thermal-infrared-data. The EFEDA experiment carried out in Central Spain in June 1991 provided availability of remote sensing data, together with ground and atmospheric measurements. Fluxes were also measured, on the ground and from aircrafts, at different scales. In estimating the inputs parameters from the remote sensing data, the accuracy of each parameter and its spatial and temporal resolutions are determined by the requirement and sensitivity of SEBM for each parameter