APPLICATION OF SATELLITE REMOTE SENSING TO ESTIMATE AREAL EVAPOTRANSPIRATION OVER A WATERSHED
Résumé
A method for estimating areal evapotranspiration by using synoptical weather data and satellite imagery is presented. Recent studies have shown that if atmospheric and surface parameters are known, the energy and hydraulic budgets at the soil/vegetation]atmosphere interface can be simulated. Then, soil temperature estimated by thermal infrared remote sensing can be used to derive the energy fluxes as far as they are the equilibrium term of the energy budget. This methodology has been applied in southwestern Finland over the Eurajoki River basin. The model was first calibrated with ground measurements and satellite data. The NDVI and the surface temperature estimated from NOAA/AVHRR data have been used to calibrate the leaf area index and the minimum resistance to evapotranspiration. The different land use classes over the river basin were interpreted from LANDSAT/TM images, and the model was then run over the whole month of July 1988 for all the most important soil and vegetation types of the river basin. Finally, the total derived evaporation was compared with the one estimated by a water balance method applied over the month of July.
Domaines
Sciences de l'environnementOrigine | Publication financée par une institution |
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