ESTIMATION OF LAND-SURFACE PARAMETERS USING SATELLITE DATA

Surface observations and NOAA advanced very high resolution radiometer (AVHRR) satellite data are combined to provide area-averaged values o f albedo, canopy resistance, leaf area index and fractional vegetation cover. Albedo, fractional vegetation cover and leaf area index are de rived from the reflectance of the visible and infra-red NOAA AVHRR cha nnels. Canopy resistance is estimated by closing the surface energy ba lance equation using the surface infra-red temperature and the normali zed difference vegetation index. These land surface parameters are eva luated against independent measurements and used as input into a numer ical model to simulate the energy exchange between the surface and the overlying atmosphere. Simulation results are validated against detail ed aircraft observations undertaken in south-western Australia over bo th natural and agricultural vegetation.