| A Surface Energy Balance System (SEBS) is
proposed for the estimation of atmospheric turbulent fluxes and evaporative
fraction using satellite earth observation data, in combination with
meteorological information at proper scales. SEBS consists of: a set of tools
for the determination of the land surface physical parameters, such as albedo,
emissivity, temperature, vegetation coverage etc., from spectral reflectance and
radiance measurements; a model for the determination of the roughness length for
heat transfer; and a new formulation for the determination of the evaporative
fraction on the basis of energy balance at limiting cases. Four experimental
data sets are used to assess the reliabilities of SEBS. Based on these case
studies, SEBS has proven to be capable to estimate turbulent heat fluxes and
evaporative fraction at various scales with acceptable accuracy. The
uncertainties in the estimated heat fluxes are comparable to in-situ measurement
uncertainties.
Keywords: Surface energy balance, turbulent heat flux, evaporation, remote sensing |