Obtaining surface energy fluxes from remotely sensed data

Land surface fluxes have been estimated from remotely sensed data at high pixel resolutions (approximately 60 m) with reasonable accuracy when compared to ground measurements (French et al., 2003; Kustas and Norman, 1999). The remote sensing input used to model land surface fluxes may consist of land surface temperature and a vegetation index. Remotely sensed land surface temperature estimates are strongly affected by atmospheric effects and the generally unknown land surface emissivity. These effects mean that land surface temperature estimates can vary by 1–3 degrees. Similarly, the visible and infra-red bands that are used to calculate vegetation indices are affected by the atmosphere and radiance data should be corrected before calculating such indices.