Spatial variability of evaporation derived from aircraft and ground‐based data

Ground-based measurements of radiative surface temperature and energy fluxes at sites 26 (8739-ECB) have been used to correct aircraft measurements of radiative surface temperature made over the Institute of Hydrology (IH) site and to estimate the spatial variation of sensible and latent heat fluxes around the site. Over 80 percent of a 5- by 5-km area surrounding the IH site, the sensible heat flux varied between 30 and 90 W m/sq and the evaporation between 4.5 and 5.5. mm/d. Extrapolation to site 16 (4439-ECV) gave reasonable agreement between estimated and measured sensible heat fluxes, after adjustment for the enhanced rate of transfer at site 16 caused by additional roughness and wind speed. 4 refs.