LAND-SURFACE WATER-VAPOR AND SENSIBLE HEAT-FLUX - SPATIAL VARIABILITY, HOMOGENEITY, AND MEASUREMENT SCALES

Available methods to determine the sensible and latent heat fluxes fro m the Earth's land surfaces are still relatively imprecise; this is du e primarily to the inherent irregularity of the turbulent transport me chanisms and also to the pronounced variability of most natural land s urfaces. While great progress has, been made in the study of turbulenc e, until recently, surface variability has received relatively little attention in this context. Some thoughts are provided on approaching t his issue by focusing on the stochastic structure of the land surface within the framework of homogeneous, i.e., stationary, random function s. In addition, suggestions are made regarding the likely applicabilit y of classical concepts by relating the relevant scales of surface var iability structure to those characterizing turbulent transport in the atmospheric boundary layer.