SCALING OF LAND ATMOSPHERE INTERACTIONS - AN ATMOSPHERIC MODELING PERSPECTIVE

Investigations of the impact of the ground surface on energy and mass fluxes in the atmosphere as well as on the dynamic response of the atm osphere at different scales are reviewed to emphasize the requirements for hydrological schemes for atmospheric models. Based on these inves tigations, a discussion on the scaling of the most important land proc esses and characteristics, from an atmospheric modelling perspective, is provided. It appears that because of the strong, non-linear respons e of the atmosphere to the spatial variability of land-surface charact eristics, the scaling of hydrological processes and parameters is not linear. This implies that appropriate hydrological schemes for atmosph eric models need to provide higher statistical moments and characteris tic length scales of the spatial distribution of water availability fo r evapotranspiration.