Evaporation and storage of intercepted rain analysed by comparing two models applied to a boreal forest

Rainfall and throughfall were measured during the summer of 1995. Rainfall interception is often simulated by a version of the well-known Rutter-Gash analytical model. In this study this model was compared to a model based on an exponential saturation equation. The concept of the 'minimum method' fo r deriving canopy storage capacity and free throughfall coefficient by the Leyton-analysis, is compared to the concept of maximum storage capacity by reversing the models. Measured evaporation rate during rain events was foun d to be lower than simulated by the Penman equation using different known f ormulations for aerodynamic resistance. The concept of a high internal cano py resistance and decoupling of the canopy from the atmosphere should be an alysed further in order to explain low evaporation during rainfall. (C) 199 9 Elsevier Science B.V. All rights reserved.