A new model for the prediction of rainfall interception in forest canopies

A new model without empirical parameters for the prediction of rainfall interception in forests is derived. All the parameters used in the model, including canopy storage capacity, canopy dryness index, canopy closure, and evaporation rate from the wet canopy, have specific physical meanings. The model can be run on an hourly, daily or event basis according to the availability of meteorological data. The relationships between the new model and some other models are also discussed. The model is successfully applied to the cypress wetlands and slash pine uplands in the Florida flatwoods and is compared with other models using data from the literature. The predicted weekly rainfall interception explains 89% of the variation in interception measured at six cypress wetlands and pine uplands.