Development and validation of a leaf wetness duration model using a fuzzy logic system

Abstract

A model to estimate leaf wetness duration (LWD) based on fuzzy logic was developed and validated using hourly weather measurements at 15 sites in the midwestern U.S. from 1997–1999. The Fuzzy model, which required relatively few input variables and simplified calculations compared with physical models, was comparable to sensor measurements in overall accuracy of LWD estimation (<1 h/day error). The Fuzzy model was also more portable than the CART/SLD/Wind model, an empirical model that used the same weather variables, in that the Fuzzy model classified presence or absence of wetness more accurately than the CART/SLD/Wind model at most sites. This suggests that incorporating energy balance principles and empirical computation methods in a fuzzy logic system makes it possible to accurately estimate LWD with a relatively small number of input variables. The accuracy of the Fuzzy model may be improved using correction factors when additional relevant inputs, e.g., solar radiation, become available. Therefore, the Fuzzy model may merit further study to verify this adaptability.