Wednesday, 19 November 2003: 2:45 PM
A comparison of 3 models of 1-hr time lag fuel moisture in Hawaii
Fosberg developed a model of moisture diffusion in wood that is currently used in the National Fire Danger Rating System to predict fine fuel moisture. Nelson recently developed a fuel moisture model that includes functions for both heat and moisture transfer. Fuel moisture samples were collected in Hawaii hourly for up to 96 hours for an herbaceous plant near mean sea level (MSL), pine needles and eucalyptus leaves at 200 m MSL, pine needles at 1500 m MSL, and a native grass at 2500 m MSL. Weather data were collected every five minutes. Weather variables necessary to predict fuel moisture were also predicted using a mesoscale model. Fuel moisture predictions from each physical model are compared with the observed fuel moistures. Predictions from a time series model using equilibrium moisture content are also presented. Results of the comparisons will be presented and implications for application of fire danger rating in Hawaii are discussed.