The number of fire events is constrained to one per year, and simulated
fire effects are applied during the month following that of the simulated
fire event.
Fire effects include the consumption (i.e., volatilization of both C
and N components) of aboveground live and dead biomass, and the
fire-induced mortality of live biomass implemented as increases in
live-to-dead pool turnover rates. The percentage consumption of
live grass and dead biomass pools (i.e., litter, standing dead, fine
and coarse wood debris) is a function of the moisture content and
surface/volume ratio of each fuel class. Fire-induced mortality of
aboveground, live woody components (live leaves, fine and coarse
live wood, and live roots) occurs as a function of simulated crown
kill and the lethal heating of stem cambium. If the canopy is
completely killed in a simulated crown fire, the live leaves and fine
branches are totally consumed and all the coarse live wood is
transferred to the coarse woody debris pool. Otherwise, live leaves
and fine branches die in proportion to crown kill, live coarse wood
and live roots die in proportion to mortality, and the killed
fractions are transferred to the dead pools.
Simulated fire area is reported for the conterminous U.S. on the MAPSS web site as Fire Risk Forecasts (option located on the lower left corner of the page) updated monthly.
