HR: 0800h
AN: B11D-0778 [Abstracts]
TI: A Calibration of Temperature and Fire Frequency
AU: * Guyette, R P
EM: guyetter@missouri.edu
AF: University of Missouri, 203 ABNR Building, Columbia, MO 65211, United States
AU: Stambaugh, M C
EM: stambaughm@missouri.edu
AF: University of Missouri, 203 ABNR Building, Columbia, MO 65211, United States
AU: Dey, D C
EM: ddey@fs.fed.us
AF: Northern Research Station USFS
Northern Research Stat. USFS, 202 ABNR Building, Columbia, MO 65211, United States
AB:
A predictive model of fire frequency in North America using climate and human population density shows promise
in estimating the importance of fire at broad temporal and spatial scales. Over 5 thousand fire scars from 120
sites and nine forest ecosystems were used to empirically derive and test a fire interval regression model. Three
predictor variables were selected: a proxy of annual mean maximum temperature, annual precipitation, and
human population density. The model was calibrated using mean fire intervals that document the presence of
fire in a 1 to 3 km2 area during the two centuries prior to Euro-American settlement. This period allows for a
more accurate calibration of temperature and fire frequency because of the reduced effects of land use, fire
suppression, and other technological factors on fire events. Fifty five percent of the variance in mean fire intervals
was explained by annual mean maximum temperature, 10 percent by annual precipitation, and an additional 11
percent by human population density (model r-square = 0.76). Although coarse (256 km2 cells), mean fire
interval estimates provide a empirically derived and plausible depiction of the continental variability in historic U.S.
fire frequency. Based on the regression diagnostics and spatial patterning in fire frequencies it is apparent that
temperature is an important factor to U.S. fire regimes. We discuss the role of temperature as a 'master' variable
for understanding multiple fire regime characteristics such as the rate of fuel combustion (the Arrhenius
equation), the length of the fire season, and the broad scale variability of fire events. Modeling limitations,
potential, and fire severity will be discussed.
UR: http://www.missouri.edu/~guyetter
DE: 0439 Ecosystems, structure and dynamics (4815)
DE: 0460 Marine systems (4800)
DE: 0473 Paleoclimatology and paleoceanography (3344, 4900)
DE: 4920 Dendrochronology
DE: 9350 North America
SC: Biogeosciences [B]
MN: 2007 Fall Meeting