HR: 0800h
AN: B11D-0774 [Abstracts]
TI: Quantifying the Relative Importance and Potential Interactive Effects of Multiple Indices When Predicting Fire Risk and Severity in the Western US.
AU: * Keyser, A R
EM: akeyser@ucmerced.edu
AF: Sierra Nevada Research Institute, UC Merced
P.O. Box 2039, Merced, CA 95344, United States
AU: Westerling, A
EM: awesterling@ucmerced.edu
AF: Sierra Nevada Research Institute, UC Merced
P.O. Box 2039, Merced, CA 95344, United States
AB:
The national fire plan was implemented after the landmark fire season of 2000 as a response to a perceived
increasing threat of severe wildfires. Subsequently, the Landfire project was initiated to develop a national dataset
comprising vegetation condition, wildland fuels and fire regimes, and ecosystem status to support the national
fire plan. A key product in this dataset to predict areas at risk for severe fires is the fire regime condition class
(FRCC). The FRCC is an index of the degree of departure from the historical fire regime. This departure is a
metric of the difference between current landscape vegetation composition and the range of historical reference
vegetation characteristics; this difference can result from changes in vegetation characteristics and/or the spatial
fire regime. The FRCC index is derived relative to simulated reference conditions, which in turn are based on
Landsum, a landscape fire succession model.
In addition to land management decisions, factors such as nitrogen deposition, ozone and climate affect both
reference and current vegetation characteristics. It is an open question as to whether FRCC is sensitive enough
to capture the full suite of potential effects on fire regimes. We are interested in examining vegetation change (via
FRCC), nitrogen deposition, ozone concentration and climate variability in terms of their utility in predicting spatial
variability in fire regime characteristics. Our analysis includes statistical examination of the multiple effects of
nitrogen deposition, ozone, climate indices, and FRCC on fire frequency, size, and severity in California and the
Western United States. We will assess how these four factors might act alone to influence fire, and their relative
importance as co-determinants of fire risks. Our results will quantify how distinct FRCC is from climate and its
efficacy as a predictor of fire risk and severity. Of particular interest is the extent to which FRCC predicts spatial
variability in fire activity, and the extent to which climate and pollution patterns predict or influence the FRCC.
DE: 0315 Biosphere/atmosphere interactions (0426, 1610)
DE: 0429 Climate dynamics (1620)
DE: 1616 Climate variability (1635, 3305, 3309, 4215, 4513)
DE: 1630 Impacts of global change (1225)
SC: Biogeosciences [B]
MN: 2007 Fall Meeting