Page 90 – COMPLAINT
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Thomas, Coon, Newton & Frost
820 SW 2nd Ave., Ste. 200
Portland, OR 97204
Phone - (503) 228-5222
Fax - (503) 273-9175
that is attributable to fossil fuel induced ACC.
259.
Anthropogenic climate change, induced by the burning of fossil fuels, has caused and
See Dennison et al. (2014) (increased Western wildfire attributed in part to warmer and drier
summer conditions (drought severity). For all ecoregions combined, the number of large fires
increased at a rate of seven fires per year, while total fire area increased at a rate of 355 km
2
per
year.”); Westerling (2016) (reaffirmed the tight association between wildfire activity and the
relatively high cumulative warm-season actual evapotranspiration and early spring snow melt.
Notably, there was a +1000% increase in wildfire activity from 2003-2012 and the increase was
attributed to spring and summer temperature increases.); Abatzoglou and Williams (2016)
(“anthropogenic increases in temperature and vapor pressure deficit significantly enhanced fuel
aridity across western forests during 2000–2015, contributing to 75% more forested area
experiencing high fire-season fuel aridity and an average of 9 additional days per year of high fire
potential. ACC accounted for
55% of observed increases in fuel aridity and wildfire potential in
recent decades.”); Holden et al. 2017 (declines in summer precipitation and rain days associated
with GHG increases are the primary driver of increases in wildfire area in the West.); Abatzoglou
et al. (2021) (“the 2020 Labor Day fires in Oregon exceeded the area burned in any single year for
at least the past 120 years, contributing to hazardous air quality and massive smoke plumes.
Unusually warm conditions with limited precipitation occurred in the 60-days prior to the fires.
Exceptionally strong winds and dry air drove rapid rates of fire spread. The concurrence of these
drivers created conditions unmatched in the observational record.”); Mass et al. 2021 (“the Labor
Day fires of 2020 were driven by strong … highly unusual winds. Wildfires produced dense smoke
that initially moved westward over the Willamette Valley and eventually covered the entire region.
Air quality rapidly degraded to hazardous levels, representing the worst levels in recent decades.”);
Hawkins et al. (2021) (“ACC factors (fuel aridity, warmer temperatures during dry wind events)
increased fuel aridity and likelihood of extreme fire weather by 40% in northern California and
Oregon.”); Dahl et al. (2023) (linked increases in burned forest area across the West and
southwestern Canada to the vapor pressure deficit, meaning drier atmospheric conditions produced
drought-stressed plants and soils that readily burned. The study used a robust global energy balance
carbon-cycle model and a suite of downscaled climate models to “attribute emissions to vapor
pressure deficit from 1901–2021 and cumulative forest fire area from 1986–2021. Emissions were
responsible for 48% of long-term rise in vapor pressure deficit and, correspondingly, 37% of the
cumulative area burned. Emissions also contributed to nearly half the increase in drought- and fire-
danger since 1901.”); MacDonald et al. 2023 (Synthesizing the literature on climate-wildfire
attribution studies finding that there was a “striking increase in annual area burned in the West
related to increasing temperatures and the atmospheric vapor pressure deficit. ACC was the main