This report evaluated how changes in climate in the United States would lead to changes by the middle and the end of the current century in annual spending to suppress wildfires on USDA Forest Service (FS) and Department of the Interior (DOI) managed lands.
To do this, researchers developed a two-stage model. In the first stage, we analyzed the historical relationships between area burned on FS and DOI lands and maximum daily temperatures and other variables. In the second stage, we analyzed historical relationships between area burned and suppression spending.
Then, using projections of climate obtained from general circulation models, we projected area burned, and used this projection in our second stage model to project spending on suppression. All spending projections were done with constant 2014 dollars. We made projections for mid-century (2041-2059) and late-century (2081-2099). Uncertainty in the area burned and suppression spending was quantified using Monte Carlo simulation methods, incorporating parametric uncertainty from the two stage models and climate uncertainty from the alternative climate projections.
Results show that median area burned on DOI lands is projected to increase, compared to the amount observed between 1995 and 2013, by 99% by mid-century and by 189% by late-century. For FS lands, the increases are projected to be 123% by mid-century and 221%, respectively. Given such changes in area burned, DOI spending is projected to increase by 45% by mid-century and by 72% by late-century. For the FS, annual spending is projected to rise by 117% and 192%, respectively. Such changes would entail an increase in dollars spent in total across both agencies from a historical average of $1.33 billion to a projected $2.63 billion in mid-century and $3.47 billion by late-century.