Adapt to more wildfire in western North American forests as climate changes, Schoennagel et al. 2017

Wildfires in the West have become larger and more frequent over the past three decades (globally, the length of the fire season increased by 19% from 1979 to 2013) and this trend will continue with global warming. Typical fire prevention strategy, centering on fuel reduction and fire suppression, has proved inadequate. Instead, society must accept the inevitability of fires and reorganize itself accordingly, according to this study. Specifically, an adaptive resilience approach would mean:

(i) recognizing that fuels reduction cannot alter regional wildfire trends; (ii) targeting fuels reduction to increase adaptation by some ecosystems and residential communities to more frequent fire; (iii) actively managing more wild and prescribed fires with a range of severities; and (iv) incentivizing and planning residential development to withstand inevitable wildfire [Schoennagel 2017: 4582].

Between 1990 and 2010, almost 2 million homes were added in the 11 states of the western United States, increasing the WUI [wild-urban interface] area by 24%. Currently, most homes in the WUI are in California (4.5 million), Arizona (1.4 million), and Washington (1 million). Since 1990, the average annual number of structures lost to wildfire has increased by 300%, with a significant step up since 2000. About 15% of the area burned in the western United States since 2000 was within the WUI, including a 2.4-km community protection zone, with the largest proportion of wildfires burning in the WUI zone in California (35%), Colorado (30%), and Washington (24%). Additionally, almost 900,000 residential properties in the western United States, representing a total property value more than $237 billion, are currently at high risk of wildfire damage. Because of the people and property values at risk, WUI fires fundamentally change the tactics and cost of fire suppression as compared with fighting remote fires and account for as much as 95% of suppression costs [Schoennagel 2017: 4583].

There often is a lack of political will to implement policies that incur short-term costs despite their long-term value or to change long-standing policies that are ineffective. For example, few jurisdictions have the will or means to restrict further residential development in the WUI, although modifying and curtailing residential growth in fire-prone lands now would reduce the costs and risks from wildfire in the long term. [Schoennagel 2017: 4585].