What Drives the Increase in Wildfire Risk in the Wildland/Urban Interface?

Post date: Mar 28, 2018 11:19:57 PM

Recently the National Academy of Science published the largest nationwide study ever of wildfire in the WUI, right down to the county level. The authors found the growth of the WUI itself, far more than climate change and weather events, accounts for over 95% of the increase in wildfire risk, whether that growth is measured in number of homes, number of people, or area of the WUI. Obviously, the number of homes in the WUI is strongly correlated with the number of people. Surprisingly, the growth in the area of the WUI is almost entirely due to more homes being built in forests and other areas dominated by natural vegetation. Approximately one in three houses and one tenth of the land area of US are now in the WUI.

Two factors are increasing the risk. With more human activity there are more wildfire ignitions, which account for more than 95% of the ignitions. With more homes and people in the WUI, wildland fires are much harder to fight, since protecting lives and property becomes a higher priority than containing and control the wildland fires themselves.