quote | Computational modeling and laboratory and field experiments that describe the heat transfer required for ignition have shown that the large flames of burning shrubs and tree canopies (crown fires) must be within one hundred feet to ignite a home’s wood exterior. ... This [photo] is a typical WUI [Wildland-Urban Interface] fire disaster scene with unconsumed and green vegetation surrounding burned structures (Grass Valley Fire). The homes ignited from low-intensity surface fires and firebrands (lofted burning embers). The trees then caught fire from the burning homes. The totality of destruction is due to the lack of fire suppression rather than the intensity of the initial ignition sources. ... Thus, given ignition-resistant homes, extreme wildfires can spread to residential areas without incurring WUI fire disasters. ... Preventing wildfire disasters thus means fire agencies helping property owners mitigate the vulnerability of their structures. |