U.S. Joint Fire Science Program


Date of this Version


Document Type



Fire Science Brief, Issue 8, May 2008


US government work.


Climate is a vital force shaping much of life on Earth. People have long suspected a link between climate and susceptibility of forests to fire. But measuring such a relationship has been challenging without tools capable of taking into account climate, forest structure through space and time, and other variables. Managers and planners who make decisions to maintain forest health need an accurate understanding of how climate is linked to fire regimes, as well as tools to help them do it. Such tools would take complex information and allow it to be accessed in a straightforward and effective way. Don McKenzie is a research ecologist with the USDA Forest Service at the Pacific Northwest Research Station. He and a team of scientists linked two types of data from sites across eastern Washington: fire scar records (the Eastern Washington Fire History dataset) and tree ring chronology data that show the effect of climate on tree growth. By uniting these two datasets, the scientists looked at how climate has affected fire history. They found an undeniable relationship between fire and climate, including a link to short and longer term periodicity of fire regime with the El Niño Southern Oscillation and the Pacific Decadal Oscillation. They also found that the 20th century era of fire exclusion “decoupled” the strong link between fire and climate. They expect global climate change to be a major player in the future with surprises in store.