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Study: Human Activity To Blame For 90% Of Wildfires In California

Study: Human Activity To Blame For 90% Of Wildfires In California
Study: Human Activity To Blame For 90% Of Wildfires In California GUEST: Michael Mann, assistant professor of geography, George Washington University

At this time just two years ago San Diego is recuperating from an outbreak of devastating wildfires, the May 2014 wildfires for the largest and see which fire in 2007, already this year the U.S. Forest Service says five times more acres have burned at this time last year San Diego Fire Chief Brian Tennessee said yesterday that he is concerned about the tall fit club of grass around the region. In the fire star in the grass a move quickly with or without when and blow into the dryer heavier education. That dry legislation is what is going to cause the largest problem. The threat of fire is increasing In your research paper warns that is not the only reason. It turns out that more than 90% of wildfires in California are caused by human activity. Joining me is Michael Mann assistant assessor of geography at George Washington University, author of the paper on the effects of human activity and climate change on fire activity in California. Michael welcome to the program. Wiki for having me. What you mean by human activity. What I am talking about is the location and density of residential housing communities. In much of California this includes lots of low density residential development and sort of a wildland urban edge of urban communities. Is that expand to electrical poles that get blown down and spark fires during Santa Ana conditions? Yes with residential development we get a great deal of infrastructure that comes along with it. A lot of human activity, that includes electrical poles, to campfires, to construction equipment that can ignite a fire easily. Do you recommend that the communities that building out into the back country or should they do it in a better way? That is a complex question that really I can speak limited to. But, I think that we can say that the expansive low density housing development that has been rampant in California increases the risks of wildfires to the individuals in the houses as well as the communities that they belong to. On the face of it it is not surprising that humans are the ignition source of most wildfires, Smokey the bear told us that years ago, but do you think the message is being downplayed now because of the emphasis on drought and I'm it change? I do not think it is being downplayed, I think it is lost in the message I think the decisions that we make today about the location of housing and the way that we zone our buildings these have long-term impacts on the future. Do these factor in human activity? To an extent they have. But we found is that 50% of changes in wildfire patterns over the last 25 years were determined by the location and intensity of residential communities. The modeling that you are talking about is the kind of modeling that you and a team of researchers have done that it does take both climate change and human behavior into account what does the model tell you about the threat of wildfires in California # But we expect is an increase in the acreage burned over the next 25 years. Our model is relatively conservative to most but we are expecting an increase between 3 to 5%. However, what I think is missing is the cost of the wired fires -- the cost of the wildfires should be expected to increase significantly. If we have an increase in fires due to climate change where you have dryer and hotter conditions and you have a continued rapid expansion of residential growth into the fire prone areas cut you are going to have a very dangerous mix of those two factors. One of the recommendations in your report is rethinking the effectiveness of our current firefighting approach. How could we fight wildfires differently question why -- Looking at it more comprehensively, as a package, of tools. A lot of resources have been diverted into wildfire suppression which is fine, but that is sort of a react of response to wildfire. There has not been enough effort on proactive approaches where you are doing controlled burns, you are reducing fuel loads ahead of time, you are doing more outreach to households on how they can maintain and protect their own communities. I know you said it is complex, but is there a way that you see in this report or in your studies of this, that expanded development can happen in a way that makes it less likely that human activity will spark a wildfire? I think we can reduce the risks to the houses that are being built that any time you introduce additional humans into a landscape you are going to introduce additional aid missions. If that is coupled with extra dry conditions in California, that will mean more wildfire So it would seem to me that one of the things that people could take from this research is that cities like San Diego should really consider long and hard about where new developments are built, is that right? Absolutely. I think the citizens we have very little control over the policies that shape climate change. In the case of wildfires individuals in the local communities have a lot of leverage to control the future of wildfire risks. Back how would you like to see the results of the study being used? I would like to see policymakers be more proactive in their approach to wildfire management and I would like to see local governments rethink the way they plan and communities the communities with long-term risks of what they face. I've been speaking with Michael Mann this paper on human activity and change on fire activity appears internal +1. Thank you so much for your time Michael. Thank you very much.

In its latest forecast, the U.S. Forest Service this week said Southern California is “particularly vulnerable” to wildfire given the ongoing drought and the 40 million dead trees that could fuel fires. The agency said that five times more acres have burned in 2016 compared to the same time last year.

But a new study, published in the scientific journal PLOS One, suggests it’s not just the weather that's driving wildfires.


Researchers at the George Washington University found human activity — everything from cigarette litter to toppled power poles — is as much to blame for how often and where wildfires occur.

According to the study, people are responsible for igniting about 90 percent of the wildfires in California.

"Half of the changes in wildfire patterns over the last 25 years were determined by the location and the density of residential communities," Michael Mann, assistant professor of geography at the George Washington University and lead author of the study, told KPBS Midday Edition on Thursday.

He said that policy makers need to take a more proactive approach to wildfire management, and that local governments should rethink the way they plan communities.

"The decisions that we make today about the location of housing, the way that we zone our buildings, building codes — these all have really long-term impacts on the risks that we face in the future," Mann said.

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