Air Date: Week of June 15, 2012

Elks take refuge in rivers while Montana’s Bitterroot National Forest rages. (Photo: John McColgan with the US Forest Service)

Within a generation climate change will increase the frequency of wild fires across most of the globe. Katharine Hayhoe, an atmospheric scientist at Texas Tech University, used satellite images and climate models to forecast the spread of wildfire. She tells host Bruce Gellerman that hotter temperatures, drought and changing rain patterns will increase wildfire on 80 percent of the planet.

Transcript

GELLERMAN: It's Living on Earth, I'm Bruce Gellerman. Summer isn’t even officially underway and already wildfires have burned tens of thousands of acres across the U.S., displaced hundreds of people from their homes and done millions of dollars in destruction.

[FIRE NEWSREELS: Spreading wildifres and extreme heat, nature is wreaking havoc across the united states. / Firefighters in Colorado and New Mexico are battling massive wildfires that are moving fast. / Extreme fire danger in eastern Arizona and much of New Mexico today, we’re off to a pretty early start here and we didn’t have a whole lot of snow this past winter.]

GELLERMAN: Drier winters and unusually warm summers are what’s in store as climate change alters weather patterns around the world. According to new research, as greenhouse gases warm the earth, we can expect more wildfires in the near future. Katharine Hayhoe, an atmospheric scientist at Texas Tech University, is co-author of the study, which appears in the journal Ecosphere. Professor, welcome to Living on Earth.

HAYHOE: It's a pleasure.

GELLERMAN: So, in order to have a wildfire, you’ve gotta have three ingredients according to your paper, right?

HAYHOE: Yes.

GELLERMAN: You’ve gotta have something to burn…

HAYHOE: That’s right.

GELLERMAN: You’ve gotta have the right atmospheric conditions.

HAYHOE: Yup.

GELLERMAN: And you need a spark.

HAYHOE: (Laughs.) That’s right.

GELLERMAN: So, how does climate change affect those things?

HAYHOE: Well the spark, often these days, comes from people because there are so many of us all across the planet. But the precursor conditions can be affected by climate. Climate change is shifting rainfall patterns around the world - some places are getting wetter and other places are getting drier. We’re also seeing that climate change is increasing our average temperatures, which raises the risk of having those hot, dry conditions that we need for a wildfire to spread.

GELLERMAN: Now the reason that you know that is because you looked at 16 global climate models.

HAYHOE: And we also looked at the whole planet using satellite data that showed us where fires have happened in the past. And what we found was very interesting - in many places, including a lot of the places where we live in North America, we do expect climate change to increase the risk of fire. This is really no surprise: a lot of other studies have found that too. But what we also found was that in some parts of the world, climate change might actually decrease the risk of fires by bringing wetter conditions.

GELLERMAN: I know that in reading your paper, some of it’s kind of counter-intuitive. In some places you get more rain, but you also get more fire.

HAYHOE: I know! And that’s because fire in different parts of the world is controlled by different factors. In some places it’s more temperature sensitive, other places it’s more rainfall sensitive, other times it depends on what’s happening the year before or in a given year.

GELLERMAN: So, for example, you might have more rain in one season, it would grow more stuff, which could burn and then when it gets dry, it’ll burn!

HAYHOE: Exactly! It takes a lot of work to try to unpack all the effects that we can have on the planet.

GELLERMAN: Now, you say North America is going to experience more wildfire in the future.

HAYHOE: Yes, particularly in the West.

GELLERMAN: What about in Europe?

HAYHOE: We see broad patterns of increasing risk of fire across much of the mid-latitudes. In Western Europe, we don’t see it as much as in Eastern Europe and across Russia. And a lot of that is because of the different vegetation patterns as well as the different climate patterns that we have. There’s really no one-size-fits-all answer to how climate change will affect wildfire at the global scale. It really depends very strongly on the specific region.

GELLERMAN: So, in Russia, much of it’s tundra - what are you expecting there? They’ve got huge forests in that region.

HAYHOE: Yes, if you look at the maps of our study, we did project to see increases across much of that area as well. And again, it’s not a surprise: other studies have looked at certain regions and they have found similar results. But our study, what was really unique was, we looked at the whole world in one shot to see what the big picture was.

GELLERMAN: What about the tropics and the subtropics?

HAYHOE: Well, in general, across the tropics, those are the places where we saw the greatest chance of decreasing fire risk.

GELLERMAN: Decreasing?

HAYHOE: Yes. This does not factor in any of our agricultural practices or deforestation or anything like that. That’s only looking at climate as a driver of fire. But because of increases in precipitation, and because much of the fire in those areas is related to precipitation, we expect to see decreases there as a result of climate.

GELLERMAN: Well, the subtropics and the tropics are really important because that’s where we have some of these tremendous rainforests which help moderate climate change.

HAYHOE: Yes! Again, there’s a lot going on that we have to look at when we start to really zoom-in to the regional scale. But what we did that’s really effective for a start was taking the global perspective: what does climate change mean for wildfire across the scale of our planet?

GELLERMAN: So, globally, is the world going to go up in flames, or are we going to be dousing it with more precipitation?

HAYHOE: (Laughs.) No, I don’t think this is going to be the end of the world as we know it.

GELLERMAN: Well, that’s a good thing!

HAYHOE: But what’s happening again is that climate change is interacting with vulnerabilities that we already have, that don’t have anything to do with climate change. It’s just the way that we’ve built our societies, we’ve built our agriculture, our industry, our infrastructure. And what climate change is doing is it’s coming along and it’s interacting with each of those in a unique way for each city, for each state, for each region.

GELLERMAN: Now you’re in Texas, right?

HAYHOE: Yes.

GELLERMAN: Last year Texas had something like 28,000 wildfires, destroying four million acres. I was reading that that’s double the previous record!

HAYHOE: Oh yes! The wildfire came within about two hundred yards of our own place. We went to bed three or four nights in a row convinced that it was going to be burned in the morning.

GELLERMAN: Yeah, I guess Texas Governor Perry asked President Obama to declare 252 out of the 254 counties in Texas as disaster areas.

HAYHOE: I know! Isn’t that incredible?

GELERMAN: So, professor, do you think people connect the dots between what they do now, changing climate, and these wildfires?

HAYHOE: I think that most of us are very aware now that when we burn coal or gas or oil, we are releasing heat trapping gasses into the atmosphere that are building up and as they build up, they are actually altering the climate of our planet. Most of us are aware of this, but it’s really difficult because the size of the problem makes us feel helpless.

GELLERMAN: Well, Professor Hayhoe, thanks a lot.

HAYHOE: It was a pleasure.

[MUSIC: Ernest Ranglin “Ball of Fire” from Below The Bassline (Island Records 1996)]

GELLERMAN: Professor Katharine Hayhoe is an atmospheric scientist at Texas Tech University. You’ll find a link to her study at our website: L-O-E dot ORG.

[MUSIC CONTINUES]

 

Links

Katherine Hayhoe

Climate Change and Disruptions to Global Fire Activity