Wildfires worse due to global warming, studies say

May 18, 2014 by Seth Borenstein
A helicopter transporting water flies over trees during a wildfire Thursday, May 15, 2014, in Escondido, Calif. One of the nine fires burning in San Diego County suddenly flared Thursday afternoon and burned close to homes, trigging thousands of new evacuation orders.(AP Photo/Gregory Bull)

The devastating wildfires scorching Southern California offer a glimpse of a warmer and more fiery future, according to scientists and federal and international reports.

In the past three months, at least three different studies and reports have warned that wildfires are getting bigger, that man-made is to blame, and it's only going to get worse with more fires starting earlier in the year. While scientists are reluctant to blame global warming for any specific fire, they have been warning for years about how it will lead to more fires and earlier fire seasons.

"The fires in California and here in Arizona are a clear example of what happens as the Earth warms, particularly as the West warms, and the warming caused by humans is making fire season longer and longer with each decade," said University of Arizona geoscientist Jonathan Overpeck. "It's certainly an example of what we'll see more of in the future."

Since 1984, the area burned by the West's largest wildfires—those of more than 1,000 acres (400 hectares)—have increased by about 87,700 acres (35,500 hectares) a year, according to an April study in the journal Geophysical Research Letters. And the areas where fire has been increasing the most are areas where has been worsening and "that certainly points to climate being a major contributor," the study's main author Philip Dennison of the University of Utah said Friday.

The top five years with the most acres burned have all happened in the last decade, according to federal records. From 2010-2013, about 6.4 million acres (2.6 million hectares) a year burned on average; in the 1980s it was 2.9 million acres (1.17 million hectares) a year.

"We are going to see increased fire activity all across the West as the climate warms," Dennison said.

That was one of a dozen "key messages" in the 841-page National Climate Assessment released by the federal government earlier this month. It mentioned wildfires 200 times.

"Increased warming, drought and insect outbreaks, all caused by or linked to climate change have increased wildfires and impacts to people and ecosystems in the Southwest," the federal report said. "Fire models project more wildfire and increased risks to communities across extensive areas."

Likewise, the Nobel Prize-winning Intergovernmental Panel on Climate Change noted in March that wildfires are on the rise in the western U.S., have killed 103 Americans in 30 years, and will likely get worse.

The immediate cause of the fires can be anything from lightning to arson; the first of the San Diego area fires, which destroyed at least eight houses, an 18-unit condominium complex and two businesses, seemed to start from sparks from faulty construction equipment working on a graded field, said California Department of Forestry and Fire Protection spokeswoman Lynne Tolmachoff.

But the California fires are fueled by three major ingredients: drought, heat and winds. California and Arizona have had their hottest first four months of the year on record, according to National Weather Service records. Parts of Southern California broke records Thursday, racing past 100 degrees Fahrenheit (38 degrees Celsius). For the past two weeks the entire state of California has been in a severe or worse drought, up from 46 percent a year ago, according to the U.S. drought monitor.

"With the drought this year, we're certainly going to see increased frequency of this type of event," Dennison said. "Because of the drought the fuels (dry plants and trees) are very susceptible to burning."

Another study last month in Geophysical Research Letters linked the ongoing drought to man-made climate change. Other scientists say that is not yet proven.

Scientists will have to do a lot of time-consuming computer simulations before they can officially link the drought to climate change. But Overpeck said what is clear is that it's not just a drought, but "a hot drought," which is more connected to man-made warming.

The other factor is the unusual early season Santa Ana winds, whose strength is a key factor in whipping the flames. So far, scientists haven't connected early Santa Ana to climate change, Dennison said.

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User comments : 9

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210
3 / 5 (6) May 18, 2014
WHA!!!?
This is the most civil, intelligent -gasp- well-mannered discourse over this matter of Global Climate change I have ever seen! NOT ONE evil word, no harsh contempt or vilifications, no insults, no HATE....no, no.....NOTHING!
To think I LIVED TO see this day....please....give me a moment of silence in which to shed a tear having seen humanity ....has either EVOLVED beyond petty hate, OR....every one who has net access is dead...a moment...please.

word-to-ya-muthas
GuruShabu
2 / 5 (12) May 18, 2014
The same BS as usual...probably the floods in Serbia, the hijack in Nigeria, the house bubble should be related to the HGW.
These guys do not have any commitment but to brainwash this religion into people by endlessly repeating this preach.
The head of IPCC was banned 10 years ago for cooking data and is back with all his dignity to the pulpit.
Noumenon
1.7 / 5 (11) May 18, 2014
There is absolutely no credible scientific justification to link wildfire severity to a 1*c increase in GLOBAL temperatures as compared to 100 years ago. It is an abject fraud to do so, and is why no one with any sense will take these alarmist clowns seriously. They're hurtng their own cause.

The minute a critique mentions the prior 17 years pause in global temp rising, these very same charlatans claim 'it's not enough trend',... but 'yea the wildfires are worse because of AGW'. Yet, dimwits wonder why there are "deniers".
Egleton
3.9 / 5 (7) May 18, 2014
You guys have a manual to work out of, right?
Get paid by the line?
Couldn't give a flying fig about the results so long as the money is in the bank.
Then again, you might just be very intelligent bots, triggered off by certain words with very little human input. I wonder how many bots are controlled by one human? Sent to muddy the water.

Where is me mate Nick? Wazzup Nick-battery flat?
ryggesogn2
1.8 / 5 (10) May 18, 2014
"Conditions leading up to this 1889 fire event included a much longer and more severe annual drought than usual, with rains largely ceasing in March and less than 1 cm of precipitation being recorded for the 5½ months prior (records from the National Archives). This was coupled with multiple katabatic wind events (known as "northers" or Santa Anas) that month, one of which occurred about 10 days prior and likely added to the dryness of fuels. Temperatures during the week prior remained high and were coupled with several severe fires in San Diego County in which "at least 10,000 acres (40 km2) have burned over, a dwelling house consumed and other property destroyed"[1]"
http://en.wikiped..._of_1889
tdw
1.5 / 5 (8) May 19, 2014
"In the past three months, at least three different studies and reports have warned that wildfires are getting bigger, that man-made climate change is to blame, and it's only going to get worse with more fires starting earlier in the year. While scientists are reluctant to blame global warming for any specific fire, they have been warning for years about how it will lead to more fires and earlier fire seasons."

Can't point to evidence but are sure it is occurring. Nice. Here is some evidence:
"New paper finds wildfires in the western US are at the lowest levels in 3,000 years"
http://hockeyscht...-us.html
"LA Times: 2013 US wildfire acreage was far below average"
http://hockeyscht...far.html
Rustybolts
1.6 / 5 (7) May 19, 2014
My bet is the drought making it worst and not global warming. Can't blame the drought on global warming.
runrig
4.3 / 5 (6) May 19, 2014
There is absolutely no credible scientific justification to link wildfire severity to a 1*c increase in GLOBAL temperatures as compared to 100 years ago. It is an abject fraud to do so, and is why no one with any sense will take these alarmist clowns seriously. They're hurtng their own cause.

The minute a critique mentions the prior 17 years pause in global temp rising, these very same charlatans claim 'it's not enough trend',... but 'yea the wildfires are worse because of AGW'. Yet, dimwits wonder why there are "deniers".

The usual lack of critical thinking there.
Try realising that an ave rise in global temps - err - like - averages out extremes, and regional changes - of which by far the most the important is the warming in the Arctic. And no, I'll not go through the changes that causes in the Polar jet-stream strength and meanderings.
There has been no "pause" in global temps rising. Unless you want (of course you do) to discount deep ocean warming.
verkle
1 / 5 (7) May 19, 2014
The same people who write this article, if they were fair and consistent, would send out alarmist warnings at the end of a mild fire season saying that this might mean the earth is cooling.

Obviously they don't. So what does it make them?

Enough of their crying wolf.

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