Climate change and conflict have gone hand-in-hand for the past 500 years, a study reveals.
It is the first time that a clear link between war and changing global temperatures has been identified in historical data, according to the researchers involved. The results are also significant because some experts predict that current and future climate change may result in widespread global unrest and conflict.
Most recently, the secretary general of the United Nations, Ban Ki- Moon, wrote in an article published in The Washington Post that the on-going conflict in Darfur, Sudan was "a conflict that grew at least in part from desertification, ecological degradation, and a scarcity of resources".
Other experts are concerned that rising sea levels will create a new type of refugee - referred to as the "climate refugee" - by displacing millions of people who currently live in low-lying coastal regions.
A recent study linked climate change to 1000 years of conflict in China, but until now, few studies have looked at whether long-term climate change in the past has been accompanied by increased conflict on a global scale.
"Our basic model is that deviations in temperature can hamper crop production," says Peter Brecke of the Georgia Institute of Technology in Atlanta, US. This, in turn, has three effects: increasing food prices, a greater risk of death from starvation, and increased social tension, which leads to violent conflict.
Brecke and colleagues in Hong Kong, China, and the UK scanned worldwide historical records on food prices, population levels and conflicts and compared this data with long-term temperature records. The data extended as far back as 1400.
"We found that anecdotes [of climate changes leading to conflict] seem to fit a broader pattern," says Brecke.
Most notably, Brecke and his team noticed a relatively peaceful period between the early 1700s and the early 1800s, compared to the previous 250 years. They first noticed the pattern in Europe, then found that it held true in China as well.
The 100 year period came just before the end of Little Ice Age, which lasted from 1450 to the late 1800s. When the researchers looked at temperature records, they found that it corresponded to a short term 100-year warming period.
Brecke acknowledges that temperature is not the only factor that causes wars, but believes it can exacerbate the conditions. The researchers believe that cooler temperatures during the Little Ice Age caused a drop in crop yields which exacerbated conflicts.
The 100-year warming period would have briefly relieved social tensions, he says. But, from the early to mid-1800s, temperatures dropped again, and conflicts resumed.
Although the world is now predicted to get warmer, not cooler, the researchers point out that forecasts suggest global warming will lead to long-term food shortages much as cooling did during the Little Ice Age, by disrupting global water cycles.
"Modern societies have more mechanisms to cope with these problems," says Brecke. But he cautions that the mechanisms may fail if society is forced to cope with a whole slew of environmental problems at the same time, as is predicted by several major environmental reports.
"If other problems emerge that impede our ability to address [food shortages] we may well see warfare erupt, and it should not be that big a surprise," he told New Scientist.
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Cause And Effect Seem Backwards
Tue Nov 20 01:17:39 GMT 2007 by Mark Bender
I think article has it cause and affect backwads. I mean the title seems to imply that war causes global warming but its quickly changes to speculation about potential wars caused by global warming.
I can appreicate the need for catchy titles but the logic of this article seems confused. Or at least it left me confused.
Catchy Title-wrong Logic
Tue Nov 20 03:49:22 GMT 2007 by David Stewart
I agree with Mark. Title Is Misleading to the story that is told.
The Title Reads Correctly.
Tue Nov 20 07:17:46 GMT 2007 by Maria
It says "war has links to"... The words "links to" clearly imply that war is the dependant variable here and is affected by various factors (in this case climate), which is precisely what the article is saying.
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