2 August 2013
Changes to the climate are strongly linked to increases in violence around the world, according to a report in the journal Science. It said even small changes in temperature or rainfall were associated with a rise in conflict.
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Researchers from two American universities looked at data recorded from all around the world - and found the same pattern emerge. Their examples include an increase in domestic violence in India during recent droughts, and a spike in assaults, rapes and murders during heatwaves in the US.
The report also suggests rising temperatures correlated with large conflicts - including ethnic clashes in Europe and civil wars in Africa.
The researchers say the link is substantial - and they're now trying to understand why. They believe changing conditions put pressure on resources, such as water and crops - driving some to take up arms.
Other studies show that heat causes a biological response, making people prone to aggression.
The scientists warn that a two-degree-centigrade rise in global temperatures could see personal violence increase by 15%, and group conflicts rise by more than 50% in some regions.
But other research suggests there are more complex factors at play behind most conflicts.
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information, numbers or facts collected by researchers
- domestic violence
violence that happens at home, between family members
periods of very dry weather with little or no rain
- a spike in
a sudden rise in
periods when weather is much hotter than normal
- correlated with
were directly connected with
- to take up arms
to begin fighting with weapons
- prone to
likely to behave or respond in a particular way
- at play
involved, having an effect