Shifts in climate are strongly linked to increases in violence around the world, a study suggests.
US scientists found that even small changes in temperature or rainfall correlated with a rise in assaults, rapes and murders, as well as group conflicts and war.
The team says with the current projected levels of climate change, the world is likely to become a more violent place.
The study is published in Science.
Marshall Burke, from the University of California, Berkeley, said: "This is a relationship we observe across time and across all major continents around the world. The relationship we find between these climate variables and conflict outcomes are often very large."