Shifts in climate are strongly linked to increases in violence around the world, a study suggests.
Scientists at two universities in the United States 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 BBC reports.
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."
The researchers looked at 60 studies from around the world, with data spanning hundreds of years and report a "substantial" correlation between climate and conflict.
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 larger conflicts, including ethnic clashes in Europe and civil wars in Africa.
Scientists estimate that a 2 degrees Celsius rise in global temperature could see personal crimes increase by about 15%, and group conflicts rise by more than 50% in some regions.