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."
The researchers looked at 60 studies from around the world, with data spanning hundreds of years.
They 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.
Mr Burke said: "We want to be careful, you don't want to attribute any single event to climate in particular, but there are some really interesting results."
The researchers say they are now trying to understand why this causal relationship exists.
"The literature offers a couple of different hints," explained Mr Burke.
"One of the main mechanisms that seems to be at play is changes in economic conditions. We know that climate affects economic conditions around the world, particularly agrarian parts of the world.
Looks like the confusion between correlation iand causation is one of bad reporting. From the Science article itself (page 2):
Reliably measuring an effect of climatic conditions on human conflict is complicated by the inherent complexity of social systems. In particular, a central concern is whether statistical relationships can be interpreted causally or if they are confounded by omitted variables. To address this concern, we restrict our attention to studies with research designs that are a scientific experiment or that approximate one...