The possibility that climate change could be responsible for violent conflict (A. Solow Nature 497, 179–180; 2013) is starting to influence how governments frame and react to climate change. However, a real problem in this area is a paucity of theory to explain the associations (if any) between climate change and the outbreak of violence.

One overlooked factor is that populations caught up in conflicts or living in post-conflict societies are often more vulnerable to climate change. For example, the presence of landmines makes productive land inaccessible.

Climate policies can themselves be a source of conflict (see go.nature.com/zutmox). Measures that manage carbon sources and sinks or treat them as commodities — such as land-use changes, hydropower development or initiatives to reduce emissions from deforestation — can stimulate civil unrest if implemented without adequate checks.

Poverty, a history of fighting, and weak governance are well-established risk factors for conflict. The likelihood of violent conflict is reduced by democracy, social protection, effective justice systems and the protection of property rights. The influence of climate change on these factors warrants further investigation to guide policy-makers in promoting peace and prosperity in a changing climate.