There are few studies directly attributing changes in conflict risk to climate change in the modern era , preventing a confident assessment of the effect of long-term changes in the climate- related systems on armed conflict . However, a sizeable literature links the prevalence of armed conflict within countries to within- and between- year variations in rainfall, temperature or drought exposure, often via reduced-form econometric analysis or statistical models that control for important non-climatic factors, such as agricultural dependence, level of economic development, state capacity and ethnopolitical marginalisation . Overall, there is more consistent evidence that climate variability has influenced low-intensity organised violence than major civil wars . Likewise, there is more consistent evidence that climate variability has affected dynamics of conflict, such as continuation, severity and frequency of violent conflict events, than the likelihood of initial conflict outbreak . Moreover, research suggests with medium confidence  that weather effects on armed conflict have been most prominent in contexts marked by a large population, low socioeconomic development, high political marginalisation and high agricultural dependence .
IPCC
Climate Change 2022: Impacts, Adaptation and Vulnerability
IPCC Report