The large climate oscillations, like El Niño or the Indian Ocean dipole, could play a much more significant role in armed conflicts than previously thought. This is revealed by a study conducted by researchers from Rice University (United States), published in the journal Proceedings of the National Academy of Sciences on Monday, May 11. Over several years, this team of eight scientists compiled a dataset documenting over 500 onsets of civil conflicts and wars occurring between 1950 and 2023, to understand if certain climatic phenomena increased the risks of escalation and violence.
“We wanted to understand if the risk of armed conflict is linked to these climatic variations, and if the risk of local conflict is proportional to the influence of these variations on the local climate,” explained Tyler Bagwell, one of the authors. With this approach, him and his colleagues aimed to identify regions of the world where weather disruptions make societies more fragile and exposed to political or social tensions.
Their research focused on two climatic phenomena. The first is El Niño – Southern Oscillation (ENSO), which has impacts beyond the South Pacific, and the second is the Indian Ocean dipole (IOD), which is less publicized but highly influential around East Africa and Southeast Asia. “The extreme phases of ENSO and IOD are each associated with distinct local climate impacts, often opposite to each other,” noted Tyler Bagwell.
While some regions become drier, others receive more rainfall. “By exploiting these differential impacts, we then established statistical correlations between the location and date of armed conflicts, the El Niño or La Niña phase of ENSO, and the dry or wet impacts experienced by the societies involved,” continued the scientist.
The study notably shows that violence increases in regions affected by drought during El Niño. “The global risk of armed conflict is higher during El Niño than during La Niña,” observed the scientists. Conversely, in regions where “the unruly child of climate” brings rain, the authors found “no credible link” to an increase in conflicts.
This conclusion reinforces the idea that water scarcity, agricultural losses, and pressure on food resources can become aggravating factors in economically or politically vulnerable countries.
Unlike ENSO, where only one phase (El Niño) seems to be associated with an increased risk, both phases of the Indian Ocean dipole are linked to the emergence of conflicts, especially in the Horn of Africa and Southeast Asia. “This is a very different pattern. The Indian Ocean dipole operates on shorter time scales and can evolve rapidly, creating abrupt climate variations that can destabilize already vulnerable regions,” summarized Professor Sylvia Dee, who considers it a “multiplier of threats.”
Even though the authors point out that climate does not directly cause wars, they argue that certain climate models do indeed alter the probabilities of their occurrence. Since El Niño or the Indian Ocean dipole can be predicted several months in advance, the researchers hope that their study will help improve early warning systems and humanitarian preparedness in the affected areas around the world.
