A new study has found a direct connection between changing climate and an increase in warfare and conflict. Meteorologists at Columbia University examined the relationship between the weather pattern known as El Niño and the rise in civil unrest in the world’s poorer tropical countries. Of the 234 civil wars or uprisings that took place between 1950 and 2004, researchers say El Niño influenced 48 of them. Unrest in Chad, Congo, Eritrea, Indonesia, Rwanda, Burma and Niger, for example, all occurred during a particularly strong El Niño in 1997. El Niño is a regular climatic event that tends to warm up and dry out tropical regions.