The decision to migrate is almost always multi-causal. It depends on political and economic factors, both on the push side [...] and the pull side.
Environmental migration or displacement often have little connection to climate change. When Bolivian rural populations move to cities because of the progressive destruction, due to floods, of the cultivated plots initially created by Jesuit missionaries, climate change is not necessarily to blame: man-made deforestation is a more important factor. When tens of thousands of Central Americans head for Mexico and the United States because of the destruction of coffee plantations, it is due to the epidemic of coffee rust and the drought caused by a cyclical natural phenomenon (El Niño), in a context of state dysfunction and collective violence.