IIASA-led research has established a causal link between climate, conflict, and migration for the first time, something which has been widely suggested in the media but for which scientific evidence is scarce.
There are numerous examples in recent decades in which climatic conditions have been blamed for creating political unrest, civil war, and subsequently, waves of migration. One major example is the ongoing conflict in Syria, which began in 2011. Many coastal Mediterranean countries in Europe are also inundated with refugees arriving by sea fleeing conflict in Africa.
IIASA researchers Guy Abel (also affiliated to Shanghai University), Jesus Crespo Cuaresma (also Vienna University of Economics and Business), Raya Muttarak (also University of East Anglia), and Michael Brottrager (Johannes Kepler University Linz) sought to find out whether there is a causal link between climate change and migration, and the nature of it. They found that in specific circumstances, the climate conditions do lead to increased migration, but indirectly, through causing conflict.
“This research touches upon the topic widely covered in the media. We contribute to the debate on climate-induced migration by providing new scientific evidence,” says Muttarak.
Asylum seekers are more likely to be influenced by conflict than usual migrants, so the researchers chose to use data from asylum applications from 157 countries from 2006-15 to study the patterns. These data were obtained from the United Nations High Commissions for Human Rights (UNHCR). As a measure of climate conditions in the asylum seekers’ original countries, the team used the Standardised Precipitation-Evapotranspiration Index (SPEI), which measures droughts, compared to normal conditions, through identifying the onset and end of droughts, and their intensity, based on precipitation, evaporation, transpiration, and climatic conditions such as temperature. To assess conflict, Abel and the team used data on battle-related deaths from the Uppsala Conflict Data Program (UCDP).