Climate change could cause mass Mexican immigration

Posted by Emma Woollacott

Rednecks may have to choose between their love of SUVs and their hatred of Mexicans, if predictions from Princeton University linking climate change and immigration turn out to be true.

Researchers from Princeton's Woodrow Wilson School of Public and International Affairs examined how variations in climate and agricultural yields are related to people's migration responses.

"Changes in crop yields that result from climate change occur over broad geographical areas and are likely to lead to long-term population shifts," said research associate Shuaizhang Feng.

"Such a phenomenon is especially relevant to developing countries, which typically have large rural populations that derive a living directly from agriculture."

The study focused on Mexico from 1995 to 2005, when there was a big rise in emigration to the US. Many Mexican farmers said they were fleeing because they could no longer maintain their previous way of life because of climate-driven crop failure.

To examine this phenomenon, the team used a statistical estimator - a tool that uses only the portion of variations in crop yields across states that's predicted by changes in climate -  to estimate the sensitivity of emigration to crop yields.

Projections were used to estimate future migration flows, assuming all other factors except climate would be unchanged.

The researchers calculated that an additional one to seven million Mexicans - up to 10 percent of the adult Mexican population - could migrate to the US in the next 70 years.

"The purpose of the study is to determine if the magnitude of immigration flows due to climate change could be significant, to underscore areas where further research is needed, and to provide insights for policymakers who may need to plan to manage the multitude of problematic outcomes of climate change, such as this one," said Professor Michael Oppenheimer.

Professor Alan B Krueger said, "The methods that we developed in the study could be applied more generally to understand and project worldwide migration trends over the next 70 years, and to help governments and nongovernment organizations prepare for population inflows and outflows."