Will Climate Change Really Spur Mass Migrations of Mexicans to the U.S.?

By Andrew Moseman | July 27, 2010 4:35 pm

MexicanFarmEvery time governments fail to take serious steps on climate change, it seems the parlor game of predicting what our warmer world will look like heats up. And the newest of those predictions, appearing this week in the Proceedings of the National Academy of Sciences, pokes at what is presently one of the country’s most sensitive spots: immigration.

Michael Oppenheimer of Princeton published a study that estimates that between 1.4 and 6.7 million people could become climate refugees emigrating from rural Mexico to the United States between now and 2080. That’s 2 to 10 percent of the present Mexican population, and it doesn’t include people who would make the move for other reasons.

Is it a major concern? Yes. How much stock should you put in those statistics? Not much.

Oppenheimer and colleagues used projections of decreased agricultural output driven by rising temperatures to get these figures.

In the worst-case scenario would occur if temperatures were to rise by one to three degrees Celsius (1.8 to 5.4 degrees Fahrenheit) by 2080, if farming methods had not been adapted to cope with global warming and if higher levels of atmospheric carbon dioxide had not spurred plant growth. This would mean crop yields in Mexico would fall by 39 to 48 percent, the study said [AFP].

Other scientists agreed that a warming Earth could spur more migration, but questioned whether it is truly possible to disentangle climate change from other forces and pin statistics just on that.

The social consequences of global warming are always the hardest things to predict. Immigration rates are never driven by physics alone, but depend on plenty of other factors, such as U.S. border policies or the changing structure of Mexico’s economy. And it’s always difficult to tie specific social trends to climate change. People in rural areas have been migrating for a long time, whether to seek out work or because the rainfall’s dried up or the soil’s eroded [The New Republic].

In addition, the Arizona Daily Star reports that the fertility rate in Mexico has trended downward for decades. Its continued drop could cut into any migration increase tied to climate change. Douglas Massey, another Princeton professor, told the Los Angeles Times that even if agricultural production worsens, Mexicans aren’t going to come in a mass exodus in the U.S. unless there are lots of jobs here to be had.

Oppenheimer himself free acknowledges the fudgy nature of predicting climate change’s effects, and that while the numbers make for a sexy headline, you shouldn’t take them too seriously. He says:

“Our intention was to show that this problem is a substantial one. Our goal was not to project specific outcomes 80 years from now but to show the magnitude of problems that policymakers ought to pay more attention to. I don’t want to say that this will be the single biggest factor driving immigration, but it could become among the largest factors” [Arizona Daily Star].

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Image: flickr / wonderlane

  • Jo Denny

    Wouldnt surprise me in the leaast. Now is as good a time as any I guess.


  • http://www.myspace.com/allisaalloju Allisa Alloju

    Yeah the climate change is very evident now, and I think it’s not only Mexicans are going for immigration..US is going to be overpopulated sooooonn…. 😉

    -Allisa Alloju

  • fatkid

    Wake up folks, it won’t take global warming to send a tide swell of immigrants across our border. Ethanol has already driven corn prices so high that many Mexicans can’t afford tortillas! Food riots have already taken place, the Mexican gov’t is considering collective farming to provide sustanence to the impoverished masses living in, and returning to Mexico.

    Money and guns flow into Mexico in return for the drugs to slake the enormous U.S. thirst, yet we spend no money on treatment, the most cost effective way curb dependancy. At the same time we spend billions to arm the Mexican army, essentially bringing support to the narco faction dejour.

    Would you move if you were hungry and scared? Hells yeah you would. Even Arizona beats Juarez..

  • Peter

    This could very likely happen

    however these people will not be the only ‘climatic refugees’ in the coming decades.

    There will be Americans in the south/central Great Plains exiting -since the region will likely become semi desert again-unable to support agriculture. South and central Florida will likely suffer from sea rise, and rising temperatures, and drought- turning what is left of the state into a savanna type climate.

    Also The states of AZ, Nevada, Inland southern/central CA. parts of Texas, New Mexico will become uninhabitable; water shortages, drought and extreme heat-causing out migration to ‘cooler’ and greener parts of the nation.

    The great in migration to the aforementioned areas of the 20th century will likely be over this decade- areas to grow in population; Upper Midwest/great lakes, New England, up state NY, Northern CA, Oregon and Washington state(west of the Cascades)

  • Dubliner

    It makes perfect sense that people in countries which are adversely effected by climate change will migrate towards countries less impacted especially to countries that are not already densely populated and poverty stricken. People have migrated for similar reasons since we evolved. Hell even animals migrate to find food. I ‘ve been trying to point that out for a long time to fellow Irish who dismiss climate change because it won’t directly impact Ireland too badly. The indirect consequences are far reaching indeed. We will have to accommodate these people because to do otherwise would be to ignore immense human suffering.

  • rick

    way to give the climate skeptics ammo

    This has to be the most vacuous, speculative, and useless study I’ve ever seen

  • Chris

    But how many Americans are going to migrate to Canada?

  • http://www.flickr.com/photos/wonderlane/ Wonderlane

    they have a freeway infrastructure that is surprisingly modern and wonderful. It appears to be structured specifically to supply food to the US. But past the northern desert it might as well be designed to haul people as well – both ways.

    as a Catholic country, clearly Mexico is planning for a population boom of massive proportions.

  • scott

    The world is currently stuffed with people, it’s full please, no more (less for a while), thank you. Diet time. Oh well, nature never allows any population to go unchecked and out of control for too long, eventually something happens that sets the numbers back, some kind of distaster, or disease.

    I like all kinds of people and cultures, but we can’t support an endless influx of millions and millions of more people, not with the current dirty and wasteful resource use and extraction methods in place to create the type of life we live and that everyone craves.

  • http://www.earthfacts.net Joe Earth

    There have been other studies which indicate that climate change will cause migrations of human populations, not just from Mexico but from other parts of the globe. It’s something that we should be prepared for.

  • JoeR

    People closer to the equator in both hemispheres are, and will be, headed north. Yet so many people are doubting the reality of climate change.

    I find in reading those sites that say that climate problems are a myth that their evidence is very sparse and inconclusive. Recently I read Book 1 of the free e-book series “In Search of Utopia” (http://andgulliverreturns.info), it blasts their lack of evidence relative to several myths. The book, actually the last half of the book, takes on the skeptics in global warming, overpopulation, lack of fresh water, lack of food, and other areas where people deny the evidence. I strongly suggest that anyone wanting to see the whole picture read the book, at least the last half. There is also up to date information at:http://www.newscientist.com/article/dn11462-climate-change-a-guide-for-the-perplexed.html

  • http://www.medicalinsurancefortravel.org/ sacha davilak

    There’s no better way to make clean energy cheap than to make dirty energy expensive. Global Oil Socialism focuses on keeping oil cheap by taxing the global economy to foot the bill for guns and roses. Nations have no power to change this unfortunate reality. All you need do however, is change yourself.

  • http://howtoloseweightwhilebreastfeeding.com/ Shirley A. Evans

    Yes, sacha, you make a good point – the key to clean energy is changing ourselves. One by one, we can collectively make a huge change in how we do things.



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