If We Dust-Bowlify Mexico And Central America, Immigration Policy Will Have To Change

The drought crippling California is by some measures the worst in the state’s history, according to the National Science Foundation. CREDIT: NOAA
The drought crippling California is by some measures the worst in the state’s history, according to the National Science Foundation. CREDIT: NOAA

Immigration policy and the funding of the Homeland Security Department are front page news. But here is a rarely-asked question raised by a new NASA study that builds on considerable recent recent drought research.

If the United States, through our role as the greatest cumulative carbon polluter in history, plays a central role in rendering large parts of Mexico and Central America virtually uninhabitable, what will that mean for Homeland Security? And will we have some moral obligation to change our immigration policy?

People often associate environmental refugees primarily with sea level rise, and that is likely to be the case in places like Bangladesh and the South Pacific. But for North America, the primary cause will be the near-permanent Dust Bowls we are creating.

Recall that during the U.S. Dust-Bowl era, some 3.5 million people fled the region. As I noted in “The Next Dust Bowl,” a 2011 Nature article reviewing the literature, “Human adaptation to prolonged, extreme drought is difficult or impossible. Historically, the primary adaptation to dust-bowlification has been abandonment; the very word ‘desert’ comes from the Latin desertum for ‘an abandoned place’.”

But what scientists tell us we are doing to our climate will be much worse than the Dust Bowl of the 1930 — worse even than medieval U.S. droughts. Indeed, Climate Central quotes Lisa Graumlich, Dean of the University of Washington’s College of the Environment, saying that the Southwest drought from 1100–1300, ”makes the Dust Bowl look like a picnic”!


Remember, the Dust Bowl itself was mostly contained to the 1930s, whereas multiple studies project that future Dust Bowls will be so-called “mega-droughts” that last for many decades — “at least 30 to 35 years,” according to NASA. Further, the 1930s Dust Bowl was regionally localized. As the NASA map above makes clear, we are on track to Dust-Bowlify much of the U.S. breadbasket and Southwest, and virtually all of Mexico and Central America. Other recent research makes clear we would also turn large parts of Amazon, Europe, and Africa into near-permanent dustbowls. And this would be “irreversible” on a timescale of centuries.

These bleak projections are not new. As far back as 1990, NASA scientists warned that severe to extreme drought in the United States, then occurring every 20 years or so, could start coming every-other-year by mid-century if carbon pollution trends continued. A quarter century of dawdling later, NASA wants us to know that the situation is even worse than they initially warned.

The researchers’ findings are unusually robust, explained lead author Benjamin Cook of NASA: “The surprising thing to us was really how consistent the response was over these regions, nearly regardless of what model we used or what soil moisture metric we looked at. It all showed this really, really significant drying,”

Here’s a video explaining their findings:

Earlier this month, we reported on this study, “Unprecedented 21st century drought risk in the American Southwest and Central Plains,” which projects that post-2050, the Southwest and Great Plains will face warming-driven droughts worse than anything we’ve seen in “ancient or modern” times.

How bad was the medieval drought?

Graumlich said that the drought during that period essentially dried up rivers east of the Sierra Nevada mountains and caused water levels at Mono Lake, an expansive inland lake in California, to virtually disappear. Highly evolved societies collapsed and descended into warfare.

These are civilization destroying, monster mega-droughts. As the news release notes, one of those droughts “has been tied by some researchers to the decline of the Anasazi or Ancient Pueblo Peoples in the Colorado Plateau in the late 13th century.”


And the post-2050 droughts we are foisting on future generations will be much worse — considerably drier and hotter. The dark brown area in the top chart corresponds roughly to the normal climate becoming “severe drought,” which of course means a great many years will be much drier. And the normal temperature will be some 9°F warmer.

Certainly, no country with rational leaders would risk self-destruction like this. Indeed, it is difficult to imagine how even a very wealthy country like ours could “adapt” to such permanent Dust Bowls over vast areas of its most habited and arable land, at least the way most people think about adaptation today.

It seems likely most would adopt the traditional means humans have used to “adapt” when facing a brutal and very long-term drought — abandonment. Of course, we are a large country and we could in theory spend vast sums relocating our population. Also, we are the breadbasket for the world, which is to say we generate a lot of surplus food today — not to mention the 40 percent or so of food we waste. So we could probably avoid mass starvation in this country post-2050 with stringent enough measures (more on that in a later post).

But what are the implications for our poorer neighbors to the south? There will be virtually no part of their countries that are not in near-permanent Dust Bowl or severe drought. And of course their coastal areas (and ours) will be trying to “adapt” to sea level rise of perhaps 3 to 6 feet by 2100 (and likely faster rise after that). Again for all but the wealthiest coastal areas, the primary adaptation strategy will probably be abandonment.

Much of the population of Mexico and Central America — likely over 100 million people (Mexico alone is projected to have a population of 150 million in 2050!) — will be trying to find a place to live that isn’t anywhere near as hot and dry, that has enough fresh water and food to go around. They aren’t going to be looking south.

Now, from a purely moral perspective, if you burn down your neighbor’s house and farm, most people would say you have some obligation to house and feed them. But what happens if one exceedingly wealthy country is the primary contributor to destroying the entire climate of another, relatively poor, country, who itself contributed only a tiny bit to that climate change? The answer seems straightforward — we do everything possible to help them.


But what will happen in the real world where this process occurs gradually over the coming decades for Mexico and Central America — at the same time United States is dealing with the self-inflicted destruction of its own livable climate?

The situation will be a humanitarian and security disaster of almost unimaginable dimensions. I do not have the answer to those questions — other than the obvious: “Let’s start ASAP down the supercheap path of avoiding this disaster in the first place.”

As I wrote in Nature, we better start slashing emissions and planning now:

We need to plan how the world will deal with drought-spurred migrations and steadily growing areas of non-arable land in the heart of densely populated countries and global bread-baskets. Feeding some 9 billion people by mid-century in the face of a rapidly worsening climate may well be the greatest challenge the human race has ever faced.

We’ve been warned. For the umpteenth time.