Let’s say you are convinced that climate change is a huge threat and will have catastrophic consequences for humankind in the foreseeable future. How exactly do you envision that catastrophe playing out?
Most people I speak with, and most accounts I’ve read and seen, lean toward the apocalyptic. But what are the mechanisms by which disaster strikes? Where does it occur? Who is most likely to suffer?
According to a fascinating new working paper (abstract here; download available here) by Melissa Dell, Benjamin F. Jones, and Benjamin A. Olken, the answer to that last question may be an easy one: poor countries.
This answer may not surprise you very much, but Dell, Jones, and Olken have done a good job of showing the relationship between climate and the economy, and their paper may substantially inform the way that people — especially in the U.S. and other rich countries — consider the possible effects of climate change.
Here is the excellent first sentence of their paper:
Climate change may — or may not — be a central issue for the world economy.
Just in case it is, here is what they decided to do: take the historical temperature and precipitation data for every country in the world from 1950 to 2003 and combine it with the data for economic growth to see the overall effect that earlier climate change has had on economies.
The world has gotten a bit warmer and a bit drier over the past 50 years. The presumption is that it will get even warmer and drier over the next 50 years, so if economic changes from the past can be understood, perhaps future economic changes can be estimated. Here is the gist of their findings:
Our main results show large, negative effects of higher temperatures on growth, but only in poor countries. … In rich countries, changes in temperature have no discernible effect on growth.
What does this mean? Among other things, it may mean that many Americans — who are by definition rich — are worried about the wrong thing. Instead of thinking about weather apocalypses, they should instead be thinking about border invasions: the huddled masses from the poorest countries who will be seeking refuge as their own economies collapse. This would be Darwinism on the most epic scale imaginable — but instead of the finch with the shorter beak becoming extinct, it’ll be the poorest millions, or perhaps billions.
That, of course, is assuming the Earth keeps getting warmer and that warmer temperatures in fact disproportionately punish poor countries as Dell, Jones, and Olken suggest. (In an e-mail reply, they also raise an important caveat: “There are potentially other factors, such as sea level rise, which are outside the scope of our historical analysis.”) But in light of their compelling overview, it’s worth revisiting some other scholars’ work on the effects of climate change. For instance:
- Twenty-nine of 43 countries in sub-Saharan Africa experienced some kind of civil war during the 1980’s or 1990’s. The economists Edward Miguel, Shanker Satyanath, and Ernest Sergenti discovered that one of the most reliable predictors of civil war is lack of rain. If you have a largely agricultural economy, when the rain goes so does the agriculture, which makes political and economic breakdown much more likely.
In a rich country like the U.S., meanwhile, consider these findings from a pair of papers by Olivier Deschênes and Michael Greenstone:
- In the first paper, they use long-run climatological models — year-by-year temperature and precipitation predictions from 2070 to 2099 — to examine the future of agriculture in the U.S., and find that the expected rises would actually increase annual agricultural production — and therefore profits — by about 4 percent. Some states would be winners and other states losers but overall, climate change would be good for U.S. agriculture.
- In the second paper, Deschênes and Greenstone look at what a temperature increase means for mortality in the U.S., and find that the predicted climate change “will lead to an increase in the overall U.S. annual mortality rate ranging from 0.5 percent to 1.7 percent by the end of the 21st century.”
Sounds bad, yes? Think again: “These overall estimates are statistically indistinguishable from zero, although there is evidence of statistically significant increases in mortality rates for some subpopulations, particularly infants.”
In other words: the likeliest victims are, once again, the poorest people. Which means that if the relatively rich people who are currently most vocal about climate change are also the people who stand in the least danger, there may come a point where they realize that their concern is not so much an act of self-preservation as an act of altruism. Considering how impure much of our altruism is, that could be the most dangerous news of all.
[Note: Here's a discussion about this subject from the public-radio show The Takeaway.]
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Eh, based on bills presented in Congress, I think illegal immigration is as big of an issue (if not bigger) as climate change.
Though this does look like a compelling argument for foreign economic aid packages. Also, isn’t the Mexican economy growing? I read somewhere, I think on this blog, that immigration was slowing down because of the weak economy and tighter security.
More proof that any research can get monetary backing if you only include some mention of climate change. Interesting that they chose the post-WWII timeframe, since that meshes nicely with post-colonialism in Africa, too. The Europeans’ plan didn’t turn out to be much more than ‘Draw a bunch of artificial boundaries all over the map then get out.’ Then a half century of varying degrees of war starts. Who knew? But yea, global warming.
Is this really a new idea? I’ve been under the impression that the poorest countries are the ones who will suffer the consequences of global warming for some time now. One of the arguments I’ve heard is that it isn’t fair for the countries that cause global warming to suffer the least from it. This is not new.
All the more reason not to fight climate change by essentially constricting the world economy. Let the poor countries use their natural resources and cheap energy sources to build wealth. Rich countries can adapt to climate change much better than poor ones can. Our goal should be making everyone wealthier rather than shrinking our economies in a futile attempt to control earth’s climate. I would rather live in a rich warm world than a poor 2 degrees cooler world. It is crazy to eliminate our cheap energy sources when we don’t have to.
I think I’ve also read something about how much of the worlds poor population lives very near the ocean or river banks, meaning a rising tide would be especially damaging to the poor.
I just don’t understand how the world has gotten drier (and will continue to). We learned about the water cycle back in 2nd grade. And if the ice caps are melting due to Global Warming… well doesn’t that just mean there’s MORE water? And if it’s getting warmer out… that means more evaporation… which means more precipitation. I’d love an explanation here.
#6 – There are some good books out there about the shrinking water supply, one is ‘Outgrowing the Earth: The Food Security Challenge in an Age of Falling Water Tables and Rising Temperatures’ by Lester R. Brown.
Basically, because of shrinking water tables land undergoes desertification (where the salt stays on the surface, making the soil worthless for crops). These deserts will continue to evaporate water, but get very little precipitation (as I understand it, in order to get rainfall there has to be a certain level of humidity in the air – which there isn’t in a desert).
The more we reroute rivers and drill water wells, the more land will become useless. In China, the Gobi and Mongolian deserts will eventually merge and create a super desert.
Additionally, because societies are getting wealthier, we’re eating more meat. Livestock consume much more water than humans (or crops).
There are also a multitude of other reasons why water supplies are dwindling.
It is always very interesting to notice how they only look at the last 50 years or so. We will find if they open their eyes the climates have gone up and down during the last several hundred years. Global warming and global cooling in cycles. I wish these so called scientists would look at the whole picture and bring us some fuller truth and facts than presumptions only looking at a quarter of the data.
That is what science is all about right? Create a hypothosis, look at all of the evidence, cross check evidence, then make a guesstimate at what is coming next!!
If everyone only looks at the environmentalists agenda and only at a quater of the data we are going to go insane when one little hiccup happens. Then when everone freaks out on this little hiccup we will become slaves to the tyranny of a few!!
Duane