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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The book _Collapse_ by Jared Diamond makes it abundantly clear that the poor suffer first when a society collapses. In fact he mentions that almost all of today’s immigration to rich countries is because of some sort of collapse of a poorer society.
Mike: I’m not an expert. I just play one in blog comment sections, but I think it’s about quality, not quantity of water. Torrential rains that lead to floods in the midwest, high quantity, low quality. Hurricane: high quantity, low quality. Global warming isn’t about a lack of water.
the only thing to affect global financial climate change are the trade restrictions ..placed on the poor countrys by US THE RICH ONES..
dane
Sounds like making poor countries richer would make them better able to deal with the effects of global warming. The study used historical growth rates to project future base growth, but I don’t know how realistic that assumption is. Is it possible that the base growth rates of poor countries will be higher than their growth rates were from 1971-2003?
Also, it would be interesting to have the study include the economic effects of the various carbon restrictions being proposed to see how they affect countries’ wealth and consequent ability to deal with the effects of global warming.
Pick a world-ending catastrophe; global warming, over-population, fuel shortages, water shortages, food shortages, shortage shortages, and it is always the poor who will suffer BECAUSE THEY DON’T HAVE THE MONEY TO TAKE CARE OF THEMSELVES!
The late, great Sam Kinison had a joke along these lines. He wanted to know why, whenever starving people in Africa showed up in ads on TV, they didn’t just MOVE TO WHERE THE FOOD IS!
I’m with Captain Obviousness @ 4. We need to concentrate on increasing wealth, not just handing it out. After all, we are witnessing two Third World countries marching towards modernity in India and China. Former “peasants” (for lack of a better word) in India and China are now better able to withstand the effects of a catastrophe because they now have better means to care for themselves.
When the folks in Africa and New Orleans decide to join the march, they’ll be better off, too.
Sweet Hay-seus there are some seriously uninformed commenters on this blog.
#4 – Sure, we will all be so much better off when we have paid for New Orleans, Miami, and New York to be rebuilt after repeated flooding thanks to the 20′ rise in sea level after Greenland’s ice melts.
#5 – It isn’t just the poor that live near sea level. Plenty of the developed world does too.
Actually I agree with the other Mike (comment 6). Going on what I’ve been taught and what I’ve read, global warming will, in fact, cause an increase in global precipitation. That’s not to say that there could be local decreases in precipitation in desert areas for example, but the major problem associated with it will actually be an increase in the risk of flooding, be it due to more rain or higher sea levels.
People are wrong to question the scientific data on carbon dioxide; the fact is that levels of the gas are higher than at any point in the last half a million years or so. What can be questioned perhaps is the popular assumption that greenhouse gases are the sole governer of global temperatures. Even if you look at a relatively short timescale such as the last 10 or 20 thousand years it can be seen that temperatures have varied considerably, despite a relatively constant level of CO2. Global warming seems to happen periodically all on its own. I can’t argue with the theory of greenhouse gases heating the planet up, but isn’t it possible there is something else going on here as well?
Having said that, regardless of whether or not we are to blame for global warming there is significant evidence that it is happening. What would worry me more than anything else in relation to this is the crazy levels of population growth in the poorer countries. If basic resources, in particular food and water, are going to be hit by global warming then how on earth can this continue?
It appears that their historical approach fails to account for any feedback loops that accelerate the warming trend. Their implied lower impact on richer nations and economies may not scale properly when these feedback loops are applied.
Without a doubt, poorer nations and economies will suffer most as they have less resources to adapt to changes or to improve their conditions.