Fascinating NPR story on an MIT study of the impact of climate on the economic output of poor countries.
Listen here or read the transcript below:
Hot Climates May Create Sluggish Economies
by David Kestenbaum
Morning Edition, July 17, 2009 ·
New research suggests that higher temperatures can have a damaging
effect on the economies of poor countries. The study, by economists at
the Massachusetts Institute of Technology, found that in years with
higher temperatures, poor countries experienced significantly slower
economic growth.
The research adds to an economic puzzle that
dates back hundreds of years: Why do the poorer economies of the world
tend to be in hot places, while the more successful economies are found
in cooler climates?
The French writer Montesquieu wondered about
it in the 1700s. Now there is significantly more data to work with. A
graph of per-capita GDP and average temperature shows rich countries at
one end — Norway, Germany, France and the U.S. — and poverty at the
other end in Cambodia, Liberia and Congo.
Many researchers have written this off as a historical accident, perhaps a legacy of colonialism.
Ben
Olken, an associate professor of economics at MIT, and his colleagues
wanted to examine the temperature connection more closely. They decided
that instead of comparing one country to another, they would look
within countries. Did a hot year mean slower economic growth?
The
answer appears to be yes. They found that for poor countries, an
increase in annual average temperature by 1 degree centigrade
corresponded to a 1.1 percent drop in per-capita gross domestic product.
It's
"a huge effect," Olken says. The difference between a country that's in
recession and one that is buzzing along amounts to a 3 percent shift in
GDP. "So, 1 degree explaining a 1.1 percent shift is a huge effect of
temperature."
It's unclear exactly why temperature would have
this effect. It might be that crop yields go down, or that disease is
more of a problem. Or it might just be what you could call the "sloth"
theory — it's hard to work when it's hot out. Who wants to mow the lawn
in August?
"This stuff is not implausible," Olken says, "If you
look back at the U.S. before the advent of air conditioning, there were
times when the federal government would shut down. It was too hot out."
The
researchers found that temperature shifts did not appear to affect the
wealthier countries, perhaps because of air conditioning, or because
they already are situated in cooler climates.
The results suggest that global warming could increase the gap between rich and poor.
"One
of the takeaways I have from this paper is it seems like the economic
impacts of increased temperature in poor countries are going to be very
severe," Olken says.
William Easterly, an economist at New York University, says the new study is fascinating, but he's not convinced.
"It's
way too soon to take one statistical finding and say we have solved a
500-year-old problem of why temperature and per-capita income are
associated with each other," Easterly says.
Easterly says he
thinks cooler countries have stronger economies because of a historical
accident. "It was Europeans who discovered first how to set up a
prosperous market economy," he says. Europeans spread to other
temperate parts of the world. That explains why the rich economies are
there today.
Why didn't the hotter parts of the world catch up?
"When you're ahead, you tend to stay ahead," Easterly says. The slave
trade was one example of how that played out. "Europe and America
benefited from the profits of the slave trade. And Africa was
permanently harmed by the slave trade."
Olken says his team has
checked and rechecked its results with a number of data sets. He says
the temperature and GDP correlations keep showing up.
Whatever
the cause, there are some countries that buck the trend. Singapore is
just about on the equator and has a strong economy. Indonesia is
growing fast.
Easterly says the great hope of global trade is
that countries can adapt to do whatever makes sense in their part of
the world. With time, they can overcome climate, even history.
Photo courtesy of NPR.org.