Skip to main content

Extreme heat and droughts -- a recipe for world food woes

By Michael Roberts, Special to CNN
August 13, 2012 -- Updated 2124 GMT (0524 HKT)
The drought had a negative impact on corn in Le Roy, Illinois. Drought occurred in six Plains states between last May and August because moist Gulf of Mexico air "failed to stream northward in late spring," and summer storms were few and stingy with rainfall, said a report by the National Oceanic and Atmospheric Administration. The drought had a negative impact on corn in Le Roy, Illinois. Drought occurred in six Plains states between last May and August because moist Gulf of Mexico air "failed to stream northward in late spring," and summer storms were few and stingy with rainfall, said a report by the National Oceanic and Atmospheric Administration.
HIDE CAPTION
Extreme heat, drought ravage Midwest
Extreme heat, drought ravage Midwest
Extreme heat, drought ravage Midwest
Extreme heat, drought ravage Midwest
Extreme heat, drought ravage Midwest
Extreme heat, drought ravage Midwest
Extreme heat, drought ravage Midwest
Extreme heat, drought ravage Midwest
Extreme heat, drought ravage Midwest
Extreme heat, drought ravage Midwest
Extreme heat, drought ravage Midwest
Extreme heat, drought ravage Midwest
Extreme heat, drought ravage Midwest
Extreme heat, drought ravage Midwest
Extreme heat, drought ravage Midwest
Extreme heat, drought ravage Midwest
Extreme heat, drought ravage Midwest
Extreme heat, drought ravage Midwest
Extreme heat, drought ravage Midwest
Extreme heat, drought ravage Midwest
Extreme heat, drought ravage Midwest
Extreme heat, drought ravage Midwest
Extreme heat, drought ravage Midwest
Extreme heat, drought ravage Midwest
Extreme heat, drought ravage Midwest
Extreme heat, drought ravage Midwest
Extreme heat, drought ravage Midwest
Extreme heat, drought ravage Midwest
Extreme heat, drought ravage Midwest
Extreme heat, drought ravage Midwest
Extreme heat, drought ravage Midwest
<<
<
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
>
>>
STORY HIGHLIGHTS
  • Michael Roberts: Extreme heat and drought are signs of a changing climate
  • Roberts: Farmers and U.S. consumers will be fine; food prices will go up a bit in 2013
  • He says the crop losses will have the most effect on the world's poorest populations
  • Roberts: This summer's extreme heat may just become typical in 15 years

Editor's note: Michael Roberts is an associate professor of economics and Sea Grant Affiliate at the University of Hawaii, Manoa. He is currently on leave from the department of agricultural and resource economics at North Carolina State University.

(CNN) -- With extreme heat and the worst drought in half a century continuing to plague the farm states, there are important lessons to be learned for all of us -- farmers, consumers and the world's poorest populations alike -- about the effect of climate change.

The Agriculture Department announced this season's first major crop yield forecasts, and they weren't pretty: a nationwide average of 123.4 bushels of corn per acre, the lowest level since 1995. Soybean yield is expected to be low too, though not as bad as corn.

The United States, which is the world's largest producer and exporter of staple grains, is grappling with the biggest surprise in production shortfalls since the Dust Bowl of the 1930s. Certainly, this July surpassed July 1936 as the hottest month on record.

So, how will the devastation affect U.S. crop farmers?

Drought to push food prices higher
Ag. Secy. on drought relief distribution
Drought troubles in the United States
Obama on nation's drought

Drought, heat bring spiders out

Since mid-June, corn prices have risen about 60%, more than twice the projected decline in yield. This means that farm revenue will go up. About 90% of the corn acreage is backed by a generously subsidized federal insurance program, described by Steven Colbert as "Obamacare for the corn," so crop farmers will be just fine. Livestock farmers who use corn to feed their animals could see higher costs, but most have contracts with processors who provide their feed grains.

What about consumers? Will high commodity prices affect the prices of food you eat? Not much, actually.

Commodity prices account for just a tiny share of retail food prices. If you're a shrewd shopper, next year you may notice higher prices for meat, milk, eggs, and cheese and all types of processed foods. The USDA estimates that food prices will increase 3 to 4% in 2013. This is not going to radically change your life. People in rich countries like the U.S. are not going to eat much less or much differently as a result of modestly higher prices.

The crop losses will have the most effect on the world's poorest populations. About 2 billion people still live on $2 a day or less. Many of them live in urban areas of developing countries. Often, they must spend half or more of their income on food, the bulk coming from staple grains like corn, wheat and rice. For these people, a huge rise in grain prices is more than noticeable -- it can literally break their budget.

In 2008 and 2011, when corn prices went up to levels nearly as high as today's, the world saw a sharp rise in food riots. Many pointed to wheat prices as a catalyst for revolutions in the Middle East, including Egypt, Tunisia and Libya. It is not hard to see that food-related security problems overseas could cost us far more than the extra pennies we'll pay at the grocery store.

NASA scientist links climate change, extreme weather

The U.S. can ease price pains somewhat by suspending government rules that mandate biofuel production. In 2011, about 40% of U.S. corn crops were diverted to ethanol (a quarter, if we take into account that nutritional content is recycled back into feeds for animals in the form of distiller grains). But this seems untenable politically.

The larger and more important issue is whether this year's bad crop yield is an omen of what we should expect going forward.

Record high temperatures are occurring with far greater frequency than in decades past, and crop yields decline sharply in extreme heat. In research that Wolfram Schlenker and I have conducted using the Hadley III climate model, we project yield declines of about 20% over the next 20 years, holding all else the same. This summer's extreme heat may just become typical in 15 years.

Some have criticized these projections as too pessimistic, and they just might be. An atmosphere richer in carbon dioxide concentrations may allow plants to transpire less water during photosynthesis, and thus, improve drought tolerance. Farmers can adjust to earlier planting times, perhaps avoiding some extreme temperatures during the sensitive flowering period, and lengthening the growing season. And new drought-tolerant crop varieties have been developed.

This season was a good test of these adaptive strategies. It appears they didn't work. Carbon dioxide concentrations are much higher than they were in 1983 and 1988, when it was nearly as hot as this summer. And farmers planted much earlier than usual, many using new drought-tolerant varieties.

Record drought is good business for some

For now, we can take a little comfort that ample harvests in the Dakotas, Minnesota and parts of the South could make up for some of the decimated crops in the central Midwest this year.

But next year? And the years after? In the long term, a warming world will be a difficult challenge for our crops and all of us.

Complete coverage: drought

Follow us on Twitter @CNNOpinion.

Join us on Facebook/CNNOpinion.

The opinions expressed in this commentary are solely those of Michael Roberts.

ADVERTISEMENT
Part of complete coverage on
July 23, 2014 -- Updated 1538 GMT (2338 HKT)
The idea is difficult to stomach, but John Sutter writes that eating dog is morally equivalent to eating pig, another intelligent animal. If Americans oppose it, they should question their own eating habits as well.
July 23, 2014 -- Updated 1630 GMT (0030 HKT)
Bill van Esveld says under the laws of war, civilians who do not join in the fight are always to be protected. An International Criminal Court could rule on whether Israeli airstrikes and Hamas rocketing are war crimes.
July 23, 2014 -- Updated 1205 GMT (2005 HKT)
LZ Granderson says Ronald Reagan went horseback riding and took a vacation after the Korean Air Crash of 1983. So why does the GOP keep airbrushing history to bash Obama?
July 23, 2014 -- Updated 1338 GMT (2138 HKT)
Aaron Miller says Kerry needs the cooperation of Hamas, Israel, Egypt and others if he is to succeed in his peacemaking efforts
July 23, 2014 -- Updated 1251 GMT (2051 HKT)
Errol Louis says the tragic death of Eric Garner at the hands of the NYPD has its roots in the "broken windows" police strategy from the crime-ridden '80s.
July 23, 2014 -- Updated 1408 GMT (2208 HKT)
Gordon Brown says the kidnapped Nigerian girls have been in captivity for 100 days, but the world has not forgotten them.
July 23, 2014 -- Updated 1127 GMT (1927 HKT)
Ruben Navarrette says Texas Gov. Rick Perry is right to immediately send 1,000 National Guard troops to the U.S.-Mexico border in response to the border children crisis.
July 22, 2014 -- Updated 1356 GMT (2156 HKT)
Ukraine's president says the downing of MH17 was a terrorist act, but Richard Barrett says it would be considered terrorism only if it was intentional
July 22, 2014 -- Updated 2015 GMT (0415 HKT)
Robert McIntyre says the loophole that lets firms avoid taxes should be closed
July 22, 2014 -- Updated 1535 GMT (2335 HKT)
Jeronimo Saldana and Malik Burnett say Gov. Perry's plan to send National Guard to the border won't solve the escalating immigration problem.
July 22, 2014 -- Updated 1742 GMT (0142 HKT)
Sally Kohn: The world's fish and waters are polluted and under threat. Be very careful what fish you eat
July 22, 2014 -- Updated 1242 GMT (2042 HKT)
Les Abend says threat information that pilots respond to is only as good as the intelligence from air traffic controllers. And none of it is a match for a radar-guided missile
July 21, 2014 -- Updated 1235 GMT (2035 HKT)
Frida Ghitis: Anger over MH17 is growing against pro-Russia separatists. It's time for the Dutch government to lead, she writes
July 21, 2014 -- Updated 1227 GMT (2027 HKT)
Julian Zelizer says President Obama called inequality the "defining challenge" of our time but hasn't followed through.
July 21, 2014 -- Updated 1157 GMT (1957 HKT)
Gene Seymour says the 'Rockford Files' actor worked the persona of the principled coward, charming audiences on big and small screen for generations
July 21, 2014 -- Updated 1417 GMT (2217 HKT)
Daniel Treisman says that when the Russian leader tied his fate to the Ukraine separatists, he set the stage for his current risky predicament
July 18, 2014 -- Updated 1642 GMT (0042 HKT)
Andrew Kuchins says urgent diplomacy -- not sanctions -- is needed to de-escalate the conflict in Ukraine that helped lead to the downing of an airliner there.
July 19, 2014 -- Updated 0150 GMT (0950 HKT)
Jim Hall and Peter Goelz say there should be an immediate and thorough investigation into what happened to MH17.
July 18, 2014 -- Updated 1507 GMT (2307 HKT)
Pilot Bill Palmer says main defense commercial jets have against missiles is to avoid flying over conflict areas.
July 20, 2014 -- Updated 1755 GMT (0155 HKT)
Valerie Jarrett says that working women should not be discriminated against because they are pregnant.
July 21, 2014 -- Updated 1953 GMT (0353 HKT)
David Wheeler says the next time you get a difficult customer representative, think about recording the call.
July 18, 2014 -- Updated 1933 GMT (0333 HKT)
Newt Gingrich says the more dangerous the world becomes the more Obama hides in a fantasy world.
July 18, 2014 -- Updated 1011 GMT (1811 HKT)
Michael Desch: It's hard to see why anyone, including Russia and its local allies, would have intentionally targeted the Malaysian Airlines flight
July 17, 2014 -- Updated 1914 GMT (0314 HKT)
LZ Granderson says we must remember our visceral horror at the news of children killed in an airstrike on a Gaza beach next time our politicians talk of war
July 17, 2014 -- Updated 1206 GMT (2006 HKT)
Sally Kohn says now the House GOP wants to sue Obama for not implementing a law fast enough, a law they voted down 50 times, all reason has left the room.
July 17, 2014 -- Updated 1214 GMT (2014 HKT)
A street sign for Wall Street
Sens. Elizabeth Warren, John McCain and others want to scale back the "too big to fail" banks that put us at risk of another financial collapse.
July 17, 2014 -- Updated 2016 GMT (0416 HKT)
Newt Gingrich writes an open letter to Robert McDonald, the nominee to head the Veterans Administration.
July 18, 2014 -- Updated 1601 GMT (0001 HKT)
Paul Begala says Dick Cheney has caused an inordinate amount of damage yet continues in a relentless effort to revise the history of his failures.
July 18, 2014 -- Updated 1404 GMT (2204 HKT)
Kids who takes cell phones to bed are not sleeping, says Mel Robbins. Make them park their phones with the parents at night.
July 17, 2014 -- Updated 1729 GMT (0129 HKT)
Buzz Aldrin looked at planet Earth as he stood on talcum-like lunar dust 45 years ago. He thinks the next frontier should be Mars.
July 16, 2014 -- Updated 1804 GMT (0204 HKT)
Mark Zeller never thought my Afghan translator would save his life by killing two Taliban fighters who were about to kill him. The Taliban retaliated by placing him on the top of its kill list.
July 17, 2014 -- Updated 1518 GMT (2318 HKT)
Jeff Yang says an all-white cast of Asian characters in cartoonish costumes is racially offensive.
July 17, 2014 -- Updated 0124 GMT (0924 HKT)
Gary Ginsberg says the late John F. Kennedy Jr.'s reaction to an event in 1995 summed up his character
July 16, 2014 -- Updated 1641 GMT (0041 HKT)
Meg Urry says most falling space debris lands on the planet harmlessly and with no witnesses.
ADVERTISEMENT