Middle class appetites and rising affluence are driving up the price of food in China, home to 1.3 billion people. Growers are faced with rising demand for food just as the rural labor supply dwindles. Yet the changes in food and work preferences aren't all bad, as they reflect the human and economic development taking place in China, says Scott Rozelle, food economist and Helen Farnsworth Senior Fellow at FSI.

Policy brief: Climate trend and global crop production since 1980

Global warming is likely already taking a toll on world wheat and corn production, according to a new study led by Stanford University researchers. But the United States, Canada and northern Mexico have largely escaped the trend.

"It appears as if farmers in North America got a pass on the first round of global warming," said David Lobell, an assistant professor of environmental Earth system science and center fellow at the Program on Food Security and the Environment at Stanford University. "That was surprising, given how fast we see weather has been changing in agricultural areas around the world as a whole."

Lobell and his colleagues examined temperature and precipitation records since 1980 for major crop-growing countries in the places and times of year when crops are grown. They then used crop models to estimate what worldwide crop yields would have been had temperature and precipitation had typical fluctuations around 1980 levels.

The researchers found that global wheat production was 5.5 percent lower than it would have been had the climate remained stable, and global corn production was lower by almost 4 percent. Global rice and soybean production were not significantly affected.

The United States, which is the world's largest producer of soybeans and corn, accounting for roughly 40 percent of global production, experienced a very slight cooling trend and no significant production impacts.

Outside of North America, most major producing countries were found to have experienced some decline in wheat and corn (or maize) yields related to the rise in global temperature. "Yields in most countries are still going up, but not as fast as we estimate they would be without climate trends," Lobell said.

Lobell is the lead author of the paper, Climate Trends and Global Crop Production Since 1980, published May 5 online in Science Express.

Russia, India and France suffered the greatest drops in wheat production relative to what might have been with no global warming. The largest comparative losses in corn production were seen in China and Brazil.

Total worldwide relative losses of the two crops equal the annual production of corn in Mexico and wheat in France. Together, the four crops in the study constitute approximately 75 percent of the calories that humans worldwide consume, directly or indirectly through livestock, according to research cited in the study.

"Given the relatively small temperature trends in the U.S. Corn Belt, it shouldn't be surprising if complacency or even skepticism about global warming has set in, but this study suggests that would be misguided," Lobell said.

Since 1950, the average global temperature has increased at a rate of roughly 0.13 degrees Celsius per decade. But over the next two to three decades average global temperature is expected to rise approximately 50 percent faster than that, according to the report of the Intergovernmental Panel on Climate Change. With that rate of temperature change, it is unlikely that the crop-growing regions of the United States will continue to escape the rising temperatures, Lobell said.

"The climate science is still unclear about why summers in the Corn Belt haven't been warming. But most explanations suggest that warming in the future is just as likely there as elsewhere in the world," Lobell said.

"In other words, farmers in the Corn Belt seem to have been lucky so far."

This is the first study to come up with a global estimate for the past 30 years of what has been happening, Lobell said.

To develop their estimates, the researchers used publicly available global data sets from the United Nations Food and Agriculture Organization and from the University of Delaware, University of Wisconsin, and McGill University.

The researchers also estimated the economic effects of the changes in crop yield using models of commodity markets.

"We found that since 1980, the effects of climate change on crop yields have caused an increase of approximately 20 percent in global market prices," said Wolfram Schlenker, an economist at Columbia University and a coauthor of the paper in Science.

He said if the beneficial effects of higher carbon dioxide levels on crop growth are factored into the calculation, the increase drops down to 5 percent.

"Five percent sounds small until you realize that at current prices world production of these four crops are together worth nearly $1 trillion per year," Schlenker said. "So a price increase of 5 percent implies roughly $50 billion per year more spent on food."

Rising commodity prices have so far benefited American farmers, Lobell and Schlenker said, because they haven't suffered the relative declines in crop yield that the rest of the world has been experiencing.

"It will be interesting to see what happens over the next decade in North America," Lobell said. "But to me the key message is not necessarily the specifics of each country. I think the real take-home message is that climate change is not just about the future, but that it is affecting agriculture now. Accordingly, efforts to adapt agriculture such as by developing more heat- and drought-tolerant crops will have big payoffs, even today. "

Justin Costa-Roberts, an undergraduate student at Stanford, is also a coauthor of the Science paper. David Lobell is a researcher in Stanford's Program on Food Security and the Environment, a joint program of Stanford's Woods Institute for the Environment and Freeman Spogli Institute for International Studies. Schlenker is an assistant professor at the School of International and Public Affairs and at the Department of Economics at Columbia.

The work was supported by a grant from the Rockefeller Foundation.

"Most of the people in the world are poor, so if we knew the economics of being poor, we would know much of the economics that really matters. Most of the world's poor people earn their living from agriculture, so if we knew the economics of agriculture, we would know much of the economics of being poor." - Theodore W. Schultz, accepting the Nobel Prize in Economics, December 8, 1979           

More than thirty years ago, Theodore W. Schultz won the Nobel Prize in Economics for his work on economic development and agriculture in developing countries. Last week, Cornell University Professor Christopher Barrett told Stanford students, faculty, and community members that Schultz's ideas suggest a powerful approach to breaking persistent cycles of poverty in modern rural Africa.

Barrett, a Professor of Applied Economics and Management and an expert in poverty and international development, visited the Stanford campus for a two-hour symposium entitled "Assisting the Escape from Persistent Ultra-Poverty in Rural Africa." He described the economics of poverty and agriculture in rural Africa as a series of downward spirals in environmental and human health.

The struggle to survive on insufficient resources, he explained, leads to disease and degradation that result in still deeper poverty. Escaping this cycle requires an influx of assets - a "lump of starting capital" in both private and public goods - that Barrett said the international community can provide.

"It takes money to make money," Barrett said. "Asset holdings, and their productivity through technology and markets, matter enormously."

When African farmers and pastoralists slip below a certain threshold of asset poverty, Barrett explained, they face negative feedbacks that set off a steep decline.

For example, a farmer who cultivates the same tiny plot of land year after year depletes soil nutrients to the point where even heavy fertilizer applications cannot revive the crop. Similarly, a pastoral family that begins with a small herd may become sedentary if they are unable to provide for the elderly and infirm while keeping their animals on the move. Stuck in one place, the herd exhausts local resources, and animals and humans alike suffer the health consequences of insufficient food and water.

A farmer who begins with plenty of land can sustain higher yields and invest surplus profits in education, health care, better equipment and still more land. But for the small farmer, incentives to invest in a better future are low, because the consequences of losing even a little income - an accelerated decline toward deeper poverty - are so severe.

Subsistence activity takes precedence, and when bad weather or disease strikes, the results are devastating. Limited access to credit, technology, and markets; weak government; and a harsh physical landscape make it still more difficult for rural Africans to invest in productive assets and recover from chance shocks.

These negative feedbacks and perverse incentives, Barrett said, make African poverty uniquely persistent.

While poor families in the developed world usually experience brief deprivation as a result of job loss or another isolated event, ultra-poor families in rural Africa have exhausted their land, livestock, and other productive assets. Without the means to restore natural and human capital, they may face a lifetime of poverty.

"In the US, poverty, while distressingly widespread, is a short-term phenomenon," Barrett noted. ""It is qualitatively and ethically different to talk about people who have very little hope of leaving poverty."

But Barrett said that the next generation of rural Africans has reason to be hopeful. While there is no one-size-fits-all approach, targeted investment could improve the outlook for many poor African nations. Barrett cited a generation of successful poverty relief efforts in Asia, where ultra-poverty rates in some countries have fallen from the high teens to less than five percent.

"East and Southeast Asia were at least as grim a generation ago as Africa is today," Barrett emphasized. "We know from the historical record that the world can move a lot of people out of poverty very quickly."

Citing Schultz's Nobel Prize acceptance speech, Barrett suggested that the international community focus first on reversing the cycles of decline that have pushed so many African farmers into meager subsistence agriculture.

Farm output, he said, universally impacts the rural poor. When output increases, poor farmers gain directly by selling their surplus. The extra supply also keeps local food prices low, benefiting the vast majority of rural Africans who consume more food than they produce.

Barrett described several possible "entry points" to stimulate agricultural productivity, including direct land and livestock grants, organized provision of rural education and health care, and renewed commitment to African crop research.

Private entrepreneurs, he said, are particularly well situated to invest in the technology and infrastructure needed to open rural markets, support soil and water conservation, and improve communication between buyers and sellers.

Barrett said that relief efforts should ultimately turn their attention to moving rural Africans out of agriculture. High rural population densities have compressed average farm sizes to a fraction of a hectare, he explained, making farming an unsustainable enterprise. More and more rural Africans are suffering the consequences of trying to do too much with too little.

"They find farming hard work," Barrett said, "and they'd like their kids to be able to find something else to do."

Barrett already sees a brighter future for those farmers and their children. "With governments and private investors already increasing their commitments to agriculture and rural development in Africa," he said, "I firmly believe we are in the early stages of being on the way."

This talk was the third in FSE's Global Food Policy and Food Security Symposium Series.

Full video of the symposium is now available - Why Has Africa Been Slow in Developing its Agriculture?

A poor African farmer produces a little more corn than last year. He sells the surplus in a nearby urban market, and uses the money to purchase a shirt stitched by a local seamstress. With the bumper crop of corn, more and more farmers are interested in the seamstress' wares. The extra income allows her to buy better materials and a new sewing machine. Her business grows, and she begins to sell her work in bigger markets, further from her small village.

Years later, a poor farmer responds to an announcement for a job in a local clothing factory. The monthly wage is more than he currently makes in a year.

This is the vision that Dr. Ousmane Badiane, Africa Director for the International Food Policy Research Institute, presented to an audience of Stanford students and faculty on April 7. In a two-hour symposium entitled "Why Has Africa Been Slow in Developing its Agriculture?," Badiane outlined the steps he believes African nations must take to sustain economic growth and encourage high-value industrial development. Public investment in agriculture formed the backbone of his proposal.

Badiane said that although African nations have experienced unprecedented economic growth in the last 15 years, they still lag behind the developed world in economic sophistication. When workers leave agriculture for other sectors, he explained, the transition usually signifies economic progress.

But in Africa, too many farmers have abandoned their fields to peddle trinkets on the streets as part of a low-productivity service sector. They have left behind an underdeveloped and understaffed agricultural industry.

Agriculture has just plummeted too fast and too quickly in these countries," Badiane said. "Agriculture is not claiming the share of GDP and employment that it should."

When agriculture thrives, Badiane explained, economies grow and diversify. A wealthier rural population purchases products manufactured by urban entrepreneurs. Productive local farms buffer fluctuations in global crop output and food prices, improving security for urban industrial workers and reducing wage pressure on industrial employers.

"What agriculture needs is what industry needs," Badiane said, emphasizing that investment in one need not mean neglect of the other. "There are a lot of things you can do right by all the sectors at the same time."

In fact, according to Badiane, every $100 increase in agricultural output could result in up to a $130 increase in output from industry.

Badiane described one step that African governments have already taken to set the positive agriculture-industry feedback in motion. The Comprehensive Africa Agriculture Development Program is a cooperative effort by the African Union's 53 member nations to achieve ambitious goals for economic development and investment in agriculture by 2015.

Badiane commended the Program's unprecedented commitment to agricultural growth and its high standards for accountability, policy research, and performance review. He also praised the political momentum and unity that the initiative has generated within Africa, and the respect that it has earned in the international community.

However, Badiane admitted that agricultural growth in Africa cannot always proceed in harmony with other objectives. The need to finance agricultural research and development will put pressure on budgets for broader public welfare programs that Dr. Joel Samoff, a Stanford professor of African Studies, says most African nations simply cannot afford to de-fund.

"Most countries in Africa spend around $10 per person per year on health," says Samoff. "How do you reduce that?"

But Badiane suggested that governments may be able to address both agriculture and welfare simultaneously.

They will have to see how they can use social service budgets to sustain growth in agriculture," he said. "Look at health and education not as an entitlement, but as a tool to raise labor productivity."

Addressing the audience during a question-and-answer session following Badiane's talk, Harvard Development Professor, Emeritus, Peter Timmer drew attention to the scope of Badiane's objectives.

"You're talking about getting industry moving at the same time as you're getting agriculture moving," he noted, "and this is a very ambitious undertaking."

However, Timmer also indicated that he saw the seeds of success in Badiane's ideas. "I think we've just heard a quite profound analysis of Africa's agricultural problems, and its structural history," he said. "And a possible way forward."

Agriculture in Africa has grown steadily for the past 15 years. But that economic improvement is just making up for the preceding two decades of stagnation, says Ousmane Badiane, Africa director for the International Food Policy Research Institute (IFPRI).

And future progress toward industrialization depends on continued agricultural growth, he says.

Badiane will deliver a lecture on April 7, titled Why Has Africa Been Slow in Developing its Agriculture?. He will discuss the current state of agriculture in Africa, the technological resources available and policies needed for economic growth, and how agriculture can address the country's challenge of poverty.

The talk will begin at 4 p.m. at the Bechtel Conference Center in Encina Hall. It is free and open to the public.

A citizen of Senegal working in IFPRI's Washington, D.C., office, Badiane coordinates the organization's food policy research and communications throughout Africa.

From 1998 until mid-2008, Badiane worked at the World Bank as a lead specialist for food and agricultural policy for the Africa region.

As a senior research fellow at IFPRI from 1989 until 1997, Badiane led the institute's work on market reforms and development. He taught as an adjunct professor at the John Hopkins School of Advanced International Studies from 1993 until 2003.

Stanford's Program for Food Security and the Environment (FSE) sponsors the two-year Global Food Policy and Food Security Symposium Series, which is funded by a $1 million grant from the Bill and Melinda Gates Foundation.

Jeff Raikes, chief executive officer of the Gates Foundation, and Greg Page, chief executive officer and chairman of Cargill Inc., delivered the first lecture, Improving Food Security in the 21st Century: What are the Roles for Firms and Foundations, in February.

Future seminars will cover policy development to increase wealth, agricultural productivity and resource stewardship.

• On April 27, Christopher Barrett, an economist at Cornell University, will talk about "Assisting the Escape from Persistent Ultra-Poverty in Rural Africa."
• On May 26, C. Peter Timmer, professor emeritus of development studies at Harvard University, will deliver the fourth lecture, "Managing Food Price Volatility: Approaches at the Global, National and Household Levels"

All lectures will be videotaped and posted on the symposium website, Global Food Policy and Food Security Symposium Series.