Humans, it’s no secret, are versatile and unpredictable in how they use their land. We build mega-cities in deserts, raise crops on flood plains, live along vulnerable coast lines enjoying seas dangerously rising, and burn rain forests to create new pastures.

As it turns out, however, this versatility with land may only get us so far. The world’s growing population, coupled with climate change and limited acres of fertile soil, pose fundamental challenges feeding the world. Today, farmland claims half the surface of the planet. With world population projected to reach 9.3 billion by 2050, just how to coax more food out of each field and where to obtain additional land — without clearing forests, contributing to climate change and harming the environment — will not be easy.

Consequently, media reporting on something as basic as greenhouse gas emissions from land planted with crops for biofuels, or the value of local farming, for example, seems so 2011. Now experts say the focus should be on the nexus of agriculture and climate change as it relates to land needed to feed growing populations.

And some of the media are on the right track. A report in The New York Times addresses the link between climate change and the growing risk to the world’s food supply. The story is based on information from a leaked report by the Intergovernmental Panel on Climate Change. A final version of the report is due to be released to the public in March.

The New York Times article explains, “That globally [rising temperatures] will make it harder for crops to thrive — perhaps reducing production overall by as much as 2 percent each decade for the rest of this century, compared with what it would be without climate change.”

In that Times story, reporter Justin Gillis also addresses the new “sharp tone” of climate scientists based on research countering earlier assumptions on agriculture that had been more hopeful that increases in carbon dioxide would benefit crops. “The report also finds other sweeping impacts from climate change already occurring across the planet, and warns that these are likely to intensify as human emissions of greenhouse gases continue to rise,” Gillis reported. “The scientists describe a natural world in turmoil as plants and animals colonize new areas to escape rising temperatures, and warn that many could become extinct.”

A recent CNN report links economic vulnerability from crop losses with climate change. Extreme weather is already making it difficult to feed the world’s growing population, and things are likely to get worse. Already in Pakistan, Reuters reports, rice farmers are modifying growing methods to cope with water scarcity and curb greenhouse gas emissions. And, the Christian Science Monitor recently reported on the aftermath of a fall blizzard in South Dakota that killed tens of thousands of cattle.

Tim Searchinger, a senior fellow at the World Resources Institute and a lecturer on interdisciplinary environmental issues related to agriculture at Princeton University, says he is surprised at how little attention many pay to the link between climate change and agriculture, despite our basic reliance on the latter.

“People think that plants are free. That’s why they were a source of interest in bioenergy,” says Searchinger, adding that agriculture both affects and is affected by climate change.

Searchinger explains that agriculture has environmental costs and contributes to greenhouse gas emissions no matter what size the farm: land used for small, diverse farms and large, single crop producers each contribute to emissions. “Producing food has high environmental costs no matter what you do,” he says.

According to The World Bank, agriculture, soil erosion, and deforestation contribute to one-third of all greenhouse gas emissions. Those emissions will be difficult to keep in check given a clear need for increasing food consumption, says Searchinger. To feed the world’s 2050 projected population of 9 billion people in, global food production needs to increase by 70 percent, he says. What does that mean? Pressure on agriculture to increase yields comes at a time when climate change is reducing or threatening those very yields.

At first glance, some wonder why an increase of less than 30 percent — from 7 billion to 9 billion people — will cause production to increase 70 percent. Several dynamics are creating this challenge. And it’s not simply an equation of increasing crop yields to meet calorie needs based on what the world eats today. With a growing middle class globally and, in particular, in China, demand for more protein from meat is causing a cascade of effects. It takes 10 pounds of grain to produce one pound of meat. Not only do livestock require plentiful pasture land for grazing, but they contribute the majority of greenhouse gases through methane, a highly potent greenhouse gas.

Another factor driving the need to increase food production is the demand for making more fuel from crops. Cereals such as corn are increasingly being grown for biofuels. Furthermore, resources are diminishing in some areas, yet farmers will need to increase yields — about 3.5 to 4 more tons per acre — on the same amount of land. Currently, each acre yields about 5 tons of cereal. In the U.S., just about all the fields once taken out of production have been put back into use.

Some countries with growing populations, aware of a growing food supply gap, already are planning for increases in food demand. For instance, in September a Chinese food producer made the largest Chinese investment in the U.S. economy so far with its purchase of Smithfield Foods., Inc., valued at $7.1 billion. Similar large investments have been made in agriculture in Brazil and in parts of Africa.

The Smithfield acquisition presents significant food security issues in the U.S., says Laurie Ristino, associate professor of law, and director of the Center for Agriculture and Food Systems at Vermont Law School. Climate change is predicted to cause food production in Africa and in South Asia to decrease by as much as 15 percent in 2050, she says. She notes too that these areas are also the hotspots for population growth. Additionally, these areas are all seeing greater demand for meat protein as incomes increase in their populations, Ristino says.

“Agriculture is a dynamic system. On the current horizon, meat production is a great place to start examining every input, energy inputs and environmental inputs. How resource use plays out magnifies [the importance of] livestock,” Ristino says. The Smithfield acquisition suggests how food production in China’s livestock yields “are beginning to be maxed out,” she says.

Some solutions are within reach. A new report by the United Nations Food and Agriculture Organization suggests that farmers can cut greenhouse gas emissions from livestock 30 percent through better practices. And The Guardian has reported that “Cattle-raising contributes 65 percent of the livestock sector’s total greenhouse gas emissions, but also offers the largest potential for reductions.”

Other Resources on Climate and Agriculture Issues

Food and Agriculture Organization of the United Nations
World Resources Institute
United States Department of Agriculture Climate Change Program
One Billion Hungry by Gordon Conway
Feeding the World by Vaclav Smil

Lisa Palmer is a freelance journalist and a fellow at the National Socio-Environmental Synthesis Center, SESYNC, in Annapolis, Md. Her writing covers the environment, energy, food security, agriculture,...