Image: TheGiantVermin via flickr
There's a lot of talk in these pages about the link between climate change and extreme weather events, and about the impacts of climate change on developing countries, including the risk of greater food insecurity. But yields are declining in the U.S. as well, even in communities where climate change denial might be a constant focus of conversation.One of the most important points to keep in mind is that the risks to agriculture are largely a result of increased variability in climate—the lack of predictable weather patterns that generations of farmers have relied on for successful harvests.
This quote from Professor of Agricultural Meteorology and Director of the Climate Science Program at Iowa State University Eugene Takle sums up the situation pretty well: "Farmers [in the Midwest] say they don't believe in climate change, but you look at how they spend money and are adapting," he said, pointing to newer machinery capable of faster and denser seeding, and changes in humidity, for example, which has led to higher night-time temperatures, which corn does not like.
"It's very important that we recognize the vulnerability," he said. "Huge reservoirs have just vanished. You can't do a work around."
Takle is featured in a recent Reuters story about the impact of climate change on the "world's breadbasket,' which explains:
When horrific images of drought or famine in Africa, Asia or other regions land in American media, America is usually first in line with food aid shipments, air drops, and other rescue efforts from its seemingly endless stores.
The U.S. alone accounts for half of all world corn exports, 40 percent of soybean exports and 30 percent of wheat exports.
But climate change fears are sounding some warning bells.
Some scientists and agronomists are becoming increasingly concerned about the real effects they see now on growing conditions in the Midwest, the vast black-soiled region long the core region of the U.S. agricultural miracle.
They also say that not only skeptical farmers but also government authorities are trying to quietly adapt, from equipment to planting to research.
"We don't have a long-term reserve. We have a global food supply of about 2 or 3 weeks," said Eugene Takle.
Research Picking Up
According to the U.S. Global Change Research Program, agriculture comprises 70 percent of the U.S. Midwest, which bears risks:
As temperatures continue to rise, the optimal zones for growing certain crops will shift. Pests will spread northward and milder winters and earlier springs will encourage greater numbers and earlier emergence of insects. Projected increases in precipitation are unlikely to be sufficient to offset decreasing soil moisture and water availability due to rising temperatures and aquifer depletion.
Katharine Hayhoe, an Atmospheric Science professor at Texas Tech University, said U.S. corn yields are expected to drop 20 percent with a 2-degree increase in global temperatures, or 40 percent with a 3-degree increase.
It's not just climate scientists that are worried. The USDA has its own Climate Change Program Office, which recognizes the link between climate change and agriculture, and is working on adaptation strategies. The June announcements alone from the Climate Change Program Office included new funding for projects to reduce greenhouse gas emissions in 24 states, grants to help agriculture producers adapt to climate change, and a study of "Climate Change Impacts on Crop Insurance."
Decreased yields don't bode well for a promising future for the country, especially if what we've seen from compromised global yields is any indication. A recent study in the journal Science found that world wheat production fell between 1980 and 2008, and was 5.5 lower than it would have been without any change in temperatures and rainfall, and corn output fell 3.8 percent. "According to the authors, the drop-off in production may be responsible for the 6 percent rise in food prices since 1980," the journal wrote.
"That's a $60 billion a year jump in what consumers paid for food"—so far, and the trends in climate change certainly aren't going away.
More on climate change, agriculture, and food security:
Population Growth, Climate Change Degrade African Soil, Threaten Millions With Starvation: Worldwatch
Asian Rice Yields Drop As Climate Change Warms Nighttime Temperatures
Global Warming to Disrupt Food Supply in Asia, Africa, and Latin America, New Study Warns