May 28, 2008

Food price inflation is just the beginning

Grim U.S. report predicts effects of warming on natural resources

By Mike Lee
UNION-TRIBUNE STAFF WRITER

Soaring food prices are very likely to become even more unstable because of global warming's effect on farming, federal officials said yesterday.

Their prediction punctuated a report published by the U.S. Department of Agriculture, the National Center for Atmospheric Research, other agencies and scientists at several universities. The researchers synthesized more than 1,000 studies in what was billed as the most extensive assessment to date of how climate change will affect the country's natural resources.

The findings come at a time of turmoil for worldwide food supplies caused by natural disasters; the use of corn for producing ethanol; the skyrocketing cost of oil, which has created a surge in prices for basic grocery items; and growing global competition for wheat, milk and other staples.

The report's authors said climate change offers a few potential positives. Those include longer growing seasons, which can help boost the productivity of pastureland and some crops.

But overall, the forecast was grim. The researchers projected an increase in crop failures, the spread of weeds, diminished effectiveness of the herbicide glyphosate, more insect damage to crops and a rise in livestock deaths.

They also cited more signs of drought severity in the West.

Some of those dynamics hit home in January for San Diego County's farmers, who had to cut their water use 30 percent starting that month. Extended water shortages could drive up costs, push more farmers out of the business and send food prices ever higher.

Archer and others highlighted the limits of yesterday's study, including the lack of comprehensive monitoring systems to detect the effects of climate change. For that reason and others, some skeptics question whether humans play a significant role in any large-scale global warming.

The new report from the Bush administration was peer-reviewed. It did not make policy recommendations, although scientists and politicians nationwide are looking for strategies to cut levels of carbon dioxide and other greenhouse gases.

“We have based our entire economy on the concept of a stationary climate . . . so clearly, adaptation is going to be difficult. We don't really know how to do it,” said Jay Gulledge, a senior scientist at the Pew Center on Global Climate Change in Arlington, Va. He did not contribute to the latest report.

The search for answers has prompted geneticists to try to make plants more drought-tolerant. Their efforts remain at the transistor-radio stage of developing electronic technology, said Julian Schroeder, a biologist at the University of California San Diego.

“When the weather affects the farmers' crops, it trickles down to the hay broker and then that all plays into the price that we end up having to pay,” said Cheryl Lange, who runs a livestock ranch in Fallbrook. “It's just like a vicious circle, and we end up at the bottom end of it.”

Besides focusing on farming, the report addressed the likely future of the nation's natural resources. Among other things, it predicted that forest and range fires will become more common, soil erosion will increase and signature plants in the Southwest – including Joshua trees – could disappear.

Unlike many climate reports that make projections for 2100, this research team limited its time frame to the next 25 to 50 years.

Scientists' climate models show much more certainty in the shorter time period than they do for a century or more. They said the world is locked into some amount of warming in the near term because of past greenhouse-gas emissions, but that the long-term future could be different if those emissions are lowered.

“Slight changes in things like temperature and precipitation can potentially have dramatic effects,” said Steven Archer, a lead author of the new report and a professor of natural resources at the University of Arizona.

“There are advances that allow you to incrementally improve drought resistance and the ability of plants to retain water,” Schroeder said. “It's hard to be optimistic right now, but one has to work on solutions.”

Like the national forecast, California's is mixed. The state's 76,000 farmers lead the country in production of fruits and vegetables, few of which were addressed in detail by the report.

In some cases, California farmers may be able to grow more heat-tolerant plant varieties and siphon business from other parts of the world, said Daniel Sumner, an agricultural economist at UC Davis who was not directly involved in the new study.

In other ways, California is vulnerable. A 2006 report said too much heat could shrink fruit sizes – a major marketing factor – and alter where some trees can grow. That analysis also said dairy production begins to decline at 77 degrees and drops significantly at 90 degrees or more.

Yesterday's report focused on major crops such as corn and soy, which generally are less vulnerable to temperature changes than other produce. Plants have different optimal ranges for temperatures, frost-free days, carbon dioxide in the atmosphere, water and other factors.

For corn, the USDA researchers predict that heat will drive down productivity in coming years – an unwelcome forecast for the price of everything from tortillas to gasoline. Rice and beans could follow suit, while plants such as peanuts and cotton could benefit from having more carbon dioxide in the air.

Whatever happens to specific crops, the overarching issue will be water – a commodity that's in increasingly short supply in the West. The USDA report said a trend toward earlier snowmelt challenges irrigation systems that rely on the mountains releasing water slowly over several months.

“If politically it continues to be impossible to build more water storage in (California), then that bodes ill for having enough irrigation water,” Sumner said.

In North County's Valley Center, grower Bob Polito has cut down many of his trees to reduce his water demand. Polito figures that water-intensive crops such as avocados and citrus will have a hard time hanging on in San Diego County without a more reliable water supply.

“I hear a lot of chain saws going around these days,” he said. “I think the people are starting to panic now. It's starting to get hot and reality is starting to set in.”

At the county Farm Bureau, director Eric Larson has an additional concern: The prospect that global warming would generate more insects, which in turn would harm more crops. Proposed state budget cuts threaten to reduce California's ability to fight invasive bugs that thrive in warmer climates.

“It's a big deal,” Larson said. “If we allow a pest like the Diaprepes root weevil to become a permanent resident, not only will farms be at risk, but native and residential landscaping will be destroyed.”

Mike Lee: (619) 542-4570; mike.lee@uniontrib.com