Heat and Serve

In the United States, the clearest signs of climate change so far have been stern words from Al Gore and a few hotter-than-normal summers.

In Greenland, by contrast, global warming has sparked a revolution -- at least, when it comes to agriculture. A recent article in the German magazine Der Spiegel explores the dramatic new opportunities arising for the island's farmers. The article opens with a man tending his potato patch amid the roar of "an iceberg breaking apart, with pieces of it tumbling into the foaming sea." It's some of the first serious crop farming to take place in Greenland since temperatures there plunged in the "Little Ice Age" of the 14th century.

If current warming trends continue, farmers the world over will face conditions that change rapidly and unpredictably. Some niches will open, as in Greenland; others will close or mutate. As we consider the possibilities, it's worth asking whether modern U.S. agriculture techniques, which have conquered much of the globe over the past 40 years, are up to the challenge.

One glaring weak point in our food-production system is its reliance on fossil-fuel energy -- and lots of it.

Conventional farmers look mainly to synthetic fertilizers derived in part from natural gas. Between 1950 -- roughly when U.S.-style agriculture began to spread to the global south under the aegis of the Green Revolution -- and 1998, "worldwide use of fertilizers increased more than tenfold overall and more than fourfold per person," according to a report from the Center for a Livable Future at Johns Hopkins.

Moreover, U.S. agricultural production tends to be highly concentrated in a few areas -- grain in the Midwest, fruits and vegetables in California, the Southwest, and Florida. In the recent E. coli scare surrounding pre-washed, bagged spinach, it came out that three-quarters of the nation's spinach crop hails from California -- and three-quarters of that from the Salinas Valley. That means the food system leans heavily on long-haul travel.

While current information on U.S. "food miles" -- the distance food travels from farm to table -- is scarce, one oft-cited study estimates the average at 1,500 miles. Since that figure hinges on statistics from 1980, the number has more than likely increased. The ever-growing popularity of frozen "convenience" food puts ever more distance between consumers and their sustenance. And globalization means we haul in lots of, say, asparagus from Mexico and garlic from China -- and ship out loads of corn and soy. USDA trade figures [PDF] show steadily rising imports and exports, with both expected to top $60 billion this year.

If, as the vast majority of scientists believe, human consumption of fossil fuel powers the current wave of global warming, it might be time for a serious rethinking of U.S. agricultural methods.

Don't Forget Diversity

Addiction to cheap and dirty fuel sources isn't the food system's only potential weak point. Another is the rapid and stunning loss of biodiversity that has accompanied the rise of industrial agriculture.

Agriculture has always relied on biodiversity to adapt to challenges from pests and diseases. To cite a famous example, potato farmers in Peru -- where the tuber was first domesticated and 3,000 distinct species of potato have been recorded -- have never experienced widespread crop failure, because broad genetic diversity ensured resistance to pests. In mid-19th century Ireland, though, where the genetic basis for potatoes was severely narrower, disaster famously struck.

In the U.S. and Europe, plant breeders have for a century sought to rationalize the unruly biodiversity that has characterized agriculture since its inception 10,000 years ago. Their goal has been to replace traditional species, which show broad variability within a single harvest, with "pure" hybridized varieties that produce highly uniform results.

Their success has been stunning.

In the classic Shattering: Food, Politics, and the Loss of Genetic Diversity, Cary Fowler and Pat Mooney lay out the ravages committed by modern plant breeding on agriculture's genetic heritage. They cite a study showing that 97 percent of fruit and vegetable seed varieties that were commercially available in 1903 had vanished by 1983. While they stress that the figure can be used only as a proxy, since it doesn't account for varieties informally kept vibrant by small-scale farmers and gardeners, the figure is stark nonetheless.

Today, the world's key genetic storehouses are the places where our staples originally came under cultivation: places like Mexico (corn) and the Near East (wheat). These "centers of diversity," clustered in the global south, have been subjected to severe genetic erosion as hybrid varieties from the U.S. and Europe have proliferated. Unlike the robust crops of old -- which used variation to survive pests, disease, drought, and other scourges -- hybridized cultivars depend on copious doses of fertilizers, pesticides, herbicides, and irrigation.

Can such a convoluted system withstand the coming crises? As Jared Diamond showed in Collapse, history offers many examples of societies that faced rapid climate change and environmental damage. For some, food-production methods proved durable; in other cases, food production faltered and societies collapsed.

For a glimpse of things to come, consider last week's New York Times chronicle of India's water woes: "The country is running through its groundwater so fast that scarcity could threaten whole regions ..., drive people off the land, and ultimately stunt the country's ability to farm and feed its people." (The Times didn't address the effect of massive Green Revolution irrigation projects on India's increasingly fragile water table, but Vandana Shiva, the country's great champion of small-scale farming and local autonomy, has.)

India, already parched, seems distinctly unready for the challenges of global warming. And given its own excesses, the United States, global center of industrial agriculture, seems vulnerable too. While environmentalists have focused the bulk of their efforts to combat global warming on seeking alternatives to a petroleum-hungry transportation system, our equally reckless food system deserves more attention. In the end, its salvation may lie in the hands of a group long scorned by economists and development professionals: small-scale farmers using traditional seed-saving and fertility techniques.