It's all a matter of degrees

Global warming is changing wine geography, climatologists and others say

March 07, 2007|By Corie Brown | Corie Brown,Los Angeles Times

Imagine a world in which the best sparkling wines come from Surrey in southern England, not Champagne, France. A world where Monterey Bay is home to California's best cabernet sauvignons and Sweden produces world-class rieslings.

It's not science fiction. A growing number of climatologists are warning that by the turn of the next century, such a radically altered wine map could be the new reality. They say man-made greenhouse gases warming the planet are expected to shift viticultural regions toward the poles, cooler coastal zones and higher elevations.

Burgundian syrahs? Quite likely. Scientists say that, in 50 years, California's Napa could be as hot as the Central Valley's Lodi appellation is now. Bordeaux, France, is on track to have a climate similar to France's southern Languedoc region. Germany, on the other hand, will be producing luscious red wines.

"I don't think you can make a vineyard decision today based on historical information," says David Graves, one of the owners of Napa Valley's Saintsbury wines. "You have to factor in climate change."

As he paces the floor at his Carneros, Calif., winery, Graves says that vintners plant and tend their vineyards with an eye to a 50-year horizon. Now the future seems unknowable, he says.

Wine is the canary in the climate-change coal mine, according to climatologists. Even slight changes in climate can wreak havoc on high-quality wine, making it particularly vulnerable to global warming.

In young, dynamic wine regions like California, where the weather is currently considered optimal, it is difficult to track global warming's effects. So many things are constantly changing. But the research suggests that such regions may be at the edge of what is ideal. Slight climate changes could be enough to push them over that edge.

Meanwhile, in European wine regions that have struggled to ripen grapes for centuries, global warming is a cause for celebration. Each year in the last decade seems to have brought another "vintage of the century."

No question, says London-based wine critic Jancis Robinson, global warming is changing wines. "Dry German wines now are seriously delicious. English wines and Canadian wines have benefited." On the other hand, she says, wines from warmer regions including Spain and Australia are suffering the rise in temperature.

"With wine, we can taste climate change," says Gregory V. Jones, a climatologist at Southern Oregon University who is a leading researcher in the burgeoning field of wine-region climate studies and the son of an Oregon vintner. "You can honestly argue that Bordeaux is better off today. They can now consistently ripen their grapes."

The year 2005 was the warmest recorded in the United States in the 150 years that good records have been maintained. And each of the last nine years has been among the 25 warmest on record in the United States. Globally, each of the last 15 years has been in the top 25 hottest years on record.

The wine world is scrambling to guard against disaster. In a stunning bow to climate change, French wine regulators recently approved the use of vineyard irrigation, reversing centuries of tradition to rescue regions too hot for dry farming.

Scientists at the University of California at Davis are breeding new strains of vines and root stocks that can better survive extremes of heat and drought. Spanish vintners are studying whether they can plant vineyards in the cooler foothills of the Pyrenees. Belgium, Denmark and even Sweden are jumping into viticulture.

In France, the projected climate changes threaten the very definition of wine, says Bernard Seguin, a climatologist with the French National Agronomy Institute. Each one degree increase in temperature in France is equivalent to moving 200 kilometers (or 124 miles) north, he says. By the end of the century, with current warming predictions, the north coast of France will be experiencing weather that today is common for the south of France.

Up to this point, global warming has been a boon for France, Seguin says. Rising temperatures have produced wines with higher sugars and alcohol levels and lower acids that are very popular.

But what happens if Bordeaux becomes too warm?

Michel Chapoutier, a celebrated Hermitage producer in the northern Rhone, says global warming may be making his wines more popular, but he believes it has come at a price.

Traditionally, the grapes in his vineyards could be harvested with the sugars and other flavors ripening simultaneously, he says, with alcohol levels averaging 12 percent.

Today, he says, the sugars arrive too quickly, before the other flavors. Chapoutier says he must leave his grapes hanging longer on the vine waiting for full ripeness, which results in alcohol levels averaging 14 percent. To a California vintner, this might seem acceptable, but to Chapoutier, it is evidence of a buildup of greenhouse gases in the air and a warming climate.

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