What rising temperatures may mean for world’s wine industry(1)
Warming temperatures associated with climate change are already affecting vineyards from France to Chile, often in beneficial ways. But as the world continues to warm, some traditional winemaking regions are scrambling to adapt, while other areas see themselves as new wine frontiers.
by john mcquaid
Fifty years ago, English wine was something of a national joke. “Wine making was for the very eccentric. It was drunk as a curiosity and often spat out,” says Richard Selley, Emeritus Professor of Geology at Imperial College, London and author of the book The Winelands of Britain. Wine has been made in Britain since the Romans imported it 2000 years ago. But production declined starting in the 17th century, due in part to cooling temperatures, and all but disappeared after World War I. Modern England’s chilly, rainy climate didn’t provide the minimal number of days of warmth and sunlight that even cooler-weather grapes need to ripen properly and make a commercial product.
Then came climate change. Between 1961 and 2006, temperatures in southern England increased an average of 3 degrees Fahrenheit. English wine came roaring back.
Today, there are about 400 commercial vineyards. English sparkling wines are beating their French rivals in international competitions. “We’ve noticed the climate has improved consistently. The weather has improved, the ripening period has become longer, and year after year we’re getting quality fruit,” says Chris White, the general manager of the Denbies Wine Estate in Dorking, England’s largest vineyard at 265 acres. Denbies is anticipating an even warmer future. In 2010 it planted seven acres of Sauvignon Blanc vines, a grape originating from the warmer Bordeaux region of France.
Few products are more sensitive to changes in temperature than wine. So the rising temperatures and associated with climate change are already reshaping the industry. Production as a whole is moving north (or south in the southern hemisphere) as opportunities open up in once-inhospitable areas. Meanwhile, vineyards in warmer climates are facing mounting problems as it gets hotter. Assuming projections of much hotter world prove true in the next 50 to 100 years, many winemakers will be forced to change their signature products, move, or go under. Many will go under no matter what they do.
Scientists have been analyzing the influence of climate and weather on wine since long before global warming became an issue. Over the past two decades, dozens of studies have mapped the emerging impacts of warming temperatures on vineyards in Europe, the Americas, Australia and elsewhere, and modeled the possible effects over the next 100 years. They paint a picture of accelerating change unlike anything seen before.
“If we look at the best data we have — there’s some data that goes back 500 or so years, and some paleoclimate stuff going back much further — on balance, changes underway today are as big or bigger than anything in those records,” says Gregory V. Jones, a climatologist at the University of Southern Oregon who specializes in climate’s effects on wine.
The wine industry’s early encounter with climate change is a window on the upheavals global agriculture will face over the coming century. It shows how even modest temperature and weather changes can have effects that reverberate through crop yields, business strategies, and economies — and on into culture, traditions, and even the subtle flavors that define national identities.
So far, interestingly, rising temperatures have been mostly good for wine. A 2005 study led by Jones found that the average growing-season temperature in 27 prime wine-producing regions around the world had risen 2.3 degrees Fahrenheit in the previous 50 years. In the vineyards of Spain, Portugal, southern France, and parts of California and Washington state, it rose a dramatic 4.5 degrees. But Jones also found that, in general, wine quality ratings rose with the temperature.
Warmer temperatures in general tend to produce more consistent grape harvests. The heat also hastens ripening, producing grapes with bolder flavors, more sugar, and wine with more alcohol. (This trend has coincided with rising popularity of robust, fruitier wines.)
French wine maker Philippe Bardet who produces Merlot, Cabernet Sauvingon and Cabernet Franc grapes in the Bordeaux region, says that over the past 25 years his harvests have moved from late October to the beginning of September as grapes ripen ever faster. Concerned that this may be affecting the wine, Bardet has tried planting different, slower-ripening grape varieties to push it back. In fact, Jones, in his study, found that some warmer regions were already reaching a heat threshold beyond which quality began to decline.
In Spain, changes are now coming rapidly, says Miguel Torres, the president of Bodegas Torres, the country’s largest winemaker, headquartered in Catalonia. “In the last four years, temperatures have increased 1 degree [Celsius] in the vineyards,” he says. “The quality has not changed so far. Our concern is for the future. They say the temperature could go up 2 degrees — or 5 degrees. So we are moving vineyards from sea level to central valley, and from central valley to mountain areas.” Ten years ago, Bodegas Torres began planting vines at vineyards in the Pre-Pyrenees mountain range at an elevation of 1,000 meters as a hedge against climate climate change.
Another looming problem lies not in the vines, but culture and tradition. In many European countries including Spain, Portugal, France, and Italy, wine production is governed by “appellation” systems that tie specific wines to their geographical locations. This is based on the concept of terroir, a French term that ascribes a wine’s uniqueness to the soil, landscape, climate, and viticulture practices of the place where it’s produced. A genuine French Sauvignon Blanc must come from Bordeaux, for instance. But as temperatures climb, it will get increasingly difficult to grow the “right” grapes.
Another study by Jones projected that by 2049, Bordeaux will have reached the upper temperature limits for growing red varieties and will be outside the ideal climate for its white grapes. No more Sauvignon Blanc. The appellation system will put growers in impossible situations — even as it disintegrates.
