In Vino Veritas
The delicate wine grape has become our best early-warning system for the effects of global warming.
A handful of climate-savvy winemakers such as Graves are trying to rouse their colleagues to action before it is too late, but to little avail. Indeed, some winemakers are actually rejoicing in the higher temperatures of recent years. "Some of the most expensive wines in Spain come from the Rioja Alta and Rioja Alavesa regions," Pancho Campo, the founder and president of the Wine Academy of Spain, says. "They are getting almost perfect ripeness every year now for Tempranillo. This makes the winemakers say, 'Who cares about climate change? We are getting perfect vintages.' The same thing has happened in Bordeaux. It is very difficult to tell someone, 'This is only going to be the case for another few years.' "
The irony is, the wine business is better situated than most to adapt to global warming. Many of the people in the industry followed in their parents' footsteps and hope to pass the business on to their kids and grandkids someday. This should lead them to think further ahead than the average corporation, with its obsessive focus on this quarter's financial results. But I found little evidence this is happening.
The exception: Alois Lageder's family has made wine in Alto Adige, the northernmost province in Italy, since 1855. The setting, at the foot of the Alps, is majestic. Looming over the vines are massive outcroppings of black and gray granite interspersed with flower-strewn meadows and wooded hills that inevitably call to mind The Sound of Music. Locals admire Lageder for having led Alto Adige's evolution from producing jug wine to boasting some of the best whites in Italy. In October 2005, Lageder hosted the world's first conference on the future of wine under climate change. "We must recognize that climate change is not a problem of the future," Lageder told his colleagues. "It is here today and we must adapt now."
As it happens, Alto Adige is the location of one of the most dramatic expressions of modern global warming: the discovery of the so-called Iceman—the frozen remains of a herder who lived in the region 5,300 years ago. The corpse was found in 1991 in a mountain gully, almost perfectly preserved—even the skin was intact—because it had lain beneath mounds of snow and ice since shortly after his death (a murder, forensic investigators later concluded from studying the trajectory of an arrowhead lodged in his left shoulder). He would not have been found were it not for global warming, says Hans Glauber, the director of the Alto Adige Ecological Institute: "Temperatures have been rising in the Alps about twice as fast as in the rest of the world," he notes.
Lageder heard about global warming in the early 1990s and felt compelled to take action. It wasn't easy—"I had incredible fights with my architect about wanting good insulation," he says—but by 1996 he had installed the first completely privately financed solar-energy system in Italy. He added a geothermal energy system as well. Care was taken to integrate these cutting-edge technologies into the existing site; during a tour, I emerged from a dark fermentation cellar with its own wind turbine into the bright sunlight of a gorgeous courtyard dating to the 15th century. Going green did make the renovation cost 30 percent more, Lageder says, "but that just means there is a slightly longer amortization period. In fact, we made up the cost difference through increased revenue, because when people heard about what we were doing, they came to see it and they ended up buying our wines."
The record summer heat that struck Italy and the rest of Europe in 2003, killing tens of thousands, made Lageder even more alarmed. "When I was a kid, the harvest was always after Nov. 1, which was a cardinal date," he told me. "Nowadays, we start between the 5th and 10th of September and finish in October." Excess heat raises the sugar level of grapes to potentially ruinous levels. Too much sugar can result in wine that is unbalanced and too alcoholic—wine known as "cooked" or "jammy." Higher temperatures may also increase the risk of pests and parasites, because fewer will die off during the winter. White wines, whose skins are less tolerant of heat, face particular difficulties as global warming intensifies. "In 2003, we ended up with wines that had between 14 and 16 percent alcohol," Lageder recalled, "whereas normally they are between 12 and 14 percent. The character of our wine was changing."
A 2 percent increase in alcohol may sound like a tiny difference, but the effect on a wine's character and potency is considerable. "In California, your style of wine is bigger, with alcohol levels of 14 and 15, even 16 percent," Lageder continued. "I like some of those wines a lot. But the alcohol level is so high that you have one glass and then"—he slashed his hand across his throat—"you're done; any more and you will be drunk. In Europe, we prefer to drink wine throughout the evening, so we favor wines with less alcohol. Very hot weather makes that harder to achieve."
There are tricks grape growers and winemakers can use to lower alcohol levels. The leaves surrounding the grapes can be allowed to grow bushier, providing more shade. Vines can be replaced with different clones or rootstocks. Growing grapes at higher altitudes, where the air is cooler, is another option. So is changing the type of grapes being grown.
Mark Hertsgaard has written about climate change for outlets including The New Yorker, Vanity Fair, Time,and The Nation. A fellow of the New America Foundation, he has authored six books, including HOT: Living Through the Next Fifty Years on Earth.