Meltdown in your wineglass?

THE “post-classic” era of winemaking is dawning, according to experts at the second Climate Change & Wine conference in Barcelona, Spain, at the end of last week. And it’s going to be full of nasty surprises.

What might “post-classic” wine be like? Scientists told winemakers and other industry professionals at the gathering to expect natural acidity to drop, colors to fade and alcohol levels to rise. Aromas could vanish. In short, wine may gradually lose the complexity wine lovers appreciate. And as rising levels of carbon dioxide encourage out-of-control vegetative growth, the green, herbaceous flavors consumers deplore may well increase.

With so much potential human misery predicted as a result of climate change, “it’s almost frivolous to think about wine in the same context,” said Australian viticulture consultant Richard Smart. “Wine, however, is an early warning signal of what is to come,” he said. “Wine’s past will no longer be relevant [in predicting its future] within 50 years. In only 10 years, the palate of our wines will change.”

Attending the conference were 350 people from 36 countries, a five-fold increase from the 70 participants at the first Climate Change & Wine conference held two years ago, also in Barcelona. Former U.S. Vice President and Nobel laureate Al Gore was the closing speaker via satellite teleconference.

The warming global climate, thus far, has been good news for winemakers in some parts of Europe, where recently, year after year of optimal conditions for grape ripening has made the phrase “vintage of the century” an annual marketing slogan in Bordeaux.

But if warming trends continue (an average temperature increase of 2 to 3.5 degrees Fahrenheit by 2100 is predicted), even in those regions, growing conditions will slide from that peak of perfection into what could become an overheated enological disaster, scientists said.

The first Climate Change & Wine conference advanced the argument that the Earth is warming and, in the process, changing the character of wine. Speakers at last week’s event (organized, as was the first, by Wine Academy of Spain president Pancho Campo) went further, offering new details about the specific changes that can be expected in wine production and suggesting how the wine industry should respond. The lineup included celebrated international winemakers such as Jacques Lurton, a renowned French winemaker with projects in France, Chile, Argentina and Australia. Joining Lurton were influential German winemaker Ernest Loosen, former Château Cos d’Estournel owner Bruno Prats who now produces wine in South Africa and Portugal, and star Spanish vintner Miguel Torres.

Shifting flavor profiles

PRATS and Lurton predicted that, in Bordeaux, Merlot vineyards increasingly will be replanted with Cabernet Sauvignon, Petit Verdot, Malbec and Cabernet Franc, Bordeaux varieties that do better in warmer weather. The flavor profile of Bordeaux will change with the loss of Merlot, said Lurton, “but these are still the traditional grapes of the region.”

Along Germany’s Rhine Valley, Loosen said he expects more Cabernet Sauvignon and Syrah to be planted. If he hopes to continue making traditional Riesling in Mosel Valley, he’ll have to plant new drought-resistant rootstocks that preserve natural acidity. Vineyard classifications in Germany will probably shift. Grand cru vineyards treasured for their ability to produce ripe fruit may be downgraded to mere village status because they will produce over-ripe fruit. In Mosel, cooler east-facing vineyards in the region may be the new sweet spots.

Several speakers suggested that rising alcohol levels will have to be controlled most likely by using methods such as reverse osmosis. To capture natural acids and aromas, harvests will be staggered, with some grapes harvested under-ripe to produce lots that can be blended with fuller-flavored lots from riper grapes. Together, the lots may produce a balanced wine.

Lurton said Europe will need to relax its regulations regarding irrigation. He and Torres advocate irrigation during hot weather, a common practice in American vineyards that is outlawed in many European regions. Torres told the gathering that he is investing several millions of dollars in research to find other ways to mitigate the effects of climate change on Spanish wine.

Research might focus on finding solutions to such problems as thriving populations of new insect pests, increased levels of volatile acidity and brettanomyces (a spoilage yeast), excessive vine vigor and sunburned grapes. Meanwhile, forward-looking wine producers, including Torres, are also investing in land in cooler climate areas.

Eventually, the global map of viable winemaking regions will shift toward the poles, northward in the Northern Hemisphere and southward in the Southern Hemisphere. Warm vineyards in today’s warmest areas, such as those in California’s Central Valley, may be abandoned. And new parts of the globe including England, Denmark, Belgium and the Patagonia regions of Chile and Argentina will emerge as high-quality producers.

New premier regions

THE narrow coastal regions where cool ocean breezes provide relief from rising temperatures, including Russian River Valley, Tasmania and Puget Sound, will be premier wine areas -- along with high-elevation deserts in places as different as China and Arizona.As for such seemingly self-defeating practices as the wine industry’s fuel-burning worldwide shipments of heavy glass bottles, for example, some in the industry are developing more environmentally sensitive alternatives, such as lightweight plastic containers. “We have to be able to hold our heads up on our packaging,” Smart said.

Whoa! Screaming Eagle in a bag-in-a-box container? Not while international wine consultant Michel Rolland counts that Napa Valley winery among his clients. The naysayer at the conference, Rolland dismissed concerns about climate change. “Perhaps the warming will stop? We don’t know,” he said. “So far, climate change has been very good for us.”

Rolland shrugged off the hand-wringing and dark forebodings that dominated the Barcelona event and instead lead a blind tasting of wines that offered a diversion from the main agenda. What do American vintners say about climate change? It was impossible to say from the conference. Only half a dozen Americans attended; there were no American vintners on any of the panels, although Campo issued invitations to representatives of American wine trade associations. It is an American, however, who is leading the research into the effects of climate change on the wine industry. Gregory Jones, a climatologist at Southern Oregon University, has partnered with Hans-Rainer Schultz, a climatologist with Germany’s Geisenheim Research Institute, to produce the bulk of the data that conference speakers used to bolster their arguments. Though Jones said scientists in New Zealand, South Africa, Argentina, Australia, Italy and Portugal have contacted him about conducting similar research in their countries, little follow-up research has been published.

Jones and Schultz’s data show that throughout the world’s wine-growing regions, average temperatures, particularly at night, are rising, and rainfall patterns are increasingly unpredictable. As a result, the grapevine’s growth cycle has escalated so that “bud break,” the start of the annual cycle, occurs as much as a month earlier than it did 50 years ago.

“It’s a disturbance in the balance we call terroir,” Schultz told the group. “The wine industry has tremendous adaptive capacity. But it must agree there is an issue and develop clear strategies for dealing with it.”

corie.brown@latimes.com