By Molly Moore
Washington Post Foreign Service
Sunday, September 2, 2007
ROUFFACH, France -- On a cobweb-encrusted rafter above his giant steel grape pressers, Ren? Mur? is charting one of the world's most tangible barometers of global warming.
The evidence, scrawled in black ink, is the first day of the annual grape harvest for the past three decades. In 1978, it was Oct. 16. In 1998, the date was Sept. 14. This year, harvesting started Aug. 24 -- the earliest ever recorded, not only in Mur?'s vineyards, but also in the entire Alsace wine district of northeastern France.
"I noticed the harvest was getting earlier before anybody had a name for it," said 59-year-old Mur?, the 11th generation of his family to produce wine from the clay and limestone slopes of the Vosges Mountains near the German border. "When I was young, we were harvesting in October with snow on the mountaintops. Today we're harvesting in August."
Throughout the wine-producing world, from France to South Africa to California, vintners are in the vanguard of confronting the impact of climate change. Rising temperatures are forcing unprecedented early harvests, changing the tastes of the best-known varieties of wine and threatening the survival of centuries-old wine-growing regions.
In the hot Mediterranean vineyards -- the first to feel the effects of longer, drier summers -- vintners are harvesting grapes at night to protect the fragile fruit at the critical picking stage. Growers in Spain, Italy and southern France are buying land at higher terrains for future vineyards.
Some champagne producers in northern France -- whose grapes were ready for harvest in August, earlier than in any year on record -- are eyeing properties in southern England, the current beneficiary of planet warming. The British wine industry is reemerging for the first time in the 500 years since a mini-ice age cooled Europe.
While Provence and other southern regions of France have suffered through debilitating droughts and high temperatures for several seasons, scientists and growers have been stunned by the dramatic evolutions in the northernmost regions of Alsace and Champagne, long considered less susceptible to global warming.
"Usually Alsace is one of the last regions to harvest in France, and this year we were the first ones," said G?rard Boesch, president of the Alsace Wine Association. "That's astonishing. Vintners wonder how all this will turn out in a few years."
In a chain reaction of nature, climate change is also sending new insects and diseases north. The leafhopper is migrating north with warmer weather, spreading yellow leaf disease in Alsace vineyards for the first time, according to a regional research institute.
Scientists and vintners say wine grapes are the best agricultural measure of climate change because of their extraordinary sensitivity to weather and the meticulous data that have been kept concerning the long-lived vines.
"The link of wine to global warming is unique because the quality of wine is very dependent on the climate," said Bernard Seguin, an authority on the impact of global warming and viniculture at the French National Agronomy Institute. "For me, it is the ultimate expression of the consequences of climate change."
Nowhere is the impact more acute or better documented than in France. Here, the $13 billion wine industry is not only crucial to the economy but also more inextricably entwined in the culture and heritage of the people than in any wine-producing country on earth.
For centuries, the "vendange," or annual grape harvest, has been treated as a near-religious ritual, with parish churches maintaining meticulous records in dusty, crumbling ledgers.
In France, wine growers are subject to the world's most rigid cultivation restrictions: Vintners can grow only varieties authorized for their region, harvests are tightly regulated and, until this year, no irrigation was allowed. Year after year, the climate is the single greatest variable in France's wine production, making its vineyards the perfect climate-change laboratory for scientists.
Ren? Mur?'s family has been growing grapes and producing wine in the hills surrounding the picturesque village of Rouffach since 1648. The family tree, with its 12 generations of wine growers -- Ren?'s children, V?ronique, 31, and Thomas, 27, are the newest Mur? vintners -- is tacked to a wall in his cellars, which produce 350,000 bottles of wine a year.
The wines are aged in 100-year-old oak barrels personalized by Mur?'s grandmother with the names of famous French women, including Marie Antoinette and Joan of Arc.
In 1932, his grandfather bought the 37.5-acre Domaine du Clos St Landelin, named for the abbey whose monks tilled the vineyards in the 8th century. Its sunny, southern exposure on the steep mountain flanks made it one of the choicest vineyards in the area, and it produced the Mur? family's finest wines.
Mur? and other French vintners have tasted global warming in their wines for the last three decades. They liked what they tasted. Their red pinot noirs were more aromatic, and their white Gewurztraminers were sweeter with fragrances of litchi and roses.
All over France, vintners abandoned their forefathers' practice of adding sugar to the wines to improve their flavors and alcohol content. The sun and warmer summers were doing the job for them. Through the 1980s and 1990s, French wines won higher and higher ratings from domestic and international wine critics.
But the climate warming has accelerated faster than vintners or French scientists anticipated. That has forced sugar levels, and consequently alcohol levels, higher in the wines. Some producers in Provence are adding acidic compounds to their wines to keep them from becoming too sweet and undrinkable.
Vintners in Alsace are now facing similar problems. The average temperature in Alsace, which is bordered by the Rhine River and Germany, has risen 3.5 degrees in the last 30 years -- a dramatic increase for sensitive grapevines, according to the French National Agronomy Institute.
"For 10 years, our problem has been to keep the acidity," Mur? said. "Wines need to be balanced to have fresh, crisp flavor."
Mur? has already started changing the way he cultivates his grapes, growing some vines closer to the ground with fewer leaves in the style of southern grape growers, giving his vines less exposure to the sun.
He wants to experiment with growing southern Syrah grapes in Alsace. The way Mur? sees it, if the southern climate is moving north, he should be prepared to grow grapes that can withstand the heat.
"We have to stay in contact with the climate and the 'terroir,' " said Mur?, tromping between the rows of leafy vines heavy with the last of this year's purple pinot noir grapes. "We have to adapt. It's a question of survival."
"Terroir" is an ephemeral French description of the soil, slope, climate and locality that give each wine label its unique flavor and aroma.
But Mur? is discovering that the regimentation of the French wine production system that has allowed climate change to be documented so accurately is now threatening to undermine the very industry it was designed to protect.
Before he can plant the experimental grapes, Mur? must obtain the permission of the powerful Alsace Wine Association, watchdog of the region's viniculture reputation and tradition. Without its approval, said his daughter, V?ronique, planting different grapes would be "as illegal as planting marijuana" under French wine laws.
"Of course, we have to adapt to climate changes," said Boesch, the association president and a wine grower. But he added, "We have to preserve our identity. Our identity is not Syrah, it's Riesling.
Scientists warn that climate change is advancing too rapidly for the cumbersome French wine bureaucracy.
"Some vintners, like Ren? Thomas, are ahead of others," said Philippe Kuntzmann, a grapevine specialist at Interprofessional Technical Center for Vines and Wine in the Alsace regional capital of Colmar. "Others are more traditional; they want to wait and see. If you wait too long, it will be too late."
Mur?'s daughter, who studied agronomy and biology in college, said she sees change as the only way to pass the Mur? heritage on to her 2 1/2 -year-old daughter, Margaux (as in the wine), and the son she is expecting to deliver in November.
"Yes, it's a radical idea," she said. "We don't say tomorrow we'll get rid of pinot noir and replace it with Syrah. It takes years and years to see the results in winemaking. We think it will be investing in the future to have this experiment."
Researcher Corinne Gavard contributed to this report.