GLOBAL warming may be the latest threat to the wine industry, but a clutch of producers in one of Spain's hardest-hit regions say they have found a way to survive and even profit from it.
Vintners face twin dangers from climate change. Higher temperatures result in grapes containing more sugar and thus more alcohol, but wines packing a heftier wallop are less popular these day, in part because people are more sensible about drinking and driving. Drought can also stop vines from producing fruit altogether.
So wine makers in Spain's south-eastern Murcia region have come up with a way to coax their vines into making a product that retains the character of a classic wine, only with much less alcohol – 6.5% by volume, compared with 14% or more for many traditionally made Spanish wines.
The technique and product are so groundbreaking that the European Union has had to devise a new category – "wine with reduced alcohol content" – for it to be marketed.
"Vineyards are migrating north to avoid heat," said Pedro Jose Martinez, the brains behind the project at the Casa de la Ermita winery, near the town of Jumilla. "If we want to stay in the business, we have to adapt. And this method gives us a means to do so."
His pride and joy, called Altos de la Ermita, is redolent of cherries, plums and blackberries, with a smoky hint of the oak barrels in which it spends six months maturing. It tastes light and fruity, like a good summer drinking wine. Only a slight lack of 'legs' – tear-like traces wine leaves on the side of a glass – gives away the low alcohol content.
"You can drink two good glasses with your lunch and still be under the legal limit," said the project's chief wine maker, Marcial Martinez – no relation.
The winery says it knows of no other producers making this kind of wine, but it expects competition to emerge. It plans to release 770,000 bottles of Altos in this, the debut year, and 1.5 million in 2009, with sales planned in Spain and around the world.
Much is at stake in Spain's slice of the global warming crisis. Its wine industry posted ?5.7bn (4.5bn) in revenue in 2006, according to the Spanish Wine Federation, and employs 400,000 people. No other country has so much land dedicated to growing grapes.
Most wine-producing areas in Spain have changed little in appearance in 3,000 years, since eastern Mediterranean traders such as the Phoenicians first introduced staples including olives, almonds and grapes.
Wine regions such as La Mancha and Murcia face pressure from several sources: changing consumer preferences; new laws to cut the road-accident death toll; and EU legislation aimed at reducing overproduction.
'Hot country' wines such as those of southern Spain, with levels as high as 15% alcohol, are no longer popular in the world's trendy wine shops. Gone are the days when wine lovers enjoyed heady, oaky wines typical of the late 1980s and 1990s. The pendulum has swung the other way, and today people prefer lighter styles, such as French Bordeaux with 13% alcohol.
But it is rising temperatures and drought that are worrying vine farmers most. Records show Spain is experiencing its driest year since records began 60 years ago.
"We are getting higher alcohol levels because of hot weather and excessive evaporation from the grapes," said Jorge Garcia, manager of the Vitivinos co-operative winery in Villamalea on the south-eastern fringe of La Mancha, the world's largest wine-producing region, according to the United Nations Food and Agriculture Organisation.
"Producers are leaving wine making for mushroom cultivation and edible rabbit breeding," said Garcia, as a whiff of mushroom compost drifted from low-built white buildings dotting fields where vineyards once thrived.
Juan Manuel Gomez, agriculturalist at Casa de la Ermita, said it had not rained in his area since October. Luckily, the vineyard has a spring for drip irrigation. But areas unable to irrigate "are almost certainly doomed to give up wine production", he said.
The Ermita vineyard's technique uses carefully controlled irrigation to trick vines into making grapes with less sugar, and thus significantly less potential for alcohol. The finished wine is put through rotating cones to separate out alcohol molecules. It is this step that made it necessary for the EU to devise a new category of wine.
"We manage to achieve a product that retains all the sensorial characteristics of a classic wine, but with only 6.5% alcohol," said Marcial Martinez.