Wine and climate change: a well-matched cup-le?

The rise in mercury and an increase in plagues are changing the face of wine cultivation. Vine-growers in Navarre and La Rioja have brought their grape harvest forward by two weeks this year.

All over the planet, grapes are being affected by climate change: A rise in temperatures means the fruit is ripening earlier and earlier with vine-growers year on year having to bring forward the harvest.

According to Navarre's Wine Culture and Oenology Station (EVENA) picking for this year's crop has been brought forward by two weeks compared to last year. However, at least for the minute these gradual changes are not affecting the quality of the grape. On the contrary, EVENA has declared that this season it foresees an increase of 10.9% on the number of grapes harvested last year. Rioja's Regulating Council for the Guarantee of Origin, for its part, has also confirmed that "to date, the current state of the vineyards is very good".

Even if wines from the Iberian Peninsular have still not been greatly affected, alarm bells are starting to ring among oenologists the world over. A study by the University of Southern Oregon in the US confirmed that a rise in the planet's temperatures was causing changes to the grapes' natural cycle of maturity. The world's major wine producers are starting to call on their governments for help in slowing down the alterations. In France, wine experts warn that, should temperatures continue to rise, wine-producing areas will have to be moved 1,000 kilometres north, leaving entire regions completely destitute.

Rise of 1.5ºC

The ripening of grapes depends on factors such as area, climate and the style of the wine. According to a report published midway through 2009 by Greenpeace, over the past five decades the average temperature on the Peninsular has risen by 1,26ºC. Should the temperature rise by a further 1.5ºC, grapes would begin to reach maturity three weeks earlier than they should, leading to "the loss of some essential characteristics," according to the environmental organisation. This rise in temperatures is the reason for which wine production has already begun to relocate; Patagonia in Argentina, for example, is being considered the new "promised land" given its favourable environmental characteristics for (cultivating) wine.

When a grape matures too early, there is insufficient time for all its qualities to take hold, such as those relating to colour and taste. For this reason, the grape is picked when it is low in acidity but high in alcohol. "When acidity drops but the level of potassium rises, the wine is less fresh, more sickly and at higher risk of contamination," explains Pancho Campo, president of the Wine Academy, an organisation which every year brings together Oenologists from the world over to meet at the World Congress on Climate Change and Wine in Barcelona, where they exchange their experiences.

Another consequence of the temperature-rise is the greater resistance of plagues in the vineyards. In the absence of cold, plagues are able to thrive therefore wreaking greater havoc in the wine production process. The long-term lack of water is also the cause of many headaches for oenologists. Experts warn of a major reduction in uncontaminated water should the international demand continue to rise in the face of less frequent rainfall and ever-reducing ice-caps.