When we talk of climate change and wine, we are really addressing the increasingly erratic weather patterns within an overall warming trend. Vintage variation has always been a hallmark of the finest European vineyards – but enough is enough, when a Côtes du Rhône, or Languedoc producer is hit by a freak hail storm in May, after budburst and loses 30% of her crop and then is hit by drought in August and loses another 10%, that is no longer climate variation – that is a climate risk too hard to bear.
And for the grapes that do survive, higher temperatures, especially at harvest, mean more sugars in the grapes, which means more alcohol in the wine once fermented. Christian Seely, Managing Director of AXA Millésimes, opened the first international symposium on “Alcohol Levels Reduction in Wine” in 2013 with these remarks:
“The increase in alcohol level related to climate change is one of our major challenges. This phenomenon observed all over the planet shows that grapes ripen more and more early, and would mainly result from global warming. It is now common to see quality wines with an alcohol by volume (ABV) of 13, 14 or even 15%. Since the eighties, each ten years, alcohol levels gained almost 1% with an average increase of 2 to 3%, if not more. This historical surge of ABV was measured in many countries: in the South-west of France, 15 years ago, the average alcohol level amounted to 11%; it now ranges between 13 and 14%. In Australia, the average was 12.4% in 1984; in 2004 it reached a striking 14%. In California, the average ABV was 12.5% in 1978 and soared to 14.8% in 2001.”
Today, they are even higher.