Reaching for a Cold One

 Photo: BBC used with permission

Photo: BBC used with permission

I’ve never met a winemaker who doubted the reality of climate change – like everyone who works in agriculture, winemakers (and especially those who grow their own grapes) see the effects of a warmer climate increasing every year. On the one hand, growers in what were once marginal areas are happy, but those in what were once considered classic areas are becoming worried. What’s happening?

Grapes and a relatively delicate crop. The vitus vinifera grapes that produce most of the world’s table wine thrive in two narrow bands around the globe – from 30 degrees north of the equator to 50 degrees north of the equator, and from 30 degrees south of the equator to 50 degrees south. Venture further south in the southern hemisphere or further north in the northern hemisphere, and the temperature is too cold to allow even the hardiest grape to ripen. The opposite situation exists going the other direction – it’s too hot for grapes to produce good juice for wine.

With global warming, the boundaries are shifting – once marginal areas like the south of England are now on the cooler edge of the climate-revised growing zones. As grapes get riper, sugar goes up, but the acidity in fruit goes down (think of how a green apple is tart but a red apple is sweet). Thus, Champagne, at 49.7 degrees north of the equator and so right on the edge of the traditional boundary, is now worried that their grapes are getting too ripe to provide the kind of acidity that gives their effervescent wine its racy verve. 

 The all-important barley crop (Photo: Public Domain via Wikipedia Commons)

The all-important barley crop (Photo: Public Domain via Wikipedia Commons)

This may seem rather esoteric to many wine lovers, but a real-world awakening is about to come. A California-based winemaker friend of mine once told me, “it takes a lot of beer to make a great wine,” as she lifted a frosty mug after a long day in the vineyard. Beer lovers may feel the heat of climate change before wine-only drinkers, according to a new study published earlier this week in the journal Nature Plants. Nathan Mueller from University of California – Irvine, one of the authors of the study, told Forbes, "Our results show that in the most severe climate events, the supply of beer could decline by about 16 percent in years when droughts and heat waves strike. That's comparable to all beer consumption in the U.S.” In other words, Mueller continued, “Future climate and pricing conditions could put beer out of reach for hundreds of millions of people around the world." Estimates are that in Ireland, for example, beer prices will go up somewhere between 40 and 300 percent.

This terrifying outlook is based on estimates of what climate change will do to barley crops around the world – most barley is cultivated as animal feed, but it is also a crucial grain in beer production. It is essential as well in making Scotch whisky, so I’m doubly worried now, and I’m not alone. Steven Davis, another of the study’s authors, put thing in perspective. "The world is facing many life-threatening impacts of climate change, so people having to spend a bit more to drink beer may seem trivial by comparison," Davis said. "But there is definitely a cross-cultural appeal to beer, and not having a cool pint at the end of an increasingly common hot day just adds insult to injury."