Global Warming: Too Much of a Good Thing for Wine?

Warm WineThis article appearded in the August/September 2006 edition of Connections Magazine (Ireland) It must be getting hot in California wine country. Randall Grahm, rock-star winemaker of Bonny Doon fame, was scouting out vineyards in southern England. England? I was driving around West Sussex earlier this year hoping to visit one of England's best known vineyards. Not being able to find it, I stopped and asked some of the locals for directions. “A vineyard? Have you tried France?” I have to admit they have a point. England isn't exactly known for its wine. Not yet anyway. Global warming may still be a political issue for a shrinking few but to winemakers such as Randall Grahm it's a very real concern that needs to be addressed. So let's get real. This article is not just about rising temperatures, rising oceans, changing ecosystems, species extinctions etc. It's about something of graver concern: the quality of the wine we drink! Not since phylloxera, the vine pest, began killing all of Europe's vineyards in the 1860's has there been such a global problem for winemakers. So far it hasn't been so bad. According to recent research (see table), average growing termperatures in the world's high quality wine regions have increased 1.26°C in the past fifty years. This increase has certainly improved wine making in cooler regions. Warmer weather means riper grapes which leads to less green or raw flavours, higher alcohol levels in the wine (converted from sugars during fermentation) and lower acid levels. Picture eating an unripe apple to get a feel for how bad a wine unripe grapes can make: unpleasantly sour or tart due to the extremely high acidity and low sugar levels. Cool regions like the Loire Valley used to struggle just to get 10% alcohol for its red wines in the 1950's. Just imagine how thin and weedy they must have tasted! They've definitely benefited from the warming trend as well have cooler regions such as Burgundy, Bordeaux and Germany.
Average Growing Season Temperatures (°C) in Selected Wine Regions

Past Present Future

1950 2000 2050
Mosel Valley 12.07 13 14.51
Alsace 12.16 13.1 14.75
Champagne 13.63 14.5 16.01
Rhine Valley 13.97 14.9 16.41
Norther Oregon 13.93 15.2 16.76
Loire Valley 14.29 15.3 17.44
Burgundy -Côte d'Or 14.24 15.3 17.39
Beaujolais 14.56 15.8 18.06
Chile 15.19 16.3 18.14
Eastern Washington 14.69 16.5 19.31
Bordeaux 15.3 16.5 18.83
Central Washington 14.74 16.6 18.87
Rioja 15.37 16.7 19.22
Southern Oregon 15.63 16.9 19.25
Coastal California 15.41 17 18.85
South Africa 16.58 17.1 17.98
Northern California 15.69 17.4 19.56
N. Rhône Valley 16.36 17.6 19.86
Northern Portugal 16.41 17.7 20.12
Barolo 16.39 17.8 20.21
S. Rhône Valley 16.96 18.2 20.46
Margaret River 17.6 18.6 20.64
Chianti 17.21 18.8 21.1
Hunter Vallery 18.71 19.8 21.58
Barossa Valley 18.95 19.9 21.91
Southern Portugal 18.68 20.3 23.15
Southern California 18.97 20.4 21.78
This chart is based on data from Climate Change and Global Wine Quality, 2005, Gregory V. Jones, Michael A. White, Owen R. Cooper and Karl Storchmann
These winemakers have also had to resort less to artificial manipulations, which in a cool climate means chapitalization and deacidification to balance the wine. Chapitalization is the practice of adding sugar to the grape juice (known as must) just before fermentation to increase the final alcohol levels. It's an allowed practice in nearly all cool regions as long as all the sugar is fermented dry without residual sweetness in the wine. Deacidification is another allowed practice where calcium carbonate (chalk) or a similar substance is added to the wine to lower its acidity. Since these interventions are not needed with riper grapes in warmer years, the resulting wine is naturally balanced. Another benefit is that the fully riped grapes develop more complex flavours. The warm weather has suited warmer climates as well. The riper grapes and the resulting big wines – full bodied, high alcohol – have been getting high marks in publications and in competitions. The reality is that the more subtle wines don't stand a chance next to the biggies in a comparative tasting of 20+ wines, so bigger has literally come to mean better. In a certain way this has always been true in the wine world but how far can this go? Zinfandels in California are now routinely 15 to 17% alcohol, which is exactly the alcohol content of Port, a fortified wine. Are we seeing too much of a good thing? A long growing season in any climate is associated with better wine. The longer a grape stays on the vine, the more richness and flavour complexity it develops. The problem in many warm climates now is that there can be fully developed sugars but unripe skins and seeds a month or so before harvest. So by the time the grapes are picked with ripe skins the sugar level has continued to increase and the acid levels have dropped. Remember the unripe apple? This time think of an overripe apple: brownish, sickly sweet and no refreshing acidity. The increased sugars (and resulting increased alcohol) and low acid levels mean other types of artificial manipulations are necessary for these winemakers. Again, the methods used are both necessary and legal. Tartaric acid is routinely added to balance wines in warm climates. And to lower excessive alcohol levels, the wines are literally diluted with water or dealcoholized with a newly developed apparatus. Everything is currently manageable but growing season temperatures are projected to increase 2.04°C on average gloabally in the next fifty years! Penguin and WineHow can warm climate winemakers continue to adapt? Overall, they have 3 choices: continue artificial manipulations on an increasing level, plant warmer weather grape varieties or move to a cooler climate. We may be seeing more hot weather grape varieties such as Mourvèdre, Syrah, Grenache, (reds) Roussane and Marsanne (whites) replacing cooler weather grape varieties such as Pinot Noir, Merlot, Cabernet Sauvignon, Sauvignon Blanc and Chardonnay. Miles may be force to scrap Pinot Noir for Mourvèdre in Sideways II. Growers who don't want to change grape varieties will have no choice but to move to a cooler location. One way is to head for the hills. The largest wine producer in Spain, Miguel Torres, is currently developing vineyards in the Pyrenees mountains at 900M altitude near his current vineyards in Catalunya. Another way is to head North. Californian vineyards may soon be transplanted in Oregon, Washington or British Columbia. Europeans are looking towards cooler climes in England – as Randall Grahm is considering – as well as Belgium, Ireland and Denmark. Even Scotland and Norway may not be too far off in the future. For summer drinking I also like to head North like so many vacationers and opt for cooler climate wines with their lower alcohol levels and refreshing acidity. White is usually the colour we associate with cool climate wines as red wines are much more difficult to fully develop. Since red wines really are the litmus test in terms of how warm the cooler regions have become and how much they've benefited from increased temperatures, I've chosen 6 reds from a few of the world's cooler wine regions to help illustrate the current situation. Also appropriate for summer, they're quaffable (read: not serious) and benefit from a slight chill in the fridge or ice bucket, 14°C to be exact. Cool Climate Red Wines: 2002 Lingenfelder Dornfelder Fox Label, Pfalz 12.0° £7.19 (Oddbins) 2 Stars Red wines are becoming increasingly popular for Germans and most are consumed locally. This is one reason you won't see much Dornfelder outside of Germany. A grape of humble origins, it was bred in 1955 in Württemberg mainly as a blending partner to add colour to pale German reds. If you've ever tried a German Spätburgunder (Pinot Noir), you'll see why this was desirable. It surpassed all expectations to become the second most planted red variety in Germany after Spätburgunder. This one is a testament to its popularity with sweet juicy berry flavours and rose perfume. Dornfelder is now also made into serious wines fetching high price tags but the Lingenfelder Fox Lablel is simply a highly aromatic, unique and charming wine for the summer. 2002 Mission Hill Five Vineyards Cabernet Merlot Okanagan Valley VQA 13.0° £9.50 (Handford) 2 Stars The Okanagan Valley in British Columbia is actually the northern tip of the Sonora Desert and an excellent micro climate for wine in what is normally considered ski country. This California style vineyard/resort makes a respectable plummy Cabernet Merlot in a fruity, softly oaked California style. 2004 Laurent Martray Brouilly Vieilles Vingnes 12.5° £8.95 (Lea & Sandeman) 3 Stars Beaujolais is in the southernmost part of Burgundy but is still further north than most wine regions and definitely a cool climate for growing wine grapes. Gamay is the main variety here which can make wines that range from fruity Beaujolais Nouveau to more elegant Cru Beaujolais, of which this Brouilly is one. This Vieilles Vingnes (old vines) wine is made is small quantities and is the most subtle of the 6 wines here, with elegant but earthy flavours of red fruits and spice. 2003 Chapel Down Pinot Noir 11.5° £13.50 (Handford, Thameside) 2 Stars The summer of 2003 was hot enough for England temporarily not to be considered a cold wine region anymore and this wine certainly is evidence. It has an excellent and instantly recognizable Pinot Noir nose – aromatic and varietally correct – raspberries, red currants and fall leaves. It may still may pale in comparison with equally priced red Burgundies but is an amazing taste of good things to come from England. 2004 Domaine de la Paleine Saumur 13.5° £6.99 (Handford) 3 Stars Loire Valley reds such as Chinon, Bourgeil and red Saumur have consistantly been panned by Anglo wine writers such as Robert Parker, which also helps to make them a good value. The French and particularly Parisians absolutely do not agree and value them for their refreshing acidity and pungent flavours that make them perfect food wines. Indeed, they are the toast of Paris bistros. This like most Loire Valley reds is made from 100% Cabernet Franc, the main grape in Cheval Blanc. It's a bit more full bodied than most, moderately aromatic with sour cherry and bell pepper notes along with the classic Loire red flavour of pencil shavings. 2004 Zantho Zweigelt 13.5° £8.50 (Handford) 3 Stars Grüner Veltliner's meteoric popularity has put Austria back on the wine map and has boosted recognition of its Rieslings as well. Its reds, however – mainly Blaufänkisch and Zweigelt – have stayed out of the spotlight but are definitely worth seeking out. Could it be that they're difficult to pronounce? Like Dornfelder, Zweigelt [sviy-gehlt] is another red grape bred (in 1922) for cold climates that has exceeded all expectations. The Zantho is pleasantly tart and perfumed with the distinctive taste of black pepper on the palate and a surprisingly long and elegant finish.

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  • Your article on global leaves me puzzled. The reference to a ‘local’ in England betrays an ignorance, or a regional bias. When I spent a summer in southern England I (Kent and
    Canterbury) I visited a number of vineyards, and bought some local wines. As in NYState the English produce a SEYVAL BLANC, a ‘French Hybrid. As in NYS this hybrid grape
    does well in a cooler, shorter growing season. I didn’t like the English SY Bl, too tart as are many in the states.. However, the outstanding Seyval Blanc is produced by CLINTON
    VINEYARDS in the Hudson Valley 70 miles north of NYC.It closely resembles a French Sancerre.I did a 15 year vertical and their were no ‘bad’ years. I prefer to hold it for a few
    years. Clinton makes a great ’Champagne", bright, tasty, out of this grape. It is made in
    the traditional methode champenoise. Linden in Va, an excelleny winery, makes a ’nice Seyval Bl, but is a shadow next to Clinton. By the way, Va has some top notch wineries, notably Pearmund, within easy driving distance wet of DC.

    Arnie Eisen on
  • thanks for the information. It is interesting to consider that Global Warming will change the way crops are grown, really across the globe over time. thanks for the info

    Crystal on
  • Hi Arnie,
    Thanks for the recommendations. I’ve never tried the Clinton Seyval Blanc but it’s definitely one grape that really works very well in cooler climates. The Breaky Bottom Seyval Blanc here in the UK is pretty good.

    Steve De Long on

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