Climate Change and Wine -How will global warming change Australian wine? We are hearing plenty about global warming lately. The media is full of discussion about emissions trading, carbon offsets and food miles. At long last the politicians seem to have picked up that it is an important issue.
The issue of climate change impacts on wine in a number of ways. - Like all agriculture based industries wine is a producer of greenhouse gases such as carbon dioxide
- Changes in climate have effects on viticulture and winemaking
- The industry and wine consumers can contribute to the solution of some of the related problems
This article discusses some of the ways that global warming effects wine production. Wine is a complex substance. A good wine is the result of an intricate process with many factors influencing the bouquet, the flavour, the longevity and the enjoyment of each bottle. That's why every wine is different; that's why we love the stuff. Vintages vary from year to year. Wines from different regions vary, even if made from the same grape varieties.
A major influence on wine quality is the temperature during few weeks before ripening. If it's too hot the grape makes lot's of sugar and no flavour compounds; too cold and there won't be enough sugar or flavouring compounds to make good wine.
Much of the quality of a wine depends on a group of substances called polyphenols, or phenolics. You'll hear wine buffs rabbiting on about them from time to time.
Anyway phenolics are very important in wine. They include the colour and flavour compound and the tannins which help to give the wine body. The problem is the phenolics are produced at a different rate to the sugar. Having your grapes reach phenolic ripeness and the right level of acidity and grape sugar is the elusive simultaneous 'big O' for grapegrowers. This is easier to do in cooler climates, in warmer climates things tend to come just a bit prematurely if you get my drift.
Grape growers and winemakers have all sorts of tricks to try to manipulate these effects, growing the right varieties for the local environment, trellising systems, leaf picking etc.
What's all this got to do with climate change? Well lots actually. As things get warmer we might see grapes ripen very quickly. This certainly was the case in 2007 where the vintage in Australia was abnormally early due to the warmer growing season. Unusually early vintage was a recurrent theme when I collected a few reports about that vintage at
www.squidoo.com/2007vintage. At the moment I'm putting together some notes about the 2008 vintage in Australia It's based on web news articles and comments by winemakers, but you may wish to leave a note there as well.
If the trend to warmer summers in Australia continues we might see some changes. Existing wine regions will have to consider using different varieties. Viticulture will gradually migrate to what are now cooler areas at higher altitudes or towards the poles.
Australia's industry is much better placed to change, our tradition is for innovation. The French for example are more conservative and their appellation system much more restrictive.
I'm an optimist. The industry in Australia will adapt. For the past 20 or so years a huge amount has been done in modernizing and diversifying the Australian wine industry. We have new varieties, new clones, new vineyard management systems, new wine regions and new winemaking technologies. We've even got new closures to replace those dodgy corks! But most importantly we have plenty of new talent as winemakers are better trained and imbued with an innovative attitude.
Darby Higgs is a Melbourne based writer with an interest in Australian wines made from less common grape varieties. He has written an ebook about food matching with sangiovese www.vinodiversity.com 
