Climate Change and Wine
This article discusses some of the ways that global warming effects wine production.
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
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.
I find these discussions a little distasteful really. When I was a kid in a pre-septic-tank country town "phenol" was the vile smelling stuff we used to put in the backyard dunny when it started to get a bit on the nose.
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 the most important is growing the right varieties for the local environment. Other factors include row orientation, 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 several recent years where the vintage in Australia was abnormally early due to the warmer growing season.
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.
Keep in touch with Vinodiversity
Just enter your details below and you will receive an occasional newsletter letting you know all about the alternative varietal wine scene in Australia and beyond.