Climate change is already changing the environment of the established “terroirs” of Australian wines, such as the Coonawarra and the Barossa Valley, says Prof Snow Barlow of the University of Melbourne.
But it won’t be the end of winemaking as we know it. Our wines will just evolve.
Prof Barlow has assembled information on harvest dates from vineyards all over Australia going back 100 years or more. He spoke about his findings to the XVIII International Botanical Congress being held in Melbourne this week.
At present, harvest dates are moving earlier by an average of between one and three days a year, he says, “although it’s different in each different region.” And the warming trend is accelerating the process.
Winemakers have a few choices. Either they evolve the taste of their wines to something a little different because of the changing characters of their grapes, or they grow and employ another grape variety, or they change the region where they source their grapes.
“Winemakers also need to prepare for extreme events,” Prof Barlow says. Already vintages in certain regions had been severely affected by sustained heat and bushfires. Some grape growers are now protecting their crops against sunburn or “raisining” using canopy management, leaving the western side down to insulate the rest.
Prof Barlow was relatively optimistic about the future of wine grapes, however. Because vineyards are essentially cloned to reduce variability, he says, “there’s a lot of genetic diversity that plant breeders can call on.”
For more information: call me on 0417 131 977, niall@scienceinpublic.com.au or AJ Epstein on 0433 339 141 or email aj@scienceinpublic.com.au. We’ll be in the Media Room (214 from 8:30am Monday 25 July).
- More botanical stories from the Congress: www.scienceinpublic.com.au/botany2011
- Conference website: http://www.ibc2011.com
- Public events program here: http://www.ibc2011.com/Events.htm