How climate change is changing Australian wine
Australia’s most popular varieties suited to cooler climates – shiraz, chardonnay, cabernet sauvignon, pinot noir and sauvignon blanc – may not be as easy to grow as temperatures rise, he adds.
Rainfall also plays an important role in wine production. Since 1970, rainfall in south-west Australia from April to October has fallen by 16%, while in the south-east, rainfall has fallen by 12% in the same months since the 1990s. In the future, rain events are expected to become more intense, aggravated by climatic factors like La Niña and an atmosphere that can hold 7% more humidity for each degree of warming.
“We would have [weather] events – and this is where they talk about climate change – you expect to see once every 10 years, you could have a bad freeze or a really wet year,” says Chambers. “We now get them back to back or more frequently.”
Dr. Christopher Davies, CSIRO team leader at Agriculture and Food, says hail, unseasonal rain and temperature fluctuations present a challenge for wine producers. They can lead to an increase in botrytis (which discolours wine from red to orange) or mold which affects photosynthesis and reduces wine quality.
For NSW’s Hunter Valley, Wine Australia’s Climate Atlas analysis found that average rainfall during the 2081-2100 growing seasons is expected to be around 55 millimeters higher than the 1997-2017 average. Temperatures over the same period are expected to rise by 3 degrees. Similar changes are expected at Mudgee and Orange.
By contrast, in Victoria’s wine region of Rutherglen, average rainfall over these growing seasons will be 20 millimeters below the 1997-2017 average. Temperatures are expected to climb 3.4 degrees over the same period. In the Yarra Valley, average rainfall could decrease by 66 mm, while temperatures are expected to increase by 3 degrees.
Prior to 1998, the Chambers’ 25-hectare property was not irrigated at all, relying on annual rainfall. “Have been [now] highly dependent on irrigation to keep the vines healthy and viable throughout the heat period.
Adaptation and mitigation
Dr Liz Waters, Managing Director of Research, Development and Adoption at Wine Australia, says the industry has been adapting to climate change for over a decade: “The beauty of wine is that it reflects the region in which it is grown and [its] climate.”
The goal for the industry now is to continue to evolve to meet new challenges. Growing varieties that are better suited to warmer climates is just one strategy.
NSW Wine Industry Association chairman Mark Bourne said varieties from the Mediterranean are better able to hold their acid in extreme heat and withstand drier conditions. Italian white wine fiano and tempranillo, a Spanish variety that yields a full-bodied red, have become more popular in recent years for this reason and people are willing to pay for them, he says. (The Chambers vineyard now includes Tempranillo.)
In the Central Highlands region of NSW, See Saw Wine co-owner Justin Jarrett has vineyards at 700m, 800m and 900m above sea level to capture a range of different climates. For every 100 meters, the temperature increases by about 1 to 1.5 degrees, he says.
When Jarrett and his wife Pip started their winery 25 years ago, they grew Sauvignon Blanc and Riesling grapes in the lower vineyard and found that the same grapes in the upper vineyard were not thriving. But as the years passed and the climate warmed, the couple stopped using the 700-meter vineyard for their white wine, which now prefers the higher altitudes.
The other notable change is that the harvest season has been reduced from 8-12 weeks to six.
“Harvest time is the time of joy for all farmers, it’s when you look at your year’s work and say to yourself, ‘wow, we made it,'” Jarrett says.
“You think to yourself, ‘if I can sustain this for the next 20 years, it will be very exciting’… But what you see today cannot be what will happen in 20 years.”
The couple have started growing other types of crops between the vines, such as turnips and peas to increase carbon in the soil, and are determined to make the business carbon positive in the years to come.
“If you’re not sustainable, consumers won’t drink”
Despite growers’ efforts to introduce new varieties, one key factor remains beyond their control: consumer tastes.
Australians don’t yet know fiano, albarino or tempranillo as they do with shiraz or sauvignon blanc. Davies says what’s particularly interesting about Australians’ drinking habits is that they’re more drawn to grape variety and region, rather than winery. This is at odds with most European consumers, who tend to care about chateau or vintage.
But the industry is confident the new range of strains is something consumers – especially younger ones – will embrace with open arms, especially if they know it has been sustainably produced.
“Consumers actually want us to start making this change. They look at your brand values,” says Battaglene. “If you’re not looking to become sustainable, consumers won’t drink your product.”
The national wine industry is developing an emissions roadmap to set achievable reduction targets and help the industry achieve them. The sector aims to have net zero carbon emissions by 2050, but wants to get there sooner than that.
For Chambers, the focus on sustainability is more than just a marketing ploy: [where] someone’s word is no longer good enough. You must have another certification to potentially save these comments. People are aware of greenwashing issues.
Chambers Rosewood is working to achieve certification, which Chambers says is a formalization of practices it has already implemented.
For his part, Jarrett remains hopeful for the future of the wine industry. “In Australia the agriculture industry has been a great adapter and I think we will continue to be,” he says. “We have these [climate] problems… but what matters is what we are going to do about it.
When asked what his favorite wine is, he laughs as he asks, “What’s your favorite child?”
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