Winemaking adapts in face of changing climate

With warmer winters and more extreme weather conditions occurring more often, Canadian grape growers, wine producers and scientists are turning their attention to finding the best ways to adapt.
Winter temperatures are increasing in Niagara, where a microclimate on land near Lake Ontario has helped a grape and wine industry flourish. (Janet Davison/CBC)

Maybe icewine will be produced in new areas across Canada. Maybe winemakers will try their hand at drying grapes artificially off the vine. Or perhaps vineyards will pop up in areas not known as wine regions.

In the face of changing climate conditions, Canadian grape growers, wine producers and scientists are turning their attention to finding the best ways to adapt.

Climate change can be a controversial topic for some folk, but not for those at the Cool Climate Oenology and Viticulture Institute at Brock University, deep in the heart of Ontario's Niagara wine region.

They say they have seen a definite pattern in Canadian weather statistics: a gradual warming trend of a few degrees, alongside more extreme and variable conditions. And that has led their research into two distinct areas.

"One is what can we do in the vineyard to adapt to what looks to be very variable and very challenging weather," says research scientist Gary Pickering.

"The second general approach is what can we do in the winery in terms of adapting to changing the juice composition that we may start to see."

This research comes as climate studies show a gradual warming in Canada over the past 40 years.

"Winters are getting warmer," says Brock climatologist Tony Shaw. "We're not seeing as many days with sub-zero temperatures that are harmful to viticulture."

That change is important because the No. 1 factor limiting where grapes can grow in Canada is extreme winter temperatures.

 The changes may also bode well for some red varieties such as cabernet sauvignon, which prefers a long, warm growing season.

On the other hand, pinot noir lovers (like Miles in the movie Sideways) could be out of luck.

"For varieties such as pinot noir, which is a typical cool climate variety, that variety might be under some threat if the temperatures continue to warm because pinot noir prefers fairly cool growing conditions, especially as it reaches maturity in the month of September," Shaw says.

Shifting icewine

Then there is icewine, the sweet, expensive and exclusive vintage that put Niagara on the map and has a special weather requirement all its own: temperatures must fall to at least –8 C before picking the frozen grapes off the vine can begin.

"It's been our entry onto the world stage for a number of years now," says Pickering.

Opportunities to pick grapes for icewine production have been decreasing in Niagara. (Dave Chidley/Canadian Press)

"It's something that everyone's concerned about because you need a consistent window during winter of temperatures that are between –8 and –11 degrees. And what we've found this year, and I guess if you look historically over the last few years, the number of windows in which we get those temperatures are actually decreasing."

But if icewine became less viable in Niagara, where the winters are getting milder, perhaps its production could move a little further north, where there might still be enough cold weather.

"If the icewine industry is suffering in Niagara, there's a good chance it can shift a little bit northwards and that's where Grey County might be advantageous," says Shaw.

Research at Brock, which received $2.86 million in funding from the Ontario government last year, has included efforts to improve monitoring of climate conditions in vineyards so that growers can know when it's best to turn on their wind machines (and so reduce the risk of frost), or prune their vines.

The research is also looking at ways to boost sparkling wine production, something that is still in its early stages in Ontario.

"Sparkling wine grapes don't need to reach the same level of ripeness as you do for table wine," says Pickering. "If you have a season that's interrupted for instance with lots of rain or a shortened growing season, those grapes might be good for sparkling wine."

Extreme weather

Other research is looking into developing an appassimento style of wine, where the grapes are dried off the vine, similar to Amarone, a rich, dry Italian red wine.

British Columbia is also experiencing milder winters, according to the climate data, and that could have implications on where grapes are grown.

Research by Denise Neilsen and others at the Pacific Agri-Food Research Centre in Summerland shows that both minimum and maximum winter temperatures have increased a few degrees over the past century, notably in the Okanagan region, which has allowed for the development of a European wine-grape industry since the late 1970s and early 1980s.

"In general, if we look into the future we would expect that these temperatures would increase in the winter and that would affect most of British Columbia," Neilsen says. That would enable grape growers to shift some of their more tender crops to higher latitudes or more northerly locales. 

Other research is showing that colder temperatures are popping up more often in the later part of the year, rather than in January or February, which can be problematic for viticulture.

In the fall, grape vines are not yet acclimatized to their maximum seasonal hardiness, so the potential rises for more damage to vines.

"We are seeing this increase in risk just in the late part of the fall and the early winter that it is somewhat unexpected, so how that's going to play out into the future we don't know," says Nielsen. "It's all part of the idea that we have extreme events."

Watch and react

While B.C. wineries have been concentrated in the Okanagan, production has expanded into other areas.

"The BC Wine Institute sees new plantings each year from our membership," says BC Wine Institute executive director Miles Prodan. "Climate change will alter B.C.'s viticulture landscape, but it also opens the door for new potential planting sites."

Winemaker Bill Pierson of Lillooet, B.C., has one question about the climate and seasonal temperatures: 'What is average anymore?' (Courtesy Fort Berens Winery)

At the Fort Berens Winery in Lillooet, in the south-central Fraser Valley, the decision to establish the business in 2009 was based on a careful review of climate data from 1945 to 2000.

"We saw a climate that is very similar to south Okanagan, which is very suitable for growing grapes," says owner Rolf de Bruin.

De Bruin and winemaker Bill Pierson are cautious about equating any weather trends they've noted with climate change, and in fact say winters have tended to be a bit cooler recently.

"My question," Pierson says, "is what is average anymore?"

There's no easy answer to that, though, so Pierson falls back on the longstanding way all winemakers try to ply their craft: watch the weather as closely as you can, and react as quickly as you can to get the best vintage possible.

It is a view shared by Niagara winemaker Emma Garner at Thirty Bench Wine Makers near Beamsville, Ont., who welcomes whatever conditions Mother Nature may throw her way.

"It's all part of the fun. You never know."