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Brock University viticulturist Jim Willwerth measures leaf stress in a Niagara, Ontario, vineyard.

Ontario's wine makers are fighting to protect their grapes against Mother Nature's wrath.

The destructive forces of climate change are already being felt in the world's biggest wine-producing regions - California, Europe and Australia - as the steady rise in global temperatures scorches vineyards and depletes water supplies.

As a heat wave grips Ontario, grape growers in the province face their own set of challenges as warmer temperatures radically change the dynamics of their industry. Hotter summers can cause heat stress for grapes, which can threaten signature Ontario whites such as chardonnay and riesling.

Although ideal growing conditions vary depending on the variety, grapes must be grown within specific temperature and precipitation ranges. White grapes tend to thrive in cooler conditions but excessive heat can also hurt the quality of Ontario reds such as pinot noir.

Warmer temperatures are also being blamed for the proliferation of foreign pests in Ontario vineyards, which is pushing up costs for grape growers.

Kevin Watson estimates his company, K.J. Watson Farms Ltd. in Niagara-on-the-Lake, is spending four times more on pest management than it did five years ago. He uses a variety of techniques including traps, mating disruption and sprays.

"We're doing as much as we can to control as much as we can. But you know, at the end of the day, Mother Nature, she is what she is," he said.

While some insects can damage the fruit or leaves, others such as the multicoloured Asian lady beetle can also taint the taste of wine if processed along with the fruit. That's because the beetle excretes a stinky, yellowish fluid that contains a chemical called methoxypyrazine, which can spoil the flavour of wine.

Nevertheless, climate change is proving to be a mixed blessing for Ontario's industry, which in 2009 accounted for $575-million in wine sales. Experts predict that climate change will not only allow the industry to grow grapes in new parts of the province, but the longer growing season could also be a boon to red wine production - long considered Ontario's weak spot.

"I don't want to sound ruthless here, but it is competition, right?" said Debbie Zimmerman, chief executive officer of the Grape Growers of Ontario. "Anywhere we can replace a bottle of [imported]wine on the shelf at the [Liquor Control Board of Ontario]... that's our goal."

Earlier this month, Ontario announced it is giving $2.86-million to a team of scientists studying the impact of climate change on the grape and wine industry. The project, which is being spearheaded by researchers at Brock University's Cool Climate Viticulture and Oenology Institute, will include research on grapevine hardiness during winter, weather modelling, and developing new winemaking techniques.

Winemakers say innovation is the key to keeping their own costs in check, while better competing with foreign rivals at the liquor store. Hot weather is already impacting key winemaking regions in Western Europe including Bordeaux and Champagne in France in addition to Germany, Spain and Italy.

A recent study by Stanford University predicted that global warming could reduce northern California's premium grape-growing territory by 50 per cent within 30 years - if average global temperatures were to increase by two degrees Fahrenheit over that period.

"It is quite likely that in years to come you could see some major issues with grape production in these areas," said Tony Shaw, a Brock professor of geography and CCOVI fellow. Hotter weather in those areas can hurt grape quality by driving up the sugar and alcohol content, which hurts the aroma of premium wines.

Higher temperatures could have an impact on the types of grapes grown in various parts of the province, while also reducing the total number of picking days for grapes used in ice wine, Mr. Shaw said. Climate change might also open new areas of Ontario to wine production, he said, including Simcoe, Huron and Norfolk counties.

Strategic expansion is key because the Ontario industry, given its smaller size, higher labour costs and unfavourable climate, is unable to compete against imports on price alone. "Ontarians are patriotic up to $10. Beyond that Fuzion wine from Argentina - it looks good," he said.

Craig McDonald, senior winemaker at Andrew Peller Ltd., based at Hillebrand Winery in Niagara-on-the-Lake, said climate change is also creating new opportunities for vintners particularly with red wines such as merlot, cabernet franc and cabernet sauvignon "It has always been the Achilles' heel of Ontario: We make great whites but our reds are more inconsistent," he said. "We've still got more to gain by warming up."




The wine industry in B.C. has seen steady growth, with sales more than doubling to $182-million in the last decade, and the number of growers increasing more than five times. Warmer winters in the region could mean less risk of frost damage in some places, but balmy climates are also more welcoming for pests that attack grapevines, such as bugs that spread Pierce's Disease.


Ontario wines hold a 45-per-cent market share of all wines sold in the province and drew $575-million in sales in 2009. But as the climate changes, as in B.C., the Niagara industry could be threatened by pests that are normally killed off by cold winter temperatures. The average growing season temperature could increase by as much as two degrees Celsius, from the current April-to-October average of 15C for the Niagara region.


For the world's second-largest wine producer, anything that puts winemaking in jeopardy is a crisis of heritage. European temperatures are on the rise, as are UV rates that affect grapes. In Bordeaux, warming trends caused the harvest to move two weeks earlier in the last half of the 20th Century. In the century's final 20 years, UV radiation in Central and Western Europe rose 11 to 13 per cent. As the mercury rises, it could be more difficult to produce France's fabled and highly protected Champagnes, as well as other famous names such as the red wines of Châteauneuf du Pape, at their former levels of quality.


High temperatures aren't the only cause of concern for California vintners; the state is drying up, climate projections signal more drought to come, and the more than 2,000 wineries need plenty of water to irrigate their crops. The state's economy relies on the $51.8-billion (per year) industry for tourism, trade revenue, and hundreds of thousands of jobs, both in-state and elsewhere in the U.S.


Australia's wine industry has built its brand in recent years, and is now the fourth-largest exporter in the world, with exports worth $3.02-billion Australian ($3.09-billion) as of 2007. The question is whether it can hold on to its reputation as conditions change. The country's grape-growing regions are expected to see a boost in their annual average temperatures by as much as 2.6C by 2050, leading to earlier harvests and warmer harvest days.


Wine growers in South America are heading for the hills. Vintners in Chile and Argentina are moving higher into the Andes where temperatures are cooler. Argentina has seen its glaciers shrink and less snowfall, meaning wine producers depending on water from Andean rivers could be under pressure, especially during droughts when glaciers keep the water flowing.

Susan Krashinsky