Such rises in temperature are not limited to California or France. In Canada’s Okanagan Valley, winemaker Dave Paterson at Tantalus Vineyards has stopped Icewine production, despite its popularity and significant profit margin.
“We are getting warmer,” says Paterson. “We’re seeing that Icewine temperatures are a lot later, and they aren’t lasting as long.”
Canadian law requires Icewine to be produced from grapes naturally frozen on the vine. Grapes must be picked while the temperature is minus-8° Celsius (17.6° Fahrenheit) or lower, then immediately pressed.
Tantalus winemakers noticed that the Riesling grapes on vines in January or February, that were used to make Icewine, are now one of the only food sources available for local wildlife. Rather than have their crop further diminished by hungry animals, Paterson now picks the grapes sooner and uses them for other purposes.
“By the time we get to legal temps, it’s not worth it,” says Paterson.
At Familia Torres in Spain, winemakers see similar volatility. The winery monitors temperature and vine maturation data over the last 50 years from different points in its vineyards. Its data shows that Torres harvests start an average of 10 days earlier than it did 20 years ago. Also, the region’s average temperature has increased 1.2º Celsius (34.16° Fahrenheit) over the last 50 years.
BLB Vignobles monitors temperature and precipitation to assess water conditions year over year in Combaillaux, just northwest of Montpellier in France. From 1955–74, the climate in that area “fit” the water needs of the local Carignan grapes. However, from 1995–2014, while water needs stayed the same, farmers had a serious water deficit.
“We understand climate change with just a glimpse at how the chart curve changes over the years,” says Morgane Le Breton of Vignobles. “Every year we face a new challenge.”
“If they don’t sweat properly, the vines will shut down under intense heat,” he says.
Despite scores of scientific measurements at his fingertips, which includes data Saturnalia collected from the weather station in nearby Parras, in central Mexico, Raventos Llopart found the best way to monitor the impact of solar radiation is a simple bucket of water.
Raventos Llopart and his team leave a bucket full of water in the vineyard and measure its evaporation over time. They use the results to best determine levels of irrigation.
It’s an analog instrument in a very sophisticated toolkit, and it demonstrates the need for a “human factor” in climate analysis.
Lucas Pope, vineyard manager at Halter Ranch Vineyard in Paso Robles, California, points to the handwritten notebooks many farmers have kept for centuries. They may be illegible to anyone except the author, but they record factors like rainfall and significant weather events.
“Being relatively new to farming and not having a family history to lean on and learn from, my snapshot of what is going on with the earth’s climate has been a roller coaster the past 15 years,” says Pope. “Warm years, dry years, cool springs, harsh winters, early and late frost have all hampered grape growers’ efforts to produce the best possible crop with what nature gives us.”
Still, Pope warns against data collection for its own sake.
“If there is no time to spend dissecting the information that is being thrown at you all the time, is it doing you any good?” he asks. “Growers are being asked to do more work with less labor and resources, so selecting what to monitor and the quality of the data are ever more important.”
For those on the front lines of climate change, a cutting-edge toolkit is only valuable if you know how to use it.