One week after a scorching heat wave set all-time temperature records across southern France in July, Beniôt De Sutter, master distiller for Courvosier, hosted an al fresco lunch for a handful of journalists in the vineyard of one of the cognac maker’s wine growers, Michelle Guilloteau. On a farm, cross-table conversation inevitably turns to the weather at some point, and as we discussed the recent stretch of heat, De Sutter gestured across the table to Guilloteau.
“Michelle started in the 1960s as a wine grower, and he has never seen this phenomena,” De Sutter says. From across the table, Guilloteau nodded in agreement. Though the previous week’s heat had subsided, it remained unseasonably warm in Cognac—even for July. Longer, hotter summers have in recent years forced growers to harvest their grapes earlier than in past decades, but the heat presents just one of an increasingly unpredictable range of threats to Cognac’s vast tracts of Ugni Blanc vineyards. Growers have long dealt with a late frost in April that threatens their budding grapevines, followed by the occasional hailstorm in May, June, and July—but always in that order.
“This year for the first time ever we had hail before frost,” De Sutter said. “We had hail in April that hit 2,000 acres of vines, and then we had frost in early May, ten days after the hail. It’s crazy.”
Wine regions around the globe are racing to adapt to shifting weather patterns and longer, hotter summers as global temperatures rise. Some wines from cooler regions—like Germany’s Rieslings or Cabernet Francs from France’s Loire Valley—have benefitted, experiencing bumper crops from longer, warmer growing seasons. Elsewhere, growers and producers have begun taking unprecedented steps to mitigate the deleterious effects of what increasingly looks like a new normal. French winemakers haven’t experienced sustained heat and dry harvests like the ones they’re currently experiencing since the 16th century.
But it’s difficult to think of a region more susceptible to sustained changes in climate than Cognac, boxed in as it is by strict regulations, a requirement for consistency, and an overwhelming reliance on one singular grape varietal: Ugni Blanc. One extremely hot stretch of summer could ruin an entire vintage and put a serious dent in an industry whose retail sales grew 40 percent between 2013 and 2018, topping $5 billion according to figures from Euromonitor International. That potential has the entire Cognac region collaborating in search of ways to mitigate the risks, some of which may require it to change or abandon viticultural traditions reaching back centuries.
Cognac is made by distilling a low-alcohol base wine made from Ugni Blanc into a high-alcohol grape spirit known as “eau de vie,” which is then aged in French oak barrels and blended by each producer into its own signature house cognac. Consistency is key; the quality of the product is so sacred to the region’s producers that over time they’ve crafted an extensive set of regulations governing its production. Not least of these regulations is geographic. Cognac and its ingredients must be produced in the Cognac region, meaning producers can’t relocate their operations or source their grapes from cooler regions and still label the resulting brandy as “cognac.”
Cognac’s regulations also restrict practices like the use of irrigation in fields or preservatives in the base wine, limiting the tools growers have to cope with drought and extreme summer heat. And while winemakers can roll with the seasonal punches climate change throws at them by playing up variations between vintages as unique expressions of each year’s growing season, cognac houses have no such luxury. Variations from one bottle to the next are viewed as flaws rather than desirable nuances, placing increased pressure on producers to somehow manage growing conditions to obtain an eau de vie with the right characteristics.
“We need acidity and we need weather that’s not too hot,” says Patrice Pinet, Courvoisier’s master blender and president, who also heads the Syndicat des Maisons de Cognac, an industry body that coordinates between the region’s cognac producers. That high-acidity in the base wine is critical to making good cognac, and it’s why Ugni Blanc—a grape varietal uniquely suited to distillation—is planted almost exclusively across Cognac’s rolling hillsides.
But Ugni Blanc’s prized acidity declines in extreme heat, and longer summers only exacerbate the problem. In recent years growers have mitigated the issue by harvesting earlier, but further rises in average temperature would leave the industry in a precarious position. “Thirty years ago we were harvesting the grapes in the beginning of October,” Pinet says. “Now we are collecting the grapes mid-September. If it continues to go like this, and we have to advance [the harvest] by another three weeks in 30 years, we have to be prepared for these conditions.”
Though competitive in the marketplace, the region’s big producers like Hennessy, Martell, Rémy Martin, Rémy Cointreau, and Courvosier (owned by LVMH, Pernod Ricard, Rémy Cointreau, and Beam Suntory, respectively) are remarkably cooperative when it comes to shared technical challenges. In collaboration with BNIC, another cognac trade group, Martell has devoted a section of its greenhouse space and vineyards to experimental grape varietals, some of which are new hybrid grapes that Martell and BNIC hope will not only boost the region’s efforts at sustainable viticulture, but also stand up better to warmer conditions while maintaining high acidity. Courvoisier has likewise dedicated part of its own vineyards to experimentation. Most research is funded jointly—predominantly by the larger producers—and results are shared openly within the industry.
Varietals like Monbadon—a grape long considered uninteresting to winemakers due to its low sugar and high acidity—are getting a second look in a warming world, Pinet says. If grapes have to be collected earlier and earlier, Monbadon’s potential to produce a high acid, low alcohol wine could prove ideal, provided it can produce an eau de vie that meets the region’s high threshold for quality. Courvoisier produced its first eau de vie from the grape this year, though it will take at least three years in the barrel (and probably more) before the company will know if it’s a viable candidate for a quality cognac.
“We are able to move things along as long as we are able to ensure quality,” says Martell Vice President Pierre Joncourt. “Everyone is aligned, but you can’t do it quickly.”
If temperatures continue trending upward that long-term research could prove prescient—though it may not be enough, says Spiros Malandrakis, an alcoholic beverage industry analyst at Euromonitor.
“Medium- and long-term, there is no doubt that these issues will try to be mitigated through alternative grape varieties that are more resistant, or tech that will to a degree protect this specific area for cognac,” Malandrakis says. But faced with more than a couple of degrees of average temperature increase, parts of Europe could become unsuitable for cultivation or water resources might become scarce, a scenario in which the quality of cognac will be the least of the world’s problems.
“It has less to do with the grapes in cognac and more with the massive levels of societal disruption that climate change could bring,” Malandrakis says. “Super premium products do not particularly do well in post-apocalyptic environments.”
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