The wine industry may be among the very few in which a leading figure will smile broadly when asked about climate change and declare, spontaneously, “I love it.” The comment came this week from Egon Müller, owner of the famed Scharzhof estate in Germany’s Saar Valley, when I asked him about the trend at the Riesling Rendezvous in Bellevue, Washington. The reason for his elation, of course, is that cooler-climate regions like the Saar often struggle to achieve ripeness, and warmer temperatures are certainly helping. But what happens when it eventually gets too warm?
Two climate scientists at the conference, Dr. Greg Jones of Southern Oregon University and Professor Hans Schultz of the University of Applied Sciences Wiesbaden/Geisenheim, noted that as temperatures have risen in recent decades (and continue to rise) grape ripening and harvesting have taken place earlier, among other things. “I have looked at wine regions all over the world,” Jones said, “and I can tell you I don’t see any of them getting colder.” He said this has resulted in longer growing seasons, warmer dormant periods, reduced frost damage (although when frost does occur it is causing greater damage to vines), and earlier phenology (plant growth events). “The plant is telling us it’s living in a different environment, “ he said. Schultz noted that sugar levels in grapes are getting higher and acid levels are decreasing, which doesn’t bode well for balanced wines.
The bigger impact, they said, will come when temperatures exceed the optimum range for growing various grape varieties. Over time, wine growing regions will shift north toward cooler climates in the Northern Hemisphere and further south in Southern Hemisphere. Jones wondered whether, over the next 40 years of so, the Napa Valley would become a region for table grapes and Germany’s Rhine Valley would become more suitable for syrah than riesling. He had much more to say when I interviewed him about warming trends and wine in the video above.