[...] the study warns that the upswing in quality may not last forever, and a hotter planet looks like bad news for French vineyards in the long run. In California, meanwhile, the relationship between climate change and wine quality is not nearly as straightforward as what the study authors observe in France. “When people talk about climate change, they talk about it as this theoretical thing that’s going to happen in the future,” says author Benjamin I. Cook, of NASA’s Goddard Institute for Space Studies. Published last week in the journal Nature Climate Change, the paper, which Cook co-authored with Elizabeth M. Wolkovich of Harvard University, tracked climate data and grape harvest dates from wine regions in France and Switzerland for over 400 years, from 1600 to 2007. The authors then looked at wine quality — an admittedly subjective measurement, here based on English critic Michael Broadbent’s tastings of French wines from the vintages 1900 through 2001. [...] Cook and Wolkovich found that since 1980, drought has not been a reliable predictor of harvest timing, as it had been for the hundreds of years preceding it. “Here in California, temperature alone is the driver of harvest timing, but early harvests are not necessarily correlated with high wine quality,” says Carole Meredith, professor emerita of viticulture and enology at UC Davis and the proprietor of Napa’s Lagier Meredith winery. [...] a very early harvest in California may be the consequence of a late summer heat wave, which can diminish fruit quality. Proximity to the Pacific Ocean will be an important factor here, because even with some increase in ocean water temperature, the waters off the Northern California coast will still have a moderating effect on temperatures in coastal regions. In England — generally thought of as chilly and wet — a burgeoning sparkling-wine industry has taken root, made possible by the fact that the growing season average temperature has held above the cool-climate viticultural minimum of 13 degrees Celsius since 1993. “Frankly, from my point of view, I hope it never gets normal,” says Smith. Because that is the joy of wine.
