By 2040 Northern California might have 50% less land suitable for growing premium wine grapes due to climate change. According to a new study by Stanford University, increased temperature can significantly alter the viability of certain grapes in Napa Valley. But, on the flip side, cooler parts of Oregon and Washington will become better wine-growing regions.
The study's coauthor, Noah Diffenbaugh, estimates that in 30 years the average global temperature could be 1.8 degrees higher than today (using standards from the Copenhagen Accord).
Pinot Noir and Cabernet Sauvignon grow around 68 degrees; if temperatures increase by two degrees, the varietals will likely not grow as well. To adjust to a warmer planet, Diffenbaugh suggests that Napa vitners plant more heat-tolerant grapes or use an irrigation or trellis system to keep the vines cool.