Is the end near for pinot noir in Carneros?

Dozens of people crowded into a meeting Tuesday to discuss the possible effects of climate change on Napa Valley’s grape growing industry.

Featured speaker Kim Nicholas Cahill at the Napa Sustainable Winegrowing Group event suggested that if Carneros is no longer cooled by the bay breezes and marine layer as it is today, change may be in order in the vineyards.

Cahill is a viticulture associate at UC Davis whose family includes Sonoma county farmers. She has a Ph.D. from Stanford University and has extensively studied local effects of climate change.

She said she was “not aware of anyone in Carneros switching right now from pinot noir on a large scale. But it is something people are considering.”

At least 60 people crowded into a small conference room at Walsh Vineyards Management to get an update on local climate change impacts on the Napa Valley.

Nicholas Cahill told the audience that predictions are for a nearly 1 degree Fahrenheit increase in temperature by 2020. “We can expect to live in a climate we have never lived before,” she said.

Under that scenario, the best location for pinot noir is likely farther north, along the coast of Oregon and Washington.

Will it really happen? “I hesitate to say exactly what people will do, because it is easy to over simplify the issue. Growers might have some very innovative options they may take advantage of,” said Nicholas Cahill after the meeting.

For example, more cutting-edge growers may experiment with different trellising systems to provide more shade. “There’s a laundry list of possible things ... different irrigation techniques ... but to say how much benefit, that has not been completed,” Nicholas Cahill said.

Warmer temperatures will stress vines more than current conditions, she said.

Exactly how much warmer temperatures will get depends on greenhouse gas emissions humans continue putting into the atmosphere during the next 20 to 30 years, added Nicholas Cahill.

“The point is vine development is tied to temperature,” she said. The goal is to have a certain balance between tannins and acids at harvest time. With warmer temperatures, sugar levels also tend to go higher while acid levels drop. That is not desirable with pinot noir.

Nicholas Cahill said research reveals that the Napa and Sonoma valleys have seen more of an increase in night-time temperatures than daytime.

“The wine industry must overcome barriers and adapt to these changes. It will require an integration of researchers and growers in a balanced dialogue,” she said.

One person in the audience told Nicholas Cahill that he has heard that growers of gewurztraminer in Austria are switching to warmer weather varietals due to the early signs of climate change. He added that cooler varietals seem to be moving toward France, which is experiencing cooler weather patterns.

Another person in the crowd suggested local grapegrowers should begin talking with growers in Paso Robles, which is warmer than the Napa Valley. “They have that experience.”