Climate change = coastal cooling
I blogged a year ago that I don’t think coastal California is warming up. “It’s almost official — coastal California is getting colder, not hotter,” I wrote.
Well, now it is official.
Last week, the San Francisco Chronicle reported that scientists have concluded that “Global warming is warming the interior part of California, but it leads to a reverse reaction of more fog along the coast.” And fog, as we all know, is what makes the California coast cool during the summer months.
The article continues: “…colder summers are indeed in store for parts of the Bay Area.” And with the Pacific waters even colder than usual, the coast is in the midst of a chill-down of unknown length. The California Current brings polar water southward, past Washington and Oregon and off our coast, which is why swimming in the Pacific in Northern California is not advisable without a wet suit, even in high summer.
Just where the boundary line is between “interior” and “coast” is elusive. Sacramento is definitely interior. So is Livermore. Is Napa Valley interior? I don’t think so, especially the southern parts, which are more open to the maritime influence than Livermore. Even Calistoga gets some fog and maritime influence, which comes in from the Russian River Valley through a gap in the Mayacamas. (Bo Barrett, of Chateau Montelena, pointed that out to me.)
This past May was the foggiest in 50 years in and around the Bay Area. And June, as everyone knows who lives here, was a real chiller. Yes, we had mini-heat waves in both months, but by the end of June, everyone was talking about how cool it’s been. Even when the sun was out, temperatures had a hard time busting out of the low 60s here in Oakland, and the mid-70s in wine country. For much of June, the weathermen were telling us temperatures were running 20 degrees below normal inland. My local TV weatherman said June was the coldest in more than 100 years.
Actually, the fact that the coast is cooling was reported nearly a year ago, in Scientific American magazine, which said that “A group of northern California scientists have found a new bend in the Gordian knot of global warming: coastal cooling…as temperatures rise in California, so do pressure differences that control cool Pacific winds. That means higher temperatures inland create lower ones at the coast.” One of the scientists made this interesting remark: “…the findings bode well for California’s wine regions…”.
I don’t know what exactly this means for coastal California’s wine regions, from Santa Barbara north to Anderson Valley. But it does seem like it’s not going to get as hot as people had feared. As for the Central Valley, if you think it’s hot there now, just wait. (Should be great for the grapes…)
By the way, as I write his on Sunday evening, the forecast is for a warming trend this week. Temperatures might hit 100 in the hotter inland valleys, including Napa-Sonoma. I realize the irony, in light of what I have written. But it doesn’t undermine the thesis: wine country is cooling off.