Wine and Temperature

For the past few years, so called “big, cocktail-style wines” have been the rage among the hoity-toity wine crowd. But things might be changing willy nilly, especially when it comes to California wines. Which means goodbye and good riddance to overpowering Cabernets boasting alcohol levels of 16% and hello to acidity and symmetry.

The reason for the change is California’s mild summer weather. Northern California, where all those exquisite vines are located – places like Napa and Sonoma – is experiencing dampness, cool morning fog, and afternoon temperatures 10 to 20 degrees below normal for this time of year. A few growers have been overheard wondering aloud if the strange weather pattern is somehow connected to global warming. What they’re really saying is that the cooler weather is inconvenient. It has advantages and disadvantages for the vines.

Here’s the deal as far as disadvantages are concerned:

Cooler temperatures delay the harvest by two or three weeks because the vines take longer to fully develop, so if the fall rains arrive a little early, the growers could be left out in the rain – literally. Adjacent to the risk of rain is the threat of disease posed by the inordinate fog and moisture. Growers prevent disease by spraying sulfur to restrain mildew, and by making sure canopies let in enough sunlight and air, which hinders wetness settling into the grape clusters. If that’s not enough to worry about, grapes such as petit sirah, cabernet sauvignon, and zinfandel ripen late. They need the sun’s warmth to coalesce their elements into nobler forms.

Growers ensure their late ripening grapes attain proper maturity by thinning the grape clusters. They remove the unripe fruit. This removal process allows the leaves on the vines to distribute more sugar to the remaining grapes. Cool weather calls for more thinning than normal, which affects grape yields. Low yields affect profits and, since many growers have already reduced their prices by up to 25 percent because of the current economic crisis, lower yields are not very attractive.

Those are the primary disadvantages connected to the unusually cool weather in California. Now let’s take a gander at the advantages:

Early ripening grapes – chardonnay and pinot noir – love the cooler temperatures, which causes them to flourish. Growers have to adjust their harvest schedules by a few weeks, but they don’t mind. In fact, growers in Santa Cruz are eager to see just what kind of vintage they will get. They think it could be “the bomb.” Balance and complex flavor are expected, and that translates into outstanding, subtle wines, which is precisely the type of personality a superb chardonnay should display.

Even for the late ripening grapes there is an upside. Cooler weather translates into slower maturation of grapes on the vines. Slower maturation translates into lower sugar levels and lower alcohol levels. This means the harvest has great potential, if one prefers wines with a rich, resonant voice, under lilting control, rather than the exaggerated absurdity of brassy cocktail wines.

In other words, this season’s harvest could turn out to be a great vintage. The flavors could be velvety and less vehement, producing a vintage akin to that of 2005, also characterized by cool summer weather.