We’re having such a lovely summer this year in Napa Valley. Our days have been made up of comfortably warm daytime temperatures followed by chilly, foggy nights with the occasional brief blast of heat, so far, which happens to be the formula for an excellent Napa Valley vintage!Marty wrote in to ask about frequent references I make to warm vs. cool-climate wine and this is a great time of year to talk about it, although the real story can’t be written until harvest is over, hopefully by Halloween.
If you like to garden, you know how seasonal temperatures affect the ripening pattern of your fruit and vegetables. Imagine trying to ripen tomatoes on your patio if you live San Francisco, where it’s foggy daily, in the summertime, and temperatures rarely rise above 65F. Those are going to be some tart, green tomatoes, right? The same thing applies to grapes. They start out with high levels of acid, low levels of sugar, and vegetative flavors. As the weeks go by they gain fruitiness and sweetness, and the acid decreases, provided they get enough heat and sun. So, depending upon where they’re grown they’ll ripen slowly or quickly and end up tasting more or less ripe since the level of sugar and acidity is affected.
World wide, the best winegrowing regions tend to have Mediterranean climates and the growers in each region want the same thing: enough sun and heat to bring the grapes to complete ripeness, but not so much that the flavors don’t have time to mature or the grapes lose too much acidity along the way. And, each region has its challenges. As we go from cooler to warmer conditions the flavors evolve, accordingly, from vegetal/herbaceous/earthy to fruity, ripe and even tropical or dried-fruit flavors.
Napa Valley is considered a warm-climate region, the last two vintages not withstanding. Of course, Cabernet Sauvignon is king here. Bordeaux is the most famous cool-climate counterpart for Cabernet.
Warm-climate wines are generally relatively low in acid and high in alcohol. The sugars accumulate very easily during the long, warm growing season. The acid softens and this region is famous for its full, ripe, fruity flavors. The downside to a warm climate is that on the hotter vintages the grapes may lose too much of the refreshing acidity and the sugars may accumulate faster than the flavors mature. On the warmest years, fruitiness may evolve into dried fruit, raisin-like or pruney character. A solid alcohol gives wine much of its body, but too much isn’t a plus, if it can be tasted or feels too hot on your palate. It also gives an impression of sweetness. Lack of acidity can take away from overall balance and aging potential. It’s quite common for winemakers to add acid to the juice. Also common, but almost never discussed is the addition of water at crush time to dilute the sugar and, therefore, lower the alcohol. Cool-climate wine
These wines tend to be relatively high in acid and low in alcohol. Most of the famous European regions are considered cool-climate wines. The winemakers pray for a warm, dry summer and fall in order for the grapes to become fully mature. In some years, sugar must be added to boost the alcohol and give the wine a bigger, more satisfying mouth feel. The flavors are often less fruit forward, showing more herbaceous, earthy and mineral character, along with the fruit. The wines from lesser vintages may be thin and sharp. Overall, these wines may not be as approachable as warm-climate wines, in their youth, but the acidity helps to keep them lively and allows their flavors to unfold over the years so they’re enjoyable later on.
The last two vintages in Napa Valley have resembled Bordeaux on a not-great year: We had unseasonably cool weather and rain at harvest time. So, we’re pleased as punch with the 2012 vintage so far. We’re all hoping Mother Nature continues her good mood in regard to northern California right through crush. Lord knows, she hasn’t been so kind to the rest of the country! I like my whites quite tart, so I lean toward cool climates when I make my selection. I like everything, but tend to prefer the ripe flavors of warm-climate reds so, in that case, I often shop for Napa Valley and other California warm spots. Which way do you lean? Do you prefer rich, ripe flavors or a leaner style with a good zing of acidity? Send me your wine question For a free email subscription go to home page, right column