I’m going to spend a lot of time in this post tearing down Vintage Charts. So why don’t I begin with a few supportive remarks about the general concept. Clearly, most wines are different from year to year. At least wines are that haven’t been blended for consistency. Wines from marginal growing areas, say northern Europe, are often dramatically different from year to year.  In fact, vintage years can often be better indicators of quality than who produced the wine when considering top vineyard properties from northern Europe. Moreover, high-acid wines from northern Europe, which age very well, allow time for a consensus about vintage quality to emerge through repeated tastings.

Evaluating California vintages with any degree of accuracy is another matter. First,California is a very big area. It’s very hard to reconcile rain in Napa on 25 Sept after all the Chardonnay has been picked, with the same storm in Monterey before the Chardonnay harvest even begins. Similarly a great year in Californiafor Pinot Noir may not be a very good year for Zinfandel. In Germany or Bordeaux a Vintage Chart basically evaluates a single varietal, which is picked over a 15 to 20 day period. A California Vintage Chart pretends to evaluate eight varietals picked over two months. Can’t be done. Even if CA does have more consistent growing season weather than northern Europe.

Fog Entering Bien Nacido Vyd, Santa Barbara

Vintage scores where 9 out of 10 years are either ‘good’ or ‘great’ are generally offered by promotional Trade organizations, or somebody else with an inventory to sell. They are useless. The following Chart shows a strong alternative technique. In this Chart each decade must be divided into ten levels (“forced ranking”). Some year has to come in last. Naturally, reasonable people may disagree. May? Reasonable people will disagree. That’s the nature of fine wine, and of fine wine conversation.

But there is a bigger question to be explored here: Must Vintage Charts always be subjective, or are there objective measurements which could be employed to predict the quality of wines from any particular growing season? A good example is crop size. Traditional wisdom holds that smaller crops yield more depth and concentration. Hence the technique of “green harvest,” wherein clusters are thinned following veraison (color change). Personally I do think crop size can indicate strong years. Side-by-side tasting of the same Napa Cabernets from 1990 and 1991 is an excellent illustration. Many CA Vintage Charts list 1991 as the superior year. No way. The crop in 1990 was cut by a late frost. Side-by-side I always feel the 1991 seems to have had 3 oz. of water poured in each bottle. I also feel 1999 ~ lowest yield of the last two decades ~ was a spectacular, very reliable, and somewhat overlooked vintage.

Unfortunately these illustrations do not tell the complete story. There are also several examples of the vintners’ nirvana ~ very large crops in years widely viewed as exceptionally good quality. 1997 and 2005 would be particularly strong evidence. I’ve always considered 1997 way too robust stylistically for my personal palate, but there is no arguing about its success in the marketplace. On the subject of the 2005 vintage ~ biggest yield of the decade ~ even I am on the bandwagon. No less an authority than Dr. Richard Smart, perhaps the world’s pre-eminent viticulturalist, says, “Great wines occur when healthy vines get fully ripe.” That is precisely what happened in both 1997 and 2005.

Overall Harvest Size in California  [Wine Institute]

Which brings us to reports on vintage quality offered in San Francisco newspapers and on TV in early December each year. In 1995 I went to Australia, then in 1996 to South Africa, to work the crush at Coldstream Hills in the Yarra Valley then at L’Avenir Winery in Stellenbosch. Both trips were extraordinary experiences, both socially and physically. I went as a stagiaire, which is often translated as an intern, but in the wine industry should translate as well-educated, grunt labor. I was no spring chicken at the time, but I wanted to see the inner workings of a winery up close and personal throughout the chaos of a crush. I already knew what I would see as a journalist visiting a winery during the crush. In Australia and South Africa, I wanted to learn what journalists do not see during a crush.

I learned winemakers have to make hundreds of decisions by the seat of their pants. When I interview a winemaker as a journalist, I frequently ask how a wine was made. This is often two or three years after the fact. Winemakers routinely tell me how they planned to make the wine. It’s not that they’re lying to me; they just don’t remember all the small things that go wrong. When actually on the scene, I found the gap between plan and execution is actually a chasm. Grapes don’t ripen on schedule. Pickers are not always available exactly when you want them. Same with equipment. Things break. Quantities are frequently not as one expected.

Which leads to an interesting phenomenon. Winemakers like to talk about tough vintages! They don’t do this with consumers, and they only do it with writers once they come to trust the journalists’ scientific curiosity. But it makes sense. Winemakers have every reason to be proud of the magic they perform in difficult years. Doesn’t mean the overall, industry-wide quality of wines from that year is likely to be noteworthy.

On a different, but often entangled track, it would be hard for any winery owner to be entirely objective about vintage quality either. When asked which of your daughters is most attractive, wouldn’t the logical response be to point out the charms of your unmarried female child? Best vintage? “Why, coincidentally it’s the one I currently have for sale.” Doesn’t surprise me one bit when winery owners extol the virtues of a vintage which featured a really big crop. They’ve got a lot of that one to sell. A short crop may imply concentrated flavors, but it’s going to sell out quickly, especially if it is really good quality. So why waste media exposure on it when you could be hawking the vintage of which you’ve got warehouse(s) full?

SST ~ Seasonal Surface Temperatures (ºC) in the Equatorial Pacific Ocean [NOAA]

Each figure is a three-month average. Hence ‘NDJ’ means Nov – Dec – Jan.

What is an ideal vintage in CA? That’s another quandary. Weather stations can provide objective data as to temperatures and rainfall. A Princeton Economics professor named Orley Ashenfelter has made a very strong case that he can predict auction prices on Bordeauxwines based on climatological data [http://www.liquidasset.com/feature1.html]. Hasn’t exactly been embraced by the industry, but his correlation does appear to work for Bordeaux. The problem in California is standards keep changing. A warm growing season, and hot – dry harvest (the features Dr. Ashenfelter looks for in Bordeaux), may produce fruity, forward, opulent Napa Valley Cabernets which sell briskly when they first come out (cf: the 2001 vintage). But do those CA wines have any cachet past their tenth birthday? 1974 was that type of year in Napa. The 1974 Napa Cabs mopped the floor with the harder, less ripe 1973’s when both were in the marketplace. Today most 1974 Napa Cabs smell like prunes, while many 1973’s are still in good shape. Collectors of California Cabernets need to think about when they will be consuming those wines in order to evaluate vintages. Long life for Napa Cabs probably does not derive from extreme ripeness.Each figure is a three-month average. Hence ‘NDJ’ means Nov – Dec – Jan.

Flooded Sonoma Vineyard

Drought years are another consideration inCalifornia. Some water stress on vineyards can serve to concentrate wines. After a lot of stress, however, the vines simply shut down, making awkward, unbalanced wines. Is it possible to measure El Nino / La Nina conditions in thePacific Ocean, and thus predict drought-induced vintage quality in CA? Not easily. It’s not even easy to predict CA drought based on El Nino / La Nina conditions.

In the table above an extended period of temperatures above 0.70 indicate El Nino conditions, i.e. warming of the surface temperatures in the Pacific Ocean along the Equator, which often brings rain toCalifornia. The opposite condition, an extended period of temperatures below – 0.70 indicate La Nina, i.e. cooling of the surface temperatures in the Pacific Ocean along the Equator, which often means drought for California.

Annual Rainfall at Placerville, Sierra Foothills [1,870 ft elevation]

* Rainfall figures are from July, in the year of the vintage, thru June of the following year.

** Average rainfall inPlacervilleis 39.50 inches. Figure shown is over or under average.

Take a glance at 1976 / 1977. They were definitely severe drought years. [Note the rainfall figures in 1976 above run from July 1976 until June 1977.] See also 1982 / 1983 which were definitely rainy, flood years. In the first instance the Equatorial Pacific Surface Temperatures would have predicted the opposite. In the second instance the ocean temperatures were split ~ hardly a strong indicator.

At the end of the day California Vintage Charts are very complicated undertakings. They are open to many interpretations. They may work best for you in the same manner political speeches analyze current events, i.e. arrive at your conclusion first, then look to the Chart for whatever justifications it may offer you.