“Dr. Vino” Tyler Colman claims to have calculated the carbon footprint of wine and come up with a simple answer: If you live west of the line he’s drawn through the middle of the country, you should buy wine from California, and if you live east of the line, you’re better off buying from East Coast or European wineries. You may have good reason to think twice about his findings, however.
Colman and his partner Pablo Paster use their research paper to unload a metric ton of scientific-sounding chatter, largely regarding variables and calculations that are either undeniable or not on the table, and then use this data to somehow carve out their precise line. Easily digestible, easily reprintable. Colman and Paster’s proscriptions about wine buying have run, seemingly unquestioned, in several places, including a New York Times op-ed and in a non-peer-reviewed section of Science (subscription required).
But their research is suspect. First, they look at just three wineries located in three widely disparate growing regions, Yellow Tail (New South Wales, Australia), Coulee de Serrant (Loire, France), and a hypothetical “cult” winery in California’s Napa Valley. These three wineries ship wine to just one major market, Chicago. (Colman, when he’s not professing at New York University, happens to teach at the University of Chicago.)
Large cargo ships are said to carry the bottles from the Australian and European wineries. These ships dock in the U.S. (Los Angeles for Yellow Tail; New Jersey for Coulee de Serrant) and the wine is then hauled by road or rail to its Chicago destination. By comparison, the imaginary Napa winery (call it L’Strawman) ships exclusively by air overnight express.
Basically, Colman and Paster use lots of fancy footwork (and irrelevant calculations) to say that shipping a bottle of wine via sea and land is more efficient than flying the same bottle in a plane, even for a shorter distance, if you divide the carbon output by the number of bottles each vessel can carry. But they are comparing apples to oranges and vastly oversimplifying the issue. If they compared apples to apples—mass market to mass market (or cult wine to cult wine), normal carriers to normal carriers—it is unlikely that Colman and Paster would get a simple line dividing the country. Or, for that matter, very much attention.
(Thanks to David Egerton, Ph.D. candidate, University of Louisville.)