Wine lineSee that green line on the map? Study it closely, boozehounds. Those of you to the right of it can enjoy a nice French Bordeaux. Those to the left should be getting your Pinot from Napa.

So concludes Dr. Vino in his excellent — and topical! — study, “Red, White and ‘Green’: The Cost of Carbon in the Global Wine Trade.”

The paper is nicely readable in addition to being thorough. Few details go unconsidered. Dr. Vino cares about the CO2 produced from the breakdown of sugar during the fermentation process. He mulls the land-use implications of grape production. He knows his screw caps from his corks.

All of these factors (well, not the corks) feed into a model that allows the paper’s authors to compute the carbon content of different bottles of wine drunk in various points in the U.S. Some conclusions:

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  • Transportation mode is the most important consideration. Distance matters, but not as much as how the wine is shipped. Container ships are more fuel efficient than ground shipping, which in turn is more efficient than air freight. So express shipping your bottles from boutique wineries is about the worst thing you can do.
  • The shipping factor results in a “green line” running roughly from Ohio to Texas. East of this line, you’re better off getting your wine from Europe via container ship. West of this line, you’re better off getting your wine trucked from California. You may want to consider relocating to a city on the green line to preserve your options.
  • As though you needed any further encouragement over the holidays, bigger bottles are more carbon friendly than smaller bottles. Much of the ship weight of wine is the glass packaging. Bigger bottles yield a more efficient wine-to-bottle ratio. Boxed wines and Tetra-Paks are even better, at least from a carbon standpoint. Another good practice is shipping wine in bulk containers and bottling it close to the point of sale.
  • Climate change is a serious issue for the wine industry. This should come as no surprise. Wine is an agricultural product whose quality is exquisitely sensitive to local growing conditions. Some researchers have predicted an 80 percent decline in U.S. premium wine grape production in this century due to climate change. Drought-prone Australia, one of the largest wine exporters in the world, should also be nervous.
  • Organic farming isn’t much help. The authors are surprised by this, but they shouldn’t be. Despite its other environmental benefits, organic farming doesn’t help a lot on the climate change front. Transportation is still the overriding issue.

Ever the oenophile, Dr. Vino has some advice for those who don’t want to give up their New Zealand Sauvignon Blanc. His main recommendation is to “offset” your wine drinking by giving up other carbon-heavy vices such as bottled water or Big Macs. Works for me.

Related topic: the joys of low-carbon beer.