But distance is only part of the equation; the mode of transport matters, too. For example, a recent study (PDF) by wine expert Tyler Colman and sustainability engineer Pablo Päster has gotten a lot of attention for proposing that people living east of an imaginary "green line"—which runs roughly through Kansas—would be better off buying wine sent by container ship from Bordeaux, France, then trucked to its final destination, than wine trucked all the way from Napa, Calif. That's due to the fact that container ships are generally considered cleaner modes of transport, which makes up for the longer journey. By the same token, shipping by rail rather than truck would push the green line eastward. (Colman and Päster's study focuses on transportation impacts and doesn't account for regional differences in viniculture or efficiency measures at the winery.)
In any case, one of the easiest, most straightforward things you can do is look for wine that comes in lighter and larger packages, wherever it originated. Some wineries, for example, ship their libations in bulkcontainers, to be bottled closer to the point of consumption. Others are reducing the amount of glass in their bottles—a practice known as "lightweighting." TetraPaks—those plastic- and metal-lined paper containers that soup and soy milk come in—get green points for being less energy-intensive to make and ship,though they lose a few for not being easily recyclable. Finally, there's the much maligned wine-in-a-box, which is actually a vacuum-sealed plastic bag inside a cardboard container. It has all the benefits of TetraPaks as well as a more promising afterlife, since the cardboard can be recycled. (The plastic, though, is probably headed for the landfill.) Plus, once the box is opened, the wine inside stays drinkable for much longer than it would in a bottle. So if you want to lessen the impacts of your drinking, get ready to swallow your pride, as well.
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