How much orange juice does it take to melt Antarctica?

Two articles in yesterday's New York Times help illustrate the extent to which that everything is connected. One, How Green is My Orange? describes Pepsico's efforts to determine the carbon footprint of its products. The short answer is that a half-gallon carton of  Tropicana orange juice is responsible for 3.75 pounds of carbon dioxide emissions. 

What are we to make of this information? In a perfect world, all products would be labeled with carbon footprint information, enabling us to choose products with the least environmental impact. But the factors that go into these calculations are so complex that it is extremely difficult to come up with a reliable number. At best, carbon footprinting could serve as a general guide, though with plenty of room for interpretation.

An article in the New Yorker last year, entitled Big Foot described the carbon footprinting campaign at Tesco, Britain's largest supermarket chain. Some of their findings were surprisingly counter-intuitive. The article explains, for example,  that

The environmental burden imposed by importing apples from New Zealand to Northern Europe or New York can be lower than if the apples were raised fifty miles away. In New Zealand, they have more sunshine than in the U.K., which helps productivity. . . That means the yield of New Zealand apples far exceeds the yield of those grown in northern climates, so the energy required for farmers to grow the crop is correspondingly lower. It also helps that the electricity in New Zealand is mostly generated by renewable sources, none of which emit large amounts of CO₂.

Similarly, if you live in New York it is greener to drink French wine than California wine. The reason? California wine travels across the US in trucks. This produces much more CO2 emissions than shipping wine across the Atlantic by boat.

While it is no simple task to compare the relative carbon footprints of the products we buy, we still need to find ways to reduce our personal, national, and global carbon footprints - a lot, and fast.

The second NYT article that caught my eye cited new evidence that even Antarctica is warming. Contrary to earlier reports that, while some parts of that icy continent were warming, others were getting colder, (which climate-change deniers have been fond of repeating, over and over) new research based on much more detailed measurements indicate that the entire continent is definitely warming.  This is leading to the breaking up of enormous ice shelves and the accelerating sliding of glaciers.

Orange juice is certainly far from our most carbon intensive consumable, but we should remember that virtually everything we do, everything we buy, everything we consume affects the size of our carbon footprint. I don't plan ever to visit Antarctica, but I like knowing that it is still there - something I'll think about next time I drink a glass of orange juice.