Like a lot of his Hollywood friends, Jann Wenner professes a keen concern about global warming. Also like a lot of his buddies, Wenner likes to zip around the globe in a private jet. Does that make him a hypocrite? You be the judge!

This summer, Wenner reportedly plans to split his time between Europe and his vacation home in the Rockies. The rumor around Rolling Stone's offices has the boss, who's known for taking long holidays, only spending two weeks on the job between now and Labor Day. Having returned from an idyll in Greece for his son's wedding , the wee mogul is off to Sun Valley, Idaho, for a spell, presumably in the company of his boyfriend, Matt Nye, and their one-year-old son. Assuming he only makes one round trip in each direction, that's a total distance of around 14,000 miles.

[Full map after the jump!]

Wenner's Gulfstream jet has an optimal cruising speed of around 493 nautical miles per hour. (That figure, and the ones that follow, are based on calculations for a Gulfstream IIB, Wenner's longtime ride. In fact, according to sources, these days he may fly the slightly larger Gulfstream IV; a Wenner spokesman did not reply to calls for comment.) At that speed, the plane would produce around 80 tons of carbon dioxide during the 20-hour round-trip voyage between New York and Athens, and another 33.6 tons flying between New York and Sun Valley. Fun fact: According to the Environmental Protection Agency's emissions calculator, you'd have to drive a Hummer H3 200,000 miles to generate the same amount of carbon.

You might think a guy who hosted a screening of An Inconvenient Truth, and who recently edited a "green issue" of Rolling Stone, printed on carbon-netural (though not recycled) paper, would be a little more sensitive to his own emissions footprint. Jann, if you're not going to retire the jet, perhaps you'd at least consider laying out the $1,136 it would cost for the equivalent in carbon offsets.