The Port of Portland is expanding PDX's flight capacity with nary a whisper about the pollution those extra flights will generate. Shouldn't we worry less about bike lanes and more about willy-nilly jetting around the globe? —Ken S.

Not to bum you out, Ken, but you've pretty much put your finger on the reason we're all doomed. Not because of air travel per se, but because of a principle I just now decided to call Dr. Know's Law of Ecological Hypocrisy: People will follow their environmental conscience, unless it requires giving up something they really want.

It's all very well to pat yourself on the back for composting your cantaloupe rinds and doing without a straw at Lardo, but let's be honest: When was the last time you heard of somebody forgoing a two-week vacation in Jamaica just to make things a little easier on ol' Mother Earth?

Make no mistake; air travel is just about the least green thing you can do. (Pardon me as I climb atop my Dr. Bronner's 100% Hemp-Oil Soap soapbox.) While cars, electricity-generation plants and home heating and cooling systems have all made substantial progress in reducing their carbon footprints over the past half-century, modern air travel still blasts through almost as much fossil fuel as it did back in the "coffee, tea or me?" days immortalized in Mad Men.

How bad is it? Well, a trip for one from PDX to Jamaica and back represents right around 10,000 pounds of CO2, roughly the amount emitted by the average American's car in a year.

At the risk of being tendentious, I can't help noticing that jet-setting coastal elites who sneer at the environmental backwardness of "flyover country" are probably doing more damage by flying over that country than all the F-150s in Missouri put together. Elon Musk alone logged 150,000 miles in his Gulfstream G650ER last year, which comes to around 2.3 million pounds of CO2. That's 230 zero-emission Teslas he needs to sell just to break even.

Of course, a lot more than 230 Teslas were sold in 2018, so Musk is probably in the clear. Your trip to Jamaica should be fine also—just invent cost-effective, sustainable cold fusion while you're there and all will be forgiven.