Dear Umbra,

I was wondering if there is any information about the average CO2 emissions from human flatulence. My friend (and I really do mean my friend, I’m not just trying to hide that it’s for me) has a birthday coming up, and I think it would be a fun and meaningful gift to get him renewable-energy credits for his CO2 emissions. Thanks!

Ashland, Wis.

Dearest Matt,

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When I first began writing this column three years ago, I thought I’d have to fake questions, but curious humans like yourself make that quite unnecessary. (In general, I believe advice columnists don’t ever have to invent questions. Save Walter Scott, in Parade. I mean, c’mon.) So I don’t make up questions, but I do follow my editor’s bidding, and my editor is enamored of this query.

It’s your birthday! Make some noise!

Matt, there aren’t too many studies on this kind of thing. Which is exactly why researchers in England embarked upon one. They fed human volunteers their regular diet with an addition of 200 grams of baked beans (bleagh) and then gathered and analyzed their gaseous emissions. The range of CO2 emission was 25 to 116 milliliters in 24 hours, about two to three shot glasses worth. Not very high. Our digestive process is less gaseous than that of cows, the notorious methane producers, because we have a completely different stomach arrangement and different intestinal flora.

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No worries, you can still make a fart-based eco-humor gift. It doesn’t really matter how much methane or CO2 your “friend” produces, the concept will still be humorous and a great Top This! What Can You Do? project.

First, choose a green-tag company that supports wind development. (Get it? Ha ha.) For example: NativeEnergy credits go toward wind-turbine development and methane generators on dairy farms. (Plus, the company is run out of Charlotte, Vt., a town close to my editor’s heart.) The company offers gift certificates and all-occasion cards, which explain what energy-trading credits are and which projects you’re supporting. Then, of course, you must get a separate, tacky card — though I sense you might have thought of that already — in which you write something like, “Since you’re an above-average contributor to wind-based climate pollution, I figured I’d better support clean wind on your behalf.”

Give him the card in front of other people. One, it will be funnier, because farts are funnier in group settings. Two, you will need to explain the card, the green tags, wind power as an economic-development engine, and where you found such a sophomoric yet meaningful gift. The more people who hear you explain all of this, the more likely one of them will follow your lead and give green tags as a gift or buy them to offset their own emissions.

By the way, NativeEnergy is only one of many green-tag outfits, so look around. I just picked it to further suck up to my editor.


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