Calculating carbon footprints has got to be one of the hardest jobs in the world. Carbon release has become the prime measure of our environmental unfriendliness and, like it or not, we’re going to be punished for it.

Hold on, what am I talking about? We’re already being punished for it.

I tried to find a low carbon car for me and my wife. But for personal reasons I won’t go into here, we ended up with one that squirts out 139g/km. It was the only car that matched our needs (and our budget) and it put us well above the 120g/km ceiling that the powers-that-be would prefer us to use. Still, we use the Tube a lot.

Whichever way you turn these days, you run into uncomfortable environmental equations. Is it better to work from home or from the office? Home working offers a better lifestyle as well as lower fuel consumption from fewer commutes and less office space. But what if no-one’s usually at home? You’re then using the heating, lights, space, equipment, toaster...

I guess all these things can be worked out but what about a lot of supposedly free things on the internet? What about an avatar in Second Life? A few years ago, Nicholas Carr calculated that one avatar had the same carbon footprint as the average Brazilian.

And what about YouTube videos that are watched by the million? The sillier they are, the more the wires hum. Videos that educate or inform strike me as okay. I even watched Al Gore’s TED movie yesterday. But watching people speed up and down motorways or use dogs as bowling balls does not seem an environmentally friendly way to proceed. Although I have to say that the bowling ball dog was very funny.

People accuse me of being curmudgeonly, of taking the fun out of life. They could be right. But when the fun is manufactured purely for the purpose of grabbing eyeballs or fame, I can’t help wondering where we’re heading.

If we really are in the grip of death by carbon, shouldn’t we all be taking things a bit more seriously?

Shouldn’t we be on a war-like footing and restricting our activities to those that either improve us or help to save the planet?

As Gore himself says, what’s missing is a sense of urgency. He’s right. Even though he can show us pictures of ice caps vanishing, we still drive our cars, go to Second Life, watch daft YouTubes and, it has to be said, indulge in all manner of largely pointless but power-gobbling social computing activities.

If those activities replace travel, terrific. If they enable people to push forward with projects, wonderful. But if they just exist so people can boast about how many friends or followers they have, you have to start wondering about the point of such activity.

The answer, surely, has to be that the carbon bit will, one day, have to be paid for. Gore sees this as the great tool for control: a tax on carbon. He even suggests that green tax could replace income tax, which seems a more equitable approach than just adding a carbon tax to all the others we’re prey to. The problem comes in measuring the tax liability: income is easy, carbon is hard.

But if it happens, it could mean that free internet services will struggle. Their energy costs will shoot up and, because there are so many of them, perhaps their sponsorship and advertising revenues will not be able to match the rise in costs.

Then they’ll have to take the huge step of charging users. That will sort the men from the boys. And, who knows, it might result in a huge reduction in IT’s carbon footprint.