Thrift, piety, and guilt conspire to give me good environmentalist habits. I bicycle to work every day. I periodically walk around our house, turning off lights and computers and the set-top satellite receiver on our television. Our tiny suburban lot has 10 trees on it, half of which we planted since moving in.

But I'm still a carbon-emissions nightmare, because last year I flew almost 50,000 miles, 40,000 of them for work. According to this carbon calculator (the only one I could find that lets you simply enter a total number of air miles), that means I produced 18.4 tons of CO2 by jet travel for my job. The site for An Inconvenient Truth says that the national average is 7.5 tons a year, so with work-related flying alone (i.e., irrespective of taxis, trains, and so forth, let alone my entire personal production of CO2), I've produced about two and a half times the ordinary American's exhalations. No matter how much I also pedal and plant, I'm a global warmer.

Nor am I alone, or even the worst offender. Almost since the beginning of air travel's commercial availability, academics have been leaving on jet planes. The opening of David Lodge's Changing Places shows why, as well as why it's so absurd:

“High, high above the North Pole, on the first day of 1969, two professors of English Literature approached each other at a combined velocity of 1200 miles per hour. They were protected from the thin, cold air by the pressurized cabins of two Boeing 707s, and from the risk of collision by the prudent arrangement of the international air corridors. Although they had never met, the two men were known to each other by name. They were, in fact, in process of exchanging posts for the next six months....”

To develop these airplanes and fly them safely humankind has spent innumerable hours and dollars and even lives, has waged wars and negotiated treaties, so that a couple of close-readers can shoot in opposite directions across the globe and spend half the year lecturing to a different set of pupils and provoking a different group of colleagues.” (And in Lodge's book, sleeping with each other's wives. Which real academics never, ever do.)

Yet, as Lodge also indicates, there's a reason for it: These two men know each other by name but have never met. Though two professors toil in the same field--though indeed they be intellectual intimates, joint proprietors of the same scholarly turf, the lines of their arguments crossing in quarrels and comity so often that they can no longer imagine what they would have said had not the other provided a constant counterpoint to their every professional utterance--they may never meet in life, only in footnotes.

And if your business is discussion and argument, think how woefully inefficient this mode of interaction seems, how frustrating! If you've ever tried to nail down an appointment by e-mail with someone, going back and forth several times only to pick up the phone in exasperation to speed the haggling over schedules, you have a microscopic sense of the enormous, glacial aggravation the normal mode of academic debate entails. You write a book or a journal article, which takes years. Getting it into print takes another year. If you're lucky you'll then get an informal e-mail response or (rarely) a letter. More often, though, a prudent interlocutor will prepare an equally sluggish reply, for a reply time of another two years. If you're lucky. It makes a square-rigger engagement look positively zippy.

So of course we fly: to conferences, either to give papers or to do preliminary screening of job applicants; to other universities, to give invited lectures; to take up temporary appointments in distant places just so we can, however briefly, talk at speed with our closest colleagues whom we otherwise never see.

But now the upswell of concern over global warming alerts us we cannot afford so much of this evidently essential interaction. What can we do?

We can of course carry on informal intellectual exchanges by e-mail, and many of us do -- as Lodge’s characters could not, in the old days. I could scarcely have pursued my scholarship during my three years living abroad without the Web.

But e-mail exchanges are private and so not in the spirit of scholarly discourse. We can therefore use more public fora, particularly blogs, for provoking higher-speed, but still substantial and somewhat prepared, academic discourse.

And we can generally publish more in electronic media, including online journals, making formal interaction more speedy. (Even so, the major hold-up in journals is often not printing, but peer review: but that's a different hot-air-related subject that might also stand e-improvement.)

For this shift to occur, we academics need to agree that we can read digital print, too. The Modern Language Association in 2005 rather shockingly found that 20 percent of the departments they surveyed thought digital publishing, even in peer-refereed journals, didn't count as scholarly output, and 40 percent had no experience evaluating such digital publication.

We need to agree that we can stand to watch either other on video through the Internets. More conferences and lectures must occur online, as the Miller Center of Public Affairs series do.

We probably can't give up glad-handing and personal job interviews altogether: evidently we read an awful lot of each other in these interactions. But if we're living the life of the mind, we need to do it as much as possible in our heads, and move from the mindset of "Can Blogging Derail your Career?" to "Blogging Can Save the Planet!"