I'm not some paragon of green virtue. I don't have solar panels on my roof or a wind turbine in my back garden. But as I wrote my book Six Degrees and participated in the filming of National Geographic's "Six Degrees Could Change the World," I grew increasingly aware of the need to keep my own greenhouse gas emissions to a minimum. Not only because it's so easy to be called a hypocrite (it has happened to Al Gore), but because I wanted to be able to prove to myself that a low-carbon lifestyle was not only possible, but desirable too.

We'd already gotten rid of the car a couple of years previously. My wife and I still use cars on occasion, but having to go and hire one first is a significant disincentive. Most of the time, I get around by a combination of bike and train. Luckily, both are pretty convenient here in Oxford, England: We're reasonably well-endowed with cycle paths, and the train station is only fifteen minutes away. I travel a lot by train though, doing lectures and visiting low-carbon community projects up and down the country, so even this adds up in terms of carbon output.

International travel is, for most people, the most difficult area to tackle. I've had a rule against flying for holidays or other personal use for nearly a decade, but that doesn't mean I haven't been on a plane. Far from it. My work on climate change has taken me around the world, reporting on global warming impacts from flooded Pacific islands to disappearing Peruvian glaciers in my first book High Tide (Picador, 2004).

Most recently, I went to Bali for the December 2007 UN climate conference. I'm also travelling to the United States this month to do promotional work for Six Degrees. Should I stay at home and save the carbon? Ultimately, there is always going to be a trade-off: In order to have an impact on this urgent issue, writers, speakers and campaigners need to be able to travel to spread the word—despite the emissions of greenhouse gases caused in doing so.

I've made sure, however, not to take any short-haul flights. In recent years, I've travelled from England as far as Norway, Sweden, Switzerland and Germany—all by train and boat. I do think, though, that the focus on aviation is in danger of going too far. There are much easier ways to cut back on emissions than never to fly again. For most people in cold climates, space heating is probably their biggest use of energy. I've put in a wood-burning stove, which covers 95 percent of our heating needs. I even cut the wood myself locally, so there are no emissions from transport here. (For the most eco-friendly ways to use a wood-burning stove, see "Is Burning Wood Greener than Burning Gas?"). Several people on our street also have stoves (we're in a village on the edge of Oxford) so we're setting up a community group to coppice some nearby woodland.

We've also switched to green electricity, so all the power we use at home is 100 percent renewable. I can't believe more people don't do this—it only takes five minutes (for tips, see "Convert to Green Power” ). And we've declared ourselves a low-carbon community too, something which seems to be getting increasing numbers of people involved. There are hundreds of other communities going green around the country too, and knowing that so many other people are making the same commitment is what keeps me both inspired and determined to succeed.

Mark Lynas, author of Six Degrees