In today's G2 section of the Guardian newspaper, Mark Lynas explains how we can each calculate - and then reduce - our carbon footprint. It's quite a complex calculation and one that requires a good memory - and brutal honesty - about a year's worth of shopping and travel, as well as some proficiency with a calculator. But while it may be hard work, the act of sitting down and considering how your actions affect the environment could help you save both money and energy.
It's certainly likely to raise some questions about your carbon footprint. Fortunately, Mark has agreed to answer them. Post your questions here by 5pm on Thursday January 25 and the best ones will be answered on the Environment section of Guardian Unlimited next Tuesday.
And as if getting the answer to your eco dilemma wasn't enough, you could also win a copy of Mark's book, Carbon Counter.
