Have you measured your carbon footprint yet?

At our last meeting, Richard gave us a wonderfully clear report on how he has reduced his house's use of gas and electricity over the last 30 years.
At the end of the meeting we looked at a website http://www.carbonfootprint.com/calculator.aspx which is very easy to use (I did it in 10 minutes in my lunch-hour!) and gives a visual representation of your overall carbon footprint compared to a) other people in the UK, and b) what we need to aim for. All you need to know is how much you spend on gas and electricity and the annual mileage of your car.
It's tempting when your footprint comes out large (mine did!) to blame the calculator. But having chosen one, it's better to stick with it and see how you can start to reduce your footprint size!
The Guardian has compared different calculators at http://www.guardian.co.uk/environment/2008/feb/19/carbon.web - see Richard's comments below.
It would be interesting to hear your experience of using any of these calculators - do add a comment to this post.

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Hello Sally

You asked me last night if I could compare different carbon footprint
calculators. I made a start then found the Guardian has already done it:
http://www.guardian.co.uk/environment/2008/feb/19/carbon.web
As mentioned, personal footprints are bound to have limitations, because we
do not live isolated lives. Whenever we work or shop in a building shared
with other people, for example, or in the services we receive that are paid
for out of our taxes. In principle it may be possible to allot a carbon
content to every activity but it would get impossibly complicated.

Richard