Data helps decisions. Humans are visual. There are a couple services that will help you visualise your carbon emissions:
TheCarbonAccount aims to show a complete picture of all your emissions.
The above graph is from my profile at http://www.thecarbonaccount.com/people/rakerman/
Both of them make a lot of assumptions. For example in Dopplr everything is air travel by default, you have to go in and manually edit each trip one-by-one if you want to change the travel mode, and the only other options are train and car.
In TheCarbonAccount I can't tell it that I buy green power from Bullfrog, or that I offset emissions, or that I take the bus to work.
This is an obvious killer app for Web Services. For one thing, I should be able to send from Dopplr to TheCarbonAccount. For that matter, my power consumption data from Bullfrog should also automatically feed TheCarbonAccount. Individuals should be able to build their own end-to-end carbon footprint chain, using SOA.
The heck with FriendFeed, where's my CarbonFeed?
(I'm pretty sure I Twittered this idea a while back, but I can never find anything in my Twitter stream again.)
January 18, 2008 carbon labelling