350
350 ppm of CO2 is where scientists believe we should return if we are to control the warming path we have set upon.
Today, across the planet 350.org is taking public action to increase awareness of the importance of that number. Check out their site to see inspiring pictures of people on every continent who want us to think today of how to return to that level of CO2 in the atmosphere. It is a number we may never see again.
Posted by Ray Hoff at October 24, 2009 10:37 AM