The good folks over at 350.org recently posted a terrific video of the graffiti artist Hans Hansen explaining the need to bring atmospheric CO2 back down to 350 ppm in visual terms.

350 from Hans Hansen on Vimeo.

Of course, to accomplish this, we need to also talk about climate-neutral cities. To get to 350, we need to first get to zero

Thanks to Robin Chase for the heads-up!