350.org is an international campaign dedicated to building a movement to unite the world around solutions to the climate crisis--the solutions that science and justice demand.

350 parts per million CO2 in the atmosphere has been identified as the upper limit that can be tolerated for our survival. This figure has been established by Jim Hansen of NASA and emdorsed by Rajendra Pachauri, head of
the IPCC and the UN's leading climate scientist. The campaign wants world leaders to agree a global plan to work towards this target of CO2 in the atmosphere.

In order to unite the public, media, and our political leaders behind the 350 goal, we're harnessing the power of the internet to coordinate a planetary day of action on October 24, 2009