350.org is an international campaign that’s building a movement to unite the world around solutions to the climate crisis–the solutions that science and justice demand. 350 is the most important number in the world! Scientists say 350ppm is the safe upper limit for carbon dioxide in the atmosphere. Find out more on the global site, 350.org.

350.org is building a global grassroots movement to solve the climate crisis with online campaigns, grassroots organizing, and mass public actions led from the bottom up by thousands of volunteer organizers in over 188 countries.

350 means climate safety. To preserve our planet, scientists tell us we must reduce the amount of CO2 in the atmosphere from its current level of 392 parts per million to below 350 ppm. But 350 is more than a number—it’s a symbol of where we need to head as a planet.

350.org works hard to organize in a new way—everywhere at once, using online tools to facilitate strategic offline action. The organization is a laboratory for the best ways to strengthen the climate movement and catalyze transformation around the world.

In October of 2009, 350.org coordinated 5200 simultaneous rallies and demonstrations in 181 countries, what CNN called the ‘most widespread day of political action in the planet’s history.’ On 10/10/10, they organized the “Global Work Party” — a day of climate solutions projects, from solar panel installations to community garden plantings–and changed communities from the bottom up with over 7000 events in 188 countries.

In 2011, they mobilized people power in every corner of the planet. In September, they organized “Moving Planet” — a massive day of action to move beyond fossil fuels. The group also helped lead the fight to stop the Keystone XL tar sands oil pipeline — a relentless campaign that ended in improbably victory.

If an international grassroots movement holds our leaders accountable to realities of science and principles of justice, we can realize the solutions that will ensure a better future for all.