A major milestone.

For the first time, NOAA’s Mauna Loa observatory recorded an average daily CO2 concentration above 400 parts per million. Globally, we’re not yet at annual averages above 400, but this is indeed an important milestone. We’ve created 400.350.org to reflect on what this means, and talk about what we’re doing to cool the planet.

Please take a moment to read and share.


Freeze New Fossil Fuel Development

Governments meeting at the next climate conference must put their Paris pledges into action -- and action means no more room for new fossil fuel projects.
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