400 ppm CO2: What It Means | cChange: Transformational Responses to Climate Change | Scoop.it
Learn about what the number 400 means for our future. On May 9th, for the first time ever, the world's most important CO2 monitoring station recorded daily CO2 concentrations above 400 parts per million -- the highest levels found on earth in over 5 million years.Already we're seeing the deadly effects of climate change in the form of rising seas, wildfires and extreme weather of all kinds, and passing 400 PPM is an ominous sign of what might come next.The safe level of carbon dioxide in the atmostphere is 350 parts per million, but the only way to get there is to immediately transition the global economy away from fossil fuels and into into renewable energy, energy efficiency, and sustainable farming practices in all sectors (agriculture, transport, manufacturing, etc.).

While the level fluctuates seasonally and varies across different latitudes, this is yet another sign that our dependence on fossil fuels is out of control.