Summary: Carbon dioxide is being released into the atmosphere nearly twice as fast as it is removed by Earth's carbon sinks, like forests and oceans.  Think of it as a bath tub overflowing.

To get atmospheric carbon levels back to manageable levels we not only need to turn off the tap by reducing emissions but also pull the plug by boosting our carbon sinks. We need to find ways to remove that excess carbon from the air.

This snapshot explores some key technologies that could move us below zero emissions.