I came across a really great animation by NOAA that puts our current levels of CO2 emissions into the context of the last 800,000 years. It’s really quite alarming.
There is a great section on this blog site that talks about current levels of CO2, but there’s nothing like a video to drive the message home (I’ll actually add this animation to the page).
In case you were wondering where the data back to 800,000 years comes from, the answer is ice cores! When snow falls and compacts to form ice, tiny bubbles of air become trapped within the ice, storing a piece of the atmosphere at the time that the ice was compacted. Scientists can then analyse the actual atmosphere from hundreds of thousands of years ago by sampling these bubbles. Pretty amazing actually.