But the other thing about this graph is that it shows that the trend of CO2 in the atmosphere is going inexorably upwards. If we look back at over about the last 800,000 years or so, you'll see that CO2 has actually been rising and falling on a fairly regular basis, moving between about 180 and 300 parts per million. So let's take another look at this graph. And we can see that since the start of the Industrial Revolution, when CO2 was about 280 parts per million, its been going up at an exponential rate. In fact, in 2013, it was measured at 400 parts per million at Mauna Loa for the very first time. And this is not just a record for Mauna Loa. It's actually a record for at least three million years, since the Pliocene. We have now been putting a lot more CO2 into the atmosphere than plants can take out.