 So, we're now in a position to go back and have a look at the schematic showing all of the radiation contributions and compare the Holocene, which is a picture that is on the screen now, with that for 2013. The biggest difference that just stands out at you when you look at these numbers, and again they're in watts per square meter, is the global greenhouse gas back radiation. So that's the radiation coming back to the surface of the earth from the molecules in the atmosphere. It is 18 to 20 watts per square meter higher now than it was during the Holocene. There's also an increase in latent heat up to about 8 watts per square meter and in thermal outgoing up to about 16 per square meter, but the other important contribution to that's been made by the greenhouse gas climate change scenario is the amount of energy that's being absorbed by the atmosphere now. It is 12 to 14 watts per square meter more than it used to be. Some things have gone the other way. For example, there's less radiation being absorbed by the surface, there's less being reflected and the sensible heat contribution is less, but the amounts are very small and it would be interesting in time as we get a better handle on the uncertainties to see whether or not those amounts are significant. The net result of the dramatic increase in back radiation and absorption by the atmosphere is that the rate of forcing is no longer zero when averaged over a year. It is now 0.6 of a watt per square meter, almost one watt per square meter. Now, if you think of your solar panels, that's quite a lot of energy, one watt per square meter of excess energy that is in our atmosphere now compared with 50 years ago or 60 years ago.