Just let me finish and say this. If the world as a whole cut all emissions tomorrow the average temperature of the planet is not going to drop in several hundred years, perhaps as much as a thousand years because the system is overburdened with CO2 that has to be absorbed and that only happens slowly.
Someone is going to have to explain this one to me, because first of all 400ppm is bugger all for starters and my understanding is the concentration falls a few % every northern hemisphere summer (more trees in the northern hemisphere capture co2 than what increases) and it is the southern hemisphere summer where the actual increase occurs each year
