To the atmosphere every year.
I good analogy are three big men laying pipe, plus a small boy. The first big man uses a backhoe to dig a deep trench. Then a second man puts in the pipe, and the third man uses a bulldozer to put the dirt back in the trench.
When the first man is digging up dirt, the small boy adds his little beach bucket of dirt to the pile. It amounts to 1/120th of the amount of dirt in the pile.
So between the dirt dug up, and the dirt replaced, this little added bit is well within the margin of error. Hardly noticeable.
Which is a good analogy to human CO2 production. And even the more scientific of the AGW advocates admit it. By ourselves, humans cannot do anything that can affect this scale.
The way they try to overcome this is to say both that planetary climate systems are so delicately balanced that even the tiny human contribution can throw it out of equilibrium, so that much greater *natural* CO2 producing systems will start producing more CO2, far beyond what we do; and/or the CO2 fixing systems are “maxed out”, and cannot absorb even a tiny bit more CO2 than normal.
That is, our tiny ‘lever’ of CO2 with force a much greater ‘lever’ of natural CO2 production, that will cause runaway natural CO2 production. While at the same time, the CO2 absorbing system will not be able to absorb any more CO2.
Which is nothing short of magical, religious reasoning.
“I cannot destroy the enemy nation by myself, but my gods will obey me, and they are powerful enough to destroy the enemy nation. Once I set them loose, they will do it all themselves.”
This is the Man Made Global Warming argument in a nutshell. People like Al Gore who think they are powerful enough to control the weather. What a Nimrod.