Increased CO2 levels are greening the Earth

[mdm]

Originally Posted by Captain Snooze

One of the interesting things I have read is that the tundra perma-frost is melting which will lead to a metric shitload* of methane being released which is a "better" greenhouse gas than CO2.

Yeah, CO2 is alone is pretty bad, but those positive feedbacks are really scary.


As you said, methane release from permafrost clathrates will likely be very bad.


Another thing is our old good water vapor. Which is also a potent greenhouse gas. The good thing about water vapor though is that the air cannot hold too much of it, any excess precipitates as rain, moves from the atmosphere to the ground and does not act as greenhouse gas anymore. This is unlike CO2 or methane for which there is no similar self-regulating mechanism.


But there is a catch: the air's capability to hold water vapor increases with temperature. So increased temperatures due to increased CO2 concentration cause more water vapor to remain in the air, which further raises the temperature, which causes even more water vapor to remain in the air (and more methane to be released from the permafrost), which further raises the temperature, and so on.