| Augen said: As a professional in the field, how much does the percentage of carbon in our atmoshpere affect such things? |
Well, it's not my main field of expertise, but from what I read and heard we usually see a change of carbondioxide or methan concentration in the air _after_ a climate change has already happened (the methods of analysis might not be preceise enough to tell that with 100% certainty), so to see those rise before that sure is odd right now.
What we know from laboratory experiments is that those gases absorb infra-red radiation (heat) and radiate it again in a pretty much random direction, which is why the higher the concentration is in the atmosphere the longer time an infra-red ray on average needs to go from the earth surface to space and hence the warmer that area it bounces around in should become.
How much exactly is needed to make a grand impact on the climate is unknown and probably depends on many many other factors of the earth at that particular time. For example right now we have a great amount of ground in the artic regions of the earth, especially antarctica, siberia, greenland and canada, which has a great impact on the climate due to the fact that soil/rock can become much colder than water and easily is covered by snow/ice which creates a powerful albedo-effect, reflecting an influential portion of sunlight back without converting it to infra-red radiation. Additional factors ofcourse include solar activity, distance sun-earth, dust/sulfite air conc, aqueous vapor conc, ocean currents, maybe even cosmic radiation (an interesting study I read said it's a big factor in cloud creation and clouds ofcourse create an albedo aswell).
Popular speculation I read is that for how our earth is right now 400 ppm CO2 conc is the "point of no return" to a change to a hot house climate, a point we have reached last year, yet I'm personally not too certain about that.
In the past we had an ice house to hot house change at about 200ppm CO2 (it rose to 285ppm shortly after it got to be a hot house climate), but back then a majority of the landmasses were located near the equator.
