Global Warming - question for TM1 (and Others)

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I was wondering whether, according to thermodynamics (TM1 know more about this than any one else I know), whether global warming is actually possible?

Considering the earth as a closed system, it receives a fixed amount of solar radiation. It will also radiate a certain amount of energy. If greenhouse gassses act like a blanket, it would not (I think) reduce the energy radiated from the earth. Given space is a vacuum, heat transfer by convection is not an issue.

Would not the effect of greenhouse gasses be to average world temperatures? Colder climates get warmer (on average) and tropical climates get cooler (on average) ?

Unless .....

The earth became darker in colour. Then being more of a "black body" it would absorb more radiation, but would also radiate more itself?

Any thoughts?

Having taken a climatology class in this past fall, I can try to help answer here.

First - The amount of solar radiation that earth recives is constant, but the impact of said radiation depends on the angle of which it comes in, the more direct. Then there are circulation patterns, both horizontal and vertical the act to keep hot areas of the planet hot and cold areas of the planet cold.

In short, global warming isn't going to keep earth's temprature from evening out.

Here's more reading

http://en.wikipedia.org/wiki/Solar_constant
http://en.wikipedia.org/wiki/Jet_stream
http://en.wikipedia.org/wiki/Hadley_Cell
http://en.wikipedia.org/wiki/Coriolis_effect
http://en.wikipedia.org/wiki/Trade_wind
http://en.wikipedia.org/wiki/North_Atlantic_Oscillation
http://en.wikipedia.org/wiki/Arctic_oscillation
http://en.wikipedia.org/wiki/Pacific_de ... scillation
http://en.wikipedia.org/wiki/El_Ni%C3%B1o
http://en.wikipedia.org/wiki/Positive_feedback
http://en.wikipedia.org/wiki/Negative_feedback

thanks.

I don't mean evening out temperatures over the globe. But how would extra "insulation" make an object in a vacuum increase its energy levels (temperature being just a measure of energy).

I'm not saying that I don't believe greenhouse gasses are making climate changes, but I am having trouble seeing the energy level of the globe increasing.

TM1 is no expert on the subject. But his guess is that a large amount electromagnetic radiation (light, IR, UV ,etc)is reflected back into space. And carbon dioxide strongly absorbs in the IR band preventing much of that radiation from being reflected back into space.

http://www.carboncalculator.co.uk/scien ... ffects.php

It's all about IR energy. The earth re-emits some of the engery it recieves back into space as IR energy which is absorbed by CO2 and other gasses. When that IR is absorbed, the absorbing molecules gain that energy in the form a temprature increase. That temprature increase helps in turn, to promote a climate on earth that supports life. The whole system is an example of positive feedback loop. With the increase in CO2 levels over the years, it's feared by some that this feedback loop will get out of hand leading to a "run away green house effect".

That scenario IMO is very unlikely since there are other forces at play that will eventually step in to stop such a things from happening. The question IMO we need to be asking is how much damage will this do before it stops?

http://en.wikipedia.org/wiki/Keeling_curve