examinator,

Maybe I can put it more clearly. There are three effects operating. From fastest to slowest:

1. Over a period of 1k years the CO2 dissolves into the ocean, producing carbolic acid and thus raising the pH. This process continues until part of the ocean in contact with the atmosphere (the surface) is saturated, then "stops". This removes 25% of the CO2.

2. Over a period of 5k years, the acid water reacts with limestone, getting rid of the dissolved CO2 and replacing it with carbonate ions. The removal of the dissolved CO2 means it can be replaced by more CO2 from the atmosphere. The net result is the removal of another 65% of the original CO2. I don't know why this takes so much longer than step 1, although I gave a guess above.

3. The remaining 10% of the CO2 has to be removed by the geological carbon cycle. Ie the CaSiO3 + CO2 <--> CaCO3 + SiO2 thingy, whose rate is controlled by rainfall. That takes 100,000's of years.

pepper, one under god, manguel,

This thread is not about discussing whether the established science orthodoxy is right or not. It is about trying to understand it. I, and presumably the others here think taking a position without understanding what you are talking about is putting the cart before the horse.

The messages from Cater and his ilk are fairly simple. If doesn't take much effort to get your head around what they are saying. It turns out that the science is dammed complex. Understanding it is difficult and very hard to do on your own. This is why we are discussing it here - it is a group effort in trying to to grips with it.

To contribute positively, look at the lectures and make a honest attempt to understand it, ask questions here about the bits you don't understand, and then help others with bits they are having difficulties with.

If you wish to compare and contrast the climate science orthodoxy with other theories as to what is driving the planets climate, start another thread.

Rstuart,

Aha now I comprehend. Thanks.(Well better, anyway) :-)

Well said.. if scientists can't understand it, what makes you think anyone HERE can ??. Bob Carter is saying just that [ if you care to listen ] why should we send the planet broke [ or be dictated under one world government ] just because some "pointy heads " tell you they DO understand it - which is a blatant lie

pepper: "if scientists can't understand it, what makes you think anyone HERE can ??"

Do you take the attitude "it looks hard, so I won't even try" to every hurdle you face in life, pepper?

What prompted this discussion is the lecture series we are discussing here is for 1st year under-grads. Thus it is designed to be understandable by kids fresh out of high school. Except where he talks about his area of expertise (ocean chemistry) I think the lecturer manages to hit his target fairly well. Very well, actually. The bit about ocean chemistry is a difficult because like all experts, he does not realise how much background knowledge he has, and he fails to impart some of it.

As for generic "scientists", don't over estimate them. Just like any person who has done the same thing for decades, long serving scientists are very, very knowledgeable in their particular area. But remove them from that area and they flop about like fish out of water, just like us. I have said this elsewhere but I will repeat it here: if you doubt this just listen to Peter Doherty, Nobel laureate and Professor of Microbiology and Immunology at the University of Melbourne at the start of this video. http://www.abc.net.au/tv/fora/stories/2009/06/26/2609568.htm He is the very epiphany of a scientist, yet you will hear him say he finds papers outside of his realm of expertise dammed near impossible to read.

Dear rstuart and Examinator,

Sorry to be so dogged on this but I feel I have invested too much of my time to turn around with the summit in sight plus if I don't end up getting it nailed it sort of taints the rest.

Rstuart, you said >>This is why the layer above the troposphere, the tropopause is so cold - there is no water vapour in it to keep it warm. At least we have an answer for that bit.<<

Should it have read 'the stratosphere keeps it from getting colder as it should (since with pressure and therefore temperature easing that's what would normally occur)'? Even then it can't be the whole answer.

Do you remember from Lecture 9 the 'lapse rate' i.e. the rate at which temperature drops with pressure? If it were only set by radiation the change in temp over the change in height would be -16C per every kilometre upward.

Convection by itself drops that change in temp to -10C/km and Moist Convection (where the relative humidity is 100%) to -6C/km because of the release of latent heat as it ascends.

Cont

Cont

So here is the picture I'm getting. Light and IR radiation heat the ground and the air near it and UV heats the atmosphere from above.

Gases warmed at the ground level are sent aloft through convection aided by latent heat derived from condensing water vapour and by the fact that even though it is cooling it is still relatively warmer than the surrounding atmosphere.

The limit of this process is the point where no further condensation is possible to drive the convection, remembering it is dependent on pressure and temperature. When the gas is cooled and contracted sufficiently it then drops taking up latent heat as its newly formed ice crystals thaw into rain which further warm as they fall.

I think it might be the case that the only way for heat to get across this boundary is in the form of light including IR.

This cool layer is a separate to the one I had in my brain which consisted of concentrated green house gases. They do not really form a layer and are more just part of the gas composition of the troposphere. I also need to remember the difference between latent heat and temperature.

What they are doing is restricting the amount of IR that reaches the boundary to cross over and escape.

I'm hoping this makes sense.

David Archer says that the atmospheric layer must must be colder than the ground for a greenhouse situation to occur. My confusion was in thinking of this layer as where the GHGs resided. Not so.

Whew! Thanks for you patience.