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It's clear to me you haven't read or thought about actual climate science. You just pick up and regurgitate talking points from alarmist blogs and repeat the same inaccuracies, mis-comprehensions and confusions they do. Then, rather than admit you haven't understood something, ask for a clarification, and ask for further assistance if needed, you create a diversion such as making a false accusation. You've done it several times recently, and you never come up with anything to support it, but just create further confusion to kick dirt over your tracks.
Here's the sequence. You asked:
I have question for you. At what point does shortwave become longwave? I mean why wouldn't shortwave interaction with areosals create what would be apparent longwave emitting from the planets surface? Surely these particles heat up at some level and emit longwave that could be mistaken for earth-born longwave when they are strictly from the atmosphere. The point here being that if that's the case they could show a false increase. That was where I was going with my previous post.
Edited by wildlife on 09/22/2012 01:00:07 MDT.
And I replied:
Rog Tallbloke (tallbloke) Re: OK Rog on 09/22/2012 03:01:06 MDT
The boundary between 'short wave' and 'long wave' is actually an overlap in terms of what it means for the climate system. This is because Approximately 16% of incoming solar 'shortwave' is absorbed in the atmosphere by water vapour and the radiatively active trace gases such as co2 and ozone and methane. Also, aerosols of various types absorb solar energy directly, or reflect it.
There's very little water vapour and co2 in the stratosphere, where ozone absorbs strongly and actually causes the stratospheric temperature to rise with altitude, whereas temperature falls from the ground to the top of the troposphere where it meets the stratosphere. The rate it falls at is called the environmental lapse rate, and is around 6.5K per Km on average. If there was no moisture in the air, it would fall at around 9.8K/Km. This is called the dry adiabatic lapse rate, and it is determined by the equation
-Γ≡ dT/dz = -g/Cp
where g is gravity and Cp is the heat capacity at constant pressure. dT/dz is just the differentiation of delta Temperature divided by delta altitude in the units K(degrees Kelvin)/Km(kilometers).
The AGW theory is that adding more co2 will increase the heat capacity of the atmosphere (because it absorbs radiation), and so raise the 'effective altitude of emission'. This in effect enlarges the troposphere, and so when the lapse rate is back calculated from the Top of Atmosphere (TOA) to the surface, the temperature has to be larger than before.
But this relies on the assumption that 'everything else remains equal', and we don't know that's so. The Earth does not absorb or radiate long wave as a perfect 'black body' according to the Stefan-Boltzmann equation, because it presents a hemispheric surface to the incoming solar radiation, and is covered in a fluid (the oceans) which are shifting heat from the equator towards the poles. The rate and efficiency with which that happens depends on cloud cover and many other variables, and so there are multiple ways in which the emission of long wave back to space can vary, apart from a change in average surface temperature. This is summed up by an effect known as Holder's Inequality - the way heat is spread out.
So, for example, one of the ways Earth reacts to a change in the incoming solar energy is to alter the latitudinal position of the jet streams, which in turn alters cloud distribution.
The modelers try to reduce all this complexity by considering the measured radiation at various latitudes. And this tends to lead them to think in terms of changes in the TOA radiation as the driver of the system. But this is a mistake, because the main driver of the shifting of energy from equator to poles is not radiation, but the latent heat of vapourisation and condensation of water, and the convection which carries the water vapour up from the tropical ocean, and the currents which move warm water polewards under cloud which is changed by the SST (Sea surface temperature), but also changes the SST. All these things interact to affect each other, and it's fiendishly complicated to tease out the cause and effect. It's better to consider it as an interacting set of cybernetic feedback loops.
Here's a quote from the general circulation course at Chicago university:
"Considering the energy balance of the atmosphere-ocean system, the variation with latitude of the long-term average net radiation at the top of the atmosphere implies energy transports inside the system. These transports are produced by the circulations of both the atmosphere and the oceans, and we can regard the general circulations of the atmosphere and oceans as a “response”(for the purpose of modeling) to this pattern of net radiation. An important point, however, is that the distributions of the albedo and the outgoing longwave radiation are determined in part by the motion field (convection dominated general circulation). It is thus a drastic oversimplification to regard these fields as simple forcing functions; they are bound up with the circulation itself." http://kiwi.atmos.colostate.edu/group/dave/at605pdf/Chapter_2.pdf
My parentheses.
And then you make this false accusation:
dan mchale paranoid on 09/22/2012 12:19:38 MDT Well, at least you pointing out that you were not really answering me directly but just copying at me from your website about the CO2 and H2O vapor frees me from the paranoid level. Your answer was not considerate.
What I have done twice is take long answers I've given here, and turned them into posts for my blog afterwards. But I have never fobbed you off with a cut'n'paste from my blog to here.
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