Tuesday, April 12, 2011

Livin' in a Spherical World

And I am a Spherical girl. Not! Though sometimes I am told I am getting in touch with my feminine side. The really piss poor drawing is an exaggerated depiction of why I think models should get in touch with their spherical side. The big round circle is the Earth and the smaller circle is a CO2 molecule shooting nasty radiation in all directions. The first arc is the top of the troposphere and the second, the bottom of the stratosphere also known as the ozone layer. In this exaggerated drawing you can see how the horizon the pistol packing CO2 molecules sees is below its horizontal axis. That area between the horizontal and the horizon is not included in the models because in the real world the Earth is so big that it can be assumed to be a flat disc. In many cases the CO2 molecule is also assumed to be a smaller flat disc so that only up/down radiation is considered. Most things considered, that is not a bad simplification. Since I think I am considering things not fully considered, I think that assumption can be improved upon.

To my thinking, every small degree below horizontal means something. How much I don't know yet, but I think it is worth considering. If you go up in the sky you will start seeing the curvature of the Earth. Everybody knows that. On my charts light houses and towers have their heights listed and the distance you can see them in clear conditions. A 150 foot tall light house can be seen at 14 miles while a boat at the lighthouse can only be seen at about 4 miles. In the top of the lighthouse the Earth still looks flat you can just see more of it. My little, no where near to scale, CO2 module could see further. My little CO2 module is near sighted though. On an fairly humid day, he can only see about 5 to 10 meters. That is because the little CO2 molecule sees all the H2O molecules surrounding him. They are blocking his view.

The higher the CO2 molecule gets, the better he can see because the stupid H2O molecules are afraid of heights. Once the CO2 molecules get to the top of the tropopause, he can see a lot better up and to all sides. He can see better looking down. At this point, the H2O guys are almost gone. There are still about the same number of other CO2 molecules, a lot fewer, but still some N2 and O2 molecules, and an increasing number of O3 molecules. Because of his bad vision, Mr. Co2 can't see the N2 and O2 molecules worth a dam. This is also where Mr. CO2 and his buddy infrared (IR) heat packets start doing their thing for real. The little IR packets excite the CO2 molecules. The CO2 molecule can git rid of the IR heat packet by bumping into the molecules he can't see, passing it off to one of the other CO2 or O3 molecules and if it can't pass it off or misses the inert molecules, it can just puke the little IR heat packet out.

The CO2 IR heat packet is special. It is at one pretty specific wave length. When the inert molecules bump around, they get hot, but their IR heat packets aren't so special. They have a wider variety of wavelengths. These not so special packets can shoot out to space easily in any direction but down. The not so special IR heat packets are going to keep on doing their thing. It is only the special IR heat packets we need to worry about.

If you can imagine the CO2 sticking its little arms out and spinning like an ice skater, every direction above its arms has a shot at the depths of space. The IR heat packet has the best shot straight up, because there are fewer things to run into. As the angle decreases from vertical, the odds of hitting something increase. The flat disc model does just fine as long as the odds of the IR packet heading back to Earth is the same below the arms. The further Mr. CO2 goes up, the more likely there will be more shots to space below the arms. The two dimensional models consider that and use the average with height to compensate. The question is how well do the two dimensional models deal with the interactions of the IR packets with other molecules at the boundary of the water vapor?

The IR packets the water vapor capture may or may not be as special as the CO2 molecule IR heat packets. If Mr. CO2 is excited by either an IR packet or banging into another molecule, the packet it releases is special. When water vapor bangs into another molecule, the IR packet it releases can be of a wider variety of wavelengths. It may very well be that the water vapor heated by the special CO2 packet will release another special packet, but part of the radiation situation is that more special packets will cause general warming, which means more molecule banging which may cause the release of more not so special IR heat packets. My theory hinges on the slightly below horizontal special IR heat packets causing a greater percentage of not so special heat packets being generated at my imaginary water vapor layer. That is the antennae ground plan analogy, which I think is a major part of the potential Tropopause Sink.

The only thing that I know of that backs up this theory, is the variation in Troposphere temperature. The Troposphere temperature can be up to 30C cooler in summer in the tropics than normal. If the Tropopause had the idealized no change in temperature from an average altitude of 10K to 20K, I would not even consider my theory. I would expect the constant temperature region to grow narrower in the summer with increased heat flow and wider in the winter. I would also expect the constant temperature region to grow narrower with increase CO2 and its expected warming potential. That would conform with the expected change in the lapse rate.

In the real world the lapse rate seems to have a mind of its own. Much cooler temperatures like -90C versus the approximate -60C normal range happen all the time and should represent increased IR cooling. Does this represent a natural feedback to atmospheric warming? I haven't a clue. Before I even waste my time trying to create, or Tom Sawyering someone in playing with a modified radiation module, I need fairly reliable measurements of the temperature profile of the tropopause with time, say from 1950 to today. I am positive that that data will be extremely noisy or I would have already read more about the tropopause sink instead to the stratopause sink. The tropopause sink is considered weak, from the one paper I saw, so I need to see why they came to that conclusion.

This paper by Randal, Wu and Gaffen, shows stuff going on from 1957 to 1997 in the Tropopause. The data is very noisy, but it shows the complexity of the Tropopause seasonally, inter-annually and spacially. Accurate time series analysis is way beyond by pay grade and educational background. I am more a big picture kinda guy than a bean counter. So I have probably bitten off a hell of a lot more than I can chew. So you can expect a lot more face plants while I brush up on the openoffice spread sheet I am stuff using and not very familiar with, to get rough plots of available data, then while I am struggling with basic time series analysis, I am sure I will make more bone headed screw ups. But what the hell, I like puzzles.

This is the trend of the TTS from the RSS/MSU and AMSU satellite data. As you can see this is very little trend. You can clearly see the 1998 El Nino and the drop off.

This is the global anomalies for the Tropopause/lower stratosphere. Pretty boring except for the northern hemisphere and a few little blotches.

This is the TMT or middle troposphere. Still not a big trend, but you can see more stuff happening. The lower troposphere (not shown) compares well with surface temperatures. The surface/lower troposphere have a lot more stuff happening. There is a lot more natural variability down here. Whether that natural variability averages out, I don't know.

Finally, this is the lower troposphere. One thing that is interesting is Antarctica. In the TTS, tropopause lower stratosphere you can see some warming over the Peninsular at the bottom of South America. That is supposedly due to Rossby waves, perturbations in the polar vortex. The North Pole gets a lot more of that kinda stuff. These things are more a sign of natural variation than CO2 induced warming. Of course these waves may be intense because of CO2 warming, but it is hard to tell that from this data. The main point, is that the TTS is very stable with just a hint of warming. It makes the same rapid up excursions, with more gradual recoveries. That is pretty common in climate, it takes longer to recover. The TTS recovery is a lot more rapid than other layers, at least to my eyeball.

As usual, I may come back to this to make corrections and add notes.

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