Wednesday, October 27, 2004

Atmospheric Physics Part II

One of my favorite characters was Richard Feynman. He may be familiar as the individual serving on the space shuttle Challenger investigation board who demonstrated the key flaw by squeezing an o-ring in a C-clamp and immersing them in ice water. (His minority opinion to the final report of that commission foretold the failings leading to the loss of the Columbia.) He was most remarkable for his curiosity.

In his book, What Do you Care What Other People Think? he talks about his father, the uniform salesman. He described seeing people bowing before an authority figure, such as the Pope and asking his son, “What is the difference? … The difference is the hat he’s wearing.” Often, people make a plea to the putative authority of their supporters. In just this manner, the TTAPS authors held a conference filled with notables (e.g. the uniforms). Francis Crick got his Nobel Prize for the discovery of DNA, but does that qualify him to peer review atmospheric physics? So the conference became a frenzy of ever more heated speculations on how a “Nuclear Winter” could harm the environment. They did not get a peer review!

It is interesting to note that Saddam Hussein provided the real world peer review by lighting the Kuwaiti oilfields. Here the TTPAS predictions started to break down. There was no long lasting temperature inversion. While the effects were a local environmental disaster, they did not support the theory.

This issue of an inversion is another one where the ordinary citizen’s intuition might fail him. The scenario was that soot from the fires would absorb sunlight and get heated. The hot air would rise and cause an inversion that natural forces would not break. The novice might think “heat rises” and accept this idea. But does heat rise? Do you have a heated ironing board and an unheated iron so the heat rises into the fabric? Do children paint mountains with deserts on top? Or was the book called The Snows of Kilimanjaro? In the real atmosphere as heated air rises it expands and cools (adiabatic cooling). Whether it continues to rise is influenced by its humidity relative to the surrounding air. Water vapor has a high heat capacity compared to dry air. We know the soot bearing air has moisture as water and carbon dioxide are the primary products of combustion. As the air rises, the water gets closer to the condensation point and forms clouds. Condensing water in droplets changes the volume and temperature of the air. This affects the buoyancy relative to the surrounding air and creates lateral movement. You see this effect on days with high solar heating that lead to cumulus cloud formation. Careful observation will reveal that the air rises into the bottom of the clouds and descends between clouds. This is the artifact of the horizontal flow. Yet this two-dimensional flow is beyond the capability of the TTAPS one-dimensional model! And not one Nobel Prize winner objected!


Blogger Timothy Birdnow said...

Great post! It never ceases to amaze me how people genuflect before the god of ``science`` and will believe anything coming out of the mouth of a ``man of science`` no matter how silly or ill-conceived. Being accomplished in one field does not necessarily qualify you to pontificate on all science. I certainly would not want a nuclear physicist performing an operation on me, no matter how bright the guy is.

Oh, I really like Feynman, too!

5:00 PM  

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