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To cut down on the tedium and repetition of the same old same old, I will not break down Pale's two posts paragraph by paragraph and comment on each, but I will summarize and comment here knowing that Pale will correct me if I mischaracterize anything.

 

Pale continues to claim that researchers altered the original raw data and further, NASA's James Hansen comes up with erroneous results. Pale then scoffs at climate scientists in general. Nothing new here.

 

He claims that I hold my views on modeling for political reasons and later claims I lack scientific background.

 

He doesn't like my analogies where I try to address the concepts of modeling in other fields where it is analogous to the modeling in warming. He disparages my analogies as erroneous thinking. I suppose that's true in a way, but analogies are a good learning tool. Many Nobel prize winning scientists made their discoveries through unrelated analogies, in chemistry and physics.

 

He goes on to claim that flat earth with no rotation is inappropriate for making graphs of temperature, but never said how he would use rotation specifically on historic temperature measurements that are scalar and not vector.

 

In his second post, he bitterly presses his claim on fabricated data. Nothing new here.

 

As per Pale's request, lets switch to his completely different topic: how greenhouse gasses can cause warming on the earth. Here the rotation of the earth does become important, and creates a very complex energy exchange system.

 

At any specific point in time large parts of the earth are in these broad categories:

1. A winter climate at night, (Say Maine)

2. A summer climate at night (Say New Zealand)

3. A winter climate in daylight

4. A summer climate in daylight.

As the hours and seasons progress, the boundaries of these areas continually change.

 

At times and places, the atmosphere is colder than the nearby ground, and at times it's not. The majority of energy exchange is convection (like wind.) For the radiation fraction (10%?), the second law of thermodynamics comes into play. I will express radiant energy flow and the 2nd law in a way that may be surprising to some not well versed in the sciences.

 

1. Radiant energy flows from a cold body to a hot body.

2. Simultaneously radiant energy flows from the hot body to the cold body.

3. The net energy flow is always from the hot body to the cold body. (2nd law)

 

Many people forget about #1.

 

As Pale says, the greenhouse gasses cause certain long wavelengths (IR) to reradiate energy in all directions. The majority of this IR is backscattered to outer space and very little reaches the earth - a cooling effect.

 

Wavelengths from the sun outside those absorption bands do hit the earth. Some of it is absorbed and heats the earth and nearby air. The heated earth reradiates IR energy. The earth is way too cold to reradiate short wavelengths, (except from light bulbs, or steel foundries.) Where does this reradiated IR energy go? Some of the IR energy radiates back to space, but a significant part of earth's radiant energy is backscattered to earth by the same physics that the sun's IR energy was backscattered to space. In short, the greenhouse gases trap some radiant energy.

 

The next question is how can the trapped radiant energy be absorbed by the earth in those places where the earth is warmer than the atmosphere.

 

The answer lies in my statement #1 above. In this case, the warm earth is radiating lots of IR which is absorbed by the cold atmosphere, and the cold atmosphere is radiating lots of IR in the greenhouse bands back to be absorbed by the earth. (Let IR in the green house bands be called GH-IR.) Of course the direction of the net energy flow of all bands of IR radiation and convection is from the warm earth to the colder atmosphere (2nd law). The backscattered component of the GH-IR absorbed by the earth is the mechanism by which the earth gains some thermal energy from the GH-IR radiant energy even though the earth is warmer. But, by the 2nd, law the net result is that the atmosphere near the warm earth would heat up and continue to backscatter GR-IR to the earth while the earth continues to radiate more IR energy to be backscattered.

 

What happens if the atmospheric CO2 were doubled? It affects two directions: the sun's GH-IR will be backscattered to space as usual and still very little of it will hit the earth. So there's not much change in energy from the sun. However some IR from the earth will be further trapped by a doubling of backscattering of the CO2 portion near the earth and cause an increase in warming via my statement #1.

 

A final question is, why is the IR energy flow so much larger than the solar input as shown in the wiki greenhouse article? Pale has the answer in his analogy of a heater in an insulated box. The sun's fuel source is like the power cord going to the heater. The heater energy is trapped in the box and grows larger and larger over time. Very soon the trapped radiant energy circulating in the box will become a dominant source of radiant energy in the box.

 

There are further considerations such as a bit of CO2 heating allows the atmosphere to hold even more water vapor which is the predominant green house gas. Water vapor has a fast source and sink of water, but CO2 and CH4 don't. This post is already too long to go into all that now.


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