"I’m still searching:
for anyone (or any place) that has information on how much radioactive material is in the atmosphere these days."
Don't know, but considering how much of it that occurs "naturally" I would say near the average amount that's "always" been in the atmosphere.

If I understand you correctly, in your opinion, the radioactive 'leaks' from nuclear power plants and the detonations of nuclear devices in the atmosphere and near space have not had any effect what so ever on the atmospheric condition of the Earth, yet the amount of hair spray material and the gas that the animals 'expel' has had an effect.
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"Also I’m interested in knowing if anyone has made the connection that radioactivity in the atmosphere may be ‘heating’ (imparting kinetic energy to) the atmospheric molecules."
I'm sure it produces some heat, but it would be utterly insignificant compared with other factors (like sunlight).

I agree with you that the sun is the major contributor of energy to the Earth. I also agree that the Earth's internal heat can contribute to the energy balance. (Also to life in some parts of the oceans.) But it still would be interesting to know how much 'extra' energy has been introduced to the atmospheric environment by the 'disbursement' of nuclear activity into the atmosphere.
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"Then furthering that thought, I’m interested in knowing how fast the atmospheric molecules are moving in the ‘thermosphere’ and above it."
Fast. I believe temperature is over 2000 F.

Wow !! I wonder if the molecules move faster than seven miles per second
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"I know that any object that has the velocity of seven miles per second can escape the Earth’s gravitational influence."
Assuming this object doesn't collide with another object.

As I understand it there are less objects in the upper parts of the atmosphere for the speeding molecules or ions to collide with.
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"I also know that radioactive decay of atomic nuclei imparts kinetic energy to the surrounding atomic elements; besides causing the surrounding elements to become radioactive."
Just, to clarify- radioactive material doesn't "grow" more radioactive material- a given quantity X radioactive material decays over time- over time less material becomes radioactive- otherwise our energy problems would be solved:)

I do not fully understand 'breeder' reactor operation or the reason why the reactor 'fuel' is more radioactive after it has been in the reactor. Could you explain it please.
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"It has been proposed on this board that the Earth’s magnetic field will somehow prevent energetic particles from escaping the gravitational field of the planet."
No, you probably got this backward. Earth doesn't emit significant quantities of high energetic particles- the Sun and exploding stellar objects are source of these particles. The Earth's magnetic field deflects most of these particles from entering Earth atmosphere- the magnetic field also traps these particles (Van Allen Belts).

Under 'normal' circumstances your explanation is correct. I am only pointing out that the introduction of radioactivity has most likely changed that equation, simply because the fission material in the atmosphere would have high energy particles associated with it. What is the amount of this 'insignificant' quantity of energetic particles that are escaping into space?
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"The implication seems to be that radiation, man made or natural, including the VanAllen belt has no accelerating influence on the activity of air molecules."
Aaah.
Van Allen belt start at about 1000 miles up- beyond Earth atmosphere which "ends" around 600 miles (or could be km, not sure).

You can find that and other interesting facts on this site.
best of traditional

And radiation man made or otherwise shouldn't have any significant affect on accelerating air molecules.

On what fact do you base this premise?
Of course I should have called the ‘particles’ in the upper atmosphere by other names such as, ions, protons, alpha, beta, electrons or something else. The point is that they are still part of the ‘atmosphere’. They may also have some type of a ‘coupling’ effect on the neutral ‘air molecules’ at lower levels.
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"I’d like to know the basis of the conjecture that magnetic fields can prevent energetic particles from moving faster than seven miles per second."
They don't stop, they bend the path of high energy particles- and the speed can be much higher than 7 miles per sec- some approach the speed of light.

I will agree with that. The speed of the particles that are emitted from the splitting nuclei of radioactive material also have similar velocities. Yet you claim that they have no influence on the surrounding material.
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"As I understand it, the Sun has a greater escape velocity than Earth and there are magnetic fields associated with the Sun, yet it is able to expel massive quantities of energetic particles into space . Why could this not happen on Earth?"
It could (see above- Earth isn't a source of high energy particles)

I thought that nuclear fission ‘DID’ contain high energy particles.

"So far I have found many interesting and informative web sites; non of which give the information that I need."
Try this:
http://helios.gsfc.nasa.gov/cosmic.html
or go to Google and search "cosmic rays"
http://directory.google.com/

Thank you for the links and the opportunity to ‘argue’ with you about matters that intrigue me.