From: George Murphy
Use of "unknown physics" can be either either an appeal for phenomena &/or
laws which go beyond presently established physics OR vague & generally qualitative
claims (what back in grad school we called "handwaving") that somehow when all the
complicated phenomena are taken into account things will work out the way you want them
to. The second use is most effective when you know beforehand the answer you want to
get - like the answer in the back of the book or a global flood. & this second type of
argument is what you've given in response to the detailed studies of an asteroid impact
which Glenn cited.
AR: Let's take the second point first. From the Creationary Catastorphist point of view it is a Fact from witness evidence that a Flood happened. The natural world is then scientifically studied within that viewpoint to determine what happened (not to prove that it happened, which would be circular reasoning).
Evolutionists do the same thing. The Natualistic paradigm denies anything other than matter/energy and so Abiogenisis is a fact becuse life is here and could not have gotten here by any other way. Actualism is a fact because there is nothing which can willfully disturb the natural order of things. Geologic evidence is interpreted within the facts of Actualism and Abiogenesis. The fossil record then becomes the record of genetic variation over time. And so, Evolution is a fact, extrapolted from the fact of genetic variation and the fossil record. The natural world is then scientifically studied within that viewpoint to determine what has happened. (hopefully no one attempts to prove evolution, because that is already assumed.)
Take just the first of your arguments, that redistribution of CO2 & H20 in the
atmosphere would change the absorption of the earth's thermal radiation. As a first
approximation take a simple model in which N molecules are distributed uniformly in an
layer of atmosphere of height h << R, where R is the radius of the earth. The number of
molecules per unit volume is then n = N/(4*pi*h*R^2). If the cross section for a
particular scattering process by a molecule of a photon of a certain energy is s, the
mean free path of a photon is L = 1/ns = (4*pi*h*R^2)/Ns, which is proportional to h.
Thus h/L, the average number of times a photon would be scattered in passing through the
layer of moecules, is independent of the thickness of the layer. Or to put it another
way, the probability of scattering doesn't depend on the thickness.
This is a very crude calculation with a crude model, but it does suggest that
the effect you appeal to wouldn't make a significant difference. If you disagree,
present a more refined model & calculations based on it to support your position.
AR: The complete equation for n should be:
n=N/((4*pi*h*R^2) + (4*pi*R*h^2) + (4/3*pi*h^3))
Because of the several orders of magnitude difference between R and h the first term containing R^2 is the dominant term. However, the other terms do show that there is an actual reduction in the scattering, though it is small (on the order of 1/1000 and less than the dominant term.) So George is correct that expanding the height makes only a small difference.
I need to modify my original statment to read:
> The distinction between
> Troposphere, Stratosphere and Mesosphere, etc. become no
> more (assuming that that was the same structure before hand)
> for a while. H2O and CO2 are primarily concentrated in the
> Troposphere. The mixing of the Troposphere with the rest of
> the atmosphere would ... allow
> for greater radiation.The lack of Tropopause, Stratopause,
> etc would result in much higher rise of warm air (closer to
> space) and result in greater facility to heat loss.
Finally, let's step back and look at the big picture. It seems to be agreed
that a single large asteroid impact would have a number of catastrophic effects on
terrestrial life. It would be a bit surprising, to say the least, if a lot of
near-simultaneous impacts had a _less_ catastrophic effect.
To be sure the greater number of impacts, the more catastrophic the effect. There would indeed be a larger input of energy into the system than a single impact, however, multiple impact would do something which a single impact could not do. A large portion (if not all) of the atmosphere (which is has the major effect on longwave radiation from the plant) would be disturbed. The larger the disturbance the great the amount of heat loss.
Any estimate of energy input from multiple must be tempered by the greater amount of heat loss due to the highly disturbed atmosphere. Estimates based on a single impact must be modified to account for different atmospheric conditions from multiple impacts.
Allen
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