Re: Dose Correlation (rads to watts per second) -Geological sciences link

["David Krueger" <dkrueger@icnpharm.com>]

Stewart Farber wrote:
I may be wrong, but it seems to me that the major factor in making the
earth a
habitable planet is it's ability to sustain an atmosphere with enough
carbon
dioxide to make the greenhouse effect maintain temperatures within narrow
bounds such that life can exist, not the decay heat of radionuclides within
the earth. Without the greenhouse effect at work within tight bounds [due
mainly to the earth being of a certain size, with a certain gravitational
field, able to hold its evolving atmosphere in place] the temperature
balance
of the earth after receiving its share of solar radiation would lead to too
much heat loss with heat being radiated back to deep space [and frigid
temperatures unable to support life], or too much heat being retained with
temperatures too high to support life as well.

The carbon dioxide levels in the atmosphere are regulated by various
feedback loops between the atmosphere and terrestrial and aquatic biosphere
which has
become part of the Gaia hypothesis and which is presently the subject of
expanding interdisciplinary research.

My comment is that the radionuclide-generated heat that drives Plate
Tectonics makes the stable carbon cycle possible. If sequestered carbonates
on the ocean floors were not driven to great depths through subduction, the
emission of CO2 via volcanoes would not occur; CO2 would have been emitted
only when earth was young, deposited in deep ocean basins and then remained
there for all time. Even given the earth's size, gravity, etc., without the
internal heat of radionuclides, the earth would have become "dead" from a
geologically/biological perspective, as have Venus and Mars. So the "good"
greenhouse effect and radionuclide heat are related.

These are the opinions of someone who watches too much of the Discovery
Channel.

David Krueger
dkrueger@icnpharm.com
714-545-0100


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