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To: burzum
What is your point? Are you trying to add credibility to the point that the CO2 in Venus' atmosphere is what has caused the temperature to be that high, contrary to your prior post? If so, good. I agree that the greenhouse effect on Venus is why the temperature of Venus' atmosphere is so high.

No... because I don't think that the CO2 is the cause of the high temperature. It may help maintain it ... a bit.

For the runaway greenhouse effect to take place, the temperature on the planet has to reach first the boiling point of water (100º C) and then the sublimation point (>700º C, I'm told) of the supposed limestone which gets higher and higher as the atmospheric pressure increases. This carbonate and rock sublimation has to occur underground in deep rocks which are excellent insulators.

Perhaps this all happened... but the evidence on Venus has to be looked at in its totality... not based on theories that so far have not been very predictive to real world findings.

14 posted on 10/19/2007 12:44:33 PM PDT by Swordmaker (Remember, the proper pronunciation of IE is "AAAAIIIIIEEEEEEE)
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To: Swordmaker; SunkenCiv
http://www.sciencemag.org/cgi/content/abstract/279/5356/1492

Science 6 March 1998: Vol. 279. no. 5356, pp. 1492 - 1497 DOI: 10.1126/science.279.5356.1492 Prev | Table of Contents | Next

Review

Geological Evolution of Venus: Rises, Plains, Plumes, and Plateaus Roger J. Phillips, * Vicki L. Hansen

Crustal plateaus and volcanic rises, major physiographic features on Venus, both formed over mantle plumes. Crustal plateaus were produced by large degrees of plume melting beneath thin lithosphere. The oldest tectonic features in crustal plateaus are ribbon-like troughs indicating early uplift and tensile stretching; their shallow depths suggest that surface temperature there was higher in the past. Widespread volcanic plains, derived from the broad upwellings of internally heated mantle convection, were continually erupted during the time of crustal plateau formation. Discrete volcanic rises, younger than crustal plateaus, formed over a thicker lithosphere, with less plume partial melting. The presence of only one transitional form indicates that the lithosphere thickened rapidly. Thermal and magmatic models show that the formation of these major features can be tied to an expected change in mantle convective style about 1 billion years ago.

(we can argue about the billion years...later.)

15 posted on 10/19/2007 5:26:10 PM PDT by Fred Nerks (Fair dinkum!)
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