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Loren Booda
Aug28-03, 05:42 PM
Dry ice forms at -109.6oF. The record low natural temperature measured on Earth (Antarctica) was approximately -129oF.

Does the solidification of carbon dioxide mediate temperature there, either by heat of sublimation or reduction of greenhouse effect?

Would long-term global climate be critically affected by such a phase change?

marcus
Aug28-03, 06:17 PM
Originally posted by Loren Booda
Dry ice forms at -109.6oF. The record low natural temperature measured on Earth (Antarctica) was approximately -129oF.

Does the solidification of carbon dioxide mediate temperature there, either by heat of sublimation or reduction of greenhouse effect?

Would long-term global climate be critically affected by such a phase change?

Loren I imagine that dry ice forms at that temperature
in CO2 of one atmosphere pressure

but the (partial) pressure of CO2 in our atmosphere is only
on the order of a percent of that----i forget exactly, some fraction of a percent

so the CO2 in our atmosphere is not really at one atmosphere pressure
and I doubt it could form dry ice at the temp you indicate

there are some table is the CRC Handb. of Chem and Physics about the vaporpressure of dry ice at various temps that might allow one to figure out

I didnt look up anything so cant speak with assurance but i do believe the partial pressure matters