|MadSci Network: Physics|
Hi Frank, Frozen CO2 has been observed on other planets and that would indicate that CO2 would freeze on our planet when the temperature dropped below the freezing point of gaseous CO2. Although I've not read any references to observations of frozen CO2 at our poles, I would believe the possibility. Since the concentration of CO2 in our atmosphere runs around 0.03 to 0.06%, it would have to remain very cold for a very long period to accumulate frozen CO2.
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