Ice caves are found in Eastern Oregon, Idaho, Pennsylvania, Iowa, and in other states. The caves are very long and narrow and have relatively small openings. Long, cold winters seem to be an essential also in most of them. The cold, heavy air fills the caves, and condenses the warmer, moist air below the freezing point, forming ice as the two diffuse slowly at the entrance. If the air chamber is large enough and the cave opening small enough, the diffusion and ice-forming will continue throughout the year, as in the cave in Bixby State Park. If not there will be an ice-free period as in the ice-cave near Decorah.
Proceedings of the Iowa Academy of Science
©1932 Iowa Academy of Science, Inc.
Smith, John E.
Proceedings of the Iowa Academy of Science, 39(1), 196-196.
Available at: https://scholarworks.uni.edu/pias/vol39/iss1/48