The Formation of Ice Crystals

When pure liquid water suspended in the air is cooled, it keeps the liquid state till about −35C. Liquid water at temperatures below the freezing point is called supercooled water. The supercooled water is transformed spontaneously into ice at about −35C. The rate of freezing is determined by the rate at which the latent heat liberated by freezing is removed. In the case of freezing of the water supercooled to s degrees centigrade, s /80 parts of the volume are transformed instantaneously into ice at the moment when freezing starts, because the latent heat liberated is 80 cal g −1 . The whole system, s /80 parts of ice plus (1− s /80) parts of water, is warmed up to 0C, and the speed of later freezing is a function of the rate of removal of the latent heat liberated by the subsequent freezing. Altberg [1] studied the freezing of the rapids in Siberia, and found that most of them are supercooled to the order of −0.05C just before freezing commences. These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.