frost flower

A striking flower-shaped hoarfrost structure that forms on a layer of sea ice (pack ice) under certain environmental conditions. The phenomenon has its origin in the water vapor that manages to escape through the small cracks and gaps present on the frozen surface. If the air in contact with it is very cold - at temperatures near –22°C - and calm, sublimation of the water vapor takes place, and the flower develops. The salt particles present on that floating layer of ice act as freezing nuclei, supporting the frost crystals making up the beautiful structure. The roughness displayed by the pack ice also contributes to this. One of the peculiarities of frost flowers is that they are salty, something that does not occur with ice formed by the direct freezing of seawater. Frost flowers do not appear alone, but forming meadows that reach a considerable extent. They are documented both in the Arctic and in Antarctica and also on the frozen surface of some freshwater lakes and lagoons.