What is supercooled water?

Supercooled water refers to liquid water that remains in a liquid state even when its temperature falls below the normal freezing point of 0 degrees Celsius. In the context of the phases of water, supercooled water can exist at temperatures significantly below freezing, often down to about -40 degrees Celsius without transitioning into ice. This phenomenon occurs because the water molecules have not yet found a substrate or a nucleation site to begin the freezing process, allowing them to remain liquid under these conditions.

This behavior is significant in atmospheric science, particularly in the formation of ice in clouds and precipitation processes, where supercooled droplets can exist and interact with particles, leading to phenomena such as freezing rain. Understanding supercooled water helps explain various weather phenomena and the behavior of water at low temperatures.