Raerakenteen

Raerakenteen is a Finnish term that translates to "ice crystal structure" or "hailstone structure." It refers to the internal arrangement of ice particles within a hailstorm. Hailstones are formed in cumulonimbus clouds through a process of repeated updrafts and downdrafts, accumulating layers of ice. The specific patterns and textures of these ice layers, such as the presence of clear or opaque ice, contribute to the overall raerakenteen.

The formation of different types of ice within a hailstone is influenced by factors like the temperature of the cloud, the amount of supercooled water available, and the speed of the hailstone's ascent and descent. Opaque ice, often appearing milky or white, forms when air bubbles are trapped within the rapidly freezing water. Clear ice, which is denser and more transparent, forms when water freezes more slowly, allowing air bubbles to escape. The alternation of these ice types can create distinct growth layers within a hailstone, observable when it is cut open. Studying the raerakenteen of hailstones can provide insights into the meteorological conditions within the parent thunderstorm. This can include information about updraft speeds and the presence of varying amounts of liquid water at different altitudes. Analyzing these structures is a method used by meteorologists to better understand hail formation processes.