Which term describes the initial freezing action of water?

• A. Slush ice
• B. Frazil ice
• C. Clear ice
• D. Pack ice

Answer: (B)

Frazil ice describes the initial freezing action because it consists of many tiny ice crystals that form directly in turbulent, supercooled water and remain suspended rather than turning into a solid sheet. In cold, moving water, these fine, needle-like crystals appear quickly and create a slushy suspension at the surface. As conditions stay cold, frazil crystals can collide and stick together, eventually developing into larger forms, but the first sign of freezing in such conditions is frazil ice. The other terms refer to later stages or different forms: slush ice is a mix of frazil crystals and water on the surface; clear ice forms from slow freezing that allows drainage to produce a transparent sheet; pack ice describes large, consolidated areas of sea ice.