Frazil Ice in the Antarctic Marginal Ice Zone

Frazil ice, consisting of loose disc-shaped ice crystals, is the first ice that forms in the annual cycle in the marginal ice zone (MIZ) of the Antarctic. A sufficient number of frazil ice crystals form the surface grease ice layer, playing a fundamental role in the freezing processes in the MIZ. As soon as the ocean waves are sufficiently damped by a frazil ice cover, a closed ice cover can form. In this article, we investigate the rheological properties of frazil ice, which has a crucial influence on the growth of sea ice in the MIZ. An in situ test setup for measuring temperature and rheological properties was developed. Frazil ice shows shear thinning flow behavior. The presented measurements enable real-data-founded modelling of the annual ice cycle in the MIZ.

Automated summary

Frazil ice, the first ice forming in the annual cycle in the Marginal Ice Zone (MIZ) of the Antarctic, consists of loose disc-shaped ice crystals and plays a fundamental role in the freezing processes by forming the surface grease ice layer. The rheological properties of frazil ice, including shear thinning flow behavior, have a crucial influence on the growth of sea ice in the MIZ, and real-data-founded measurements enable modeling of the annual ice cycle.