On the coagulated pancake ice formation: Observation in the refreezing Chukchi Sea and comparison to the Antarctic consolidated pancake ice

Abstract

Emergence of pancake ice in the western Arctic Ocean is understood to be an effect of the increasing wave activity. During the 2018 R/V Mirai field campaign in the refreezing Chukchi Sea, we obtained observational evidence of sea ice formation that resembled the pancake cycle—frazil/pancake/consolidated pancake ice—first discovered and known to be ubiquitous in the Antarctic. Apparently, R/V Mirai encountered a sequence of environmental conditions that were conducive to producing coagulated pancake ice, of which the formation process was relatable to the Antarctic consolidated pancake ice. We investigate how pancake ice form in two different environments: the Antarctic marginal ice zone (MIZ) is adjacent to the vigorous Antarctic Circumpolar region whereas the western Arctic Ocean is surrounded by sea ice and land. We found that a key distinction between the two regimes is that rafting is less likely in the western Arctic Ocean due to its wave climate, meaning the coagulated pancake ice is thinner than the Antarctic consolidated pancake ice. As the sea ice extent declines, thinner coagulated pancake ice may dominate the refreezing ocean, which affects the melting and possibly the broader Arctic climate.