From Pancakes to Pack Ice: The Ross Sea’s Rapid Freeze-Up

When you're a researcher in Antarctica entering the colder months, you're told that the sea ice is going to change rapidly as you approach the Austral winter. You can look at satellite imagery showing the ice form in past seasons - but to witness it firsthand is still surprising!

At the end of February, the sea surface was mostly pancake ice, which is flat, circular plates of ice. Then, as March set in, the ice thickened fast, turning into a solid, stable sheet. This happens as temperatures drop and winds change, but the speed of the transition was still fascinating.

The Antarctic Circumpolar Current (ACC) plays a huge role here. As the world’s strongest ocean current, it influences ice formation by moving cold water and shaping temperature patterns around the continent. For marine life like seals and penguins, thicker ice means more stability. For researchers, it can limit access to sampling sites and complicate fieldwork. Deploying gear and navigating frozen-over areas makes for fluid plans as the expert crew navigate in the Ross Sea. Watching this shift reminds me how much the environment controls what we can study and how we do it.

Even with the ice thickening, we've been very lucky to have 18 successful EBS deployments and to have collected over 6,000 cumaceans!

Victoria Vandersommen
University of Alaska Anchorage