Dispatch 17: Shrinky cups
Jennifer Kosty (Yale University)
October 4, 2026
12:30 local, 78.17◦N, 153.16◦W
Conditions:
- Flurries
- 100% sea ice cover
- -6.3◦C
- Sunrise: 10:13 PDT (local)
- Sunset: 19:46 PDT (local)
- Day length: 9 hours, 33 minutes
It’s time for everyone’s favorite rosette cast of the cruise – the shrinky cup cast! Shrinky cups are a beloved, long-standing tradition on the annual BGOS/JOIS cruises. Everyone on board is invited to decorate a foam cup. The cups are then collected in a mesh bag, attached to the rosette wire, and sent to the bottom of the Arctic Ocean. The weight of nearly 4000 m of water above compresses the cups, causing them to shrink to roughly 45% of their original size! These cups make great souvenirs and gifts for friends and family. Many were decorated with polar bears, seals, northern lights, and the Louis. There were also plenty of non-Arctic related cups. For example, I made a shrinky cup for one of my friends featuring her cats, Gorgonzola and Pistachio. The cups were shrunk during yesterday’s cast at CB11. Afterwards, we were all excited to collect our tiny souvenirs!
Now that we have officially wrapped up our ice operations, today’s focus shifted back to rosette work. The night watch completed a 2200 m cast at CB10 around 9 am. Our journey to CB10 took slightly longer than expected given the ice conditions. We were transiting through a patchwork of thick, multiyear ice and thinner, newly forming ice. Many of us were awoken in the night by thunderous crunching noises as the Louis rammed into thicker ice chunks. Thankfully, our bridge team was still able to navigate us safely to CB10 by first light.
During the cast at CB10, we observed a few issues with the rosette wire block, which controls the speed at which the rosette is lowered through the water column. After the cast, watch leader Chris Clarke and co-chief scientist Paul Macoun disassembled the block and worked to find a solution. Problem solving on the Louis often requires some creativity given our limited resources, but we are confident that we will have the rosette up and running again soon!
