Jennifer Kosty (Yale University)

October 19, 2025
18:00 local, 70.21◦N, 127.00◦W

Conditions:

• Cloudy
• 0% sea ice cover
• -5^◦C
• Sunrise: 19-Oct-2025 10:02
• Sunset: 19-Oct-2025 18:22
• Day length: 8 hours, 20 minutes

Today, we continued to steam back towards Amundsen Gulf and Cambridge Bay. During the daily science meeting, Andrew Ross gave a fantastic presentation on his work investigating biotoxins in the Arctic Ocean. Biotoxins are toxic substances produced by harmful algal blooms that can cause illness in humans and marine wildlife. Very few studies have investigated biotoxins in the Arctic Ocean, so Andrew and his collaborator Mackenzie Mueller have been working to establish a time series of biotoxin concentrations in the Canada Basin by collecting samples on the past two BGOS/JOIS expeditions. Today, Andrew shared some of their initial findings, which included identifying weak concentrations of biotoxins known to be harmful to fish, shellfish, and marine mammals on the Beaufort Shelf. Afterwards, we adjourned to the mess and enjoyed an excellent lunch of roasted chicken, vegetarian ravioli, roasted root veggies and potatoes, and green peas.

In the afternoon, we were hoping to recover two buoys that had washed ashore nearby by sending a team on the Louis’ helicopter. However, mechanical issues prevented the helicopter from taking off, so the operation unfortunately had to be canceled. But don’t worry, we still have plans to recover these buoys on next year’s expedition! In the meantime, we made the best of the situation by participating in some Arctic tourism! We happened to be close to the Smoking Hills, a series of cliffs in Canada’s Northwest Territories that have been burning continuously for the past few centuries. Underground oil shales, which have sulfur-rich deposits of lignite/brown coal (a combustible sedimentary rock), cause these cliffs to ignite when exposed to oxygen. Captain Briggs maneuvered the Louis close to the coastline, so we had an incredible view of this natural phenomenon. Tonight, we continue our steam home to Cambridge Bay, with an anticipated arrival time around noon on Tuesday.