An Arctic Expedition
Jingxuan Li, IsoSiM MSc student in Oceanography, UBC
Thanks to the support from the IsoSiM programme and my supervisor Dr. Maite Maldonado, I was able to participate in a research cruise in the Arctic from July to October. The 2015 GEOTRACES expedition aboard the Canadian icebreaker the CCGS Amundsen sailed from Quebec City through the Canadian Arctic Archipelago, where the environment responds rapidly to climate change. The cruise is Canada’s contribution to the international GEOTRACES program, which aims to identify processes and quantify fluxes that control the distributions of key trace elements and isotopes in the ocean, and to establish the sensitivity of these distributions to changing environmental conditions.
During the three months, there were scientists from approximately 20 institutions doing research including marine production, ocean acidification, mammals, etc.. My job had two aspects. One was the investigation of particulate (ϕ>0.45 μm) trace metal contents in the Arctic Ocean, which required seawater collection and filtration afterwards on board. The other was the measurement of iron uptake of phytoplankton, using 55Fe as an isotopic spike. Just like the bucket effect, iron is considered to limit production in 30% of the global ocean, thus lowering the capacity of the ocean in taking up CO2 from the atmosphere. Therefore, it is strongly important to learn the iron uptake process and ability of phytoplankton, a unicellular marine algae which dominants marine photosynthesis, in different environments (low Fe/high Fe). We made an iron solution with a known ratio of radioactive 55Fe to non-radioactive Fe and added it into the media where cells stayed, and the phytoplankton took iron according to the ratio. By measuring intracellular radioactivity periodically, we could calculate the total iron uptake.
Life on board was tiring and demanding, as the ship could hit a station anytime, which sometimes meant working all night and breaking body clock. This difficulty was amplified by the perpetual daylight, which gave people a hard time falling asleep, although they were exhausted. Stressful work, shortness of fresh vegetables, and seasickness were experienced by everyone, but for sure were compensated by the beautiful sunset/rise, the Aurora Borealis, and polar bears. Luckily, I was sharing a room with my best friend. We used to be in the same undergraduate programme in China and were both enrolled in Canadian graduate schools. Also, an episode was inserted to the original plan. Our icebreaker was called to escort resupply ships in Hudson Bay, as an unpredicted heavy ice condition prevented the ships from reaching northern communities in time. Science was ceased for 11 days and scientists were frustrated because they had been preparing for the cruise for months or years, in labs, offices or 24-hour cafeterias across Canada.
There is a blog telling more detailed stories about the cruise, updated by our lab. Interviews of scientists, nice pictures of the Arctic and essays talking about feeling about expeditions can be found.