Written by postdoctoral fellow Jessie Gardner, AMB.
MOSAiC was the largest ever expedition to the Arctic, with one purpose: to improve our understanding of climate change.Dr Jessie Gardner, from the Department of Arctic and Marine Biology (UiT), was on board during the summer and shares her insights from this exceptional scientific campaign.
Unravelling the mysteries of the Central Arctic Ocean
In 2019 the German research icebreaker, Polarstern, set sail from Tromsø bound for the Central Arctic Ocean, the epicentre of climate change. Once there, the ship allowed itself to become trapped in the ice for a year, drifting alongside an ice floe with the speed and direction of the winds and currents alone. The idea follows that of the Norwegian researcher and explorer Fridtjof Nansen, who set sail on the first ever drift expedition with his wooden sailing ship Fram 127 years ago. The Polarstern was laden with state-of-the-art scientific equipment. Throughout the year, 442 experts from 70 institutions in 20 different countries took part in the field campaign, which was supported by six other ships, several aircraft and hundreds of others on land.
The Polarstern reached the northern Laptev Sea by mid-October 2019, located a suitable ice floe and set up a small floating city of scientific instruments in time for the polar night. With temperatures plummeting to -42°C and fierce winds transforming the ice around them, researchers battled to sample the floe in the darkness. Ultimately, they succeeded, giving us a rare glimpse into the central Arctic Ocean environment during the winter while the sea ice thickened beneath their feet.
Research expeditions into the central Arctic Ocean have traditionally be fraught with problems and MOSAiC was no exception. Some of them were predictable and had been considered during the decade of planning, such as the Russian icebreaker Kapitan Dranitsyn being much delayed by the strength of the winter ice pack. Other issues were completely unforeseen, like the declaration of a pandemic around the world- just as the spring rotation of participants, crew and re-supplies was planned.
It was this rotation that I was scheduled to be part of part of “Team ECO” and the HAVOC project (Ridges – Safe HAVens for ice-associated Flora and Fauna in a Seasonally ice-covered Arctic Ocean). HAVOC is the largest Norwegian project to participate in MOSAiC, led by the Norwegian Polar Institute and funded by the Research Council of Norway. HAVOC aims to investigate sea ice ridges and their role in the Arctic sea-ice system. However, there were moments where it seemed like the MOSAiC field campaign might have been abandoned completely…
How to continue research during a global pandemic
The first hint of the seriousness of coronavirus came after I had attended a polar bear protection training course at the beginning of March in Germany. We were all tested for corona as a precaution, and one of the participants tested positive! I received the news while making a pit stop in the U.K. and immediately went into 2 weeks of quarantine. During those 2 weeks, coronavirus shifted from being a distant issue to a severe threat around the world. Straight after, countries went into lockdown, borders closed and plans for the Spring personnel exchange from Svalbard to the Polarstern were abandoned.
The MOSAiC coordinators, led by the Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research (AWI), worked tirelessly to find an alternative despite airports, military facilities and seaports worldwide shutting down. First, we gained special permission to travel to Germany, underwent testing and then quarantined in isolation for two weeks. After I boarded the research vessel Maria S Merian and spent another two weeks sailing to Svalbard, sleeping in a modified container chained to her deck. The Polarstern had to leave the camp and floe temporarily for the personnel exchange. Unfortunately, this was at the cost of capturing the crucial time when the ice begins to melt, but this is a small price to pay compared to abandoning the expedition altogether.
I could hardly believe it when we finally reached the floe. Photos of sea ice from above makes it seem like a vast expanse of white, flat nothingness but actually this landscape is a diverse and beautiful- littered with tall ice blocks, jagged ridges, leads, cracks and melt ponds which change before your eyes. Now, we could finally get stuck into the science!
Going with the “floe”
Team ECO collected thousands of samples and measured a diverse suite of ecological and biogeochemical properties from snow, ice, and seawater. With the Polarstern as our base, we built onto the time series capturing the variability of the Arctic system. The dynamic nature of the Arctic and how fast the world around you can transform was something that really struck me. There were new cracks opening and closing throughout the floe, as well as melt ponds and streams forming and draining which we would have to jump over or wade through on the way to collect the samples. These events would be accompanied with a cascade of processes and pulses of life within the associated ecosystem. We were only able to capture these through intensive sampling bouts, working on the ice for 24 hours straight, powered by copious amounts of coffee and gummy bears.
You had to be constantly vigilant, since below us was thousands of meters of seawater, and a polar bear could emerge from the sea ice rubble any time! We were lucky during our time on the floe in that we experienced long periods of calm weather with perpetual bright sunshine. Occasionally there were some very foggy days where it was too unsafe to work on the ice due to poor visibility hindering polar bear guarding.
Breaking boundaries: working together for a common goal
The name MOSAiC (Multidisciplinary drifting Observatory for the Study of Arctic Climate) reflects the complexity and diversity of the science during the expedition. The MOSAiC field campaign provided an unparalleled opportunity to simultaneously observe and measure the temporal evolution of a number of co-varying Arctic climate system variables from the central Arctic atmosphere, ocean, and ice. With this mindset I was amazed how much more we were able to achieve by working together. For example, it would have been impossible to have collected the number of samples for the HAVOC project that we managed, without others volunteering their precious free time to help. Working across these disciplines and breaking down the boundaries between traditional subjects will give new perspectives on the central Arctic, and it is here that ground-breaking discoveries could be made.
The expedition has ended, but the research is only just beginning
While the field campaign has ended, MOSAiC is by no means over. Samples are now being shipped to various institutions around the world to be analysed. These, alongside the suite of measurements taken by other teams will likely take the scientific community over a decade to analyse the data collected on MOSAiC. Through virtual meetings we have kept the cross-cutting discussions alive and we already have ideas of combining data and theories in unique and exciting ways. These data and observations will be fundamental to improve our understanding of climate change, and help inform pressing political decisions on climate protection.