MOSAiC: An inside look at the largest Arctic expedition in history

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.

The Russian icebreaker Kapitan Dranitsyn alongside the Polarstern during the wintertime in the central Arctic Ocean. Photo: Esther Horvath.

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!

Home sweet home! Extra accommodation was needed on the Maria S Merian so many of us slept in converted containers chained to the deck. Photo: Jessie Gardner.

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.

Team ECO during Leg 4 of MOSAiC. Left to right: Celia Gelfman, Allison Fong, Jessie Gardner, Giulia Castellani, Oliver Müller, John Paul Balmonte and Katyanne Shoemaker. Photo: Lianna Nixon.

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.

Participants from 70 institutions in 20 different countries took part in the field campaign where everyone worked towards a common goal. Photo: Jessie Gardner.

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.

On its return in October 2020 the Polarstern offloaded thousands of samples which are being shipped around the world for further analysis. Photo: Jessie Gardner.

 

Searching the Arctic ocean for novel antimicrobials – our first research cruise experience

Written by Andrea Iselin Elvheim and Ataur Rahman.

Sea ice.

In august we attended a research cruise on the research vessel “Kronprins Haakon”, the Biodiscovery Cruise 2020. We were three scientists from our group: The Marine Bioprospecting Group, together with 14 other scientists mainly from UiT. The aim of our group was collecting marine invertebrates, marine sediments, and marine bacteria for discovering bioactive compounds. The discovery of novel bioactive compounds is important in combating the increasing amount of antimicrobial resistance in bacteria and finding new medicines. New compounds can also be useful in research and other industries.

The participants from the Marine Bioprospecting Group: Ataur Rahman, Klara Stensvåg and Andrea Iselin Elvheim, on Bear Island.

We started in Longyearbyen 4th of August and travelled north towards the ice edge. Our first sample was from the northernmost part of the cruise. Then, we sampled while moving south along the Atlantic Ridge. A major highlight was sampling from the Molloy Hole, the deepest part of the Arctic Ocean, with approximately 5550 m below the surface. With the help of the experienced crew, we finally succeeded in collecting sediments after three unsuccessful tries. We also sampled around and on Bear Island, before we travelled back home to Tromsø on 22nd of August.”

The stations where we collected samples.

In the northernmost parts of our journey, we got to experience large amounts of drift ice, a truly fascinating sight. After a week of nice weather and almost completely calm waters, we encountered the rough, undulating sea and experienced seasickness for the first time. That cost us one day of working! We went ashore on Bear Island, on a beautiful beach below a bird cliff with unfathomable amounts of birds. There were several species of birds including fulmars, seagulls and puffins. After the final sampling near Bjørnøya, we had the chance to catch some fish. We enjoyed sorting the fish, learning how to cut filets, and got to taste some fresh shrimps on board.

Puffins on Bear Island. Foto: Aleksander Eeg.

Life on board followed specific routines. It revolved around meals and collecting samples, in that order. We were sampling continuously through the day and night, and therefore had to work in shifts. Between the meals, our shifts, and when waiting for samples we had some spare time. This was mainly spent socialising, sleeping, reading, watching movies, exercising, knitting, or watching whales and birds. Parts of the journey, a young falcon accompanied us, after he lost his course and got stranded on the ship. He soon won everyone’s hearts and became the mascot of the cruise.

The falcon visiting RV Kronprins Haakon during the cruise. Foto: Aleksander Eeg.

For our group the sampling mainly consisted of isolating bacteria from marine invertebrates and marine sediment. We collected marine invertebrates, such as sponges, sea stars, sea anemones, and bryozoans from the bottom of the sea using a beam trawl, a small trawl that moves along the bottom. First, we rinsed the contents of the beam trawl were of sediments. Then, we sorted the animals. We crushed interesting invertebrates with sterile salt water, and plated this on agar plates. To collect sediments we used a box corer, a box with a lid for the bottom that closes after the box has been pressed into the sediments. The sediments are trapped in the box exactly as they were on the seabed. After collecting sediments we mixed it with sterile salt water and plated it on agar plates. In addition to growing bacteria, we also froze down big quantities of animals for chemical extraction of compounds.

The marine invertebrates we collected from the Molloy Hole.

Taking sediment sample from the box corer.

Now that we are back in Tromsø, we will continue with isolation, identification and characterization of interesting marine bacteria that could be a potential source of bioactive compounds. We are excited about getting some new equipment that will help with identifying bacteria, and we are optimistic that we will get some good results. For the two of us, this was our first research cruise. We had many new and amazing experiences, got to know some new people, and hopefully we will get some interesting results, helping us towards finishing our PhDs.

Bacteria from one of the marine invertebrates.