MOSAiC School – The Importance of Being the Support

Thea Schneider has been supported by the WMO Polar Prediction Project to join the MOSAiC School. About twenty early career scientists were able to take part in the unique floating school aboard the Russian research icebreaker Akademik Fedorov. For six weeks, in September and October 2019, Akademik Fedorov supported RV Polarstern, the German research icebreaker, on her transit into the central Arctic sea ice. A very personal report from the MOSAiC School participant Thea Schneider currently finishing her Master in Physics at the University of Potsdam, Germany. 

Getting Ready for the Arctic: the “Dry Days”

My journey began in Tromsø, Norway, where I arrived a couple of days before boarding the Russian research icebreaker Akademik Fedorov, to attend the so-called “Dry Days” of the MOSAiC School.

Kick-off was a warm welcoming icebreaker party at the campsite, where early career scientists were accommodated in cabins to get to know each other. Here, I also first met the MOSAiC School organizing team: Josefine Lenz from AWI Potsdam and Thomas Rackow from AWI Bremerhaven.

The Dry Days were filled with safety training, lectures and presentations, including an introduction to MOSAiC by project manager Anja Sommerfeld and expedition leader Markus Rex. Challenges and expectations were discussed regarding the near future: living for six weeks in a very confined space with a lot of people and almost no communication to the outside world, right in the middle of the Arctic. We had quite some worries, but it turned out that, if you have great people around and a positive mood on board, alone time and personal space is only needed to a very limited extent.

The Dry Days lecture I personally liked the most was on “Social ecological systems of the Arctic Yakutia in the context of global change”, given by the Yakutian geographer Stanislav Ksenofontov. While it is easy for natural scientists like me to just focus on climate change, it is crucial to also think about the impact of climate change on indigenous communities.

Phase 1 – Navigating the Arctic Towards a New Home

Phase 1 of the MOSAiC School was the transit aboard Akademik Fedorov into the Arctic sea ice and the search for a suitable ice floe for Polarstern to become frozen in and drift with for the upcoming year. The transiting days aboard were filled with lectures on science topics involved in MOSAiC, but also with work in smaller groups to apply the new knowledge. We were also taught about the instruments that later were installed on the sea ice as part of the Distributed Network (DN) in a radius of fifty kilometer around RV Polarstern. As we were on a Russian icebreaker and many of the early career participants did not speak any Russian, we got some Russian lessons on board from our Russian fellows and the crew.

The “Coolest” School: MOSAiC School Lectures aboard Akademik Fedorov

Lectures aboard the Fedorov covered a wide range of topics, e.g. clouds in the Arctic system, the surface energy budget or sea ice, including their parametrization in weather and climate models. The lecturers' presentations provided us with a good idea on the current state-of-the-art research including current gaps, encouraging us - the young scientists - to tackle these unsolved questions in our future careers.

Jessie Creamean, for example, from the University of Colorado, Boulder, US, explained in her lecture how aerosols from the ocean or the ice can act as absorbers and reflectors of radiation, or can become condensation nuclei for clouds, affecting cloud conditions, precipitation and radiative forcing. Revealing just one of the interdisciplinary connections between sea ice, bio-geo-chemistry and atmospheric physics in MOSAiC emphasize the importance of the bigger picture. Jessie Creamean also showed us the instrument to measure the aerosols during the MOSAiC expedition. This was one of the great things about the MOSAiC school: we got to listen to the presentation but then also got to see and work with the instruments first hand. While we were still searching for the ice floe, we helped setting up and preparing the instruments used in the Distributed Network, such as snow buoys or a seasonal ice mass balance buoy (SIMB3) that we later deployed on the ice.

Jari Haapala (Finnish Meteorological Institute), Marc Oggier (University of Alaska Fairbanks, US) and Michel Tsamados (University College London) taught us about sea ice from first principles over small scale microphysics to sea ice dynamics, giving us an idea about the complexity, variability and behaviour of this, I have to say, beautiful substance.

Daniel Watkins from the Oregon State University, USA introduced to us Ice Watch, a system which coordinates the collection and archival of sea ice observations recorded on ships in the Northern Hemisphere. Every hour two of us would walk to the uppermost deck and look at the sea ice for ten minutes to evaluate its properties, e.g. type, thickness, coverage, snow cover or algae growth underneath. Watching and reporting the sea ice to the comprehensive data set that Ice Watch is maintaining, provided us with the opportunity to actually apply what we have learned during lectures, thereby contributing to actual science community efforts.

Thomas Rackow who is a climate scientist from the Alfred Wegener Institute in Germany provided us with an introduction to the modelling side of Arctic research. Amongst others, he taught us how to implement a sea-ice drift forecast in the programming language Python. The forecasts we actually produced together with him aboard were used to pin down the area to search for a suitable MOSAiC floe. Thomas Rackow also showed us how to create the daily weather forecast using data from the European Center for Medium-Range Weather Forecasts (ECMWF) for spatial maps as well as data from the forecasting model ICON to predict vertical profiles at our location in the ice. Students were then able to make a daily weather forecast with vital information about visibility, temperatures and wind.

However, we did not only attend science lectures: Shannon Hall, a journalist from the US, told us about her workflow and how to work with the media as a young scientist. Leaving our science bubble once in a while and communicating our results to a broader public would be really important. We also got some very viable input from the teachers on how to transfer our knowledge to students and a broader public on our way back.

In total, we had 42 hours of lectures on this cruise, reaching from topics like fish in the Arctic Ocean and organisms in the brine channels of sea ice to atmospheric, ocean and sea icephysics to bio-geo-chemistry lectures explaining how ocean acidification works. Every single one of us students, who are covering many different disciplines, learned something totally new and exciting, in particular how important a more multidisciplinary approach is for our own research.

Phase 2 - Building a Distributed Network of Instruments in the Central Arctic Ocean

The Distributed Network is a key element in the MOSAiC project, giving context to the point measurements done at the main Polarstern ice camp. Being set up in a fifty-kilometer radius around the main floe by the Russian support icebreaker Akademik Fedorov, it will capture the grid cell variability of sea ice, atmospheric and oceanic fluxes and other important parameters within the entire area monitored during MOSAiC. This is crucial knowledge vital to modellers trying to improve their climate models.

Once, Polarstern had found a suitable ice flow to drift with, the set-up of the DN around Polarstern could start. Three L-Sites, where L stands for large, had to be placed in a triangle around Polarstern. Amongst others, students were strongly involved in the set-up of instruments and other tasks on the ice. While some of the students carried out ice surveys, which included measurements of sea ice thickness and properties of the floe, others helped to set up various instruments such as an Atmospheric Surface Flux Station, Autonomous Ocean Flux Buoys or Ice Tethered Profilers, all used to retrieve data from the atmosphere, sea ice and deeper ocean.

Polar Bear Watch and Collateral Duties

To make sure our colleagues can safely work on the ice, polar bear were watched for continuously. For that, we were allowed to go on the ship’s bridge (normally not permitted). From here, we scanned the horizon with binoculars for “white bears”. Even though it was amazing to see polar bears on our way into the Arctic, we were even happier that we did not encounter any bears while working on the ice. No matter how cute and amazing they are – they are still apex predators and very dangerous for humans. Personally, the polar bear watch also provided me with some important time to calm down, watching the work on the ice from quite a different angle and gazing in amazement at the Arctic landscape during that beautiful time of the year, just before polar night would start and the sky was all pink and blue.

Other duties included cargo operations, drilling holes for various instruments or the transport of both instruments and people with snowmobiles. Whatever job we carried out on the ice, there was this feeling of “tired but happy” after we got back onto the ship after a long working day on the ice – a moment to contemplate and appreciate being involved with polar science.

Experiencing the Arctic Environment and Field Work

Due to the calm weather, the great teamwork, and the experience of our Russian colleagues from the Russian Arctic and Antarctic Research Institute (AARI), we finished the set-up of the DN in record time, just before polar night came in. Very suitable ice floes were chosen for the installation of the DN instruments. In less than 24 days, we deployed 106 sensors on 64 scientific sites, including the L-, M- and P-sites. We also transferred people, cargo, fuel and food to Polarstern before we left them on their own for their long journey through the slowly darkening Arctic.

I had a unique time aboard the Akademik Fedorov and would like to thank those who made this possible for all of us to attend. Not only have we learned a lot about how to carry out a ship-based expedition and the logistics behind it, but also about decision making and how important it is to have experienced people aboard. This expedition leaves us with a new mantra: you always have to cope with the unexpected, as nothing ever goes as planned, but if you prepared well enough, there is always a way to make it work.

On another note: we really got to see the so-called “new” Arctic. The central Arctic used to be full of several year old and thick (multi-year) ice, in this time of the year in our location but we encountered an ocean full of one year old (first-year) ice. Experiencing how difficult it was to find a suitable home for Polarstern and seeing how thin, how disintegrated and weak the ice is now, while people told us about how the ice used to be ten years ago, gave us a new sense of urgency and reassured us in why we are working in climate science.

What the Arctic Is

At the same time, this expedition has had a very positive impact on me. Feeling the temperature dropping because of radiative cooling while the sky clears, seeing with my own eyes the impact of wind and clouds on the conditions and how divers sea ice actually can be, enables me to now much better understand the entire Arctic system. We witnessed cracks suddenly opening up and slowly growing between the instruments and our ship; we saw the path of our ship through the ice being completely pressed back together; we woke up in the middle of the night from the scratching and squeaking of the ice trying to crush the ship. This is what makes you realize the immense forces at work, leading to the pressure ridges and gigantic leads you always read about in books. This is what makes you understand the processes that you are trying to parameterized in models. Now, I have a much better idea about what the Arctic coupled system is. The perfect ending of this incredible adventure were northern lights just before we arrived back in Tromsø.

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