"Nothing can be taken for granted or planned"

The German research icebreaker Polarstern has been drifting through the Arctic Ocean for a year since autumn 2019. Scientists from 20 nations explore the central Arctic over the course of the year on the MOSAiC expedition. In June 2020, Captain Thomas Wunderlich took command of his colleague Stefan Schwarze. Contrary to the original planning, Polarstern had to leave the ice to carry out exchanges and supplies at Svalbard. Thomas Wunderlich talks about the journey and his expectations.

What was the journey from Svalbard back to the MOSAiC floe like, and how did it compare with Polarstern Captain Stefan Schwarze’s experiences on the way south?

Thomas Wunderlich: We had the advantage of being able to choose our preferred route into the northern ice. There were a number of techniques and analyses that helped us find the ideal position for entering the ice. What’s most important, just as it was back in the days of the early explorers, is to not just charge in blindly. On the southern tour, Stefan Schwarze didn’t have that luxury: he had his position and had to follow the course to Svalbard that was handed to him. It goes without saying that the waters of the outer Arctic ice aren’t subject to the same pressure as in the inner ice, let alone the Central Arctic; the floe dimensions are on a different scale, too. Given these conditions, for the first few days, we made good and rapid progress.

How were the weather conditions?

We had favourable winds and good visibility, and their importance shouldn’t be underestimated. But from 82 ° North, the situation grew ‘tenser’: the ice dynamic increased, and the ice grew thicker. That being said, we never encountered the huge masses of ice that Stefan Schwarze reported. Nevertheless, on the weekend of 13/14 June, the pack ice slowed us to a standstill, forcing us to shut down the engines to conserve our fuel, which we may need every last drop of later on, and which could tip the scales. But as we know: in the polar regions, nothing can be taken for granted, and you have to be ready for anything.

How did it feel to have to ‘park’ the Polarstern, and what challenges did it pose?

Coming to a dead stop like this has the advantage of showing you: nothing about this venture is predictable or can be taken for granted – sometimes you just have to accept your circumstances. In my view, both the voyage out of the ice, led by Stefan Schwarze, and now the transit back into it had their fair share of challenges. The time pressure, dwindling resources and, as a result, a very limited choice of routes on the one hand – but knowing that you’ll be moving from the ‘bad’ ice into the ‘good’ ice; and on the other, having ample resources, but having to move from a ‘good’ situation into an unpredictable one. Nevertheless we also had the good fortune (s. wind) that over the past several days the floe had drifted in our direction, significantly reducing the distance and making it easier to approach. In short: there are always good moments and bad ones. When the bad ones come, the best advice is to keep a cool head and stay calm.                   

What are your hopes for the expedition?

I hope we have a relatively short travel time back to the floe, for the researchers’ sake: the southern drift and the dawning summer still lie before us. I hope we can stay with the floe as long as possible, so that the researchers can accompany it from birth through the end of its lifecycle – even though doing so will pose an enormous challenge for logistics and navigation.

What was the transfer like, and how does it feel to be on board again, after such a long break?

The transfer, I think it’s safe to say, was an emotional one. It’s perfectly normal that, after being away for so long, at first it feels strange to be back on the ship. But after so many years on board, and once you’ve settled back into your cabin, you quickly feel ‘back home’ again, and it seems – just like it always does – like you never left.

And what was it like to be a passenger on the Maria S. Merian?

Traveling on the Maria S. Merian was a nice change of pace. After all, it, too, is a research ship, and research is conducted on board. It was interesting to see what they do with the available resources, and how others do the same type of work. We definitely learned some valuable lessons that we’ll put to use on Polarstern, so as to improve on our already good basis – and mix the best of both worlds.

I’d also like to take this opportunity to thank the crews of the Maria S. Merian and Sonne for their openness, friendliness and hospitality. It was a real pleasure, and we learned a thing or two. But I’m confident the feeling is mutual. You could see it when, just before we finished, they had a chance to visit Polarstern again. Despite her age, they were clearly impressed and full of praise for our ship.

Are there any particularly difficult challenges for the crew, and if so, what are they?

I don’t see any special challenges for the crew. Many of them look at it the same way I do: it’s a job like any other, and every job is unique, including the challenges involved, which you draw on your pool of experience to overcome.

The only thing that might be new is that, though crew transfers and resupply missions were planned and implemented, here more potential delays naturally have to be expected than on other Polarstern expeditions.