Science expedition finds significant changes in Arctic landscape

Scientists analysed sea ice, recorded ocean currents, and probed life in the Arctic

148-Research-vessel-Polarstern-at-the-North-Pole Breaking ice: Research vessel Polarstern at the North Pole | Esther Horvath

Marine biologist Antje Boetius was a PhD student when she first sailed to the Arctic thirty years ago. The Arctic Ocean’s icy, white expanse had left her amazed.

Boetius is now director of the Alfred Wegener Institute in Bremerhaven, Germany’s biggest polar research institute. On August 3 this year, she returned to the Arctic aboard the same ship of her first journey―the 42-year-old German icebreaker Polarstern.

150-scientists-aboard-the-Polarstern-collecting-mud-from-the-sea-floor Scientists aboard the Polarstern collecting mud from the sea floor | Esther Horvath

It was Polarstern’s seventh journey to the North Pole. Aboard the vessel with Boetius this time was a team of 53 scientists, largely PhD students from across the world, and a crew of 44. Boetius was the team’s leader and chief scientist.

The team began its two-month journey from Tromso, Norway. Their mission: to study the effects of climate change in the Arctic in September, when the extent of sea ice touches the annual low.

150-Antje-Boetius Antje Boetius, chief scientist and the leader of the expedition, gets ready for a sea ice observation flight | Esther Horvath

The scientists say there has been a huge change in the polar landscape in the past three decades. Earlier, it was “extremely difficult and challenging” for the Polarstern to break ice and navigate the sea, but this time it was “shockingly very easy”. The ice was no longer three to four metres thick; it had thinned out to just one metre. Polarstern could just glide past it.

“It doesn’t even break the ice. It just moves through the ice as if it were butter,” says Boetius, who returned with her team to Polarstern’s home port of Bremerhaven in early October.

150-Sea-cucumbers-caught Unearthing knowledge: Sea cucumbers caught at a depth of 4,000 metres in the Arctic Ocean | Esther Horvath

The expedition is scientifically significant because the summer of 2023 was the hottest on record since 1880, according to scientists at NASA’s Goddard Institute of Space Studies in New York. For Boetius and fellow scientists, the loss of sea ice in the Arctic was expected, but the change in landscape nevertheless came as a shock. “Normally you find thriving topical sea algae, but it was all just wide and empty this time. We were shocked because the area we saw was so huge,” says Boetius.

The expedition was connected to the internet via satellite―a first in the North Pole, where even messenger services had been inaccessible. Thanks to the fast internet connection, the team could have the first polar Zoom conference with scientists across the world, and send a robot to explore beneath the ice cover. “This time, we aired it all live on YouTube for scientists across the world to watch in real time. They could literally ask for the robot to be turned left or right for better viewing,” says Boetius.

151-a-sea-angel-or-Clione-limacina A ‘sea angel’, or Clione limacina, caught by the scientists | Esther Horvath

The team explored climate change effects in areas “where no human being has ever been to before”. “To embark on a journey like this is a blessing of a lifetime,” says Esther Horvath, an award-winning documentary photographer who was on her 21st tour of the Arctic.

With the sun shining 24x7, and work continuing in shifts without break, most team members lost their sense of time within a week of the expedition. They tried to keep track of time based on the food they were having. “Fridays are fish; so when you eat fish, you know it is a Friday,” says Horvath. “There is always a bowl of thick stew on Saturdays; Thursdays and Sundays, there are always ice cream after lunch. The baker on board would prepare a variety of breads and a cake every single day. Cake time is 3.30pm, and nobody wants to miss it. In subzero temperatures, you burn so many calories that you need loads of food and tend to eat more.”

151-a-polar-bear-at-an-expedition-site A polar bear at an expedition site | Esther Horvath

As the only photographer in the team, Horvath worked most of the time when she was in the Arctic. “It is challenging to work on sea ice for several hours at a stretch, because the chills can get to you if you do not maintain body temperature by moving around,” she says. She made up for the lost sleep on her return journey; in the first night back home, she slept for 14 hours straight.

Aboard the Polarstern, balancing work and leisure was the survival mantra. The ship had a huge sauna, a pool to play water-ball and a small bar that opened thrice a day. A few scientists formed a band, The Arcwatchers, to pay tribute to life at sea.

152-A-scientist-deploys-a-probe-to-analyse-the-temperature Deep dive: A scientist deploys a probe to analyse the temperature, nutrients and currents in the Arctic waters | Esther Horvath

According to Boetius, half of the people on board were vegetarians. “When I was a student 30 years ago, breakfast aboard the Polarstern was eggs with meat. Lunch was meat soup, and dinner was meat with potatoes. But now, most people, no matter which country they come from, do not want to eat too much meat. So our chef and his team had to be really inventive, because on this two-month expedition one cannot preserve vegetables. We had frozen vegetables and canned vegetables, but the cook was having a really tough time and there was a lot of debate in the mess around food,” she says.

Everyone is given training to protect themselves from polar bear. “Polar bears aren’t friendly; they are always angry,” says Boetius. “They are also very curious. When we have equipment out there on the ice, they tend to bite into the cables and plastic, and hurt themselves in the process of finding something to eat.”

152-in-the-Polarstern-kitchen In the Polarstern kitchen, 3:30pm every day is cake time | Esther Horvath

The team discovered a previously unmapped seamount with amazing biodiversity at a depth of 1,500 metres. It also analysed the thickness and properties of sea ice, recorded ocean currents and their chemical properties, and investigated life in open waters and the ice-covered deep sea. Their data showed significant changes compared to previous expeditions.

“We found hardly any ice algae on the underside of the sea ice,” says Boetius. “Melosira arctica (a major algae species of the region), especially, was missing. It can form metre-long chains and is an important nutrient supplier for the entire ecosystem. The ice looked rather dead this year. Because of the darkening by snow, algae floated up from the water and formed a film under the ice to get some light.