BERLIN | After a year of exploring the Arctic, the largest expedition ever led to the North Pole returns to Germany on Monday, sounding the alarm over the melting sea ice caused by global warming.
After 389 days at sea, the icebreaker Polarstern from the German Alfred-Wegener Institute is due to return to its home port of Bremerhaven, in northwestern Germany, around 8:30 am local (6:30 am GMT).
Due to the coronavirus pandemic, the events planned at the end of this long journey have been reduced, but a press conference must be held in the middle of the day.
When it comes time to return, the atmosphere within the international MOSAIC expedition is far from euphoric as scientists have been able to grasp the extent of climate change in the vast Arctic Ocean.
“We watched how the ice floes are dying” in summer, expedition leader Markus Rex told AFP, reached by satellite phone on board the ship.
For this climatologist and physicist, the finding is clear. “If climate change continues like this, then in a few decades we will have an ice-free Arctic in the summer.”
During the outings on the ice floe to take measurements or take samples, the entire expedition was able to observe this development which the researcher considers “impressive”.
“Directly at the North Pole, we found [en été] melted, thin, crumbly ice, ”Mr. Rex testified, also referring to“ surfaces of liquid water as far as the eye can see, up to the horizon line ”.
A diagnosis confirmed by satellite observations in the United States which revealed that the summer sea ice had melted to the second smallest area on record, after 2012.
In winter when they faced absolute night for several months, scientists also measured temperatures much warmer than a few decades ago.
In total, several hundred experts and scientists from 20 different countries have stayed, taking turns on the ship which slipped with the ice according to the polar drift, this ocean current which flows from east to west in the ‘Arctic ocean.
To carry out the research, a camp was established, moored to a piece of ice floe and made up of four scientific stations within a radius of up to 40 km around the boat.
Experts collected more than 150 terabytes of data as well as numerous samples of ice and water.
They promise to deliver valuable information to understand “the complex processes” at play in the North Pole that lead to a more accelerated global warming in this region than in the rest of the world.
For a year, they were able to observe more than a hundred parameters. This allowed “a breakthrough in the understanding of the Arctic climate system”, according to Markus Rex.
The mission, with a budget of 140 million euros, studied the atmosphere, the ocean, the sea ice and the ecosystem to collect data assessing the impact of climate change.
The full analysis of the data until their release in scientific publications should take a year or two.
The goal is to develop climate prediction models to determine what heatwaves, heavy rains or storms will look like in 20, 50 or 100 years.
“To establish climate models, we need in situ observation,” Radiance Calmer, an atmospheric science researcher at the University of Colorado at Boulder, told AFP. She stayed, from June to September, on the Polarstern.
Since the departure of the German research vessel from Tromsø, Norway on September 20, 2019, scientists have faced long months in absolute night, temperatures plunged to -39.5 ° C and received a visit from a twenty polar bears.