These unique samples may reveal how changes in the Arctic will affect oceans and the global climate

Unique samples recovered during a risky research expedition will boost our understanding of how rapid changes in the Arctic will affect oceans and the global climate, researchers say.

The samples, which were taken in a remote fjord in northeast Greenland, arrived in Tromsø last month and are now awaiting analysis in a freezer room in the cellar of the iC3 Polar Research Hub. 

“That particular section of northeast Greenland has been on the radar for some years, but until now nobody has actually managed to get samples from that place,” said Guillaume Lamarche-Gagnon, who leads a research unit at iC3. “We don't know much about what's happening in those systems, and we hope to find out.”  

 Seen from the outside, the samples collected by the GoNorth expedition look distinctly unimpressive. According to researchers at iC3, however, they have many stories to tell. 

“When we open these up, it will look a bit like when you cut into soil and you dig deep and you see the profile. We want to see how it is built up and analyse what happens with the carbon and the nutrients throughout,” said Ricarda Runte, a PhD researcher. 

“At the top you probably have a more fluffy layer, which is the more biologically active layer that is especially interesting for the those researching biological activities. Further down, you have different layers of sediment that show the accumulation of material with time.” 

“As far as I know, this is the first expedition to ever recover pore water and methane samples from that fjord."

"We already have samples from other parts of Greenland and Svalbard, so now we will try and compare the different systems. What are the controlling factors? Is it more the geology or the topography that is driving the differences between fjords?” 

“And that's why these samples are important, because the systems there are very different than the other systems we have already sampled and help us gain a better overall understanding,” Ricarda said. 

Her own research will focus on the dynamics within the sediments recovered by the expedition. 

“I’m mainly interested in what happens on the sea floor, what goes on within those sediments, especially in terms of the carbon cycle,” she explained. Is it being buried, or is it being re-released? What happens with it?” 

“Off northeast Greenland, there is already much less sea ice, and the glaciers have retreated, so the big question is how future climate change will affect the whole global ocean cycling system."

"It’s really cool and it's very rare to be able to get hold of samples like this.”  

Guillaume emphasized that the samples will be shared by a large interdisciplinary group of researchers, each of them asking questions of their own. 

“We're also going to look at greenhouse gas content in the sediments. So some people are looking at, for example, methane emissions and production in Arctic environments,” he said. “Other team members are looking at a range of biochemical reactions that are happening in that fjord.”  

“Is the carbon basically just staying at the bottom of the ocean doing nothing? Or is it being released back in the in the water column and perhaps fuelling ecosystems in those environments? Is it then being exported to the wider ocean? These are all interconnected systems that we are going to look at.” 

Guillaume highlighted that what happens in remote fjords in Greenland has wider-reaching implications. 

“The melting of the glaciers bordering the fjord affects the fixing of carbon dioxide by plankton and algae, and how carbon is being buried on the sea floor. That is happening near both poles now, and is likely to affect the global climate.”