Over the last decade, researchers have learned a lot about the polar night — discovering everything from how tiny marine critters migrate up and down in the sea in response to the weak light of the moon, to seabirds that dive into the pitch-black ocean to feast on bioluminescent plankton and krill.
But what is less well known is how the chemistry of Arctic Ocean water changes during this period, when the sun remains completely below the horizon for a full 24-hour day.
Now, in an article published in Nature Geoscience, Norwegian University of Science and Technology (NTNU) researchers report on a surprising trend they discovered in mercury levels in the ocean during the polar night.
“We found that total mercury concentrations in the Barents Sea decreased by about 33 percent from summer to winter,” said Stephen G. Kohler, a PhD candidate at NTNU’s Marine Chemistry and Biogeochemistry group in the Department of Chemistry and first author of the article.
Read more at Norwegian University of Science and Technology
Image: It used to be that researchers didn't study what happens in the Arctic during the polar night because it was difficult to work there. But over the past decade, researchers have ventured into this environment and have come up with surprising findings. Norway's research-dedicated icebreaker, Kronprins Håkon, launched in 2017, is an important tool for this research. (Credit: Robin Hjertnes)