Climate change is causing the Arctic Ocean’s sea ice to melt away. When the polar ocean loses its cover of sea ice, carbon dioxide uptake increases disrupting the food web in the water according to a study in the journal Science co-authored by researchers from the University of Gothenburg.
By comparing data from a long list of Arctic expeditions, researchers have been able to see how the pH of the ocean north of Alaska and Siberia has decreased rapidly. In recent decades, the rate of acidification of the Arctic Ocean has been 3–4 times faster than in other oceans. This is because more carbon dioxide is taken up by the sea water when the surface is in direct contact with the atmosphere without a barrier of ice. In the past, the sea ice has kept the sea water close to the North Pole from being saturated with carbon dioxide.
“The time-series of pH measurements made in the Arctic Ocean is long. The oldest are from an expedition in 1994, when the ice sheet was extensive and thick, and measurements were taken in the leads between the ice floes. On the expedition in 2014, the icebreaker Oden was able to travel in open water half way from Siberia to the North Pole,” says Leif Anderson, researcher in marine chemistry at the University of Gothenburg and one of the authors of the study.
Read more at University of Gothenburg
Image: As early as the expedition in 2014 with the icebreaker Oden, the researchers could see that the sea ice coverage was greatly reduced in the Arctic.
(Photo: Jorien Vonk)