A marine oasis in the Arctic resists the onslaught of global warming

July 7 () –

Amidst the vast frozen and barren terrain of the Arctic lies a unique marine ecosystem that supports a diverse web of natural life that it is managing to resist climate change, so far.

Kent Moore, a professor of atmospheric physics at the University of Toronto Mississauga, is studying an extension of 26,000 square meters known as polynyathe name of a year-round area of ​​open water surrounded by sea ice.

Located in the north of Baffin Bay, between Canada and Greenland, creates a relatively warmer microclimate with fresh melt watertriggering an abundant phytoplankton bloom each spring.

The site attracts various species of fish, birds, walruses, narwhals, whales, seals, and polar bears that come to feed, mate, and rest. For several millennia, the polynya has also been a traditional food source for local indigenous peoples.

Scientists refer to this site as the North Water (NOW) polynya, while it is called Sarvarjuac by Canadian Inuit and known as Pikialasorsuaq among Greenlandic Inuit.

“The Arctic is mostly like a desert,” Moore said. it’s a statement. It is difficult for a large number of wildlife to survive. “But North Water is quite amazing, because it’s the most biologically productive ecosystem in the region… You can think of it as an oasis in the Arctic,” she said.

The NOW lies below the Nares Strait, a 40km by 600km waterway that separates northwestern Greenland from Ellesmere Island, ringed by the oldest and thickest sea ice in the world. Each winter, arcs of ice up to 100 kilometers in length form along the northern and southern ends of the strait. They stabilize the ice for seven to eight months, preventing breaking ice floes from traveling to the NOW.

To understand how global warming is affecting the region, Moore teamed up with two scientists from Environment and Climate Change Canada to study ice arches. Their 2021 study found that ice thinning it is causing these arcs to collapse earlier and earlier each year.

“There’s been a lot of work that suggests that without the bows, NOW will change dramatically,” Moore said. “That change would mean a reduction in productivity, fewer species in the region, and just an overall decline in ecosystem richness.”

Moore recently teamed up again with the same two scientists to examine satellite data showing patterns of ice arch formation and disintegration each winter since 2007. They also developed weather prediction models to estimate how, in the absence of ice arches, the winds will blow the ice downstream towards now.

They found that when no arcs are forming, the presence of sea ice tends to be 10 percent higher than usual. However, despite variations in ice arc activity, biological productivity in the NOW has remained stable. Moore said this may be because the region’s strong winds push ice into and then out of the polynya, leaving no time to disturb the ecosystem. His findings were published in the journal Scientific Reports this month.

“It’s kind of good news, that the polynya appears to be more stable than thought,” Moore said. “We can breathe a little easier on the NOW for years to come.”

But as climate change intensifies, Moore said, the NOW could be at risk. As a critical habitat for so many diverse species and a key contributor to the food security of nearby indigenous communities, he said we need to keep an eye on it.

“The underlying problem is that we are still warming the planet. And there are many other stresses on the environment and animals in that region.“he said. “If you go to a scenario where we lose all the ice in the Arctic, then NOW won’t be there anymore.”