The sun shines for twenty-four hours a day in the Arctic summer. The more ocean without snow-covered sea ice means that the ocean absorbs 90% of the solar heat. The Arctic has been seeing enormous changes over the decades to humans pouring fossil fuels into the atmosphere. Combined with climate feedback, the world’s smallest ocean, and land area are warming close to four times faster than Earth.
Now comes news that the old sea ice, which has survived the summer and will stay frozen over the winter, is critical to ice nurseries to piggyback off the old ice reducing the amount of solar heat absorbed by ice the following melt season.
This year, there is a problem; the old ice is being swept into the warm water by high-powered winds where it melts. This is gobsmacking news, and other factors at work may still need to be researched.
Ice that survives the summer melt season endures for another winter. Some ice even survives several summers before finally melting. This happens particularly in the colder regions near the North Pole. Ice that survives the summer is known as perennial ice; battle-scarred from its ordeal, it ends up thicker, rougher and more resilient. It’s an important part of the climate and ecology of the Arctic and it’s disappearing due to global heating.
When sunlight hits the Earth, it’s either reflected or absorbed. Reflected light bounces back into outer space, whereas absorbed light heats the planet. Sea ice covered in snow reflects up to 90% of incoming sunlight, making it a powerful defence against global warming. But as polar sea ice melts due to climate change, sunlight increasingly hits the ocean, where over 90% is absorbed.
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To maintain a healthy perennial ice cover in the Arctic, it’s critical that the ice stays out of warm waters where it might melt in summer. Sea ice moves around the Arctic Ocean as it gets blown by the wind. If it stays in the cold regions, where ice can survive the summer, it has a good shot at becoming perennial ice. If the winds blow it southward into warmer waters, its chances of survival drop dramatically.
In February 2021, my academic colleagues and I observed a startling weather phenomenon in the Arctic. The polar vortex, a ring of anticlockwise-flowing wind that holds a pool of extremely cold air over the Arctic, collapsed, resulting in a new record for the region’s highest surface air pressure. Cold weather then moved southwards at the surface, causing UK temperatures to fall to their lowest level since 1995. In Texas, extremely cold weather paralysed the power grid, leaving four million people without power.
In the Arctic, the breakdown of the polar vortex produced an exceptional pattern of surface winds that swirled clockwise about the centre of the Arctic Ocean like water around a plughole. These swirling winds spun the floating icepack like a spinning top. In doing so, they drove the Arctic’s perennial ice from a relatively safe and cold position north of Greenland into an area where ice increasingly can’t survive the summer: the Beaufort Sea.
The Beaufort Sea is north of Alaska, the NW Territories, and the Yukon.
What happens in the Arctic does not stay in the Arctic, which the world's wealthy nations finally realize. Will they act? Not likely.
The IPCC report was released today, and the world, after a quick scan of the Front Page, Rec list, and recent diaries includes this site, yawns. Hopium is useless now; only worldwide action may prevent some of the worst impacts.
Daily Kos blogger and sea-ice expert FishOutOfWater can be seen weighing in on this disturbing issue at the Sea Ice Forum.