A “crazy year” in the Arctic has led to the second lowest level of sea ice in the region, scientists said on Monday.
Researchers from the National Snow and Ice Data Center said the minimum was most likely reached on September 15, with 1.44 million square miles of ocean covered in ice. Since then, as temperatures have dropped and new ice has formed, the coverage has increased.
Since satellite measurements of sea ice began four decades ago, there was a lower minimum in 2012 alone, when 1.32 million square miles were measured. The low for 2020 was nearly a million square miles lower than the average annual low between 1
This year is also a worrying period: the 14 lowest ice years have occurred in the last 14 years. Many scientists expect that the Arctic could be devoid of ice in the summer long before the middle of the century.
“It was a crazy year in the north, with sea ice in near-record lows, 100-degree heat waves in Siberia and massive forest fires,” Mark Cerese, director of the National Snow and Ice Data Center, said in a statement. “We’re heading for a seasonal ice-free ocean and this year is another nail in the coffin.”
Arctic sea ice rises maximally in autumn and winter and then melts in spring and summer. This year’s high, 5.9 million square miles, was reached in early March.
The researchers note that, as every year, their announcement at a minimum is in advance: A short warm spell or changing winds can bring more melting. This has happened twice in this century.
Temperatures have soared in much of the Arctic this summer. In late June, Siberia was engulfed in a stagnant air zone that continued to heat up. This led to record temperatures: Verkhoyansk, Russia, 400 miles north of Anchorage, Alaska, reached 100 degrees Fahrenheit one day.
Sea ice is shrinking by more than 13 percent per decade from the 1981-2010 average as global warming affects the Arctic more than any other part of the world. The region is warming more than twice as fast as any other.
The loss of sea ice plays a role in this rapid warming. The ice reflects most of the sunlight that hits it. But when it melts, more ocean opens up. The ocean surface is darker and absorbs more sunlight, radiating energy as heat. This leads to more warming and greater loss of ice, as the process continues in what scientists call feedback.