A “crazy year” in the Arctic has resulted in the second lowest sea ice in the region, scientists said Monday.
Researchers from the National Snow and Ice Data Center said the minimum was most likely hit on September 15, when 1.44 million square miles of ocean were covered in ice. Since then, coverage has increased with falling temperatures and new ice formation.
Since satellite measurements of sea ice began four decades ago, there has only been a lower minimum in 2012, when 1.32 million square miles were measured. The 2020 minimum was nearly a million square miles below the average annual minimum between 1
An alarming phase continues this year as well: The 14 lowest ice years have occurred in the last 14 years. Many scientists expect that the Arctic could be ice-free in the summer well before the middle of the century.
“It’s been a crazy year in the north, with sea ice at a record low of 100 degrees heat waves in Siberia and massive forest fires,” said Mark Serreze, director of the National Snow and Ice Data Center, in a statement. “We are on our way to a seasonally ice-free Arctic Ocean, and this year is another nail in the coffin.”
The Arctic sea ice grows maximally in autumn and winter and then melts in spring and summer. The maximum that year, 5.9 million square miles, was hit in early March.
The researchers found that, like every year, the announcement of a minimum was tentative: a brief warm period or changing winds could bring more melts. It has happened twice in this century.
Temperatures rose across much of the Arctic that summer. At the end of June, Siberia was enveloped in a zone of stagnant air that was constantly warming. This led to record temperatures: Verkhoyansk, Russia, 400 miles further north than Anchorage, Alaska, hit 100 degrees Fahrenheit one day.
Sea ice has shrunk 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 up more than twice as fast as any other.
The loss of sea ice plays a role in this rapid warming. Ice reflects most of the sunlight that hits it. But when it melts, more ocean is exposed. The sea surface is darker and absorbs more sun rays, whereby the energy is given off again as heat. This leads to more heating and more ice loss, with the process continuing in what is known as a feedback loop.