Topline
2021 has been a year of dramatic change in the Arctic, with greening tundras, infrastructure-destroying permafrost melts and never-before-seen rainfall on the summit of Greenland’s ice cap—not to mention a burgeoning army of destructive beavers—according to an annual U.S. government report.
Key Facts
The Arctic is warming more than twice as fast as the rest of the world, according to the National Oceanic and Atmospheric Administration’s latest Arctic Report Card.
Arctic surface air temperatures from October 2020 to September 2021 were the seventh warmest on record, making it the eighth consecutive year that surface air temperatures were at least 1 degree Celsius over the long-term average, the report said.
Greenhouse gas pollution has led to widespread tundra greening, as taller and more abundant shrubs take root where permafrost has melted.
Known trends such as the retreat of sea ice were confirmed by new data, with 15 of the lowest summer sea ice levels having occurred in the last 15 years.
Increasing stormy weather and Arctic shipping traffic have raised underwater noise levels in the frequency bands used by marine mammals like whales and seals, possibly interfering with their communication.
Humans are also threatened by melting glaciers and permafrost, which can trigger sudden and life-threatening events like tsunamis, avalanches and rockslides.
Schoolchildren play on melting ice at the climate change affected Yupik Eskimo village of Napakiak ... [+]
AFP via Getty Images
Key Background
The Arctic Report Card is a peer-reviewed report issued annually by NOAA since 2006. Intended for a general audience, each report offers an update on Arctic “vital signs” including surface air temperature, terrestrial snow cover, sea ice levels and sea surface temperature. A team of 111 scientists from 12 countries contributed to the 2021 report.
Contra
Despite low salmon harvests probably caused in part by climate change, Alaska Native communities were able to mitigate food security disruptions through cultural and economic practices like food-sharing networks, according to an essay published as part of the 2021 Arctic Report Card.
Big Number
12,000. That’s how many beaver ponds NOAA identified in western Alaska. Expanding beaver populations, possibly taking advantage of a warming climate, have colonized the Alaskan tundra and caused flooding by increased dam-building, occupying twice as many ponds in the region as they did in 2000.
Surprising Fact
The Arctic Report Card devoted special attention to the Greenland Ice Sheet, which experienced three “extreme melt episodes” in July and August, and a historic first—rain at the ice sheet’s 10,551-foot peak on August 14.
What To Watch For
More assessment will be necessary to help stakeholders decide how to respond to melt-induced threats to infrastructure, researchers said.
Tangent
The World Meteorological Organization confirmed a new record high temperature for the Arctic: 100.4 degrees Fahrenheit. It was recorded in the Siberian town of Verkhoyansk, on June 20, 2020, during a prolonged heat wave.
Further Reading
“Rain on glaciers. Ice-free seas. New research shows a transformed Arctic.” (Washington Post)
“Rain falls on peak of Greenland ice cap for first time on record” (Guardian)
#News | https://sciencespies.com/news/melting-arctic-creating-new-crises-from-infrastructure-collapse-to-a-beaver-invasion-researchers-say/
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