The Arctic Is Becoming Wetter and Stormier, Scientists Warn


The Arctic Is Becoming Wetter and Stormier, Scientists Warn

Raymond Zhong
Tue, December 13, 2022 

As humans warm the planet, the once reliably frigid and frozen Arctic is becoming wetter and stormier, with shifts in its climate and seasons that are forcing local communities, wildlife and ecosystems to adapt, scientists said Tuesday in an annual assessment of the region.

Even though 2022 was only the Arctic’s sixth warmest year on record, researchers saw plenty of new signs this year of how the region is changing.

A September heat wave in Greenland, for instance, caused the most severe melting of the island’s ice sheet for that time of the year in over four decades of continuous satellite monitoring. In 2021, an August heat wave had caused it to rain at the ice sheet’s summit for the first time.

“Insights about the circumpolar region are relevant to the conversation about our warming planet now more than ever,” said Richard Spinrad, administrator of the United States National Oceanic and Atmospheric Administration. “We’re seeing the impacts of climate change happen first in polar regions.”

Temperatures in the Arctic Circle have been rising much more quickly than those in the rest of the planet, transforming the region’s climate into one defined less by sea ice, snow and permafrost and more by open water, rain and green landscapes.

Over the past four decades, the region has warmed at four times the global average rate, not two or three times as had often been reported, scientists in Finland said this year. Some parts of the Arctic are warming at up to seven times the global rate, they said.

Nearly 150 experts from 11 nations compiled this year’s assessment of Arctic conditions, the Arctic Report Card, which NOAA has produced since 2006. This year’s report card was issued on Tuesday in Chicago at a conference of the American Geophysical Union, the society of earth, atmospheric and oceanic scientists.

Warming at the top of the Earth raises sea levels worldwide, changes the way heat and water circulate in the oceans, and might even influence extreme weather events like heat waves and rainstorms, scientists say. But Arctic communities feel the impacts first.

“Our homes, livelihoods and physical safety are threatened by the rapid-melting ice, thawing permafrost, increasing heat, wildfires and other changes,” said Jackie Qatalina Schaeffer, an author of a chapter in the report card on local communities, the director of climate initiatives for the Alaska Native Tribal Health Consortium and an Inupiaq from Kotzebue, Alaska.

Between October 2021 and September, air temperatures above Arctic lands were the sixth warmest since 1900, the report card said, noting that the seven warmest years have been the last seven. Rising temperatures have helped plants, shrubs and grasses grow in parts of the Arctic tundra, and 2022 saw levels of green vegetation that were the fourth highest since 2000, particularly in the Canadian Arctic Archipelago, northern Quebec and central Siberia.

A new chapter in this year’s report deals with Arctic precipitation. Measuring snow, rain and freezing rain is tricky there: In the northernmost reaches of the region, there aren’t many weather gauges. Those that are in place might not measure snow accurately because of windy conditions.

Instead, scientists have begun combining direct measurements with sophisticated computer modeling to get a fuller picture. These methods have given them confidence to say that precipitation levels have increased significantly in the Arctic since the mid-20th century. This year was the region’s third-wettest since 1950, the report card said.

Because of warmer temperatures, though, extra snow doesn’t necessarily remain on the ground. Snow accumulation in the Arctic was above average during the 2021-22 winter, the assessment said. But by June, snow cover in the North American Arctic was the second-lowest on record. In the Eurasian Arctic, it was third lowest.

Three main factors could be increasing precipitation in different parts of the Arctic, said John Walsh, a scientist at the International Arctic Research Center of the University of Alaska Fairbanks, and an author of the report card. First, warmer air can hold more moisture. Second, as sea ice retreats, storms can suck up more open ocean water.

Indicators of sea ice rebounded this year after near-record-lows in 2021, but they were still below long-term averages, the assessment found. March is typically when the ice is at its greatest extent each year, September its lowest. At both points this year, ice levels were among the lowest since satellites have been making reliable measurements.

The third factor is that storms are passing over warmer water before reaching the Arctic, feeding them with more energy, Walsh said. The remnants of Typhoon Merbok traveled over unusually warm water in the north Pacific in September before pummeling communities along more than 1,000 miles of Alaskan coast.

The Greenland ice sheet has lost ice for the last 25 years, and this year was no different. But what stood out to scientists was an extraordinary burst of melting in September, the kind of event that would normally be seen in the middle of summer.

In early September, a high pressure system brought warm, wet air that sent temperatures in parts of Greenland to as high as 36 degrees Fahrenheit above normal for that time of year. More than a third of the ice sheet experienced melting, according to the report card. Later that month, the remnants of Hurricane Fiona traveled over the island and caused further melting over 15% of the ice sheet.

The seasons are blending together across the Arctic, said Matthew Druckenmiller, a scientist with the National Snow and Ice Data Center at the University of Colorado Boulder, and an editor of the report card. Just last week, the mercury hit 40 degrees Fahrenheit in the northern Alaskan community of Utqiagvik, smashing winter records.

“At this time of year, the sun’s not even rising” in that part of Alaska, Druckenmiller said.

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