Arctic danger: Report card shows unprecedented warming.
Persistent warming in the Arctic is pushing the region into “uncharted territory” and increasingly affecting the continental United States, scientists said Tuesday.
“We’re seeing this continued increase of warmth pervading across the entire Arctic system,” said Emily Osborne, an official with the National Oceanic and Atmospheric Administration, who presented the agency’s annual assessment of the state of the region, the “Arctic Report Card.”
The Arctic has been warmer over the past five years than at any time since records began in 1900, the report found, and the region is warming at twice the rate as the rest of the planet.
Osborne, lead editor of the report and manager of NOAA’s Arctic Research Program, said the Arctic was undergoing its “most unprecedented transition in human history.”
In 2018, “warming air and ocean temperatures continued to drive broad long-term change across the polar region, pushing the Arctic into uncharted territory,” she said at a meeting of the American Geophysical Union in Washington.
The rising air temperatures are having profound effects on sea ice, and on life on land and in the ocean, scientists said. The impacts can be felt far beyond the region, especially since the changing Arctic climate may be influencing extreme weather events around the world.
The warmer Arctic air causes the jet stream to become “sluggish and unusually wavy,” the researchers said. That has possible connections to extreme weather events elsewhere on the globe, including last winter’s severe storms in the United States and a bitter cold spell in Europe known as the “Beast From the East.”
Some of the findings in the research, provided by 81 scientists in 12 countries, included:
The wintertime maximum extent of sea ice in the region, in March of this year, was the second lowest in 39 years of record keeping.
Ice that persists year after year, forming thick layers, is disappearing from the Arctic. This is important because the very old ice tends to resist melting; without it, melting accelerates. Old ice made up less than 1 percent of the Arctic ice pack this year, a decline of 95 percent over the past 33 years.
Donald Perovich, a sea-ice expert at Dartmouth College who contributed to the report, said the “big story” for ice this year was in the Bering Sea, off western Alaska, where the extent of sea ice reached a record low for virtually the entire winter. The lack of ice and surge of warmth coincides with rapid expansion of algae species in the Arctic Ocean, associated with harmful blooms that can poison marine life and people who eat the contaminated seafood.
Reindeer and caribou populations have declined 56 percent in the past two decades, dropping to 2.1 million from 4.7 million.