Wednesday , January 20 2021

Arctic Report Card Documents 'Cascading Effects' of Warming Ocean Temperatures



The Arctic has experienced the "most unprecedented transition in history" in terms of warming temperatures and melting ice, and these changes may be the cause of extreme weather around the globe, according to the 2018 Arctic Report Card of the National Oceanic and Atmospheric Administration.

The annual report released Tuesday says rapid warming over the past three decades has led to a 95 percent decline in Arctic's oldest and thickest ice. This research comes as world leaders convene at the U.N. climate summit in Poland this week where they are debating whether to embrace the findings of a October report by the International Panel on Climate Change.

The melting of sea ice is one of the most conspicuous examples of climate change in the Arctic, and scientists say it may be the catalyst for extreme environmental events across the globe.

According to NOAA, the Arctic is warming at the rate of the rest of the globe, which melts some of the oldest ice in the region. That old ice is resistant to melting and helps keep Arctic cold in the summer when most of the ice melts off, says Emily Osborne, lead editor of the report and a researcher with NOAA's Arctic Research Program.

"When observations started back in the '70s, we had about 16 percent of the ice cover in the Arctic [that] was very old or more than four years old, "she tells Here & Now's Robin Young. "And this year we're seeing that … less than 1 percent of the Arctic ice pack is very old, multiyear ice."

Scientists have reported record low sea levels in the Bering Sea, off western Alaska, during the winter when ice is supposed to accumulate, according to the report. Instead, the Bering Sea lost a section of ice the size of Idaho.

Without the sea ice cover to deflect sunlight, the ocean will absorb more sunlight and the planet will continue to get warmer, Osborne says. According to the report, Arctic Ocean temperatures are rising and sea ice levels are falling at rates not seen in the past 1,500 years.

Sea ice melt does not directly lead to sea-level rise, but warmer ocean temperatures in the Arctic could, says Robert Graham, and climate scientist at the Norwegian Polar Institute.

"This melting is not going to affect sea-level rise in itself because ice is already in the ocean," Graham told Here & Now's Jeremy Hobson earlier this year. "But if this leads to a larger warming area of ​​the Arctic, you could start melting land glaciers on Greenland that could contribute to sea-level rise."

Along with the lack of ice and rising temperatures, Osborne says harmful algae blooms in the Arctic Ocean are poisoning marine life and affecting coastal communities that rely on the ocean for their economic survival.

Arctic temperatures can also alter the behavior of the jet stream, the atmospheric currents that influence global weather, Osborne says. A wavy jet stream can cause extreme weather, such as last year's winter storms in the US and an unusual cold snap in Europe this March referred to as "The Beast From The East."

"As the Arctic is warming up at this really fast rate, the jet stream is actually slowing down, and as it slows it creates these wobbles, " she says. "When we have this wavy jet stream pattern, which can really persist as we saw in 2018 for months at a time, we have these really different air masses reaching different parts of the globe."

The report also found that reindeer and caribou populations have declined 56 percent over the past two decades due to environmental changes in the Arctic. And microplastic is accumulating in higher concentrations in the Arctic Ocean than in all other ocean basins in the world.

As Arctic ice continues to melt, opening new waterways in the Arctic Ocean can also have geopolitical consequences as countries compete for new resources, Osborne says. It could also leave the U.S. Northern border and Alaska more vulnerable.

And yet, the U.S. has joined with Saudi Arabia, Kuwait and Russia in refusing to endorse the IPCC report. President Trump has also said he will withdraw the U.S. from the Paris Agreement.

Despite the lack of support in Washington, Osborne says scientists are focusing on arming people in the "ground zero of climate change," such as those who live in the Arctic, with this information, so they can adapt to environmental changes.

"I would not say that it's too late," she says. "I'm not ready to give up hope."

Copyright 2018 NPR. To see more, visit https://www.npr.org.


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