Worrying
signs from the Arctic
Author
Headshot
By David
Gelles
https://www.nytimes.com/2024/12/17/climate/worrying-signs-arctic.html
In a year
full of troubling signs that Earth’s climate is rapidly changing, some of the
most alarming signals came from the Arctic.
The thawing
tundra has become a source of greenhouse gas emissions, instead of locking away
carbon. Sea ice levels are near historic lows. Fires are getting worse. Surface
air temperatures are near record highs. And, yes, the polar bears are in
trouble.
“There’s a
lot going on in the Arctic,” said Brendan Rogers, an Arctic scientist at the
Woodwell Climate Research Center in Falmouth, Mass. “There’s big changes in the
rivers, and with salmon, and big changes in the atmosphere, and with sea ice,
and ocean productivity, and the fauna.”
One area of
particular concern to Rogers is the increase in wildfires. Fire season is
getting longer, the fires are burning bigger and hotter, and more fires are
being ignited by lightning strikes.
“The primary
reasons are all directly tied to climate change,” he said.
Some fire
activity is natural, of course. But Rogers said that, because of climate
change, “the fires are happening too quickly, too much; they’re also increasing
in severity and intensity.”
Another
point of acute concern: Parts of the Arctic that have long stored carbon are
now turning into sources of carbon.
Last week,
the National Oceanic and Atmospheric Administration announced that the Arctic
tundra has in recent decades been “adding more carbon dioxide to the atmosphere
than it has removed, a reversal from the usual state of affairs since the peak
of the last ice age,” my colleague Raymond Zhong wrote.
What happens
in the Arctic doesn’t stay in the Arctic
A warmer
Arctic has the potential to alter global weather patterns. It’s the temperature
gradient between the polar regions and the Equator that drives air currents
that move high and low pressure systems around the globe.
Major
changes to the Arctic will most likely have far-reaching consequences, though
scientists can’t yet predict exactly what they will be.
“There’s a
lot about the Arctic that does very directly affect the rest of the world,”
Zhong told me.
The thawing
Arctic is also shaking up geopolitics.
With sea ice
melting, new shipping lanes are opening up. As a result, Russia and China have
sought to project their influence in the region in recent years.
That has led
Canada to step up its military presence in the region and seek to work more
closely with the United States. Announcing the move, the Canadian government
called climate change “the overarching threat” to control of its Arctic
territories.
Meanwhile,
tensions between Russia and the West have resulted in scientists being shut out
of the Russian Arctic, compromising efforts to collect reliable data on one of
the largest and most significant swaths of the Arctic on Earth.
It’s too
early to say we’ve hit a tipping point
Scientists
can’t yet say that the changes being observed in the Arctic are irreversible,
or that they are accelerating and compounding.
And while
the tundra is now a carbon source, other permafrost areas, including beneath
boreal forests, are still net carbon sinks, or natural reservoirs that store
more carbon than they emit. (Though the forests are burning at an alarming
rate.)
Still,
things are moving fast up north.
The Arctic
is warming four times as fast as the rest of the planet. In the waters that
connect the Atlantic and the Pacific Oceans in northern Canada, sea ice was the
lowest ever recorded in the period from October of 2023 to September.
In Canada’s
Western Arctic, thawing permafrost is triggering landslides and making it a
near certainty that some villages will have to move. This summer, the eastern
half of Hudson Bay, home to the world’s most-studied polar bears, was ice-free
a month earlier than usual.
A group of
scientists recently warned that the Arctic could experience its first day that
is practically ice-free by 2027. And, for the 11th year in a row, the Arctic
was more abnormally warm than the world as a whole.
In a recent
guest essay for the Times’ Opinion section, a former park ranger, Jon Waterman,
revisited Arctic landscapes he first encountered 40 years ago and witnessed a
world transformed by fires, landslides, new vegetation and melting permafrost.
When
Waterman asked a villager, sweating in the heat, what could be done about
climate change, he replied, “Maybe people down south could reduce their
emissions.”
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