Greenhouse gas emissions transforming the Arctic
into 'an entirely different climate'
Warmest temperatures since 1900 have all occurred
within the past seven years, according to Noaa’s annual Arctic report card
Oliver
Milman in New York
@olliemilman
Tue 8 Dec
2020 18.44 GMTLast modified on Tue 8 Dec 2020 18.47 GMT
https://www.theguardian.com/world/2020/dec/08/arctic-report-climate-crisis-wildfires-ice-loss
The
Arctic’s rapid transformation into a less frozen, hotter and biologically
altered place has been further exacerbated by a year of wildfires, soaring
temperatures and loss of ice, US scientists have reported.
The
planet’s northern polar region recorded its second hottest 12-month period to
September 2020, with the warmest temperatures since 1900 all now occurring
within the past seven years, according to an annual Arctic report card issued
by the National Ocean and Atmospheric Administration (Noaa).
The Arctic
is heating up at a rate around double that of the global average, due to the
human-caused climate crisis.
Some places
were abnormally hot in 2020, with parts of Siberia 9F (5C) above the long-term
average in the first half of the year. In June, the Siberian town of
Verkhoyansk reached 100.4°F, the hottest temperature ever recorded north of the
Arctic Circle.
Meanwhile,
Arctic sea ice shrank to its second lowest summer extent in the 42-year
satellite record in 2020, with the loss of ice and surging ocean heat causing a
burst of ocean plant growth and altered behavior of bowhead whales.
On land,
fierce wildfires tore through parts of the Arctic region while the melting of
permafrost and retreat of ice is increasingly turning parts of the Arctic green
with sprouting vegetation.
“It has
been yet another year of breathtaking changes in the Arctic,” said Jennifer
Francis, the senior scientist at the Woodwell Climate Research Center.
“Temperatures in Siberia have been off the charts most of the year, and the
Arctic passages have been open for shipping much longer than any previous
year.”
The vast
Greenland ice sheet lost mass again in 2020, albeit at a slower rate than last
year, the report card states.
The
continual melting of the world’s glaciers is fueling sea level rise,
threatening coastal cities with flooding. Scientists have been closely
monitoring the ice sheet, as well as its equivalent in Antarctica, to ascertain
how the huge changes under way will impact the environment.
A
tumultuous year in the Arctic has seen the last fully intact ice shelf in
Canada collapse after losing more than 40% of its area in just two days, while
thawing permafrost caused a disastrous oil spill in Russia after a fuel tank
collapsed.
The latest
scientific warning over the changing Arctic will provide further urgency to
international climate talks to mark the fifth anniversary of the Paris climate
agreement.
“The Arctic
is transitioning from a predominantly frozen state into an entirely different
climate, due to emissions of greenhouse gases,” said Laura Landrum, the
associate scientist at the US National Center for Atmospheric Research Climate
and Global Dynamics Laboratory.
“If we do
not bring emission rates down, Arctic climate will change so significantly that
this year’s record low sea ice extents will look large and record warm
temperatures will appear cool compared to what we will experience in the
future.”
Zack Labe,
a postdoctoral researcher at Colorado State University, said the Arctic is
“yelling at us to pay attention”. He added: “Unless we slow global warming by
systematically reducing our greenhouse gas emissions, the chances of our first
‘ice-free’ Arctic summer will continue to increase. This rapid climate change
in the Arctic will continue to have consequences for the entire Earth system.”


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