National Snow and Ice Data Center
Arctic sea ice was at a record low maximum extent for the second
straight year, according to scientists at the National Snow and Ice Data
Center (NSIDC) and NASA.
"I've never seen such a warm, crazy winter in the Arctic," said NSIDC
director Mark Serreze. "The heat was relentless." Air temperatures over
the Arctic Ocean for the months of December, January and February were 2
to 6 degrees Celsius (4 to 11 degrees Fahrenheit) above average in
nearly every region.
Sea ice extent over the Arctic Ocean averaged 14.52 million square
kilometers (5.607 million square miles) on March 24, beating last year's
record low of 14.54 million square kilometers (5.612 million square
miles) on February 25. Unlike last year, the peak was later than average
in the 37-year satellite record, setting up a shorter than average ice
melt season for the coming spring and summer.
According to NSIDC, sea ice extent was below average throughout the
Arctic, except in the Labrador Sea, Baffin Bay, and Hudson Bay. It was
especially low in the Barents Sea. As noted by Ingrid Onarheim at the
Bjerknes Centre for Climate Research in Bergen, Norway: "A decrease in
Barents Sea ice extent for this winter was predicted from the influence
of warm Atlantic waters from the Norwegian Sea."
Scientists are watching extent in this area because it will help them
understand how a slower Atlantic Meridional Overturning Circulation
(AMOC) may affect Arctic sea ice. "Some studies suggest that decreased
heat flux of warm Atlantic waters could lead to a recovery of all Arctic
sea ice in the near future," said NSIDC senior research scientist
Julienne Stroeve. "I think it will have more of a winter impact and
could lead to a temporary recovery of winter ice extent in the Barents
and Kara seas."
This year's maximum extent is 1.12 million square kilometers (431,000
square miles) below the 1981 to 2010 average of 15.64 million square
kilometers (6.04 million square miles) and 13,000 square kilometers
(5,000 square miles) below the previous lowest maximum that occurred
last year.
This late winter, ice extent growth in the Arctic has been sluggish.
"Other than a brief spurt in late February, extent growth has been slow
for the past six weeks," said Walt Meier, a research scientist at the
NASA Goddard Space Flight Center. Meier is an affiliate scientist at
NSIDC and is part of NSIDC's Arctic Sea Ice News and Analysis team.
Ice extent increases through autumn and winter, and the maximum
typically occurs in mid March. Sea ice then retreats through spring and
summer and shrinks to its smallest or minimum extent typically by mid
September.
The September Arctic minimum began drawing attention in 2005 when it
first shrank to a record low extent over the period of satellite
observations. It broke the record again in 2007, and then again in 2012.
The March Arctic maximum has typically received less attention. That
changed last year when the maximum extent was the lowest in the satellite record.
"The Arctic is in crisis. Year by year, it's slipping into a new
state, and it's hard to see how that won't have an effect on weather
throughout the Northern Hemisphere," said Ted Scambos, NSIDC lead
scientist.
NSIDC will release a full analysis of the winter season in early April, once monthly data are available for March.
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