[If you think climate stability is a good thing, you may find this
links and images in on-line article]
‘Things are getting weird in the polar regions’
By Chris Mooney
November 21 at 8:31 AM
As extraordinarily warm temperatures continue in the Arctic —
temperatures tens of degrees Fahrenheit above normal for this time of
year in some locations — Arctic sea ice, a key indicator of the overall
state of this system, seems to be responding in kind.
It is kind of unbelievable: On Nov. 19, the extent of Arctic sea ice was
nearly 1 million square kilometers lower (8.633 million vs 9.504
million) than it was on that date during the prior record low year of
2012, according to data from the National Snow and Ice Data Center. On
Nov. 20, the gap widened further, with 8.625 million square kilometers
in 2016 versus 9.632 million in 2012.
This is happening in a time of year when ice is supposed to be spreading
across the polar ocean — yet instead, it is flat or even declining a
“I think that it’s fair to say that the very slow ice growth is a
response to the extreme warmth (still ongoing as of today),” said Mark
Serreze, director of the National Snow and Ice Data Center in Boulder,
Colorado, by email on Sunday. “Over the past few days, extent has
actually decreased in the Arctic, and while I don’t think that such a
short term decline is unprecedented for this time of year, it is highly
unusual, for November is a month when we normally see a quite rapid ice
It may be time for a refresher on why this matters and why it is so
consistent with climate change research going back many decades. The
fear (and it’s not just a fear any longer, really) is that there is
something called a “feedback” in the Arctic climate system.
As the climate warms, there should be less sea ice covering the Arctic
ocean – and indeed, we’ve seen great declines. But as sea ice falls, the
darker ocean should also absorb more energy from sunlight in the summer,
energy that the lighter colored ice would have reflected away. This
heat, contained in the ocean, would also prevent sea ice formation.
Recent trends in the Arctic seem heavily consistent with this idea.
And as if the Arctic data isn’t enough, at the very same time, ice
around Antarctica is also pushing surprising new lows:
Antarctic sea ice extent on Nov. 19 also represented a record low for
this time of year, based on the center’s data. The dataset in question
goes back to the year 1979.
“Why Antarctic extent is also very low right now is something we are
still puzzling over,” said Serreze. “However, there’s really no
connection between the extreme mutual anomalies in the two hemispheres
that we are aware of. We have to wait and see what happens. Having said
this, things are getting weird in the polar regions.”
The Antarctic decline is particularly bewildering because just a few
years ago, the debate was instead over why floating Antarctic sea ice
was pushing record highs, not record lows — and why this was happening
even as the continent’s glaciers were losing considerable mass. Despite
a major lack of clarity about what this phenomena meant, many climate
change doubters seized on the Antarctic sea ice behavior as a key reason
for pushing their contrary message. Now, that argument seems to be
vanishing for them.
While scientists are still trying to understand all aspects of the
Antarctic sea ice system, one intriguing study published earlier this
year linked a recent sea ice expansion in the region to behavior in the
tropical Pacific ocean. It focused specifically on a cycle in the
climate system called the Interdecadal Pacific Oscillation or IPO, that
was also connected to a global warming “pause” or slowdown in the
mid-2000s. However, that tropical Pacific pattern has since shifted —
which may be contributing to sea ice losses around the Antarctic.
Gerald Meehl, the lead author of that study and a climate scientist at
the National Center for Atmospheric Research, told me in an email in
late October that a pattern of lower Antarctic sea ice is “what you’d
expect in an El Nino, as well as transition to positive IPO, so trend
for next 5-10 years should be negative, with year-to-year variations.”
That comment came at a time when the Antarctic ice was low, but not yet
at record low levels, as it is now.
We don’t know all the causes of what’s currently happening in either the
Arctic or Antarctic. It’s certainly possible that the lows we’re seeing
now are an extreme, perhaps tied to the aftermath of the powerful
2015-2016 El Nino, and conditions will soon push more back towards the
range of what’s normal as that event continues to fade. It’s important
to remember that the data presented above are a snapshot in time, and
that can’t substitute for a scientific analysis of trends.
But as we steer the planet into the unknown, the default position should
probably be to expect surprises — surprises not unlike those that we’re
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