Dear Peter,
That's most interesting. But, if the Arctic was ice free, why wasn't
there a methane excursion - or perhaps there was? Do we have records
going back 100,000 years, e.g. from ice cores?
(I'm copying to John Gorman, Albert Kallio and Sam Carana as they'll be
interested in your response.)
Best wishes,
John
---
P. Wadhams wrote:
Dear John, This published work by Barber on rotten ice has been
questioned in terms of the possibility that he has mistaken a local
anomaly for a basinwide effect. Also, regarding when there was last an
ice-free Arctic, the Danish Geological Suvey has found two periods in
the last 100,000 years when there was warm-water plankton over the
Lomonosov Ridge, so I am quite sure that there have been more recent
open Arctic events than Barber says, Best wishes Peter
On Jul 24 2010, John Nissen wrote:
Hi again,
I've always wondered whether there has been a seasonably ice-free
Arctic Ocean in recent interglacial periods, and an answer (no) came
in a plenary lecture at the International Polar Year Oslo Science
Conference in June by Professor David Barber, about 21 minutes into
his talk:
http://video.hint.no/mmt201v10/osc/?vid=55
He says he has "downcast" his forecast for a seasonably ice free
Arctic to between 2013 and 2030. Then he says it's a long time since
there's been a seaonsably ice free Arctic, and "one can debate
whether that's 1 million years or 14 million years."
During the next minutes he describes how they discovered thin, rotten
ice where there was supposed to be multi-year ice. So satellite data
cannot always be trusted!
At 40 minutes he comes to something that's new to me: that CO2 is an
important part of the sea ice formation process. He even likens the
sea ice to a rain forest!
Later on, around 45 minutes, he discusses the importance of opinions
of Inuit peoples and how they see the effect of global warming in
their daily lives.
So there's lots of interesting stuff about the sea ice - but there's
nothing about what we should do about its decline. His conclusion -
just continue research for another decade.
Cheers,
John
---
John Nissen wrote:
Hi all,
Here's a posting on Climate Progress that I missed in June:
http://climateprogress.org/2010/06/06/arctic-death-spiral-maslowski-ice-free-arctic-watts-goddard-wattsupwiththat/#more-26815
This refers (1) to a presentation by Maslowski here:
http://soa.arcus.org/sites/soa.arcus.org/files/sessions/1-1-advances-understanding-arctic-system-components/pdf/1-1-7-maslowski-wieslaw.pdf
and (2) to a study by a team from Ohio State University:
http://researchnews.osu.edu/archive/sedcore.htm
I wonder what the Hadley Centre make of this. Surely it lends
weight to the argument for urgent geoengineering to cool the Arctic
(and waters entering the Arctic) in order to try and prevent
inexorable deterioration of the situation towards catastrophic
methane release from permafrost and catastrophic sea level rise from
Greenland ice sheet disintegration.
Cheers,
John
--
You received this message because you are subscribed to the Google Groups
"geoengineering" group.
To post to this group, send email to [email protected].
To unsubscribe from this group, send email to
[email protected].
For more options, visit this group at
http://groups.google.com/group/geoengineering?hl=en.
