On Aug 15, 9:34*am, "Will Hand" wrote:
"Graham P Davis" wrote in ...





Will Hand wrote:

"Graham P Davis" wrote in message
...
James Brown wrote:

http://news.bbc.co.uk/1/hi/sci/tech/8200680.stm

I'm wondering if this is purely a byproduct of GW or why it should be
accelerating - given Antarctic SST's fairly stable etc.

I think the Antarctic SST's are stable - or even have been lower than
normal
- because the excess melting of of the land ice has provided a larger
supply
of cold, fresh water than normal.

Graham, am I correct to say that the ocean flow round Antartica is
largely
decoupled from the rest of the planet?

Not something I know too much about but, after some googling, I'd say no.
For instance, see
http://oceanworld.tamu.edu/resources...ter13/chapter1...

Thanks Graham,

*quoteThe Antarctic Circumpolar Current is an important feature of the
ocean's deep circulation because it transports deep and intermediate water
between the Atlantic, Indian, and Pacific Ocean, and because it contributes
to the deep circulation in all basins. /quote

So, what goes on in the Antarctic *is* important for the planet. Paul, Is
this the explanation you were hoping Lawarence would have provided? OK we
can argue about it but I am not an expert on complicated interactions
between ocean and atmosphere, which is why I have kept quiet.
Also, I would certainly never go as far to say that - just because the
Antartic is stable or getting colder it means GW is going away, it is far
more complex than that.

Cheers,

Will
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I think Alistair is on the right lines and your own summary captures
the difficulties of interpretation. Graham may well be right too!

Personally, I think that problem here is the lack of data in terms of
observations, both on land and over sea and in terms of ice changes
over time.

The GW difficulty is that warmer temperatures, especially in the
oceans, should produce more melting around the fringes of the
continent. On the other hand warmer temperatures in the atmosphere may
produce more precipitation, thus adding to the glacier inputs. Maybe
the research by Prof Wingham, showing thinning of the Pine Island
glacier indicates something, but why is that glacier losing mass? Is
if from less snowfall, or more ablation? In addition, is the Pine
Island glacier typical of all Antarctic glaciers, or even typical of
that area?

Are increasing ocean temps responsible for melting at the Antarctic
fringes? ocean An Australian study in 2008 came to the conclusion that
sea level rises around Antarctica were due to warming oceans, not ice
melting (both could be due to GW, of course):

http://www.abc.net.au/science/articl...18/2165549.htm

This adds to the difficulties as well; a study by the BAS showed that
increasing Antarctic sea ice could be due to the influence of the
Antarctic ozone hole:

http://www.antarctica.ac.uk/press/pr...ase.php?id=838

Zhang's paper from 2007, concludes that increasing Antarctic sea ice
in a warming climate could be due to a reduction in upward heat
transfer, but also recognises that there could be other mechanisms.

http://psc.apl.washington.edu/zhang/...20-11-2515.pdf

The overall need is for more research.

The answer to your question, of course, is that I have no idea what
Lawrence would have said, but how anyone can assert that increasing
Antarctic sea ice could be used as a support to an argument about GW
having finished, just doesn't understand the complexity of drawing
conclusions from either the present ice amount, or the trend over
time.

So few researchers, so few measurements combined with a regional
approach = a great lack of surety as to exactly how Antarctic sea ice
will react to GW.