On 29/01/2017 08:54, JohnD wrote:
"John Hall" wrote in message ...

If the amount of Arctic sea ice is reducing in JANUARY, even if it turns
out to be only for a day or two, that seems remarkable and really brings
it home just how far global warming has gone.
======================

This is for extent, which AIUI is more liable to error, as a parameter
rather than area but interesting nonetheless. But if you look at the
NSIDC extent chart at:

http://nsidc.org/arcticseaicenews/

you'll see that there was a also a brief net melt in November 2016 and
certainly a stall if not a technical dip in December and again in
mid-January.

What seems to be concerning the experts more than the relatively low
current area/extent values is that a substantial proportion of the
arctic ice is thin; while this will certainly still contribute to the
area/extent values as if it were traditional thicker ice, it will also
be easier to melt out once the spring/summer thaw starts in earnest. So
arctic ice _volume_ is potentially a more interesting parameter, though
one tricky to estimate and not updated publicly on a daily basis AFAIK.
So it will be interesting to see the PIOMAS end-January volume estimate
when it hopefully gets released in around a week's time.

The local retired polar oceanographer, living near me, seems to be most
concerned about the lack of multiyear ice in the Arctic, ie lack of
structural integrity.

The lack of Antarctic sea-ice area is before Larsen C breaks off