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Old September 5th 16, 09:07 PM posted to uk.sci.weather
Pete B[_4_] Pete B[_4_] is offline
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Default The sea Ice at the North Pole Loks precariously Thin and Open

"Graham P Davis" wrote in message
-jade...
On Sun, 4 Sep 2016 11:59:33 -0700 (PDT)
Alastair wrote:

On Sunday, 4 September 2016 19:30:14 UTC+1, Graham P Davis wrote:
On Sun, 4 Sep 2016 09:26:37 -0700 (PDT)
Alastair wrote:

On Saturday, September 3, 2016 at 11:35:16 PM UTC+1, Lawrence
Jenkins wrote:
http://www.britishpathe.com/video/at...-at-north-pole

That was the summer before the fabled winter of 1962/63

A bit like this year!

ftp://ftp-projects.zmaw.de/seaice/AM...R2_3.125km.png
http://ocean.dmi.dk/arctic/plots/mea...meanT_2016.png
https://sites.google.com/site/arctic...entration-maps
http://polar.ncep.noaa.gov/seaice/analysis/nh.xml
http://www.iup.uni-bremen.de:8084/am...2_previous.png

Yes, except that the extent of the ice this year at the moment is
half what it was in 1963.



Hi Graham,

Where can I see charts of the sea-ice before the satellite era,
especially 1962,3 & 4?


Those covering that era (August? 1959 to sometime in 1982?) were
produced by the Met Office and should be available at their
Library/Archive but the paper copies may have gone missing. I've asked
for copies (they used to cost 3/6d!) but have been told that I can only
see them by visiting Exeter. If I'd known how important they'd become
I would've kept copies during the time I was producing them.

The Met Office started production of Arctic Ice charts after the
Danish Met Institute end theirs. Their entire production (1893-1956) is
online he http://brunnur.vedur.is/pub/trausti/. The charts are at
the bottom of the page, either as jpg or pdf.

In the absence of easily-available charts for 1963, I used the following
graph to compare 2007 with 1963:
http://arctic.atmos.uiuc.edu/cryosph....1900-2010.png
I used 2007 because this year has just overtaken that year to be in
second place behind 2012.

--
Graham P Davis, Bracknell, Berks. [Retd meteorologist/programmer]
http://www.scarlet-jade.com/
I wear the cheese. It does not wear me.
Posted with Claws: http://www.claws-mail.org/




I found that seasonal extent chart very interesting. I have seen it before
but not studied it in as much detail as now. Looking at the summer changes
in particular, it would appear that the decline in summer ice extent began
as far back as the early 1950's with the more significant decline from
around 1970 onward. Experts may correct me but to me, the summer decline is
the most important as that removes a bulk of the older, thicker multiyear
ice. If 2012 was on there, then the last decades decline would look even
worse.

How was extent measured in detail before the current satellite era, i.e.
1979 onward according to sites such as NSIDC and the UIUC Cryosphere site?

--
Pete

Malvern Wells, S Worcs, 111m asl.

Please take my dog out twice to e-mail

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