On Tuesday, 31 July 2018 08:40:00 UTC+1, N_Cook wrote:
global sea-ice

https://sites.google.com/site/arctis...t_byyear_b.png

is returning to on-this-day-of-the-year record minimum.
Will an upswing return in September is the next waypoint I suppose

Presumably just curious,never having seen this before, rather than any
significance, going to source

http://nsidc.org/arcticseaicenews/ch...sea-ice-graph/

and selecting 2017 N & S poles, both at mimimum arctic and minimum
antarctic sea-ice, near enough on 29 July of all (satellite era) years
Global sea ice
2017, 23.356 million sq km
2018, 23.391 " "

There is a chart he http://web.nersc.no/WebData/arctic-r...1_ice_area.png which shows ice area rather than extent. The ice there is not on a minimum for time of year. Not sure why.

On 31/07/2018 11:36, Alastair wrote:

There is a chart he
http://web.nersc.no/WebData/arctic-r...1_ice_area.png
which shows ice area rather than extent. The ice there is not on a
minimum for time of year. Not sure why.


Simply because ice area and ice extent are different measures and they
never agree exactly. See eg:

http://nsidc.org/arcticseaicenews/faq/#area_extent

The chart corresponding to the area rather than the extent referred to
above is:

https://sites.google.com/site/arctis...a_byyear_b.png

(which really could do with some editing to clarify the colours - there
are now just too many superimposed lines).

On 31/07/2018 11:53, JGD wrote:
On 31/07/2018 11:36, Alastair wrote:

There is a chart he
http://web.nersc.no/WebData/arctic-r...1_ice_area.png
which shows ice area rather than extent. The ice there is not on a
minimum for time of year. Not sure why.


Simply because ice area and ice extent are different measures and they
never agree exactly. See eg:

http://nsidc.org/arcticseaicenews/faq/#area_extent

The chart corresponding to the area rather than the extent referred to
above is:

https://sites.google.com/site/arctis...a_byyear_b.png


(which really could do with some editing to clarify the colours - there
are now just too many superimposed lines).

On the other hand it does dramatically show the recent lines have not
the slightest inclination to return to the 4 decade 2 Standard Deviation
zone.
I did once go into a graphics package and use find and replace with
white to get some idea of one year's trace, then use Charctic where
there was a lot of overprint.

On Tuesday, 31 July 2018 11:53:14 UTC+1, JGD wrote:
On 31/07/2018 11:36, Alastair wrote:

There is a chart he
http://web.nersc.no/WebData/arctic-r...1_ice_area.png
which shows ice area rather than extent. The ice there is not on a
minimum for time of year. Not sure why.


Simply because ice area and ice extent are different measures and they
never agree exactly. See eg:

http://nsidc.org/arcticseaicenews/faq/#area_extent

The chart corresponding to the area rather than the extent referred to
above is:

https://sites.google.com/site/arctis...a_byyear_b.png

(which really could do with some editing to clarify the colours - there
are now just too many superimposed lines).

The area chart shows this year as the most ice over the last few years whereas the extent chart is showing the least ice cover the last few years. It is this contrast that I find curious.

On 31/07/2018 15:05, Alastair wrote:
On Tuesday, 31 July 2018 11:53:14 UTC+1, JGD wrote:
On 31/07/2018 11:36, Alastair wrote:

There is a chart he
http://web.nersc.no/WebData/arctic-r...1_ice_area.png
which shows ice area rather than extent. The ice there is not on a
minimum for time of year. Not sure why.


Simply because ice area and ice extent are different measures and they
never agree exactly. See eg:

http://nsidc.org/arcticseaicenews/faq/#area_extent

The chart corresponding to the area rather than the extent referred to
above is:

https://sites.google.com/site/arctis...a_byyear_b.png

(which really could do with some editing to clarify the colours - there
are now just too many superimposed lines).

The area chart shows this year as the most ice over the last few years whereas the extent chart is showing the least ice cover the last few years. It is this contrast that I find curious.


What is dashed red ,unfiltered 2018, on

http://nsidc.org/arcticseaicenews/faq/#area_extent

This plot has been revised substantially / erroneously? in the last day

https://sites.google.com/site/arctis...a_byyear_b.png

On 31/07/2018 18:45, N_Cook wrote:
This plot has been revised substantially / erroneously? in the last day

https://sites.google.com/site/arctis...a_byyear_b.png


It looks like NSIDC has crapped-out, Charctic is stuck on 29 July
output. Like www tide-gauges around the country, just as sea-levels get
interesting in a stormv they tend to crap-out (last time locally last
Sunday with a surge going along the channel),perhaps Trump pulled the plug.

Then perhaps the "byyear" auto aggregator received some default
erroneous values for 30 July update.

On 01/08/2018 09:14, N_Cook wrote:

It looks like NSIDC has crapped-out, Charctic is stuck on 29 July
output.

I can see Charctic for 30th July at 6.918M sqkm, which looks as
expected. 31st July not there yet, but maybe this afternoon?

On 01/08/2018 11:21, JGD wrote:
On 01/08/2018 09:14, N_Cook wrote:

It looks like NSIDC has crapped-out, Charctic is stuck on 29 July output.

I can see Charctic for 30th July at 6.918M sqkm, which looks as
expected. 31st July not there yet, but maybe this afternoon?


Something cleared thru later this morning and Charctic got updated for
30 July and return to extent-wise on-the-day global sea-ice record
minimum again
2017 previous minimum (30 July) 23.372
2018 23.351
so less by 21,000 sq km

31 July would usually output after 13:00 BSt today
the byyear site is offline as of posting this, was up 10 muinutes ago.

On 01/08/2018 12:36, N_Cook wrote:

31 July would usually output after 13:00 BSt today

Yes, it's there now with the profile still continuing a reasonably steep
that, though still 0.3Msqkm above the 2012 curve.

Of more interest perhaps for now is the latest UAH global temperature
figure for July which is on the rise again at +0.32C.