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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1100 on: January 20, 2019, 03:23:39 PM »
Interesting new paper about the role that atmosphere and ocean have played in the reduction of Antarctic sea ice since 2016:

Meehl et al., 
"Sustained ocean changes contributed to sudden Antarctic sea ice retreat in late 2016"

https://www.nature.com/articles/s41467-018-07865-9

Great stuff, Steven. Been waiting for a paper like this for ages. And open access - I downloaded the pdf pdq.

One quibble (as always)- the paper does not speculate whether these new conditions in the southern ocean are likely to continue or may be temporary. But all I have to do is watch and wait a few more years?
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1101 on: January 21, 2019, 11:55:52 AM »
JAXA ANTARCTIC Sea Ice Extent : 3,381,298 km2(January 20, 2019)

Extent loss of 57k , 50 k less than the average for this day.

Extent is 2nd lowest in the satellite record for this day.
Extent loss from maximum is 280k km2 (1.9%) greater than the 10 year average so far, with on average 90.1% of extent loss for the season done and on average 30 days to minimum.

The average remaining melt from this day to minimum would produce a minimum of 1.79 million km2,  360k km2 less than the record low in 2017.  Most of the remaining ice is at high concentration. With low concentration ice mostly gone the remaining solid ice close to the coast will likely continue to slow melt down further to a crawl.

Nevertheless, a record low minimum, the first below 2 million km2, is still my guess for the 2019 minimum, continuing the loss of Antarctic sea ice over the last three years (currently 3.1 million km2 less than the record high in 2014-15). However, the drop in daily extent losses has considerably reduced confidence in that prediction.
"Para a Causa do Povo a Luta Continua!"
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Gray-Wolf

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Re: Sea Ice Extent around Antarctica
« Reply #1102 on: January 21, 2019, 02:52:21 PM »
Hi gerontocrat!
My take on the sudden turn around in extent/area around Antarctica was always a two pronged assault with both ocean/surface and upper trop/strat boundaries in play?

The upper atmospheric level was tied into the forcings that low ozone placed there and the ocean/atmosphere was a matter of 'tweaked' Naturals ( Tweaked by the asian dimming since the early 90's)

So are the changes temporary or for good?

Well .for me, a bit of both!

The Ozone hole will ( hopefully ) continue to mend and so that portion of the forcing that brought about that 1% increase in extent per decade is now ending.

The flip of the naturals will surely flip back at some point but ,again, the portion that was driven by asian dimming is now also passed its maximum impact as China forges ahead with its clean air initiatives?

As such I now expect us to rapidly catch up with the modelled losses we saw in the 80's/90's with the 'odd' exceptional year of ice growth in among the steady drops.

To me the issue has to be the ability of the ice to transfer swells to the coasts/shelfs behind? In the Arctic ships have witnessed 1m ice put up no obstacle to swells passing through it so will the same apply in the Southern Ocean?

If shelfs now have to face year round 'waggling' from wave and tide it must take more of a toll on them than a 3 or 4 month window of waggling does?
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1103 on: January 21, 2019, 03:24:15 PM »
Hi Gray-Wolf.

Will China continue to clean up its industrial pollution?
Will China continue to push renewables and EVs?

Will India modify its "smokestack of the world" industrial policy?
Will India continue to push renewables and get aboard with EVs?

Will the natural oscillations in wind and ocean currents accelerate or reverse sea ice and ice shelf melt?

etc etc etc

My money is on insolation (less pollution) and AGW (CO2 ppm continues up)  forcing melt - sea ice, ice shelves, coastal glaciers. But like all good jokes - timing?



"Para a Causa do Povo a Luta Continua!"
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1104 on: January 22, 2019, 11:51:10 AM »
JAXA ANTARCTIC Sea Ice Extent : 3,323,557 km2(January 21, 2019)

Extent loss of 58k , 49 k less than the average for this day.

Extent is 2nd lowest in the satellite record for this day.
Extent loss from maximum is 235k km2 (1.6%) greater than the 10 year average so far, with on average 90.7% of extent loss for the season done and on average 29 days to minimum.

The average remaining melt from this day to minimum would produce a minimum of 1.84 million km2,  310k km2 less than the record low in 2017.  Most of the remaining ice is at high concentration. With low concentration ice mostly gone the remaining solid ice close to the coast will likely continue to slow melt down further to a crawl.

Nevertheless, a record low minimum, the first below 2 million km2, is still my guess for the 2019 minimum, continuing the loss of Antarctic sea ice over the last three years (currently 3.1 million km2 less than the record high in 2014-15). However, the drop in daily extent losses has considerably reduced confidence in that prediction (again).
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
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oren

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Re: Sea Ice Extent around Antarctica
« Reply #1105 on: January 22, 2019, 01:20:59 PM »
The big advantage of this year vs. the previous two has been a huge lead in the Ross sea sector that developed in mid-Dec. Recently this lead has completely evaporated. In the largest sector, the Weddel Sea, all three years are in lockstep.
It still leading slightly in the West Pacific sector, but lagging in the Amundsen-Bellingshausen sector. All in all, I don't expect a significant new record minimum at this time, barring big surprises. I see a higher probability for a 2nd or even 3rd place finish, due to the resilience in the Amundsen/Bellingshausen.
The attached charts are for AMSR2 area, courtesy of Wipneus, but I expect similar behavior in other metrics. I prefer AMSR2 area as I see it as the best and most accurate leading indicator.

gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1106 on: January 23, 2019, 08:41:05 AM »
JAXA ANTARCTIC Sea Ice Extent : 3,323,557 km2(January 21, 2019)

Extent loss of 43k , 60 k less than the average for this day.

Extent is 3rd lowest in the satellite record for this day, behind 2017 and 2006.
Extent loss from maximum is 172k km2 (1.2%) greater than the 10 year average so far, with on average 91.4% of extent loss for the season done and on average 28 days to minimum.

The average remaining melt from this day to minimum would produce a minimum of 1.90 million km2,  250k km2 less than the record low in 2017.  Most of the remaining ice is at high concentration. With low concentration ice mostly gone the remaining solid ice close to the coast will likely continue to slow melt down further to a crawl.

The drop in daily extent losses has evaporated my confidence in a new record low to approaching zero.
"Para a Causa do Povo a Luta Continua!"
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Often Distant

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Re: Sea Ice Extent around Antarctica
« Reply #1107 on: January 23, 2019, 10:50:37 AM »
One could gauge a rough sense of the thickness of that ice calving away from Pine Island glacier.


gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1108 on: January 24, 2019, 07:05:26 AM »
JAXA ANTARCTIC Sea Ice Extent : 3,225,391 km2(January 23, 2019)

Extent loss of 55k , 32 k less than the average for this day.

Extent is 3rd lowest in the satellite record for this day, behind 2017 and 2006.
Extent loss from maximum is 144k km2 (1.0%) greater than the 10 year average so far, with on average 91.9% of extent loss for the season done and on average 27 days to minimum.

The average remaining melt from this day to minimum would produce a minimum of 1.93 million km2,  220k km2 less than the record low in 2017.  Most of the remaining ice is at high concentration. With low concentration ice mostly gone the remaining solid ice close to the coast will likely continue to slow melt down further to a crawl.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1109 on: January 25, 2019, 08:45:12 AM »
JAXA ANTARCTIC Sea Ice Extent : 3,190,564 km2(January 24, 2019)

Extent loss of 35k , 43 k less than the average for this day.

Extent is 3rd lowest in the satellite record for this day, behind 2017 and 2006.
Extent loss from maximum is 97k km2 (0.7%) greater than the 10 year average so far, with on average 92.4% of extent loss for the season done and on average 26 days to minimum.

The average remaining melt from this day to minimum would produce a minimum of 1.97 million km2,  170k km2 less than the record low in 2017.  Most of the remaining ice is at high concentration. With low concentration ice mostly gone the remaining solid ice close to the coast melt has been below average every day for nearly a month and has now slowed down further to a crawl.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1110 on: January 26, 2019, 12:47:10 PM »
JAXA ANTARCTIC Sea Ice Extent : 3,160,645 km2(January 25, 2019)

Extent loss of 30k , 55 k less than the average for this day.

Extent is 4th lowest in the satellite record for this day, behind 2018, 2017, and 2006.
Extent loss from maximum is 41k km2 (0.3%) greater than the 10 year average so far, with on average 92.9% of extent loss for the season done and on average 25 days to minimum (19th February).

The average remaining melt from this day to minimum would produce a minimum of 2.03 million km2, 170k km2 less than the record low in 2017.  Most of the remaining ice is at high concentration. With low concentration ice mostly gone the remaining solid ice close to the coast melt has been below average every day for nearly a month and has now slowed down further to a crawl.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
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Shared Humanity

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Re: Sea Ice Extent around Antarctica
« Reply #1111 on: January 26, 2019, 04:34:05 PM »
Could easily finish in 5th place.

gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1112 on: January 26, 2019, 05:38:58 PM »
Here are some graphs based on NSIDC data downoaded from  https://sites.google.com/site/arctischepinguin/home/sea-ice-extent-area/data
(file nsidc_ant_nt_detail.txt)

Firstly Total Antarctic Graphs, as usual disguising considerable variations between the various parts of the southern ocean sea ice.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1113 on: January 26, 2019, 05:56:41 PM »
Here are some graphs based on NSIDC data downloaded from  https://sites.google.com/site/arctischepinguin/home/sea-ice-extent-area/data
(file nsidc_ant_nt_detail.txt)

Weddell Sea. Look how minimum sea ice was increasing decade by decade and reversed from 2016. Area at 25 Jan 2019 has just gone above the 1980's area. Reversal of recent trend?
"Para a Causa do Povo a Luta Continua!"
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1114 on: January 26, 2019, 06:15:42 PM »
Here are some graphs based on NSIDC data downloaded from  https://sites.google.com/site/arctischepinguin/home/sea-ice-extent-area/data
(file nsidc_ant_nt_detail.txt)

BellingHausen & Amundsen Sea Ice. In contrast to the Weddell Sea, minimum sea ice was decreasing decade by decade. Area and extent in 2018-19 recently has reversed this trend.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1115 on: January 26, 2019, 06:22:09 PM »
Here are some graphs based on NSIDC data downloaded from  https://sites.google.com/site/arctischepinguin/home/sea-ice-extent-area/data
(file nsidc_ant_nt_detail.txt)

Ross Sea Ice. The Ross Sea has shown the greatest reduction in minimum both over the decades and in recent years. 2019 minimum looks like it will be in line with 2017 and 2018.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1116 on: January 26, 2019, 06:29:14 PM »
Here are some graphs based on NSIDC data downloaded from  https://sites.google.com/site/arctischepinguin/home/sea-ice-extent-area/data
(file nsidc_ant_nt_detail.txt)

"West Pacific" minimum Sea Ice has trended upwards over the decades. The 2018-19 year looks like it will partly reverse this decadal trend.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1117 on: January 26, 2019, 06:38:18 PM »
Here are some graphs based on NSIDC data downloaded from  https://sites.google.com/site/arctischepinguin/home/sea-ice-extent-area/data
(file nsidc_ant_nt_detail.txt)

"Indian Ocean" minimum Sea Ice has trended upwards over the decades. The 2018-19 year looks like it will continue this decadal trend.


ps:- So grateful to Mister Artische Pinguin for those files stored away on the ASIF files. But I will have a quibble to maintain the grumpy old man" credentials. I wish the file was in .csv format instead of .txt . (I now use a package called Libre Office, almost as good as Microsoft Office and freeeeee. 2019 project is to dump Microsfoft, Google etc completely )
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1118 on: January 27, 2019, 06:30:04 AM »
JAXA ANTARCTIC Sea Ice Extent : 3,109,024 km2(January 26, 2019)

Extent loss of 52k , 26 k less than the average for this day.

Extent is 4th lowest in the satellite record for this day, behind 2018, 2017, and 2006.
Extent loss from maximum is 11k km2 (0.1%) greater than the 10 year average so far, with on average 93.4% of extent loss for the season done and on average 24 days to minimum (19th February).

The average remaining melt from this day to minimum would produce a minimum of 2.05 million km2, 100k km2 less than the record low in 2017.  Most of the remaining ice is at high concentration. With low concentration ice mostly gone the remaining solid ice close to the coast melt has been below average every day for a month.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

Stephan

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Re: Sea Ice Extent around Antarctica
« Reply #1119 on: January 27, 2019, 09:38:35 AM »
JAXA ANTARCTIC Sea Ice Extent : 3,109,024 km2(January 26, 2019)

[...]
The average remaining melt from this day to minimum would produce a minimum of 2.05 million km2, 100k km2 less than the record low in 2017.  Most of the remaining ice is at high concentration. With low concentration ice mostly gone the remaining solid ice close to the coast melt has been below average every day for a month.
If Feb 2019 minimum "wants" to become a record minimum the daily losses must be greater than average for the next three weeks. Otherwise this year's minimum will end up fourth to seventh -- and if the very crawly decrease continues even a higher place in the ranking is possible...

gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1120 on: January 28, 2019, 11:31:41 AM »
JAXA ANTARCTIC Sea Ice Extent : 3,054,285 km2(January 27, 2019)

Extent loss of 55k , 21 k less than the average for this day.

Extent is 4th lowest in the satellite record for this day, behind 2018, 2017, and 2006.
Extent loss from maximum is 2k km2 (0.0%) less than the 10 year average so far, with on average 93.9% of extent loss for the season done and on average 23 days to minimum (19th February).

The average remaining melt from this day to minimum would produce a minimum of 2.07 million km2, 80k km2 less than the record low in 2017.  Most of the remaining ice is at high concentration. With low concentration ice mostly gone the remaining solid ice close to the coast melt has been below average every day for over a month.
"Para a Causa do Povo a Luta Continua!"
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wdmn

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Re: Sea Ice Extent around Antarctica
« Reply #1121 on: January 28, 2019, 05:16:37 PM »
Is there volume data for Antarctic sea ice?

gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1122 on: January 28, 2019, 06:20:54 PM »
Is there volume data for Antarctic sea ice?
As far as I know, there is no consistent measurement system as in the Arctic (PIOMAS from the Polar Science Center).

As far as I know, this is because apart from land fast ice at the coast (2-3 million km2 ?), just about all Antarctic sea ice forms during the Austral winter and melts during the Austral summer. i.e. relatively thin (much harder to measure) and temporary.

ps: The new Icesat-2 measures stuff at far finer resolution in all 3 dimensions than anything before. Perhaps someone will think of setting up a data collection and analysis system for Antarctic Sea Ice as a by-product of measuring the ice-shelves, glaciers and ice sheet. You never know.
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wdmn

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Re: Sea Ice Extent around Antarctica
« Reply #1123 on: January 28, 2019, 09:16:04 PM »
Thank you gerontocrat.

My thought was that precisely because the fast ice around Antarctic is less variable in terms of area and extent, that we might learn more about it and just how things are changing year/year by looking at its volume.

« Last Edit: January 29, 2019, 05:46:55 AM by wdmn »

oren

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Re: Sea Ice Extent around Antarctica
« Reply #1124 on: January 29, 2019, 04:02:20 AM »
Is there volume data for Antarctic sea ice?
Yes there is. As usual, Wipneus comes to the rescue.
https://sites.google.com/site/arctischepinguin/home/giomas
GIOMAS Antarctic Sea Ice Volume. Prepared by Wipneus
Data: GIOMAS http://psc.apl.washington.edu/zhang/Global_seaice/

It seems the volume charts on ArctischePinguin are only updated to mid-2017, but I think the data itself is still generated by GIOMAS.

wdmn

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Re: Sea Ice Extent around Antarctica
« Reply #1125 on: January 29, 2019, 06:01:16 AM »
Thanks oren.

Too bad the data stops (I think thickness only goes up to 2016 even in Zhang's files). I would like to see 2016 to present: how much has volume declined during the years that extent has declined, and what is going on this year?


gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1126 on: January 29, 2019, 01:05:56 PM »
JAXA ANTARCTIC Sea Ice Extent : 3,010,429 km2(January 28, 2019)

Extent loss of 44k , 26 k less than the average for this day.

Extent is 4th lowest in the satellite record for this day, behind 2018, 2017, and 2006.
Extent loss from maximum is 31k km2 (0.6%) less than the 10 year average so far, with on average 94.3% of extent loss for the season done and on average 22 days to minimum (19th February).

The average remaining melt from this day to minimum would produce a minimum of 2.10 million km2, 50k km2 less than the record low in 2017.  Most of the remaining ice is at high concentration. With low concentration ice mostly gone the remaining solid ice close to the coast melt has been below average every day for over a month.
"Para a Causa do Povo a Luta Continua!"
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1127 on: January 30, 2019, 08:50:13 AM »
JAXA ANTARCTIC Sea Ice Extent : 2,980,080 km2(January 29, 2019)

Extent loss of 30k , 35 k less than the average for this day.

Extent is 4th lowest in the satellite record for this day, behind 2018, 2017, and 2006.
Extent loss from maximum is 67k km2 (0.4%) less than the 10 year average so far, with on average 94.7% of extent loss for the season done and on average 21 days to minimum (19th February).

The average remaining melt from this day to minimum would produce a minimum of 2.14 million km2, 10k km2 less than the record low in 2017.  Most of the remaining ice is at high concentration. With low concentration ice mostly gone the remaining solid ice close to the coast melt has been below average every day for over a month. If this continues, this suggests a somewhat higher maximum - 2.4 million km2?
"Para a Causa do Povo a Luta Continua!"
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1128 on: February 01, 2019, 11:58:12 AM »
JAXA ANTARCTIC Sea Ice Extent : 2,918,378 km2(January 31, 2019)

Extent loss of 33k, 24k less than the average for this day.

Extent is 5th lowest in the satellite record for this day, behind 2018, 2017, 2011, and 2006.
Extent loss from maximum is 133k km2 (0.9%) less than the 10 year average so far, with on average 95.5% of extent loss for the season done and on average 19 days to minimum (19th February).

The average remaining melt from this day to minimum would produce a minimum of 2.20 million km2, 50k km2 more than the record low in 2017.  Most of the remaining ice is at high concentration. With low concentration ice mostly gone the remaining solid ice close to the coast melt has been below average every day for over a month. If this continues, this suggests a somewhat higher maximum - 2.4 million km2 or even a lot more.
« Last Edit: February 02, 2019, 08:55:02 AM by gerontocrat »
"Para a Causa do Povo a Luta Continua!"
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FredBear

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Re: Sea Ice Extent around Antarctica
« Reply #1129 on: February 01, 2019, 11:04:04 PM »
I think new-forming sea ice is blowing northwards onto the backside of the old floes at the southern edge of the Weddell Sea today - Freeze-up started? (From   arctic.io  )

gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1130 on: February 02, 2019, 08:48:42 AM »
JAXA ANTARCTIC Sea Ice Extent : 2,905,530 km2(February 1, 2019)

Extent loss of 13k, 33k less than the average for this day.

Extent is 5th lowest in the satellite record for this day, behind 2018, 2017, 2011, and 2006.
Extent loss from maximum is 159k km2 (1.0%) less than the 10 year average so far, with on average 95.8% of extent loss for the season done and on average 18 days to minimum (19th February).

The Perils of Projections
The average remaining melt from this day to minimum would produce a minimum of 2.23 million km2, 90k km2 more than the record low in 2017. 

Most of the remaining ice is at high concentration. With low concentration ice mostly gone, the remaining ice being solid and close to the coast, melt has been below average every day for over a month. If this continues, this suggests a somewhat higher maximum - 2.4 million km2 or even a lot more. Indeed, a simple linear projection of 2019 trends in melt gives a remaining melt to minimum of less than 100,000 km2, resulting in a minimum of more than 2.8 million km2.
"Para a Causa do Povo a Luta Continua!"
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1131 on: February 02, 2019, 05:53:57 PM »
Once again graphs using NSIDC data from wipneus via file nsidc_ant_nt_detail.txt from https://sites.google.com/site/arctischepinguin/home/sea-ice-extent-area/data
as at 1st February 2019


Total Antarctic area and extent basically stalled.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1132 on: February 02, 2019, 05:58:56 PM »
Once again graphs using NSIDC data from wipneus via file nsidc_ant_nt_detail.txt from https://sites.google.com/site/arctischepinguin/home/sea-ice-extent-area/data
as at 1st February 2019


Weddell Sea area and extent basically stalled. But concentration well below last 2 years and 2010s average so still vulnerable to further melt.
"Para a Causa do Povo a Luta Continua!"
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1133 on: February 02, 2019, 06:08:50 PM »
Once again graphs using NSIDC data from wipneus via file nsidc_ant_nt_detail.txt from https://sites.google.com/site/arctischepinguin/home/sea-ice-extent-area/data
as at 1st February 2019


Bellingshausen & Amundsen Sea area and extent basically stalled.
"Para a Causa do Povo a Luta Continua!"
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1134 on: February 02, 2019, 06:17:40 PM »
Once again graphs using NSIDC data from wipneus via file nsidc_ant_nt_detail.txt from https://sites.google.com/site/arctischepinguin/home/sea-ice-extent-area/data
as at 1st February 2019


Ross Sea area and extent basically stalled. Concentration going up suggesting not a lot more melt possible.
"Para a Causa do Povo a Luta Continua!"
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1135 on: February 02, 2019, 06:21:17 PM »
Once again graphs using NSIDC data from wipneus via file nsidc_ant_nt_detail.txt from https://sites.google.com/site/arctischepinguin/home/sea-ice-extent-area/data
as at 1st February 2019


West Pacific Sector Sea area and extent basically stalled.
"Para a Causa do Povo a Luta Continua!"
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1136 on: February 02, 2019, 06:29:44 PM »
Once again graphs using NSIDC data from wipneus via file nsidc_ant_nt_detail.txt from https://sites.google.com/site/arctischepinguin/home/sea-ice-extent-area/data
as at 1st February 2019


Indian Ocean Sector Sector Sea area and extent basically stalled. Concentration really high. Resistant to melt.


Conclusion after all that work ? Should have gone one or two bins higher in the January Poll
"Para a Causa do Povo a Luta Continua!"
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1137 on: February 03, 2019, 05:26:53 AM »
JAXA ANTARCTIC Sea Ice Extent : 2,890,921 km2(February 2, 2019)

Extent loss of 15k, 39k less than the average for this day.

Extent is 5th lowest in the satellite record for this day, behind 2018, 2017, 2011, and 2006.
Extent loss from maximum is 204k km2 (1.3%) less than the 10 year average so far, with on average 96.1% of extent loss for the season done and on average 17 days to minimum (19th February).

The Perils of Projections
The average remaining melt from this day to minimum would produce a minimum of 2.27 million km2, 120k km2 more than the record low in 2017. 

Most of the remaining ice is at high concentration. With low concentration ice mostly gone, the remaining ice being solid and close to the coast, melt has been below average every day for over a month. If this continues, this suggests a somewhat higher maximum of around 2.5 million km2 or even more. Indeed, a simple linear projection of 2019 trends in melt gives a remaining melt to minimum of less than 100,000 km2, resulting in a minimum of more than 2.8 million km2.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

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Re: Sea Ice Extent around Antarctica
« Reply #1138 on: February 03, 2019, 09:03:42 AM »
Thank you for this comprehensive information. But I still think that there is some more ice to melt and the less than average melt will slightly turn into an average or even an above average melt in the next three weeks.

gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1139 on: February 04, 2019, 09:20:28 AM »
JAXA ANTARCTIC Sea Ice Extent : 2,868,686 km2(February 3, 2019)

Extent loss of 22k, 34k less than the average of 56k for this day.

Extent is 5th lowest in the satellite record for this day, behind 2018, 2017, 2011, and 2006.
Extent loss from maximum is 238k km2 (1.5%) less than the 10 year average so far, with on average 96.5% of extent loss for the season done and on average 16 days to minimum (19th February).

The Perils of Projections
The average remaining melt from this day to minimum would produce a minimum of 2.31 million km2, 160k km2 more than the record low in 2017.  Using the average remaining melt from this day to minimum of the 2016 to 2018 years would give a minimum of 2.52 million km2.

Most of the remaining ice is at high concentration. With low concentration ice mostly gone, the remaining ice being solid and close to the coast, melt has been below average every day for over a month. Indeed, a simple linear projection of recent 2019 trends in melt gives a remaining melt to minimum of less than 100,000 km2, resulting in a minimum of 2.8 million km2 on the 10th February.
[/quote]
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
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Often Distant

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Re: Sea Ice Extent around Antarctica
« Reply #1140 on: February 05, 2019, 06:22:09 AM »
Watching for potential break up of Ross ice shelf. Seems not to be this year. Quite early for a freeze up though. Could yet melt out back to where it was.

gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1141 on: February 05, 2019, 08:05:42 AM »
JAXA ANTARCTIC Sea Ice Extent : 2,835,088 km2(February 4, 2019)

Extent loss of 34k, 25k less than the average of 59k for this day.

Extent is 5th lowest in the satellite record for this day, behind 2018, 2017, 2011, and 2006.
Extent loss from maximum is 259k km2 (1.7%) less than the 10 year average so far, with on average 96.9% of extent loss for the season done and on average 15 days to minimum (19th February).

The Perils of Projections
The average remaining melt from this day to minimum would produce a minimum of 2.33 million km2, 180k km2 more than the record low in 2017.  Using the average remaining melt from this day to minimum of the 2016 to 2018 years would give a minimum of 2.53 million km2.

Most of the remaining ice is at high concentration. With low concentration ice mostly gone, the remaining ice being solid and close to the coast, melt has been below average every day for over a month. Indeed, a simple linear projection of recent 2019 trends in melt gives a remaining melt to minimum of less than 100,000 km2, resulting in a minimum of around 2.75 million km2 on the 12th February.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

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Re: Sea Ice Extent around Antarctica
« Reply #1142 on: February 06, 2019, 01:48:06 AM »
reply to often distant post #1140

I prefer polarview for viewing cracks in ice shelves and glaciers. Not all locations are available everyday but you might like it too.

https://www.polarview.aq/antarctic

The files are often about 50mb but you can zoom in quite a bit to the detail you want. This picture is Feb 4 2019.

gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1143 on: February 06, 2019, 09:44:09 AM »
JAXA ANTARCTIC Sea Ice Extent : 2,807,389 km2(February 5, 2019)

Extent loss of 28k, 26k less than the average of 54k for this day.

Extent is 5th lowest in the satellite record for this day, behind 2018, 2017, 2011, and 2006.
Extent loss from maximum is 281k km2 (1.8%) less than the 10 year average so far, with on average 97.2% of extent loss for the season done and on average 14 days to minimum (19th February).

The Perils of Projections
The average remaining melt from this day to minimum would produce a minimum of 2.36 million km2, 210k km2 more than the record low in 2017.  Using the average remaining melt from this day to minimum of the 2016 to 2018 years would give a minimum of 2.53 million km2.

Most of the remaining ice is at high concentration. With low concentration ice mostly gone, the remaining ice being solid and close to the coast, melt has been below average every day for over a month. Indeed, a simple linear projection of recent 2019 trends in melt gives a remaining melt to minimum of less than 100,000 km2, resulting in a minimum of around 2.7 to 2.75 million km2 on around the 12th February.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1144 on: February 07, 2019, 08:44:25 AM »
JAXA ANTARCTIC Sea Ice Extent : 2,795,854 km2(February 6, 2019)

Extent loss of 12k, 34k less than the average of 46k for this day.

Extent is 5th lowest in the satellite record for this day, behind 2018, 2017, 2011, and 2006.
Extent loss from maximum is 315k km2 (2.0%) less than the 10 year average so far, with on average 97.5% of extent loss for the season done and on average 13 days to minimum (19th February).

The Perils of Projections
The average remaining melt from this day to minimum would produce a minimum of 2.39 million km2, 240k km2 more than the record low in 2017.  Using the average remaining melt from this day to minimum of the 2016 to 2018 years would give a minimum of 2.55 million km2 400k km2 more than the record low in 2017.

Most of the remaining ice is at high concentration. With low concentration ice mostly gone, the remaining ice being solid and close to the coast, melt has been below average every day for over a month. Indeed, a simple linear projection of recent 2019 trends in melt gives a remaining melt to minimum of around 50,000 km2, resulting in a minimum of around 2.7 to 2.75 million km2 on around the 13th February.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1145 on: February 08, 2019, 09:52:52 AM »
JAXA ANTARCTIC Sea Ice Extent : 2,805,727 km2(February 7, 2019)

Extent GAIN of 10k, 55k less than the average LOSS of 45k for this day. Since the year 2000, only one other year had an extent gain this early - 2017 on this day and just 2k.

Extent is 7th lowest in the satellite record for this day, behind 2018, 2017, 2011, and 2006, and looking back further, 1997 and 1993. Table Ant3 only goes back to 2003. Damn.

Extent loss from maximum is 372k km2 (2.4%) less than the 10 year average so far, with on average 97.8% of extent loss for the season done and on average 12 days to minimum (19th February).

The Perils of Projections
The average remaining melt from this day to minimum would produce a minimum of 2.45 million km2, 300k km2 more than the record low in 2017.  Using the average remaining melt from this day to minimum of the 2016 to 2018 years would give a minimum of 2.59 million km2 440k km2 more than the record low in 2017.

Most of the remaining ice is at high concentration. With low concentration ice mostly gone, the remaining ice being solid and close to the coast, melt has been below average every day for approaching two months. Indeed, a simple linear projection of recent 2019 trends in melt gives a remaining melt to minimum of around 50,000 km2, resulting in a minimum of around  2.75 million km2  around the 10th February.
« Last Edit: February 08, 2019, 10:04:45 AM by gerontocrat »
"Para a Causa do Povo a Luta Continua!"
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Re: Sea Ice Extent around Antarctica
« Reply #1146 on: February 09, 2019, 10:03:42 AM »
JAXA ANTARCTIC Sea Ice Extent : 2,806,101 km2(February 8, 2019)

Extent GAIN of 0.4k, 45k less than the average LOSS of 45k for this day. Since the year 2000, only one other year had an extent gain this early - 2017 on this day and just 2k.

Extent is 7th lowest in the satellite record for this day, behind 2018, 2017, 2011, and 2006, and looking back further, 1997 and 1993. Table Ant3 only looks back to 2003.

Extent loss from maximum is 416k km2 (2.6%) less than the 10 year average so far, with on average 98.0% of extent loss for the season done and on average 11 days to minimum (19th February).

The Perils of Projections
The average remaining melt from this day to minimum would produce a minimum of 2.49 million km2, 340k km2 more than the record low in 2017.  Using the average remaining melt from this day to minimum of the 2016 to 2018 years would give a minimum of 2.62 million km2 470k km2 more than the record low in 2017.

Most of the remaining ice is at high concentration. With low concentration ice mostly gone, the remaining ice being solid and close to the coast, melt has been below average every day for well over one month. Indeed, a simple linear projection of recent 2019 trends in melt gives a remaining melt to minimum of less than 50,000 km2, resulting in a minimum of around  2.75 million km2  around the 10th February.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1147 on: February 10, 2019, 06:46:24 AM »
JAXA ANTARCTIC Sea Ice Extent : 2,775,911 km2(February 9, 2019)

Extent LOSS of 30k, 0k less than the average LOSS of 30k for this day.

Extent is 7th lowest in the satellite record for this day, behind 2018, 2017, 2011, and 2006, and looking back further, 1997 and 1993. Table Ant3 attached only goes back to 2003. Ho hum

Extent loss from maximum is 416k km2 (2.6%) less than the 10 year average so far, with on average 98.2% of extent loss for the season done and on average 10 days to minimum (19th February).

The Perils of Projections

We have reached the time of year when extent is likely to dither up and down.

The average remaining melt from this day to minimum would produce a minimum of 2.49 million km2, 340k km2 more than the record low in 2017.  Using the average remaining melt from this day to minimum of the 2016 to 2018 years would give a minimum of 2.61 million km2 460k km2 more than the record low in 2017.

Most of the remaining ice is at high concentration. With low concentration ice mostly gone, the remaining ice being solid and close to the coast, melt has been below average every day for approaching two months. Indeed, a simple linear projection of recent 2019 trends in melt gives a remaining melt to minimum of around 50,000 km2, resulting in a minimum of around  2.50 million km2  around the 12th February.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1148 on: February 11, 2019, 05:22:00 AM »
JAXA ANTARCTIC Sea Ice Extent : 2,745,222 km2(February 10, 2019)

Extent LOSS of 31k, 4k less than the average LOSS of 35k for this day.

Extent is 7th lowest in the satellite record for this day, behind 2018, 2017, 2011, and 2006, and looking back further, 1997 and 1993. Table Ant3 attached only goes back to 2003. Ho hum

Extent loss from maximum is 422k km2 (2.7%) less than the 10 year average so far, with on average 98.4% of extent loss for the season done and on average just 9 days to minimum (19th February).

The Perils of Projections

We have reached the time of year when extent is likely to dither up and down.

The average remaining melt from this day to minimum would produce a minimum of 2.50 million km2, 350k km2 more than the record low in 2017.  Using the average remaining melt from this day to minimum of the 2016 to 2018 years would give a minimum of 2.60 million km2 450k km2 more than the record low in 2017.

Most of the remaining ice is at high concentration. With low concentration ice mostly gone, the remaining ice being solid and close to the coast, melt has been below average every day for well over one month.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1149 on: February 12, 2019, 10:56:12 AM »
JAXA ANTARCTIC Sea Ice Extent : 2,696,596 km2(February 11, 2019)

Extent loss of 49k, 12k more than the average loss of 37k for this day.

Extent is 7th lowest in the satellite record for this day, behind 2018, 2017, 2011, and 2006, and looking back further, 1997 and 1993. Table Ant3 attached only goes back to 2003. Ho hum

Extent loss from maximum is 410k km2 (2.6%) less than the 10 year average so far, with on average 98.7% of extent loss for the season done and on average just 8 days to minimum (19th February).

The Perils of Projections

We have reached the time of year when daily extent change is likely to dither above and below zero.

The average remaining melt from this day to minimum would produce a minimum of 2.48 million km2, 330k km2 more than the record low in 2017.  Using the average remaining melt from this day to minimum of the 2016 to 2018 years would give a minimum of 2.57 million km2, 420k km2 more than the record low in 2017.

Most of the remaining ice is at high concentration. With low concentration ice mostly gone, the remaining ice being solid and close to the coast, melt has been below average every day for well over one month - until this day. Late season extra melt? Maybe, maybe not.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)