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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #900 on: August 29, 2018, 09:12:25 AM »
JAXA EXTENT 17,702,916 km2(August 28, 2018)

The Antarctic continues to demonstrate its unpredictability. High extent gains followed by extent losses. Extent is 188 k (1.1%) above 2017 and 703k (4.0%) below the 2010's average.

A maximum of 18.29 million km2 - 230k above a record low, -is the average forecast result with 96 % of the season's average extent gain done, i.e. a second year of very low Antarctic Sea Ice Extent is very possible. Range of outcomes over the last 10 years using remaining melt is in the range of 17.74 to 18.76 million km2. On average 19 days to maximum, but a wide range of just 1 (in 2016) to 35 days to the maximum in the last 10 years.

Antarctic Sea Ice is often dismissed of little importance in the grand scheme of things. The following is a quote from the June 2018 sea ice analysis from NSIDC.

Per NSIDC:-
Quote
Antarctica’s sea ice and ice shelf disintegration[/b]
.... sea ice—a component of the cryosphere that is very sensitive to changing climate and ocean—has an important protective effect on the Antarctic ice sheet.
[/quote]
"Para a Causa do Povo a Luta Continua!"
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #901 on: August 30, 2018, 10:02:49 AM »
JAXA EXTENT 17,691,015 km2(August 29, 2018)

You will see from the first table attached that on this date was the maximum extent for 2016. It was from then that sea ice extent in Antarctica essentially flipped from a gradual increase year by year towards record lows from then on. This is the third year of that downward trend.
 
The Antarctic continues to demonstrate its unpredictability. High extent gains followed by extent losses. Extent is 183 k (1.0%) above 2017 and 758k (4.3%) below the 2010's average.

A maximum of 18.24 million km2 - 180k above a record low, -is the average forecast result with 96.6 % of the season's average extent gain done, i.e. a second year of very low Antarctic Sea Ice Extent is very likely. Range of outcomes over the last 10 years using remaining melt is in the range of 17.69 to 18.72 million km2. On average 18 days to maximum, but a wide range of just zero days (in 2016) to 34 days (2015) to the maximum in the last 10 years.

Antarctic Sea Ice is often dismissed of little importance in the grand scheme of things. The following is a quote from the June 2018 sea ice analysis from NSIDC.

Per NSIDC:-
Quote
Antarctica’s sea ice and ice shelf disintegration[/b]
.... sea ice—a component of the cryosphere that is very sensitive to changing climate and ocean—has an important protective effect on the Antarctic ice sheet.
[/quote]
« Last Edit: August 30, 2018, 10:49:22 AM by gerontocrat »
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #902 on: September 01, 2018, 10:59:56 AM »
JAXA EXTENT 17,729,021 km2(August 31, 2018)

The Antarctic continues to demonstrate its unpredictability - end of season wobbles. High extent gains followed by extent losses. Extent is 167 k (0.9%) above 2017 and 743k (4.3%) below the 2010's average.

A maximum of 18.22 million km2 - 160k above a record low, is the result from average extent gain with 96.9 % of the season's average extent gain done, i.e. a second year of very low Antarctic sea ice extent is very likely. Range of outcomes over the last 10 years using remaining melt is in the range of 17.73 to 18.67 million km2. On average 16 days to maximum, but a wide range of just zero days to 32 days (2015) to the maximum in the last 10 years.

Antarctic Sea Ice is often dismissed of little importance in the grand scheme of things. The following is a quote from the June 2018 sea ice analysis from NSIDC.

Per NSIDC:-
Quote
Antarctica’s sea ice and ice shelf disintegration[/b]
.... sea ice—a component of the cryosphere that is very sensitive to changing climate and ocean—has an important protective effect on the Antarctic ice sheet.
"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)

gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #903 on: September 05, 2018, 10:32:58 AM »
JAXA EXTENT 17,725,523 km2(September 4, 2018)

The Antarctic continues to demonstrate its unpredictability - end of season wobbles. Extent is 196k (1.1%) above 2017 and 823k (4.6%) below the 2010's average.

A maximum of 18.09 million km2 - 30k above a record low, is the result from average extent gain with 97.7 % of the season's average extent gain done and just 12 days on average to the maximum, i.e. a second year of very low Antarctic sea ice extent is very likely. Range of outcomes over the last 10 years using remaining melt is in the range of 17.78 to 18.68 million km2.

On 26 August ice extent was 17.78 million, and has not risen above that in the 9 days following. It is possible that a new record low maximum at a new record early data has happened.

Antarctic Sea Ice is often dismissed of little importance in the grand scheme of things. The following is a quote from the June 2018 sea ice analysis from NSIDC.

Per NSIDC:-
Quote
Antarctica’s sea ice and ice shelf disintegration[/b]
.... sea ice—a component of the cryosphere that is very sensitive to changing climate and ocean—has an important protective effect on the Antarctic ice sheet.
[/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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Ktb

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Re: Sea Ice Extent around Antarctica
« Reply #904 on: September 06, 2018, 02:08:46 AM »
Another drop tomorrow of ~0 to -25k km^2 will result in 2018 being lowest on record for the day. Thanks in part of course to the whopper of a day 2017 had with a gain of ~190k. (eyeball estimated figures)

gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #905 on: September 06, 2018, 10:13:14 AM »
Another drop tomorrow of ~0 to -25k km^2 will result in 2018 being lowest on record for the day. Thanks in part of course to the whopper of a day 2017 had with a gain of ~190k. (eyeball estimated figures)
Almost but not quite - tomorrow?
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #906 on: September 06, 2018, 10:24:53 AM »
JAXA EXTENT 17,727,541 km2(September 5, 2018)

The Antarctic continues to demonstrate its unpredictability - end of season wobbles. Extent is now just 9 k (0 %) above 2017 and 864 k (4.9%) below the 2010's average.

A maximum of 18.06 million km2 - equal record low, is the result from average extent gain with 97.9 % of the season's average extent gain done and just 11 days on average to the maximum, i.e. a second year of very low Antarctic sea ice extent is very likely. Range of outcomes over the last 10 years using remaining melt is in the range of 17.78 to 18.57 million km2.

On 26 August ice extent was 17.78 million, and has not risen above that in the 10 days following. As each day passes it is more possible that that is a new record low maximum at a new record early date.
______________________________________________________________
Antarctic Sea Ice is often dismissed of little importance in the grand scheme of things. The following is a quote from the June 2018 sea ice analysis from NSIDC.

Per NSIDC:-
Quote
Antarctica’s sea ice and ice shelf disintegration[/b]
.... sea ice—a component of the cryosphere that is very sensitive to changing climate and ocean—has an important protective effect on the Antarctic ice sheet.
"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)

gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #907 on: September 06, 2018, 10:44:53 AM »
So perhaps Antarctic Sea Ice Extent is about to trace a line on the unused part of the graph starting tomorrow.
"Para a Causa do Povo a Luta Continua!"
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steve s

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Re: Sea Ice Extent around Antarctica
« Reply #908 on: September 06, 2018, 06:25:06 PM »
Is volume at an all-time low?

gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #909 on: September 06, 2018, 10:58:26 PM »
Is volume at an all-time low?
I don't think anyone knows. Some of the reasons are given below. The other main reason is that less resources have gone into the measurement of sea ice down south.

https://cpom.org.uk/brief-introduction-antarctic-sea-ice/

The Arctic is an ocean surrounded by continent, whilst the Antarctic is a continent surrounded by ocean. This means that Antarctic sea ice is free to move more equator-ward, into warmer waters and melt. The Antarctic therefore has very little multiyear ice, meaning that average ice thickness is around 1-2m, which is lower than the average 2-3m in the Arctic.

Snowfall is much greater in the Southern Ocean than in the Arctic. The combination of higher snowfall rates and thinner sea ice means that snow ice formation is more common in the Antarctic. Snow ice forms when the snow is heavy enough to push the top of the sea ice below the water surface, flooding some of the snow with sea water which then freezes.
The thick snow covering makes it difficult to get reliable Antarctic sea ice thickness measurements.

This means we are unsure as to how Antarctic sea ice volume, as opposed to extent, has been changing.

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

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Re: Sea Ice Extent around Antarctica
« Reply #910 on: September 07, 2018, 10:13:34 AM »
JAXA EXTENT 17,698,924 km2(September 6, 2018)

The Antarctic continues to demonstrate its unpredictability - end of season wobbles, but extent tending down instead of up. Extent is now 97 k (0.5 %) below 2017, 927 k (5.2%) below the 2010's average, and a record low extent for the day.

A maximum of 18.01 million km2 - a record low, is the result from average extent gain with 98.1% of the season's average extent gain done and just 10 days on average to the maximum, i.e. a second year of very low (and perhaps record low) Antarctic sea ice extent is very likely. Range of outcomes over the last 10 years using remaining melt is in the range of 17.78 to 18.45 million km2.

On 26 August ice extent was 17.78 million, and has not risen above that in the 11 days following. As each day passes it is more possible that that is the new record low maximum at a new record early date.
______________________________________________________________
Antarctic Sea Ice is often dismissed of little importance in the grand scheme of things. The following is a quote from the June 2018 sea ice analysis from NSIDC.

Per NSIDC:-
Quote
Antarctica’s sea ice and ice shelf disintegration[/b]
.... sea ice—a component of the cryosphere that is very sensitive to changing climate and ocean—has an important protective effect on the Antarctic ice sheet.
[/quote]
"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)

gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #911 on: September 07, 2018, 10:29:15 AM »
So perhaps Antarctic Sea Ice Extent is about to trace a line on the unused part of the graph starting tomorrow.

And it did - the pen has boldly marked the graph paper where no line has gone before. Will it continue or will (as is possible) sea ice extent resume its end of season increases?
"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)

Aluminium

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Re: Sea Ice Extent around Antarctica
« Reply #912 on: September 07, 2018, 05:07:31 PM »
September 2-6.

FredBear

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Re: Sea Ice Extent around Antarctica
« Reply #913 on: September 07, 2018, 07:23:48 PM »
September 2-6.
Interesting that the apparent drift is clockwise (southern ocean winds are predominately westerly), but icebergs tend to drift anti-clockwise (mostly closer to the continent).

Tor Bejnar

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Re: Sea Ice Extent around Antarctica
« Reply #914 on: September 07, 2018, 08:39:22 PM »
It is good for me to see the A68-A ice island put into some perspective.  I've been posting, and watching others post, in the Larsen C thread, where it looms large.  Here it occupies approximately 35 pixels.
Arctic ice is healthy for children and other living things.

Stephan

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Re: Sea Ice Extent around Antarctica
« Reply #915 on: September 07, 2018, 09:35:25 PM »
So perhaps Antarctic Sea Ice Extent is about to trace a line on the unused part of the graph starting tomorrow.

And it did - the pen has boldly marked the graph paper where no line has gone before. Will it continue or will (as is possible) sea ice extent resume its end of season increases?
It may well be that we continue on this yet unused part of the graph.
But, look at 1986, 1987, or 2015, a later increase back into already used parts of this graph paper (and thus a higher and later maximum than it seems to be now) is not too unlikely. In my opinion, the unpredictability in the Antarctic is much bigger than in the Arctic.

Grygory

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Re: Sea Ice Extent around Antarctica
« Reply #916 on: September 07, 2018, 10:27:36 PM »
It may well be that we continue on this yet unused part of the graph.
But, look at 1986, 1987, or 2015, a later increase back into already used parts of this graph paper (and thus a higher and later maximum than it seems to be now) is not too unlikely. In my opinion, the unpredictability in the Antarctic is much bigger than in the Arctic.
[/quote]

It seems to me that after seeing the Aluminium's gif, this concentration drops. I think that the summit has already been or will be similar

gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #917 on: September 07, 2018, 10:55:04 PM »
September 2-6.
Interesting that the apparent drift is clockwise (southern ocean winds are predominately westerly), but icebergs tend to drift anti-clockwise (mostly closer to the continent).

I am used to images of a very circular strong antarctic clockwise polar vortex,
underneath at sea level (10m) strong westerlies at a distance from the shore,
and between those strong off-shore westerlies and the Antarctic shore oftimes up to half a dozen lows that cause anticlockwise winds along the coast from time to time.

After 2016, things seemed to change somewhat (based purely on my subjective ad-hoc observations). The polar vortex often messy and irregular, the same with the off-shore westerlies and formation of lows. The attached image of the polar vortex for the 12th Sept seems more typical, as does the surface wind map for that date.

Of course, if the Antarctic polar vortex is starting to do what the Arctic Polar Vortex seems to be doing, then one would eventually see both the westerlies and the circumpolar current start to falter. I think that would qualify as a whoops. I wonder if there are some current  and/or research studies on this.

But this is off-topic - or is it. Maybe not if the sea-ice extent continues to go down instead of up.
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #918 on: September 08, 2018, 08:33:29 AM »
JAXA EXTENT 17,645,848 km2(September 7, 2018)

The Antarctic continues to demonstrate its unpredictability - end of season wobbles, but extent tending down instead of up. Extent is now 130 k (0.7 %) below 2017, and 979 k (5.5%) below the 2010's average, and a record low extent for the day.

A maximum of 17.95 million km2 - a record low, is the result from average extent gain with 98.1% of the season's average extent gain done and just 9 days on average to the maximum, i.e. a second year of very low (and perhaps record low) Antarctic sea ice extent is very likely. Range of outcomes over the last 10 years using remaining melt is in the range of 17.78 to 18.41 million km2.

On 26 August ice extent was 17.78 million, and has not risen above that in the 12 days following. As each day passes it is more possible that that is the new record low maximum at a new record early date.
______________________________________________________________
Antarctic Sea Ice is often dismissed of little importance in the grand scheme of things. The following is a quote from the June 2018 sea ice analysis from NSIDC.

Per NSIDC:-
Quote
Antarctica’s sea ice and ice shelf disintegration[/b]
.... sea ice—a component of the cryosphere that is very sensitive to changing climate and ocean—has an important protective effect on the Antarctic ice sheet.
"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)

gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #919 on: September 08, 2018, 08:38:47 AM »
So perhaps Antarctic Sea Ice Extent is about to trace a line on the unused part of the graph starting tomorrow.

And it did - the pen has boldly marked the graph paper where no line has gone before. Will it continue or will (as is possible) sea ice extent resume its end of season increases?

The bold pen, having writ, went on to write another bit.
"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)

Aluminium

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Re: Sea Ice Extent around Antarctica
« Reply #920 on: September 09, 2018, 08:02:51 AM »
September 4-8.

gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #921 on: September 09, 2018, 08:03:39 AM »
JAXA EXTENT 17,631,546 km2(September 8, 2018)

The Antarctic continues to demonstrate its unpredictability - end of season wobbles, but extent tending down instead of up. Extent is now 219 k (1.2 %) below 2017, and 1,007 k (5.7%) below the 2010's average, and another record low extent for the day.

A maximum of 17.93 million km2 - a record low, is the result from average extent gain with  just 8 days on average to the maximum, i.e. a second year of very low (and perhaps record low) Antarctic sea ice extent is very likely. Range of outcomes over the last 10 years using remaining melt is in the range of 17.78 to 18.44 million km2.

On 26 August ice extent was 17.78 million, and has not risen above that in the 13 days following. As each day passes it is more possible that that is the new record low maximum at a new record early date.
______________________________________________________________
Antarctic Sea Ice is often dismissed of little importance in the grand scheme of things. The following is a quote from the June 2018 sea ice analysis from NSIDC.

Per NSIDC:-
Quote
Antarctica’s sea ice and ice shelf disintegration[/b]
.... sea ice—a component of the cryosphere that is very sensitive to changing climate and ocean—has an important protective effect on the Antarctic ice sheet.
[/quote]
"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)

gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #922 on: September 09, 2018, 08:16:48 AM »
So perhaps Antarctic Sea Ice Extent is about to trace a line on the unused part of the graph starting tomorrow.
And it did - the pen has boldly marked the graph paper where no line has gone before. Will it continue or will (as is possible) sea ice extent resume its end of season increases?
The bold pen, having writ, went on to write another bit.
...and another bit
"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)

gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #923 on: September 10, 2018, 09:53:12 AM »
JAXA EXTENT 17,623,489 km2(September 9, 2018)

The Antarctic continues to demonstrate its unpredictability - end of season wobbles, but extent continues the trend down instead of up. Extent is now 291 k (1.7 %) below 2017, and 1,049 k (6.0%) below the 2010's average, and another record low extent for the day.

A maximum of 17.89 million km2 - a record low, is the result from average extent gain with  just 7 days on average to the maximum, i.e. a second year of very low (and perhaps record low) Antarctic sea ice extent is very likely. Range of outcomes over the last 10 years using remaining melt is in the range of 17.78 to 18.34 million km2.

On 26 August ice extent was 17.78 million, and has not risen above that in the 14 days following. This is unusual (unique?) for this time of year. As each day passes it is more possible that that is the new record low maximum at a new record early date.
______________________________________________________________
Antarctic Sea Ice is often dismissed of little importance in the grand scheme of things. The following is a quote from the June 2018 sea ice analysis from NSIDC.

Per NSIDC:-
Quote
Antarctica’s sea ice and ice shelf disintegration[/b]
.... sea ice—a component of the cryosphere that is very sensitive to changing climate and ocean—has an important protective effect on the Antarctic ice sheet.
"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)

gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #924 on: September 10, 2018, 09:55:34 AM »
So perhaps Antarctic Sea Ice Extent is about to trace a line on the unused part of the graph starting tomorrow.
And it did - the pen has boldly marked the graph paper where no line has gone before. Will it continue or will (as is possible) sea ice extent resume its end of season increases?
The bold pen, having writ, went on to write another bit.
...and another bit
... and yet another bit.
"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)

Aluminium

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Re: Sea Ice Extent around Antarctica
« Reply #925 on: September 11, 2018, 08:24:11 AM »
September 6-10.

gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #926 on: September 11, 2018, 01:37:22 PM »
JAXA EXTENT 17,555,452 km2(September 10, 2018)

I think we are looking at an event out of the ordinary

The Antarctic continues to demonstrate its unpredictability - not so much end of season wobbles, more a continuing trend down instead of end of season up. Extent is now 405 k (2.3 %) below 2017, and 1,149 k (6.5%) below the 2010's average, and another record low extent for the day (5th day in a row).

A maximum of 17.78 million km2 - a record low by 281k km2, is the result from average extent gain with just 6 days on average to the maximum. Range of outcomes over the last 10 years using remaining melt is in the range of 17.78 to 18.17 million km2. This maximum result would be 2nd lowest.  i.e. a second year of very low (and perhaps record low) Antarctic sea ice extent is very likely.

On 26 August ice extent was 17.78 million, and has not risen above that in the 15 days following. This is unusual (unique?) for this time of year. As each day passes it is more possible that that is the new record low maximum at a new record early date.
______________________________________________________________
Antarctic Sea Ice is often dismissed of little importance in the grand scheme of things. The following is a quote from the June 2018 sea ice analysis from NSIDC.

Per NSIDC:-
Quote
Antarctica’s sea ice and ice shelf disintegration[/b]
.... sea ice—a component of the cryosphere that is very sensitive to changing climate and ocean—has an important protective effect on the Antarctic ice sheet.
"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)

gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #927 on: September 11, 2018, 01:46:17 PM »
.. and another big bit

The graph shows that extent at September 10th - is lowest than any other year until melting season is strongly under way in mid-October.

Qu:- Does one declare that the ridiculously low extent of 17.78 million on the ridiculously early date of August 26th date was the 2018 maximum ?
"Para a Causa do Povo a Luta Continua!"
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Viggy

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Re: Sea Ice Extent around Antarctica
« Reply #928 on: September 11, 2018, 06:05:15 PM »
Qu:- Does one declare that the ridiculously low extent of 17.78 million on the ridiculously early date of August 26th date was the 2018 maximum ?

The low pressure systems that caused most of the sea ice reduction in the Bellingshausen and Weddell seas seem to be weakening in general, with significantly less low pressure (less turbulent air near the sea ice boundaries) and colder air temp anomalies over the next 5-10 days ... BUT ...
prelim data on Earthdata shows that sea ice will likely decrease again today.

Also, in 2017, we dipped to a very similar low to today's number, 2 weeks later (17.58M on Sept 25). However, it recovered almost 500,000 sq km in the 2 weeks after.

My guess - we will definitely have a new record low max this year but the 17.78 is not set in stone.

oren

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Re: Sea Ice Extent around Antarctica
« Reply #929 on: September 11, 2018, 07:22:13 PM »
I think it can only be declared with confidence after the beginning of October.

johnm33

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Re: Sea Ice Extent around Antarctica
« Reply #930 on: September 12, 2018, 01:11:06 AM »
There' are big tides from the new moon and serious storms, they're probably responsible for the downturn, I expect a rebound in 3-4 days but not much if the storms continue. We'll see.

Klondike Kat

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Re: Sea Ice Extent around Antarctica
« Reply #931 on: September 12, 2018, 09:47:30 PM »
There' are big tides from the new moon and serious storms, they're probably responsible for the downturn, I expect a rebound in 3-4 days but not much if the storms continue. We'll see.

I agree.  It is much too early to declare a maximum yet. 

Aluminium

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Re: Sea Ice Extent around Antarctica
« Reply #932 on: September 13, 2018, 06:57:33 AM »
September 8-12.

gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #933 on: September 13, 2018, 11:13:32 AM »
JAXA EXTENT 17,548,783 km2(September 12, 2018)

I really do think we are looking at an event out of the ordinary

The Antarctic continues to demonstrate its unpredictability - not so much end of season wobbles, more a continuing trend down instead of end of season up. Extent is now 514 k (2.9 %) below 2017, and 1.191 k (6.8%) below the 2010's average, and another record low extent for the day (7 days in a row).

A maximum of 17.72 million km2 - a record low by 340 k km2, is the result from average extent gain with just 4 days on average to the maximum. Range of outcomes over the last 10 years using remaining melt is in the range of 17.78 to 17.95 million km2. This maximum result would be lowest.  i.e. a second year of record low Antarctic sea ice extent is very likely.

On 26 August ice extent was 17.78 million, and has not risen above that in the 17 days following. This is unusual (unique?) for this time of year. As each day passes it is more possible that this is the new record low maximum at a new record early date.
______________________________________________________________
Antarctic Sea Ice is often dismissed of little importance in the grand scheme of things. The following is a quote from the June 2018 sea ice analysis from NSIDC.

Per NSIDC:-
Quote
Antarctica’s sea ice and ice shelf disintegration[/b]
.... sea ice—a component of the cryosphere that is very sensitive to changing climate and ocean—has an important protective effect on the Antarctic ice sheet.
"Para a Causa do Povo a Luta Continua!"
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #934 on: September 13, 2018, 11:15:31 AM »
And the Jaxa graph to complete the picture....
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #935 on: September 14, 2018, 10:00:15 AM »
JAXA EXTENT 17,523,844 km2(September 13, 2018)

I really do think we are looking at an event out of the ordinary

The Antarctic continues to demonstrate its unpredictability - not so much end of season wobbles, more a continuing trend down instead of end of season up.  Extent is 504 k (2.9 %) below 2017, and 1.224 k (7.0%) below the 2010's average, and another record low extent for the day (8 days in a row).

A maximum of 17.67 million km2 - a record low by 390 k km2, is the result from average extent gain with just 3 days on average to the maximum. Range of outcomes over the last 10 years from remaining melt is in the range of 17.78 to 17.98 million km2. This maximum result would be lowest.  i.e. a second year of record low Antarctic sea ice extent is very likely.

On 26 August ice extent was 17.78 million, and has not risen above that in the 17 days following. This is unusual (unique?) for this time of year. As each day passes it is more possible that this is the new record low maximum at a new record early date.
______________________________________________________________
Antarctic Sea Ice is often dismissed of little importance in the grand scheme of things. The following is a quote from the June 2018 sea ice analysis from NSIDC.

Per NSIDC:-
Quote
Antarctica’s sea ice and ice shelf disintegration[/b]
.... sea ice—a component of the cryosphere that is very sensitive to changing climate and ocean—has an important protective effect on the Antarctic ice sheet.
"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)

gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #936 on: September 14, 2018, 10:06:46 AM »
And the Jaxa graph to complete the picture....
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Tony Mcleod

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Re: Sea Ice Extent around Antarctica
« Reply #937 on: September 15, 2018, 06:05:40 AM »
Do you a link to those graphs gerontocrat?

Aluminium

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Re: Sea Ice Extent around Antarctica
« Reply #938 on: September 15, 2018, 10:51:21 AM »
September 10-14.

gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #939 on: September 15, 2018, 11:00:49 AM »
Do you a link to those graphs gerontocrat?

Sorry, no link.

I constructed them in my laptop from JAXA and NSIDC data so they are buried in my spreadsheets, and I update them daily and copy them into PAINT to create the png copies.  I do not have my own website, so have no way of making a link. I am not sure if I did have a website, I would have the time to maintain it.
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #940 on: September 15, 2018, 11:02:56 AM »
Only have time to post the JAXA graph to show the extent pen is still writing on the blank part of the graph paper.
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Lurk

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Re: Sea Ice Extent around Antarctica
« Reply #941 on: September 16, 2018, 05:29:12 AM »
JAXA EXTENT 17,523,844 km2(September 13, 2018)

I really do think we are looking at an event out of the ordinary

Hello G., I just noticed recently the global sie which brought me to have look in here. Your comments caught my attention. Before I did I roughly calc that the current antarctic sie/area is ~2.4% below other lowest records at this time, and about 5% below the 2000-2010 avg. Looking at the large variations lowest to highest for maximums in the recent records those numbers aren't that big a variation (and would usually suggest some natural variations happening), except today being a new record low maximum. 

It reminded me of the last decades pattern in the arctic of how it was the maximums that decreased little by little to new record lows and then a few times the minimums subsequently went off the charts, not only sei but thickness/piomass especially over the years. I'm no 'experienced' observer of the antarctic ice details but this situation especially your comments has pricked my ears up.

I' not sure if this observation is of note, but the 2000 & 2001 maximums also hit a major record fall in sie/area for that period. This coming on the back of the 98 el nino and record global temps back then.  The others years that had significant dips seem to be (via nsdic) 2006, 2008, and 2011. I;m only thinking out loud and wondering maybe there is something to be seen from those years that could 'hint' at what is behind the current "sudden" drop? eg the 2015/2016 el nino and 2 years later today?

Like I said I don;t follow this closely so have no idea of recent shifts in ocean or air temps around the antarctic, so only running what I have noticed up the flag pole for those more experienced and knowledgeable of the history. I'm certainly curious about the current compaction of the sea ice and the overall piomass down there at this maximum period. Has that fallen away at all, because iirc isn't that what happened in the arctic max when the max sei was falling to new record lows?

I have no answers only open ended questions, and will have to pay more attention for a while as new data comes out from various sources. I hope the new Cryosat 2 can add some good quality new data in the next year ongoing.
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #942 on: September 16, 2018, 11:54:30 AM »
JAXA EXTENT 17,624,124 km2(September 15, 2018)

I really do think we are looking at an event out of the ordinary, but is it merely a temporary blip

The Antarctic continues to demonstrate its unpredictability - not so much end of season wobbles, more a continuing trend down instead of end of season up.  But then a 100k increase over 2 days.

Extent is 304 k (1.7 %) below 2017, and 1.117 k (6.3%) below the 2010's average, and another record low extent for the day (10 days in a row).

A maximum of 17.76 million km2 - a record low by 300 k km2, is the result from average extent gain with just 1 day on average to the maximum. Range of outcomes over the last 10 years from remaining melt is in the range of 17.78 to 18.17 million km2. This maximum result would be 4th lowest.  i.e. a second year of record low Antarctic sea ice extent is still likely.

On 26 August ice extent was 17.78 million, and has not risen above that in the 20 days following. This is unusual (unique?) for this time of year. As each day passes it is more possible that this is the new record low maximum at a new record early date.
______________________________________________________________
Antarctic Sea Ice is often dismissed of little importance in the grand scheme of things. The following is a quote from the June 2018 sea ice analysis from NSIDC.

Per NSIDC:-
Quote
Antarctica’s sea ice and ice shelf disintegration[/b]
.... sea ice—a component of the cryosphere that is very sensitive to changing climate and ocean—has an important protective effect on the Antarctic ice sheet.
[/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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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #943 on: September 16, 2018, 12:13:20 PM »
The JAXA graph shows the extent pen is still writing on the blank part of the graph paper. (10 days so far). But extent is going up again.

https://ads.nipr.ac.jp/vishop.ver1/vishop-extent.html?S
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #944 on: September 16, 2018, 12:39:25 PM »
I have no answers only open ended questions, and will have to pay more attention for a while as new data comes out from various sources. I hope the new Cryosat 2 can add some good quality new data in the next year ongoing.

"I have no answers only open ended questions". Join the crowd.

This is my take on it.

Antarctic Sea ice extent gradually increased in the decades to around 2012.
Then in 2013 and 2014 increased by leaps and bound to record highs.
In 2015 and 2016 down again to record lows. In 2016 / 17 the drop in extent was spectacular.
Meanwhile, the GRACE project showed that Antarctic Ice sheet loss had greatly increased from 2002 to 2016.

So - has AGW really broken through the protecting circumpolar vortex and circumpolar ocean current?  How much is the ozone hole still muddying the waters?

Only more years of data will really tell us, ice-sat2 and the GRACE Follow-on project will no doubt help. So I keep watching - a record low extent (if it happens) in 2018 would be another bit of data suggesting a trend down.
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iceman

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Re: Sea Ice Extent around Antarctica
« Reply #945 on: September 16, 2018, 03:50:48 PM »
... a later increase back into already used parts of this graph paper (and thus a higher and later maximum than it seems to be now) is not too unlikely.
   ....

I thought so too. Though the decline (before the recent blip up) is more moderate than from some previous years during the same part of the cycle, it's still remarkable from such a low starting point in August.

Stephan

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Re: Sea Ice Extent around Antarctica
« Reply #946 on: September 16, 2018, 10:07:13 PM »
I have just compared the decadal averages maxima with the decadal averages for Sept. 15:
80s: on 15.9. SIE was 18.57, the max (on 19.9.) SIE was 18.61 (an increase of 0.04 mio km²)
90s: on 15.9. SIE was 18.48, the max (on 21.9.) SIE was 18.54 (an increase of 0.06 mio km²)
00s: on 15.9. SIE was 18.58*, the max (on 22.9.) SIE was 18.72 (an increase of 0.14 mio km²)
* I have subtracted 0.10 mio. km² from the line, because there was a kind of "step" in that week.
10s: on 15.9. SIE was 18.62, the max (on 29.9.) SIE was 18.76 (an increase of 0.16 mio km²)

The SIE on 15.9.2018 was 17.62 mio. km²; the maximum so far this season on 26.8. was 17.76 mio km²
With that given, the actual extent plus the increases of the decadal averages deliver 17.66 to 17.78 mio. km² for the annual maximum in September, and only the increase derived from the 10s average gives us a new maximum, higher than the value from 26.8.2018.

I know that this is speculative. The annual variability is high - and daily changes can be higher than the calculated increases above. But it can well be that we already saw the annual maximum in August. On the other hand, we should wait at least another two weeks to be really sure.

Aluminium

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Re: Sea Ice Extent around Antarctica
« Reply #947 on: September 17, 2018, 07:39:21 AM »
September 12-16.

gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #948 on: September 17, 2018, 10:56:09 AM »
JAXA EXTENT 17,751,576 km2(September 16, 2018)

I really do think we are looking at an event out of the ordinary, but is it merely a temporary blip ?

The Antarctic continues to demonstrate its unpredictability - not so much end of season wobbles, more a continuing trend down instead of end of season up.  But then a 228k increase over 3 days.

Extent is 162 k 01.9 %) below 2017, 24 k (0.1 %) below 2016, and 988 k (5.6%) below the 2010's average, and another record low extent for the day - just - (11 days in a row).

A maximum of 17.88  million km2 - a record low by just 30 k km2, is the result from average extent gain with just 1 day on average to the maximum. Range of outcomes over the last 10 years from remaining melt is in the range of 17.78 to 18.31 million km2. This maximum result would be 4th lowest.  i.e. a second year of record low Antarctic sea ice extent is still likely.

On 26 August ice extent was 17.78 million, and has not risen above that in the 21 days following. This is unusual (unique?) for this time of year. As each day passes it is more possible that this is the new record low maximum at a new record early date. However once more small increase will change that.
______________________________________________________________
Antarctic Sea Ice is often dismissed of little importance in the grand scheme of things. The following is a quote from the June 2018 sea ice analysis from NSIDC.

Per NSIDC:-
Quote
Antarctica’s sea ice and ice shelf disintegration[/b]
.... sea ice—a component of the cryosphere that is very sensitive to changing climate and ocean—has an important protective effect on the Antarctic ice sheet.
"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)

gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #949 on: September 17, 2018, 10:57:45 AM »
JAXA Graph - still a record low, but maybe the last day.
"Para a Causa do Povo a Luta Continua!"
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