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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1550 on: November 13, 2020, 12:52:33 PM »
JAXA ANTARCTIC SEA ICE EXTENT:  16,593,885 KM2 as at 12-Nov-2020

- Extent loss on this day 91k, 40 k less than the average loss on this day (of the last 10 years) of 131k,
- Extent loss from maximum on this date is 2.27 million km2, 0.27 million km2, (11%) less than the 10 year average of 2.54 million km2.
- Extent is at position #27 in the satellite record of which 15 lower values are in the years before 2000

- Extent is  1,839 k MORE than 2016
- Extent is  906 k MORE than 2017
- Extent is  1,065 k MORE than 2018
- Extent is  1,281 k MORE than 2019
- Extent is  162 k MORE than the 1980's Average

- On average 16.0% of ice loss  from maximum to minimum done, and 101 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 3.26 million km2, 1.11 million km2 above the 2017 record low minimum of 2.15 million km2.
_____________________________________________
Despite yet another lower than average extent loss, total extent went up another two places to 27th lowest from 29th lowest for the day.
___________________________________________________________
N.B. Click on image  for full-size
"Para a Causa do Povo a Luta Continua!"
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1551 on: November 14, 2020, 11:42:04 AM »
JAXA ANTARCTIC SEA ICE EXTENT:  16,522,547 KM2 as at 13-Nov-2020

- Extent loss on this day 71k, 59 k less than the average loss on this day (of the last 10 years) of 130k,
- Extent loss from maximum on this date is 2.34 million km2, 0.33 million km2, (12%) less than the 10 year average of 2.67 million km2.
- Extent is at position #28 in the satellite record of which 16 lower values are in the years before 2000

- Extent is  2,053 k MORE than 2016
- Extent is  1,012 k MORE than 2017
- Extent is  1,089 k MORE than 2018
- Extent is  1,346 k MORE than 2019
- Extent is  182 k MORE than the 1980's Average

- On average 16.8% of ice loss  from maximum to minimum done, and 100 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 3.31 million km2, 1.17 million km2 above the 2017 record low minimum of 2.15 million km2.
_____________________________________________
And yet another lower than average extent loss, total extent went down another one place to 28th lowest from 27th lowest for the day.
___________________________________________________________
N.B. Click on image  for full-size
"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 #1552 on: November 15, 2020, 12:14:04 PM »
JAXA ANTARCTIC SEA ICE EXTENT:  16,456,263 KM2 as at 14-Nov-2020

- Extent loss on this day 66k, 67 k less than the average loss on this day (of the last 10 years) of 133k,
- Extent loss from maximum on this date is 2.40 million km2, 0.39 million km2, (14%) less than the 10 year average of 2.80 million km2.
- Extent is at position #32 in the satellite record of which 18 lower values are in the years before 2000

- Extent is  2,202 k MORE than 2016
- Extent is  1,111 k MORE than 2017
- Extent is  1,164 k MORE than 2018
- Extent is  1,405 k MORE than 2019
- Extent is  227 k MORE than the 1980's Average

- On average 17.6% of ice loss  from maximum to minimum done, and 99 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 3.38 million km2, 1.23 million km2 above the 2017 record low minimum of 2.15 million km2.
_____________________________________________
Lower than average extent loss continues , total extent goes down four places to 32nd lowest from 28th lowest for the day.
___________________________________________________________
N.B. Click on image  for full-size
"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 #1553 on: November 16, 2020, 10:26:15 AM »
JAXA ANTARCTIC SEA ICE EXTENT:  16,350,115 KM2 as at 15-Nov-2020

- Extent loss on this day 106k, 21 k less than the average loss on this day (of the last 10 years) of 127k,
- Extent loss from maximum on this date is 2.51 million km2, 0.42 million km2, (14%) less than the 10 year average of 2.93 million km2.
- Extent is at position #34 in the satellite record of which 19 lower values are in the years before 2000

- Extent is  2,253 k MORE than 2016
- Extent is  1,174 k MORE than 2017
- Extent is  1,215 k MORE than 2018
- Extent is  1,369 k MORE than 2019
- Extent is  236 k MORE than the 1980's Average

- On average 18.5% of ice loss  from maximum to minimum done, and 98 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 3.40 million km2, 1.26 million km2 above the 2017 record low minimum of 2.15 million km2.
_____________________________________________
Lower than average extent loss continues for yet another day , total extent goes down two places to 34th lowest from 32nd lowest for the day.
___________________________________________________________
N.B. Click on image  for full-size
"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 #1554 on: November 17, 2020, 11:21:39 AM »
JAXA ANTARCTIC SEA ICE EXTENT:  16,264,166 KM2 as at 16-Nov-2020

- Extent loss on this day 86k, 39 k less than the average loss on this day (of the last 10 years) of 125k,
- Extent loss from maximum on this date is 2.60 million km2, 0.46 million km2, (15%) less than the 10 year average of 3.06 million km2.
- Extent is at position #34 in the satellite record of which 19 lower values are in the years before 2000

- Extent is  2,352 k MORE than 2016
- Extent is  1,242 k MORE than 2017
- Extent is  1,287 k MORE than 2018
- Extent is  1,363 k MORE than 2019
- Extent is  247 k MORE than the 1980's Average

- On average 19.2% of ice loss  from maximum to minimum done, and 97 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 3.44 million km2, 1.29 million km2 above the 2017 record low minimum of 2.15 million km2.
___________________________________________________________
N.B. Click on image  for full-size
"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 #1555 on: November 18, 2020, 10:50:02 AM »
JAXA ANTARCTIC SEA ICE EXTENT:  16,165,938 KM2 as at 17-Nov-2020

- Extent loss on this day 98k, 37 k less than the average loss on this day (of the last 10 years) of 135k,
- Extent loss from maximum on this date is 2.70 million km2, 0.50 million km2, (16%) less than the 10 year average of 3.19 million km2.
- Extent is at position #35 in the satellite record of which 18 lower values are in the years before 2000

- Extent is  2,438 k MORE than 2016
- Extent is  1,318 k MORE than 2017
- Extent is  1,343 k MORE than 2018
- Extent is  1,354 k MORE than 2019
- Extent is  248 k MORE than the 1980's Average

- On average 20.1% of ice loss  from maximum to minimum done, and 96 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 3.48 million km2, 1.33 million km2 above the 2017 record low minimum of 2.15 million km2.
_______________________________________________
And again a lower than average extent loss on this day , total extent goes down one place to 35th lowest (i.e. 8th highest) from 34th lowest for the day.
___________________________________________________________
N.B. Click on image  for full-size
"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 #1556 on: November 19, 2020, 11:07:34 AM »
JAXA ANTARCTIC SEA ICE EXTENT:  16,086,652 KM2 as at 18-Nov-2020

- Extent loss on this day 79k, 38 k less than the average loss on this day (of the last 10 years) of 117k,
- Extent loss from maximum on this date is 2.77 million km2, 0.54 million km2, (16%) less than the 10 year average of 3.32 million km2.
- Extent is at position #36 in the satellite record of which 18 lower values are in the years before 2000

- Extent is  2,468 k MORE than 2016
- Extent is  1,408 k MORE than 2017
- Extent is  1,340 k MORE than 2018
- Extent is  1,402 k MORE than 2019
- Extent is  292 k MORE than the 1980's Average

- On average 20.9% of ice loss  from maximum to minimum done, and 95 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 3.52 million km2, 1.37 million km2 above the 2017 record low minimum of 2.15 million km2.
______________________________________________
A lower than average extent loss on this day for the ninth day in a row:- total extent goes down one place to 36th lowest (i.e. 7th highest) from 35th lowest for the day.
___________________________________________________________
N.B. Click on image  for full-size
"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 #1557 on: November 20, 2020, 11:00:39 AM »
JAXA ANTARCTIC SEA ICE EXTENT:  15,970,537 KM2 as at 19-Nov-2020

- Extent loss on this day 116k, 14 k less than the average loss on this day (of the last 10 years) of 130k,
- Extent loss from maximum on this date is 2.89 million km2, 0.56 million km2, (16%) less than the 10 year average of 3.45 million km2.
- Extent is at position #35 in the satellite record of which 18 lower values are in the years before 2000

- Extent is  2,527 k MORE than 2016
- Extent is  1,469 k MORE than 2017
- Extent is  1,359 k MORE than 2018
- Extent is  1,426 k MORE than 2019
- Extent is  303 k MORE than the 1980's Average

- On average 21.7% of ice loss  from maximum to minimum done, and 94 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 3.53 million km2, 1.38 million km2 above the 2017 record low minimum of 2.15 million km2.
___________________________________________________________
N.B. Click on image  for full-size
"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 #1558 on: November 21, 2020, 10:58:16 AM »
JAXA ANTARCTIC SEA ICE EXTENT:  15,834,068 KM2 as at 20-Nov-2020

- Extent loss on this day 136k, 7 k less than the average loss on this day (of the last 10 years) of 143k,
- Extent loss from maximum on this date is 3.03 million km2, 0.57 million km2, (16%) less than the 10 year average of 3.60 million km2.
- Extent is at position #34 in the satellite record of which 17 lower values are in the years before 2000

- Extent is  2,595 k MORE than 2016
- Extent is  1,523 k MORE than 2017
- Extent is  1,315 k MORE than 2018
- Extent is  1,452 k MORE than 2019
- Extent is  297 k MORE than the 1980's Average

- On average 22.6% of ice loss  from maximum to minimum done, and 93 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 3.54 million km2, 1.39 million km2 above the 2017 record low minimum of 2.15 million km2.
___________________________________________________________
N.B. Click on image  for full-size
"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 #1559 on: November 22, 2020, 12:00:23 PM »
JAXA ANTARCTIC SEA ICE EXTENT:  15,675,481 KM2 as at 21-Nov-2020

- Extent loss on this day 159k, 12 k more than the average loss on this day (of the last 10 years) of 147k,
- Extent loss from maximum on this date is 3.19 million km2, 0.55 million km2, (15%) less than the 10 year average of 3.74 million km2.
- Extent is at position #34 in the satellite record of which 17 lower values are in the years before 2000

- Extent is  2,592 k MORE than 2016
- Extent is  1,532 k MORE than 2017
- Extent is  1,304 k MORE than 2018
- Extent is  1,451 k MORE than 2019
- Extent is  282 k MORE than the 1980's Average

- On average 23.5% of ice loss  from maximum to minimum done, and 92 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 3.52 million km2, 1.38 million km2 above the 2017 record low minimum of 2.15 million km2.
___________________________________________________________
N.B. Click on image  for full-size
"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 #1560 on: November 22, 2020, 12:38:20 PM »
The first day of above average extent loss since around three weeks. A single event or a start into a period of faster than average losses?
It is too late just to be concerned about Climate Change

The Walrus

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Re: Sea Ice Extent around Antarctica
« Reply #1561 on: November 22, 2020, 12:59:12 PM »
The first day of above average extent loss since around three weeks. A single event or a start into a period of faster than average losses?

Typically when the ice has remained high for this long, it is followed by faster losses.  I would guess we should start seeing some above average losses.

steve s

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Re: Sea Ice Extent around Antarctica
« Reply #1562 on: November 22, 2020, 03:53:15 PM »
Extent is measured as area, not volume. Winds can spread the sea ice, but that new ice would be relatively thin and should melt rapidly once holes form and sea water is exposed to sunlight for many hours each day.

gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1563 on: November 23, 2020, 12:33:03 PM »
JAXA ANTARCTIC SEA ICE EXTENT:  15,492,670 KM2 as at 22-Nov-2020

- Extent loss on this day 183k, 57 k more than the average loss on this day (of the last 10 years) of 126k,
- Extent loss from maximum on this date is 3.37 million km2, 0.49 million km2, (13%) less than the 10 year average of 3.86 million km2.
- Extent is at position #33 in the satellite record of which 16 lower values are in the years before 2000

- Extent is  2,494 k MORE than 2016
- Extent is  1,504 k MORE than 2017
- Extent is  1,278 k MORE than 2018
- Extent is  1,428 k MORE than 2019
- Extent is  259 k MORE than the 1980's Average

- On average 24.3% of ice loss  from maximum to minimum done, and 91 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 3.47 million km2, 1.32 million km2 above the 2017 record low minimum of 2.15 million km2.
___________________________________________________________
N.B. Click on image  for full-size
"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 #1564 on: November 24, 2020, 11:39:40 AM »
JAXA ANTARCTIC SEA ICE EXTENT:  15,290,448 KM2 as at 23-Nov-2020

- Extent loss on this day 202k, 66 k more than the average loss on this day (of the last 10 years) of 136k,
- Extent loss from maximum on this date is 3.57 million km2, 0.42 million km2, (10%) less than the 10 year average of 3.99 million km2.
- Extent is at position #33 in the satellite record of which 16 lower values are in the years before 2000

- Extent is  2,394 k MORE than 2016
- Extent is  1,478 k MORE than 2017
- Extent is  1,212 k MORE than 2018
- Extent is  1,379 k MORE than 2019
- Extent is  211 k MORE than the 1980's Average

- On average 25.1% of ice loss  from maximum to minimum done, and 90 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 3.40 million km2, 1.25 million km2 above the 2017 record low minimum of 2.15 million km2.
___________________________________________________________
N.B. Click on image  for full-size
"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 #1565 on: November 25, 2020, 12:45:00 PM »
JAXA ANTARCTIC SEA ICE EXTENT:  15,140,747 KM2 as at 24-Nov-2020

- Extent loss on this day 150k, 3 k less than the average loss on this day (of the last 10 years) of 153k,
- Extent loss from maximum on this date is 3.72 million km2, 0.42 million km2, (10%) less than the 10 year average of 4.14 million km2.
- Extent is at position #33 in the satellite record of which 16 lower values are in the years before 2000

- Extent is  2,404 k MORE than 2016
- Extent is  1,493 k MORE than 2017
- Extent is  1,153 k MORE than 2018
- Extent is  1,370 k MORE than 2019
- Extent is  212 k MORE than the 1980's Average

- On average 26.1% of ice loss  from maximum to minimum done, and 89 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 3.41 million km2, 1.26 million km2 above the 2017 record low minimum of 2.15 million km2.
___________________________________________________________
N.B. Click on image  for full-size
"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 #1566 on: November 26, 2020, 10:47:46 AM »
JAXA ANTARCTIC SEA ICE EXTENT:  14,932,709 KM2 as at 25-Nov-2020

- Extent loss on this day 208k, 61 k more than the average loss on this day (of the last 10 years) of 147k,
- Extent loss from maximum on this date is 3.93 million km2, 0.36 million km2, (8%) less than the 10 year average of 4.29 million km2.
- Extent is at position #31 in the satellite record of which 14 lower values are in the years before 2000

- Extent is  2,317 k MORE than 2016
- Extent is  1,384 k MORE than 2017
- Extent is  1,069 k MORE than 2018
- Extent is  1,332 k MORE than 2019
- Extent is  161 k MORE than the 1980's Average

- On average 27.0% of ice loss  from maximum to minimum done, and 88 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 3.34 million km2, 1.20 million km2 above the 2017 record low minimum of 2.15 million km2.
___________________________________________________________
N.B. Click on image  for full-size
"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 #1567 on: November 27, 2020, 11:22:36 AM »
JAXA ANTARCTIC SEA ICE EXTENT:  14,732,214 KM2 as at 26-Nov-2020

- Extent loss on this day 200k, 48 k more than the average loss on this day (of the last 10 years) of 152k,
- Extent loss from maximum on this date is 4.13 million km2, 0.31 million km2, (7%) less than the 10 year average of 4.43 million km2.
- Extent is at position #30 in the satellite record of which 14 lower values are in the years before 2000

- Extent is  2,271 k MORE than 2016
- Extent is  1,393 k MORE than 2017
- Extent is  1,016 k MORE than 2018
- Extent is  1,318 k MORE than 2019
- Extent is  130 k MORE than the 1980's Average

- On average 27.9% of ice loss  from maximum to minimum done, and 87 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 3.30 million km2, 1.15 million km2 above the 2017 record low minimum of 2.15 million km2.
____________________________________________________________________________
High extent losses drop extent from 33rd to 30th lowest in 2 days

________________________________________
N.B. Click on image  for full-size
"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 #1568 on: November 28, 2020, 12:00:03 PM »
JAXA ANTARCTIC SEA ICE EXTENT:  14,537,072 KM2 as at 27-Nov-2020

- Extent loss on this day 195k, 56 k more than the average loss on this day (of the last 10 years) of 139k,
- Extent loss from maximum on this date is 4.32 million km2, 0.25 million km2, (5%) less than the 10 year average of 4.57 million km2.
- Extent is at position #30 in the satellite record of which 14 lower values are in the years before 2000

- Extent is  2,219 k MORE than 2016
- Extent is  1,285 k MORE than 2017
- Extent is  969 k MORE than 2018
- Extent is  1,263 k MORE than 2019
- Extent is  107 k MORE than the 1980's Average

- On average 28.8% of ice loss  from maximum to minimum done, and 86 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 3.24 million km2, 1.09 million km2 above the 2017 record low minimum of 2.15 million km2.
___________________________________________________________
N.B. Click on image  for full-size
"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 #1569 on: November 29, 2020, 12:01:51 PM »
JAXA ANTARCTIC SEA ICE EXTENT:  14,309,198 KM2 as at 28-Nov-2020

- Extent loss on this day 228k, 66 k more than the average loss on this day (of the last 10 years) of 162k,
- Extent loss from maximum on this date is 4.55 million km2, 0.19 million km2, (4%) less than the 10 year average of 4.74 million km2.
- Extent is at position #28 in the satellite record of which 12 lower values are in the years before 2000

- Extent is  2,192 k MORE than 2016
- Extent is  1,166 k MORE than 2017
- Extent is  876 k MORE than 2018
- Extent is  1,156 k MORE than 2019
- Extent is  60 k MORE than the 1980's Average

- On average 29.9% of ice loss  from maximum to minimum done, and 85 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 3.17 million km2, 1.03 million km2 above the 2017 record low minimum of 2.15 million km2.
____________________________________________________________________________
The extremely high extent loss on this day drops extent from 30th to 28th lowest in the satellite record.
___________________________________________________________
N.B. Click on image  for full-size
"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 #1570 on: November 30, 2020, 11:06:26 AM »
JAXA ANTARCTIC SEA ICE EXTENT:  14,186,477 KM2 as at 29-Nov-2020

- Extent loss on this day 123k, 54 k less than the average loss on this day (of the last 10 years) of 177k,
- Extent loss from maximum on this date is 4.67 million km2, 0.24 million km2, (5%) less than the 10 year average of 4.92 million km2.
- Extent is at position #30 in the satellite record of which 14 lower values are in the years before 2000

- Extent is  2,273 k MORE than 2016
- Extent is  1,228 k MORE than 2017
- Extent is  924 k MORE than 2018
- Extent is  1,178 k MORE than 2019
- Extent is  124 k MORE than the 1980's Average

- On average 31.0% of ice loss  from maximum to minimum done, and 84 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 3.23 million km2, 1.08 million km2 above the 2017 record low minimum of 2.15 million km2.
___________________________________________________________

The low extent loss on this day sends extent back to 30th from 28th lowest in the satellite record
____________________________________________________________________________
N.B. Click on image  for full-size
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1571 on: December 01, 2020, 04:59:08 PM »
JAXA ANTARCTIC SEA ICE EXTENT:  14,068,170 KM2 as at 30-Nov-2020

- Extent loss on this day 118k, 50 k less than the average loss on this day (of the last 10 years) of 168k,
- Extent loss from maximum on this date is 4.79 million km2, 0.30 million km2, (6%) less than the 10 year average of 5.09 million km2.
- Extent is at position #31 in the satellite record of which 15 lower values are in the years before 2000

- Extent is  2,370 k MORE than 2016
- Extent is  1,268 k MORE than 2017
- Extent is  969 k MORE than 2018
- Extent is  1,206 k MORE than 2019
- Extent is  205 k MORE than the 1980's Average

- On average 32.0% of ice loss  from maximum to minimum done, and 83 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 3.28 million km2, 1.13 million km2 above the 2017 record low minimum of 2.15 million km2.
___________________________________________________________

The low extent loss on this day sends extent back to 31st from 30th lowest in the satellite record
___________________________________________________________
N.B. Click on image  for full-size
"Para a Causa do Povo a Luta Continua!"
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1572 on: December 01, 2020, 05:15:38 PM »
JAXA Data - a bit more

I attach the November monthly average graph. At 15.12 million km2, it is 2.5 million km2 above the extraordinary low of 2016, and 11th HIGHEST in the satellite record.

I also attach the 365 day trailing average graph which shows best the extent of sea ice recovery from those extraordinary lows of 2016 (and the scale of the spike from the massive extent increases in 2014-15).

I also attach the plume of projections of the 2021 minimum.
« Last Edit: December 01, 2020, 05:30:41 PM by gerontocrat »
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1573 on: December 02, 2020, 12:40:19 PM »
JAXA ANTARCTIC SEA ICE EXTENT:  13,906,968 KM2 as at 01-Dec-2020

- Extent loss on this day 161k, 12 k less than the average loss on this day (of the last 10 years) of 173k,
- Extent loss from maximum on this date is 4.95 million km2, 0.31 million km2, (6%) less than the 10 year average of 5.27 million km2.
- Extent is at position #32 in the satellite record of which 16 lower values are in the years before 2000

- Extent is  2,398 k MORE than 2016
- Extent is  1,266 k MORE than 2017
- Extent is  942 k MORE than 2018
- Extent is  1,228 k MORE than 2019
- Extent is  234 k MORE than the 1980's Average

- On average 33.2% of ice loss  from maximum to minimum done, and 82 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 3.29 million km2, 1.14 million km2 above the 2017 record low minimum of 2.15 million km2.
_____________________________________
A slightly below average sea ice loss still results in extent down one place to 32nd lowest.
___________________________________________________________
N.B. Click on image  for full-size
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1574 on: December 03, 2020, 10:38:56 AM »
JAXA ANTARCTIC SEA ICE EXTENT:  13,734,595 KM2 as at 02-Dec-2020

- Extent loss on this day 172k, 10 k less than the average loss on this day (of the last 10 years) of 182k,
- Extent loss from maximum on this date is 5.13 million km2, 0.33 million km2, (6%) less than the 10 year average of 5.45 million km2.
- Extent is at position #32 in the satellite record of which 16 lower values are in the years before 2000

- Extent is  2,416 k MORE than 2016
- Extent is  1,298 k MORE than 2017
- Extent is  952 k MORE than 2018
- Extent is  1,226 k MORE than 2019
- Extent is  239 k MORE than the 1980's Average

- On average 34.3% of ice loss  from maximum to minimum done, and 81 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 3.30 million km2, 1.15 million km2 above the 2017 record low minimum of 2.15 million km2.
___________________________________________________________
N.B. Click on image  for full-size
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1575 on: December 04, 2020, 02:33:55 PM »
JAXA ANTARCTIC SEA ICE EXTENT:  13,569,347 KM2 as at 03-Dec-2020

- Extent loss on this day 165k, 24 k less than the average loss on this day (of the last 10 years) of 189k,
- Extent loss from maximum on this date is 5.29 million km2, 0.34 million km2, (6%) less than the 10 year average of 5.64 million km2.
- Extent is at position #32 in the satellite record of which 17 lower values are in the years before 2000

- Extent is  2,570 k MORE than 2016
- Extent is  1,300 k MORE than 2017
- Extent is  986 k MORE than 2018
- Extent is  1,308 k MORE than 2019
- Extent is  293 k MORE than the 1980's Average

- On average 35.5% of ice loss  from maximum to minimum done, and 80 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 3.32 million km2, 1.18 million km2 above the 2017 record low minimum of 2.15 million km2.
_____________________________________________________________
N.B. Click on image to enlarge
"Para a Causa do Povo a Luta Continua!"
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1576 on: December 05, 2020, 04:15:37 PM »
JAXA ANTARCTIC SEA ICE EXTENT:  13,399,576 KM2 as at 04-Dec-2020

- Extent loss on this day 170k, 39 k less than the average loss on this day (of the last 10 years) of 209k,
- Extent loss from maximum on this date is 5.46 million km2, 0.38 million km2, (6%) less than the 10 year average of 5.84 million km2.
- Extent is at position #33 in the satellite record of which 18 lower values are in the years before 2000

- Extent is  2,612 k MORE than 2016
- Extent is  1,279 k MORE than 2017
- Extent is  1,016 k MORE than 2018
- Extent is  1,391 k MORE than 2019
- Extent is  333 k MORE than the 1980's Average

- On average 36.8% of ice loss  from maximum to minimum done, and 79 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 3.36 million km2, 1.22 million km2 above the 2017 record low minimum of 2.15 million km2.
_______________________________________________________________
A below average sea ice loss results in extent dropping down one place to 33rd lowest.
_______________________________________________________________
N.B. Click on image to enlarge
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1577 on: December 06, 2020, 12:09:06 PM »
JAXA ANTARCTIC SEA ICE EXTENT:  13,172,971 KM2 as at 05-Dec-2020

- Extent loss on this day 227k, 37 k more than the average loss on this day (of the last 10 years) of 190k,
- Extent loss from maximum on this date is 5.69 million km2, 0.32 million km2, (5%) less than the 10 year average of 6.01 million km2.
- Extent is at position #32 in the satellite record of which 17 lower values are in the years before 2000

- Extent is  2,558 k MORE than 2016
- Extent is  1,215 k MORE than 2017
- Extent is  1,037 k MORE than 2018
- Extent is  1,405 k MORE than 2019
- Extent is  319 k MORE than the 1980's Average

- On average 37.9% of ice loss  from maximum to minimum done, and 78 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 3.33 million km2, 1.18 million km2 above the 2017 record low minimum of 2.15 million km2.
_______________________________________________________________
An above average sea ice loss results in extent rising up one place to 32nd lowest.
_______________________________________________________________
N.B. Click on image to enlarge
"Para a Causa do Povo a Luta Continua!"
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1578 on: December 07, 2020, 12:43:54 PM »
JAXA ANTARCTIC SEA ICE EXTENT:  12,976,456 KM2 as at 06-Dec-2020

- Extent loss on this day 197k, 38 k more than the average loss on this day (of the last 10 years) of 159k,
- Extent loss from maximum on this date is 5.88 million km2, 0.28 million km2, (5%) less than the 10 year average of 6.17 million km2.
- Extent is at position #32 in the satellite record of which 17 lower values are in the years before 2000

- Extent is  2,526 k MORE than 2016
- Extent is  1,244 k MORE than 2017
- Extent is  1,017 k MORE than 2018
- Extent is  1,414 k MORE than 2019
- Extent is  327 k MORE than the 1980's Average

- On average 38.9% of ice loss  from maximum to minimum done, and 77 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 3.29 million km2, 1.14 million km2 above the 2017 record low minimum of 2.15 million km2.
_______________________________________________________________
N.B. Click on image to enlarge
"Para a Causa do Povo a Luta Continua!"
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1579 on: December 08, 2020, 11:45:48 AM »
JAXA ANTARCTIC SEA ICE EXTENT:  12,766,209 KM2 as at 07-Dec-2020

- Extent loss on this day 210k, 27 k more than the average loss on this day (of the last 10 years) of 183k,
- Extent loss from maximum on this date is 6.09 million km2, 0.26 million km2, (4%) less than the 10 year average of 6.35 million km2.
- Extent is at position #31 in the satellite record of which 17 lower values are in the years before 2000

- Extent is  2,516 k MORE than 2016
- Extent is  1,226 k MORE than 2017
- Extent is  983 k MORE than 2018
- Extent is  1,419 k MORE than 2019
- Extent is  329 k MORE than the 1980's Average

- On average 40.0% of ice loss  from maximum to minimum done, and 76 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 3.26 million km2, 1.11 million km2 above the 2017 record low minimum of 2.15 million km2.
_______________________________________________________________
N.B. Click on image to enlarge
"Para a Causa do Povo a Luta Continua!"
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1580 on: December 09, 2020, 11:39:36 AM »
JAXA ANTARCTIC SEA ICE EXTENT:  12,537,752 KM2 as at 08-Dec-2020

- Extent loss on this day 228k, 17 k more than the average loss on this day (of the last 10 years) of 211k,
- Extent loss from maximum on this date is 6.32 million km2, 0.24 million km2, (4%) less than the 10 year average of 6.56 million km2.
- Extent is at position #31 in the satellite record of which 17 lower values are in the years before 2000

- Extent is  2,562 k MORE than 2016
- Extent is  1,239 k MORE than 2017
- Extent is  901 k MORE than 2018
- Extent is  1,465 k MORE than 2019
- Extent is  334 k MORE than the 1980's Average

- On average 41.4% of ice loss  from maximum to minimum done, and 75 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 3.24 million km2, 1.10 million km2 above the 2017 record low minimum of 2.15 million km2.
_______________________________________________________________
N.B. Click on image to enlarge
"Para a Causa do Povo a Luta Continua!"
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1581 on: December 10, 2020, 11:30:59 AM »
JAXA ANTARCTIC SEA ICE EXTENT:  12,316,944 KM2 as at 09-Dec-2020

- Extent loss on this day 221k, 7 k less than the average loss on this day (of the last 10 years) of 228k,
- Extent loss from maximum on this date is 6.54 million km2, 0.22 million km2, (3%) less than the 10 year average of 6.77 million km2.
- Extent is at position #31 in the satellite record of which 17 lower values are in the years before 2000

- Extent is  2,597 k MORE than 2016
- Extent is  1,244 k MORE than 2017
- Extent is  997 k MORE than 2018
- Extent is  1,528 k MORE than 2019
- Extent is  336 k MORE than the 1980's Average

- On average 42.7% of ice loss  from maximum to minimum done, and 74 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 3.25 million km2, 1.10 million km2 above the 2017 record low minimum of 2.15 million km2.
_______________________________________________________________
N.B. Click on image to enlarge
"Para a Causa do Povo a Luta Continua!"
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1582 on: December 11, 2020, 03:15:18 PM »
JAXA ANTARCTIC SEA ICE EXTENT:  12,125,061 KM2 as at 10-Dec-2020

- Extent loss on this day 192k, 70 k less than the average loss on this day (of the last 10 years) of 262k,
- Extent loss from maximum on this date is 6.74 million km2, 0.27 million km2, (4%) less than the 10 year average of 7.00 million km2.
- Extent is at position #32 in the satellite record of which 17 lower values are in the years before 2000

- Extent is  2,727 k MORE than 2016
- Extent is  1,278 k MORE than 2017
- Extent is  1,143 k MORE than 2018
- Extent is  1,647 k MORE than 2019
- Extent is  362 k MORE than the 1980's Average

- On average 44.3% of ice loss  from maximum to minimum done, and 73 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 3.32 million km2, 1.17 million km2 above the 2017 record low minimum of 2.15 million km2.
_______________________________________________________________
N.B. Click on image to enlarge
"Para a Causa do Povo a Luta Continua!"
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1583 on: December 12, 2020, 01:09:13 PM »
JAXA ANTARCTIC SEA ICE EXTENT:  11,942,952 KM2 as at 11-Dec-2020

- Extent loss on this day 182k, 70 k less than the average loss on this day (of the last 10 years) of 252k,
- Extent loss from maximum on this date is 6.92 million km2, 0.31 million km2, (4%) less than the 10 year average of 7.23 million km2.
- Extent is at position #32 in the satellite record of which 17 lower values are in the years before 2000

- Extent is  2,864 k MORE than 2016
- Extent is  1,353 k MORE than 2017
- Extent is  1,314 k MORE than 2018
- Extent is  1,705 k MORE than 2019
- Extent is  419 k MORE than the 1980's Average

- On average 45.8% of ice loss  from maximum to minimum done, and 72 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 3.39 million km2, 1.24 million km2 above the 2017 record low minimum of 2.15 million km2.
_______________________________________________________________
N.B. Click on image to enlarge
"Para a Causa do Povo a Luta Continua!"
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Stephan

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Re: Sea Ice Extent around Antarctica
« Reply #1584 on: December 12, 2020, 08:57:22 PM »
Antarctic Ice Ectent is larger than any of the four decadal averages...
It is too late just to be concerned about Climate Change

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Re: Sea Ice Extent around Antarctica
« Reply #1585 on: December 12, 2020, 09:35:33 PM »
Antarctic Ice Extent is larger than any of the four decadal averages...
Increased glacier melt causes  a larger fresher surface water layer around Antarctica. This fresher surface water freezes easier. With open ocean on all sides this surface layer needs to be continuously refreshed to keep salinity low around ice edges. With increased distance from antarctica ocean depth increases. In a complex way the greater ice extent around Antarctica at this time indicates greater melt is occurring in the region.

The arctic is different it is more like a bathtub three sides are nearly land locked. The fourth side is relatively shallow, except the Fram strait, and the deepest ocean is in the basin. Increase in glacier melt adds fresh water but it mostly makes the fresh water layer deeper rather expanding extent. Since freshwater layer was always below the ice it does not show up much in extent. The increase does cause changes in currents and other effects.
I find it interesting that the poles are almost exactly the opposite in geography. The Arctic being a mostly land locked hole and the Antarctic being an island rising from deep ocean. Circulation from cold pole to cold pole would not occur if it was made any other way.

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Re: Sea Ice Extent around Antarctica
« Reply #1586 on: December 12, 2020, 09:58:50 PM »
Antarctic Ice Extent is larger than any of the four decadal averages...
Increased glacier melt causes  a larger fresher surface water layer around Antarctica. This fresher surface water freezes easier. With open ocean on all sides this surface layer needs to be continuously refreshed to keep salinity low around ice edges. With increased distance from antarctica ocean depth increases. In a complex way the greater ice extent around Antarctica at this time indicates greater melt is occurring in the region.

That may be true in west Antarctica.  In East Antarctica, the story is a bit different.  Increased snowfall has resulted in increasing glacial mass, and consequently, sea ice.

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Re: Sea Ice Extent around Antarctica
« Reply #1587 on: December 12, 2020, 10:03:09 PM »
But what actually drives the extent and how relevant is actual extent?

Persistent polynya are more interesting in the short term.

BTW. This is a actual question. I have never given it that much thought since the Arctic part is so much more relevant.

More heat in the atmosphere means more heat going there so essentially more snow dumped so more run off but how relevant is that for extant. Probably a bit because every surface ice can freeze from helps so more icebergs and debris is more seeding.

If i had to blind guess it antarctic SIE should be up for decades.



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Re: Sea Ice Extent around Antarctica
« Reply #1588 on: December 12, 2020, 11:16:57 PM »
I think my point is that SIE around Antarctica isn't very important globally but it is much more important globally around the Arctic. In the Antarctic there is no discernable trend. The lowest high was 2002 (I think) but the highest was 2014 then 2017 had a pretty low high. If their is a trend it is that the extent in Antarctica is more extreme high and low in recent years than it used to be. Where the Arctic has been breaking more low extent records as the years pass.
Without an explanation though it sounds like cherry picking data. In either case volume is more important than extent IMO though I do not recall having seen any Antarctic ice volume graphs. Since most of the ice in Antarctica is in the glaciers I am not sure it would be all that informative. I suspect sea ice around Antarctica melts almost completely every year. Though from satellites it is pretty hard to tell the difference without tracking each piece. Where would land fast ice fit into the picture. Physically it is sea ice but if it is old enough it becomes more like glacier ice and can be harder to distinguish because of its location.


If I had to guess it will continue to get more extreme as the years pass. I am probably wrong but there may be a pattern of more Antarctic extent a year or so after extreme heat in the arctic. The ice edge is roughly a circle the further out it gets the more fresh water required per meter of radius expansion. As the ice edge gets to deeper water the fresh water has more volume to dilute it and currents are more likely to disperse it.  The ocean is also warming. So this years el nino may be a la nina in a decade.

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Re: Sea Ice Extent around Antarctica
« Reply #1589 on: December 13, 2020, 09:42:13 AM »
Quote
That may be true in west Antarctica.  In East Antarctica, the story is a bit different.  Increased snowfall has resulted in increasing glacial mass, and consequently, sea ice.
Such certainty with no support given on a scientific blog .
As usual from one of our resident .....

https://www.pnas.org/content/116/4/1095
Four decades of Antarctic Ice Sheet mass balance from 1979–2017
 View ORCID ProfileEric Rignot,  View ORCID ProfileJérémie Mouginot, Bernd Scheuchl,  View ORCID ProfileMichiel van den Broeke, Melchior J. van Wessem, and  View ORCID ProfileMathieu Morlighem
PNAS January 22, 2019
Abstract
Quote
We use updated drainage inventory, ice thickness, and ice velocity data to calculate the grounding line ice discharge of 176 basins draining the Antarctic Ice Sheet from 1979 to 2017. We compare the results with a surface mass balance model to deduce the ice sheet mass balance. The total mass loss increased from 40 ± 9 Gt/y in 1979–1990 to 50 ± 14 Gt/y in 1989–2000, 166 ± 18 Gt/y in 1999–2009, and 252 ± 26 Gt/y in 2009–2017. In 2009–2017, the mass loss was dominated by the Amundsen/Bellingshausen Sea sectors, in West Antarctica (159 ± 8 Gt/y), Wilkes Land, in East Antarctica (51 ± 13 Gt/y), and West and Northeast Peninsula (42 ± 5 Gt/y). The contribution to sea-level rise from Antarctica averaged 3.6 ± 0.5 mm per decade with a cumulative 14.0 ± 2.0 mm since 1979, including 6.9 ± 0.6 mm from West Antarctica, 4.4 ± 0.9 mm from East Antarctica, and 2.5 ± 0.4 mm from the Peninsula (i.e., East Antarctica is a major participant in the mass loss). During the entire period, the mass loss concentrated in areas closest to warm, salty, subsurface, circumpolar deep water (CDW), that is, consistent with enhanced polar westerlies pushing CDW toward Antarctica to melt its floating ice shelves, destabilize the glaciers, and raise sea level.

This is one of many papers that attempt to quantify mass balance of the Antarctic. Other papers come to different conclusions.
I do not know... sorry We do not not for 100% certainty what is happening with the east antarctic land ice mass balance .
Most actual experts seem to have the opinion that it is probably not good for the future of land ice in any region of the antarctic.

Seasonal Antarctic Sea ice extent .
https://www.nap.edu/read/24696/chapter/2
The consensus seems to be..  Sea ice extent around Antarctica  is more dependent on natural variations in wind and currents than land ice mass balance with perhaps the human caused Antarctic ozone hole also having a role .

 
 

 
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1590 on: December 13, 2020, 12:17:18 PM »
JAXA ANTARCTIC SEA ICE EXTENT:  11,729,429 KM2 as at 12-Dec-2020

- Extent loss on this day 214k, 8 k less than the average loss on this day (of the last 10 years) of 222k,
- Extent loss from maximum on this date is 7.13 million km2, 0.30 million km2, (4%) less than the 10 year average of 7.44 million km2.
- Extent is at position #32 in the satellite record of which 17 lower values are in the years before 2000

- Extent is  2,960 k MORE than 2016
- Extent is  1,398 k MORE than 2017
- Extent is  1,321 k MORE than 2018
- Extent is  1,751 k MORE than 2019
- Extent is  402 k MORE than the 1980's Average

- On average 47.2% of ice loss  from maximum to minimum done, and 71 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 3.40 million km2, 1.25 million km2 above the 2017 record low minimum of 2.15 million km2.
_______________________________________________________________
N.B. Click on image to enlarge
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1591 on: December 13, 2020, 01:21:12 PM »
Antarctic Ice Extent is larger than any of the four decadal averages...
Increased glacier melt causes  a larger fresher surface water layer around Antarctica. This fresher surface water freezes easier. With open ocean on all sides this surface layer needs to be continuously refreshed to keep salinity low around ice edges. With increased distance from antarctica ocean depth increases. In a complex way the greater ice extent around Antarctica at this time indicates greater melt is occurring in the region.
That may be true in West Antarctica.  In East Antarctica, the story is a bit different.  Increased snowfall has resulted in increasing glacial mass, and consequently, sea ice.
None of the posts above or the remarks below really explains the massive sea ice changes since 2007 illustrated by the first image attached

GRACE-FO is the best source of AIS mass changes since 2002 @ http://gravis.gfz-potsdam.de/antarctica. I attach map and graphs of cumulative mass change since 2002 by region.

The story of East Antarctica is also changing, with some parts already in mass loss.

As regards snowfall, to quote one of the papers I looked at "The remote and cold Antarctic continent presents unique challenges to quantify precipitation rates from space and in situ observations. This has resulted in large uncertainties in current estimates."

I have seen a paper that says snowfall on Antarctica has increased by 10% in the last 200 years, and another that says increased Antarctic precipitation has slowed sea level rise in the 20th century. Elsewhere I read that in recent years there is no discernible trend. The treatment of snowfall in the spreadsheet attached to https://www.pnas.org/content/116/4/1095
Four decades of Antarctic Ice Sheet mass balance from 1979–2017
is the least satisfactory part of the paper.

Conclusion - a lot of don't knows because we don't have the data.
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The Walrus

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Re: Sea Ice Extent around Antarctica
« Reply #1592 on: December 13, 2020, 02:09:14 PM »
As requested:

“Most scientists agree that East Antarctica is gaining mass in the form of increased snowfall, ice, or both.”

https://www.scientificamerican.com/article/what-to-believe-in-antarctica-rsquo-s-great-ice-debate/

I fail to see why every post containing common knowledge must be referenced.  Must I include a reference to a statement that sea level is rising?

<Don't make false analogies.
You originally wrote: "In East Antarctica, the story is a bit different.  Increased snowfall has resulted in increasing glacial mass, and consequently, sea ice."
Most scientists agree with the first part (glacial mass), but not all, as there isn't enough data. This is not the same certainty and common knowledge as rising sea levels. So yes, best to support such claims, though not a must in every post.
For your second part (increasing sea ice as a consequence of increasing glacial mass and/or snowfall), I doubt you can find references for it, and I doubt it's true, though I stand ready to be corrected. And yet, the second part is the part that is relevant and on topic here. I probably should not have let it pass as posted. O>
« Last Edit: December 14, 2020, 01:01:01 PM by oren »

gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1593 on: December 13, 2020, 03:54:49 PM »
Antarctic SeaIce NSIDC data

Looking at NSIDC Area & Extent data just causes more confusion.

Extent is 11th HIGHEST in the satellite record, and well above the 2010's average.
Area    is 28th HIGHEST in the satellite record, and well BELOW the 2010's average.

This shows up well in the concentration data - 3rd lowest in the satellite record, and graph (attached)

Probably will be a good idea to see in which seas this is showing up most.
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1594 on: December 13, 2020, 06:38:26 PM »
NSIDC Concentration
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FredBear

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Re: Sea Ice Extent around Antarctica
« Reply #1595 on: December 13, 2020, 11:28:26 PM »
That third graph from gerontocrat (reply 1592) looks like trouble brewing?
Earlier in the melt season new thin ice forms in any newly-opened waters near the coast and gets blown out towards the southern edge of the old sea ice drifting northward. This helps keep the ice extent and area up but now there is very little ice being formed like this so there is no replacement for the melting ice.
As area declines rapidly that implies that melting is reducing albedo so that less short-wave radiation is being reflected back to space and the melt feedback loop which we fear in the Arctic is occurring in Antarctica too    .     .    .    and extent will probably follow concentration off the cliff!
« Last Edit: December 14, 2020, 08:18:53 AM by FredBear »

gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1596 on: December 14, 2020, 12:10:39 PM »
JAXA ANTARCTIC SEA ICE EXTENT:  11,486,261 KM2 as at 13-Dec-2020

- Extent loss on this day 243k, 15 k more than the average loss on this day (of the last 10 years) of 228k,
- Extent loss from maximum on this date is 7.37 million km2, 0.27 million km2, (4%) less than the 10 year average of 7.64 million km2.
- Extent is at position #32 in the satellite record of which 17 lower values are in the years before 2000

- Extent is  2,967 k MORE than 2016
- Extent is  1,411 k MORE than 2017
- Extent is  1,355 k MORE than 2018
- Extent is  1,709 k MORE than 2019
- Extent is  366 k MORE than the 1980's Average

- On average 48.5% of ice loss  from maximum to minimum done, and 70 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 3.38 million km2, 1.24 million km2 above the 2017 record low minimum of 2.15 million km2.
_______________________________________________________________
N.B. Click on image to enlarge
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gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1597 on: December 15, 2020, 12:13:18 PM »
JAXA ANTARCTIC SEA ICE EXTENT:  11,214,792 KM2 as at 14-Dec-2020

- Extent loss on this day 271k, 55 k more than the average loss on this day (of the last 10 years) of 216k,
- Extent loss from maximum on this date is 7.65 million km2, 0.19 million km2, (2%) less than the 10 year average of 7.84 million km2.
- Extent is at position #32 in the satellite record of which 17 lower values are in the years before 2000

- Extent is  2,936 k MORE than 2016
- Extent is  1,373 k MORE than 2017
- Extent is  1,398 k MORE than 2018
- Extent is  1,677 k MORE than 2019
- Extent is  303 k MORE than the 1980's Average

- On average 49.8% of ice loss  from maximum to minimum done, and 69 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 3.33 million km2, 1.18 million km2 above the 2017 record low minimum of 2.15 million km2.
_______________________________________________________________
N.B. Click on image to enlarge
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The Walrus

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Re: Sea Ice Extent around Antarctica
« Reply #1598 on: December 15, 2020, 02:34:55 PM »
But what actually drives the extent and how relevant is actual extent?

Persistent polynya are more interesting in the short term.

BTW. This is a actual question. I have never given it that much thought since the Arctic part is so much more relevant.

More heat in the atmosphere means more heat going there so essentially more snow dumped so more run off but how relevant is that for extant. Probably a bit because every surface ice can freeze from helps so more icebergs and debris is more seeding.

If i had to blind guess it antarctic SIE should be up for decades.

"An increase in the extent of polynyas in the Ross Sea from 1978 to 2008 contributed to sea ice production." 
 
http://www.antarcticglaciers.org/glaciers-and-climate/antarctic-sea-ice/#:~:text=The%20Arctic%20regularly%20reaches%20ever,a%20record%20for%20maximum%20extent.

Additionally, sea ice extent has increased over most of East Antarctica, while decreases have occurred in the Bellingshausen and Amundsen seas of West Antarctica.  The Wendell Sea has had a decrease in winter sea expansion, but also a decrease in summer ice loss.

gerontocrat

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Re: Sea Ice Extent around Antarctica
« Reply #1599 on: December 16, 2020, 10:37:50 AM »
JAXA ANTARCTIC SEA ICE EXTENT:  10,997,592 KM2 as at 15-Dec-2020

- Extent loss on this day 217k, 3 k less than the average loss on this day (of the last 10 years) of 220k,
- Extent loss from maximum on this date is 7.86 million km2, 0.19 million km2, (2%) less than the 10 year average of 8.05 million km2.
- Extent is at position #32 in the satellite record of which 17 lower values are in the years before 2000

- Extent is  2,950 k MORE than 2016
- Extent is  1,443 k MORE than 2017
- Extent is  1,454 k MORE than 2018
- Extent is  1,677 k MORE than 2019
- Extent is  305 k MORE than the 1980's Average

- On average 51.2% of ice loss  from maximum to minimum done, and 68 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 3.33 million km2, 1.18 million km2 above the 2017 record low minimum of 2.15 million km2.
_______________________________________________________________
N.B. Click on image to enlarge
"Para a Causa do Povo a Luta Continua!"
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"Damn, I wanted to see what happened next" (Epitaph)