Sea Ice Extent around Antarctica

[gerontocrat]

JAXA ANTARCTIC SEA ICE EXTENT:  3,016,350 KM2 as at 26-Feb-2021

- Extent gain on this day 116k, 96 k more than the average gain on this day (of the last 10 years) of 20k,
- Extent gain from minimum on this date is 0.23 million km2, 0.12 million km2, (118.4%) more than the 10 year average of 0.10 million km2.
- Extent is at position #28 in the satellite record of which 15 lower values are in the years before 2000

- Extent is  713 k LESS than 2015
- Extent is  856 k MORE than 2017
- Extent is  494 k MORE than 2006
- Extent is  204 k MORE than 2020
- Extent is  158 k MORE than the 1980's Average

- On average  1.4% of ice gain from minimum to maximum done, and 206 days to maximum

Projections. (Table JAXA-Ant1)

Average remaining freeze (of the last 10 years) would produce a maximum in Sept 2020 of 18.89 million km2, 0.83 million km2 above the 2017 record low maximum of 18.06 million km2.
___________________________________________________________
N.B. Click on image  for full-size

[gerontocrat]

JAXA ANTARCTIC SEA ICE EXTENT:  3,092,800 KM2 as at 27-Feb-2021

- Extent gain on this day 76k, 53 k more than the average gain on this day (of the last 10 years) of 23k,
- Extent gain from minimum on this date is 0.31 million km2, 0.18 million km2, (139.2%) more than the 10 year average of 0.13 million km2.
- Extent is at position #30 in the satellite record of which 17 lower values are in the years before 2000

- Extent is  679 k LESS than 2015
- Extent is  940 k MORE than 2017
- Extent is  543 k MORE than 2006
- Extent is  284 k MORE than 2020
- Extent is  203 k MORE than the 1980's Average

- On average  1.9% of ice gain from minimum to maximum done, and 205 days to maximum

Projections. (Table JAXA-Ant1)

Average remaining freeze (of the last 10 years) would produce a maximum in Sept 2020 of 18.95 million km2, 0.88 million km2 above the 2017 record low maximum of 18.06 million km2.
___________________________________________________________
In the last 3 days daily extent gain has been well above average, with the result that extent has moved from 19th lowest to 30th lowest in the satellite record in those 3 days.
___________________________________________________________
N.B. Click on image  for full-size

[gerontocrat]

JAXA ANTARCTIC SEA ICE EXTENT:  3,197,871 KM2 as at 28-Feb-2021

- Extent gain on this day 105k, 84 k more than the average gain on this day (of the last 10 years) of 21k,
- Extent gain from minimum on this date is 0.41 million km2, 0.26 million km2, (175.3%) more than the 10 year average of 0.15 million km2.
- Extent is at position #33 in the satellite record of which 19 lower values are in the years before 2000

- Extent is  603 k LESS than 2015
- Extent is  1,046 k MORE than 2017
- Extent is  634 k MORE than 2006
- Extent is  412 k MORE than 2020
- Extent is  270 k MORE than the 1980's Average

- On average  2.6% of ice gain from minimum to maximum done, and 204 days to maximum

Projections. (Table JAXA-Ant1)

Average remaining freeze (of the last 10 years) would produce a maximum in Sept 2020 of 19.03 million km2, 0.97 million km2 above the 2017 record low maximum of 18.06 million km2.
___________________________________________________________
In the last 4 days daily extent gain has been well above average, with the result that extent has moved from 19th lowest to 33rd lowest in the satellite record in those 4 days.
___________________________________________________________
N.B. Click on image  for full-size

[gerontocrat]

JAXA Data - a bit more

The Feb monthly average graph is attached. At 3.00 million km2, the Feb 21 average is just 83k below the (meaningless) linear trend, and just 40k below the simple monthly average from 1979 to 2021.

I also attach the 365 day trailing average graph and table. In February, the average briefly flirted with a daily reduction, but is now heading back up. It is currently just 47k less than the simple average of daily extents from 1979 to 2021.

Click on image  for full-size

[gerontocrat]

JAXA ANTARCTIC SEA ICE EXTENT:  3,336,462 KM2 as at 01-Mar-2021

- Extent gain on this day 139k, 114 k more than the average gain on this day (of the last 10 years) of 25k,
- Extent gain from minimum on this date is 0.55 million km2, 0.37 million km2, (214.9%) more than the 10 year average of 0.17 million km2.
- Extent is at position #33 in the satellite record of which 19 lower values are in the years before 2000

- Extent is  471 k LESS than 2015
- Extent is  1,189 k MORE than 2017
- Extent is  780 k MORE than 2006
- Extent is  556 k MORE than 2020
- Extent is  356 k MORE than the 1980's Average

- On average  3.4% of ice gain from minimum to maximum done, and 203 days to maximum

Projections. (Table JAXA-Ant1)

Average remaining freeze (of the last 10 years) would produce a maximum in Sept 2020 of 19.14 million km2, 1.08 million km2 above the 2017 record low maximum of 18.06 million km2.
___________________________________________________________
Click on image  for full-size

[gerontocrat]

JAXA ANTARCTIC SEA ICE EXTENT:  3,474,391 KM2 as at 02-Mar-2021

- Extent gain on this day 138k, 105 k more than the average gain on this day (of the last 10 years) of 33k,
- Extent gain from minimum on this date is 0.69 million km2, 0.48 million km2, (230.6%) more than the 10 year average of 0.21 million km2.
- Extent is at position #34 in the satellite record of which 19 lower values are in the years before 2000

- Extent is  329 k LESS than 2015
- Extent is  1,325 k MORE than 2017
- Extent is  944 k MORE than 2006
- Extent is  657 k MORE than 2020
- Extent is  440 k MORE than the 1980's Average

- On average  4.3% of ice gain from minimum to maximum done, and 202 days to maximum

Projections. (Table JAXA-Ant1)

Average remaining freeze (of the last 10 years) would produce a maximum in Sept 2020 of 19.25 million km2, 1.18 million km2 above the 2017 record low maximum of 18.06 million km2.
___________________________________________________________
In the last 5 days daily extent gain has been impressively above average, with the result that extent has moved from 19th lowest to 34th lowest (10th highest) in the satellite record in those 5 days.
___________________________________________________________
Click on image  for full-size

[oren]

The last few days have been quite the event for this time of year, statistically speaking.

[gerontocrat]

JAXA ANTARCTIC SEA ICE EXTENT:  3,582,621 KM2 as at 03-Mar-2021

- Extent gain on this day 108k, 61 k more than the average gain on this day (of the last 10 years) of 47k,
- Extent gain from minimum on this date is 0.79 million km2, 0.54 million km2, (211.8%) more than the 10 year average of 0.25 million km2.
- Extent is at position #35 in the satellite record of which 20 lower values are in the years before 2000

- Extent is  309 k LESS than 2015
- Extent is  1,423 k MORE than 2017
- Extent is  1,055 k MORE than 2006
- Extent is  704 k MORE than 2020
- Extent is  492 k MORE than the 1980's Average

- On average  5.0% of ice gain from minimum to maximum done, and 201 days to maximum

Projections. (Table JAXA-Ant1)

Average remaining freeze (of the last 10 years) would produce a maximum in Sept 2020 of 19.31 million km2, 1.25 million km2 above the 2017 record low maximum of 18.06 million km2.
___________________________________________________________
The last 7 days average daily gain is 108k, 4 times the 10 years average daily gain for this period. Extent is now 35th lowest, i.e. 9th highest, in the satellite record.
___________________________________________________________
Click on image  for full-size

[gerontocrat]

JAXA ANTARCTIC SEA ICE EXTENT:  3,766,609 KM2 as at 04-Mar-2021

- Extent gain on this day 184k, 130 k more than the average gain on this day (of the last 10 years) of 54k,
- Extent gain from minimum on this date is 0.98 million km2, 0.67 million km2, (216.9%) more than the 10 year average of 0.31 million km2.
- Extent is at position #36 in the satellite record of which 20 lower values are in the years before 2000

- Extent is  276 k LESS than 2015
- Extent is  1,598 k MORE than 2017
- Extent is  1,193 k MORE than 2006
- Extent is  827 k MORE than 2020
- Extent is  628 k MORE than the 1980's Average

- On average  6.1% of ice gain from minimum to maximum done, and 200 days to maximum

Projections. (Table JAXA-Ant1)

Average remaining freeze (of the last 10 years) would produce a maximum in Sept 2020 of 19.44 million km2, 1.38 million km2 above the 2017 record low maximum of 18.06 million km2.
___________________________________________________________
The very unusual daily extent gains for this time of year continue. 184k on this day makes a total gain of 943k in the last 8 days, extent that was 19th lowest 8 days ago now 36th lowest (i.e. 8th highest) in the satellite record.
___________________________________________________________
Click on image  for full-size

[gerontocrat]

JAXA ANTARCTIC SEA ICE EXTENT:  3,832,046 KM2 as at 05-Mar-2021

- Extent gain on this day 65k, 9 k more than the average gain on this day (of the last 10 years) of 56k,
- Extent gain from minimum on this date is 1.04 million km2, 0.68 million km2, (186.0%) more than the 10 year average of 0.37 million km2.
- Extent is at position #37 in the satellite record of which 20 lower values are in the years before 2000

- Extent is  289 k LESS than 2015
- Extent is  1,645 k MORE than 2017
- Extent is  1,199 k MORE than 2006
- Extent is  786 k MORE than 2020
- Extent is  638 k MORE than the 1980's Average

- On average  6.5% of ice gain from minimum to maximum done, and 199 days to maximum

Projections. (Table JAXA-Ant1)

Average remaining freeze (of the last 10 years) would produce a maximum in Sept 2020 of 19.45 million km2, 1.38 million km2 above the 2017 record low maximum of 18.06 million km2.
___________________________________________________________
Daily gain reduces to close to but above average. Extent now 37th lowest, 7th highest in the satellite record.
___________________________________________________________
Click on image  for full-size

[gerontocrat]

Antarctic - what's going on - some clues from NSIDC data

The extreme increases in Antarctic sea ice extent were not matched by such extreme increases in Antarctic sea ice area. You can see this from the Antarctic concentration graph (1st image).

Most of the large recent increases were in the Ross sea - in both sea ice area and extent, though for most of February ice concentration in the Ross sea was at a record low.

Next post looks at the Weddell Sea

click images to enlarge

[gerontocrat]

Antarctic - what's going on - some clues from NSIDC data

The Weddell Sea is the largest sea surrounding Antarctica.
It has not shown any large variation from the average, except to maintain a low ice concentration.

I also attach a map for those unfamiliar with the Antarctic Seas.






click images to enlarge

[gerontocrat]

It has been somewhat cold in the Ross Sea and looks like staying that way.

[gerontocrat]

JAXA ANTARCTIC SEA ICE EXTENT:  3,893,971 KM2 as at 06-Mar-2021

- Extent gain on this day 62k, 2 k more than the average gain on this day (of the last 10 years) of 60k,
- Extent gain from minimum on this date is 1.11 million km2, 0.68 million km2, (160.0%) more than the 10 year average of 0.43 million km2.
- Extent is at position #37 in the satellite record of which 20 lower values are in the years before 2000

- Extent is  267 k LESS than 2015
- Extent is  1,696 k MORE than 2017
- Extent is  1,212 k MORE than 2006
- Extent is  714 k MORE than 2020
- Extent is  655 k MORE than the 1980's Average

- On average  6.9% of ice gain from minimum to maximum done, and 198 days to maximum

Projections. (Table JAXA-Ant1)

Average remaining freeze (of the last 10 years) would produce a maximum in Sept 2020 of 19.45 million km2, 1.39 million km2 above the 2017 record low maximum of 18.06 million km2.
___________________________________________________________
Click on image  for full-size

[gerontocrat]

JAXA ANTARCTIC SEA ICE EXTENT:  3,948,614 KM2 as at 07-Mar-2021

- Extent gain on this day 55k, 13 k less than the average gain on this day (of the last 10 years) of 68k,
- Extent gain from minimum on this date is 1.16 million km2, 0.67 million km2, (135.2%) more than the 10 year average of 0.49 million km2.
- Extent is at position #37 in the satellite record of which 20 lower values are in the years before 2000

- Extent is  248 k LESS than 2015
- Extent is  1,704 k MORE than 2017
- Extent is  1,213 k MORE than 2006
- Extent is  640 k MORE than 2020
- Extent is  665 k MORE than the 1980's Average

- On average  7.3% of ice gain from minimum to maximum done, and 197 days to maximum

Projections. (Table JAXA-Ant1)

Average remaining freeze (of the last 10 years) would produce a maximum in Sept 2020 of 19.44 million km2, 1.37 million km2 above the 2017 record low maximum of 18.06 million km2.
___________________________________________________________
Click on image  for full-size

[gerontocrat]

JAXA ANTARCTIC SEA ICE EXTENT:  4,016,883 KM2 as at 08-Mar-2021

- Extent gain on this day 68k, 2 k less than the average gain on this day (of the last 10 years) of 70k,
- Extent gain from minimum on this date is 1.23 million km2, 0.67 million km2, (118.2%) more than the 10 year average of 0.56 million km2.
- Extent is at position #37 in the satellite record of which 20 lower values are in the years before 2000

- Extent is  229 k LESS than 2015
- Extent is  1,695 k MORE than 2017
- Extent is  1,221 k MORE than 2006
- Extent is  599 k MORE than 2020
- Extent is  690 k MORE than the 1980's Average

- On average  7.7% of ice gain from minimum to maximum done, and 196 days to maximum

Projections. (Table JAXA-Ant1)

Average remaining freeze (of the last 10 years) would produce a maximum in Sept 2020 of 19.43 million km2, 1.37 million km2 above the 2017 record low maximum of 18.06 million km2.
___________________________________________________________
Click on image  for full-size

[Stephan]

Thanks again gero for keeping us up to date. Day by day.

It appears to me that the increase rate of Antarctic Sea Ice Extent has found its way back to normal, but the extent now is at a much higher level.

[gerontocrat]

JAXA ANTARCTIC SEA ICE EXTENT:  4,081,606 KM2 as at 09-Mar-2021

- Extent gain on this day 65k, 14 k less than the average gain on this day (of the last 10 years) of 79k,
- Extent gain from minimum on this date is 1.29 million km2, 0.65 million km2, (101.6%) more than the 10 year average of 0.64 million km2.
- Extent is at position #37 in the satellite record of which 20 lower values are in the years before 2000

- Extent is  221 k LESS than 2015
- Extent is  1,693 k MORE than 2017
- Extent is  1,240 k MORE than 2006
- Extent is  595 k MORE than 2020
- Extent is  708 k MORE than the 1980's Average

- On average  8.1% of ice gain from minimum to maximum done, and 195 days to maximum

Projections. (Table JAXA-Ant1)

Average remaining freeze (of the last 10 years) would produce a maximum in Sept 2020 of 19.42 million km2, 1.36 million km2 above the 2017 record low maximum of 18.06 million km2.
___________________________________________________________
Click on image  for full-size

[gerontocrat]

JAXA ANTARCTIC SEA ICE EXTENT:  4,120,632 KM2 as at 10-Mar-2021

- Extent gain on this day 39k, 27 k less than the average gain on this day (of the last 10 years) of 66k,
- Extent gain from minimum on this date is 1.33 million km2, 0.63 million km2, (88.4%) more than the 10 year average of 0.71 million km2.
- Extent is at position #37 in the satellite record of which 20 lower values are in the years before 2000

- Extent is  238 k LESS than 2015
- Extent is  1,692 k MORE than 2017
- Extent is  1,276 k MORE than 2006
- Extent is  574 k MORE than 2020
- Extent is  691 k MORE than the 1980's Average

- On average  8.3% of ice gain from minimum to maximum done, and 194 days to maximum

Projections. (Table JAXA-Ant1)

Average remaining freeze (of the last 10 years) would produce a maximum in Sept 2020 of 19.39 million km2, 1.33 million km2 above the 2017 record low maximum of 18.06 million km2.
___________________________________________________________
Click on image  for full-size

[gerontocrat]

JAXA ANTARCTIC SEA ICE EXTENT:  4,192,743 KM2 as at 11-Mar-2021

- Extent gain on this day 72k, 4 k less than the average gain on this day (of the last 10 years) of 76k,
- Extent gain from minimum on this date is 1.41 million km2, 0.62 million km2, (79.2%) more than the 10 year average of 0.78 million km2.
- Extent is at position #37 in the satellite record of which 20 lower values are in the years before 2000

- Extent is  276 k LESS than 2015
- Extent is  1,714 k MORE than 2017
- Extent is  1,325 k MORE than 2006
- Extent is  568 k MORE than 2020
- Extent is  688 k MORE than the 1980's Average

- On average  8.8% of ice gain from minimum to maximum done, and 193 days to maximum

Projections. (Table JAXA-Ant1)

Average remaining freeze (of the last 10 years) would produce a maximum in Sept 2020 of 19.39 million km2, 1.33 million km2 above the 2017 record low maximum of 18.06 million km2.
___________________________________________________________
Click on image  for full-size

[gerontocrat]

JAXA ANTARCTIC SEA ICE EXTENT:  4,265,462 KM2 as at 12-Mar-2021

- Extent gain on this day 73k, 10 k less than the average gain on this day (of the last 10 years) of 83k,
- Extent gain from minimum on this date is 1.48 million km2, 0.61 million km2, (70.5%) more than the 10 year average of 0.87 million km2.
- Extent is at position #37 in the satellite record of which 20 lower values are in the years before 2000

- Extent is  263 k LESS than 2015
- Extent is  1,744 k MORE than 2017
- Extent is  1,345 k MORE than 2006
- Extent is  543 k MORE than 2020
- Extent is  682 k MORE than the 1980's Average

- On average  9.2% of ice gain from minimum to maximum done, and 192 days to maximum

Projections. (Table JAXA-Ant1)

Average remaining freeze (of the last 10 years) would produce a maximum in Sept 2020 of 19.38 million km2, 1.32 million km2 above the 2017 record low maximum of 18.06 million km2.
___________________________________________________________
Click on image  for full-size

[gerontocrat]

JAXA ANTARCTIC SEA ICE EXTENT:  4,297,516 KM2 as at 13-Mar-2021

- Extent gain on this day 32k, 49 k less than the average gain on this day (of the last 10 years) of 81k,
- Extent gain from minimum on this date is 1.51 million km2, 0.56 million km2, (59.4%) more than the 10 year average of 0.95 million km2.
- Extent is at position #34 in the satellite record of which 19 lower values are in the years before 2000

- Extent is  336 k LESS than 2015
- Extent is  1,742 k MORE than 2017
- Extent is  1,373 k MORE than 2006
- Extent is  492 k MORE than 2020
- Extent is  644 k MORE than the 1980's Average

- On average  9.4% of ice gain from minimum to maximum done, and 191 days to maximum

Projections. (Table JAXA-Ant1)

Average remaining freeze (of the last 10 years) would produce a maximum in Sept 2020 of 19.33 million km2, 1.27 million km2 above the 2017 record low maximum of 18.06 million km2.
___________________________________________________________
Below average extent gains in the last few days eventually result on the this day with extent changing from 37th to 34th lowest in the satellite record.
___________________________________________________________
Click on image  for full-size

[gerontocrat]

JAXA ANTARCTIC SEA ICE EXTENT:  4,347,559 KM2 as at 14-Mar-2021

- Extent gain on this day 50k, 23 k less than the average gain on this day (of the last 10 years) of 73k,
- Extent gain from minimum on this date is 1.56 million km2, 0.54 million km2, (52.9%) more than the 10 year average of 1.02 million km2.
- Extent is at position #34 in the satellite record of which 19 lower values are in the years before 2000

- Extent is  378 k LESS than 2015
- Extent is  1,732 k MORE than 2017
- Extent is  1,426 k MORE than 2006
- Extent is  433 k MORE than 2020
- Extent is  630 k MORE than the 1980's Average

- On average  9.8% of ice gain from minimum to maximum done, and 190 days to maximum

Projections. (Table JAXA-Ant1)

Average remaining freeze (of the last 10 years) would produce a maximum in Sept 2020 of 19.31 million km2, 1.25 million km2 above the 2017 record low maximum of 18.06 million km2.
___________________________________________________________
Click on image  for full-size

[gerontocrat]

JAXA ANTARCTIC SEA ICE EXTENT:  4,393,514 KM2 as at 15-Mar-2021

- Extent gain on this day 46k, 18 k less than the average gain on this day (of the last 10 years) of 64k,
- Extent gain from minimum on this date is 1.61 million km2, 0.52 million km2, (48.2%) more than the 10 year average of 1.08 million km2.
- Extent is 34th lowest in the satellite record of which 19 lower values are in the years before 2000

- Extent is  430 k LESS than 2015
- Extent is  1,719 k MORE than 2017
- Extent is  1,442 k MORE than 2006
- Extent is  395 k MORE than 2020
- Extent is  603 k MORE than the 1980's Average

- On average  10.0% of ice gain from minimum to maximum done, and 189 days to maximum

Projections. (Table JAXA-Ant1)

Average remaining freeze (of the last 10 years) would produce a maximum in Sept 2020 of 19.29 million km2, 1.23 million km2 above the 2017 record low maximum of 18.06 million km2.
___________________________________________________________
Click on image  for full-size

[gerontocrat]

JAXA Antarctic Sea Ice Extent - 365 day trailing average

The 365 day trailing average is now just 22k short of the long-term (42 years) average of 11.606 million km2.

This is after the vast increase in extent in 2014-15 and the equally large collapse in 2016-17.

I have read papers on why it went up, and papers on why it went down, but I have not seen any convincing explanation of the reasons for this huge up and down change that is totally outside any event before this in the satellite record.

Perhaps because it is still a mystery to science ?

[gerontocrat]

JAXA ANTARCTIC SEA ICE EXTENT:  4,448,113 KM2 as at 16-Mar-2021

- Extent gain on this day 55k, 13 k less than the average gain on this day (of the last 10 years) of 68k,
- Extent gain from minimum on this date is 1.66 million km2, 0.51 million km2, (44.2%) more than the 10 year average of 1.15 million km2.
- Extent is 34th lowest in the satellite record of which 19 lower values are in the years before 2000

- Extent is  474 k LESS than 2015
- Extent is  1,717 k MORE than 2017
- Extent is  1,432 k MORE than 2006
- Extent is  408 k MORE than 2020
- Extent is  587 k MORE than the 1980's Average

- On average  10.4% of ice gain from minimum to maximum done, and 188 days to maximum

Projections. (Table JAXA-Ant1)

Average remaining freeze (of the last 10 years) would produce a maximum in Sept 2020 of 19.28 million km2, 1.21 million km2 above the 2017 record low maximum of 18.06 million km2.
___________________________________________________________
Click on image  for full-size

[gerontocrat]

JAXA ANTARCTIC SEA ICE EXTENT:  4,519,783 KM2 as at 17-Mar-2021

- Extent gain on this day 72k, 0 k less than the average gain on this day (of the last 10 years) of 72k,
- Extent gain from minimum on this date is 1.73 million km2, 0.51 million km2, (41.6%) more than the 10 year average of 1.22 million km2.
- Extent is 34th lowest in the satellite record of which 19 lower values are in the years before 2000

- Extent is  517 k LESS than 2015
- Extent is  1,741 k MORE than 2017
- Extent is  1,433 k MORE than 2006
- Extent is  436 k MORE than 2020
- Extent is  594 k MORE than the 1980's Average

- On average  10.8% of ice gain from minimum to maximum done, and 187 days to maximum

Projections. (Table JAXA-Ant1)

Average remaining freeze (of the last 10 years) would produce a maximum in Sept 2020 of 19.28 million km2, 1.21 million km2 above the 2017 record low maximum of 18.06 million km2.
___________________________________________________________
Click on image  for full-size

[gerontocrat]

JAXA ANTARCTIC SEA ICE EXTENT:  4,574,009 KM2 as at 18-Mar-2021

- Extent gain on this day 54k, 32 k less than the average gain on this day (of the last 10 years) of 86k,
- Extent gain from minimum on this date is 1.79 million km2, 0.48 million km2, (36.4%) more than the 10 year average of 1.31 million km2.
- Extent is 33rd lowest in the satellite record of which 19 lower values are in the years before 2000

- Extent is  568 k LESS than 2015
- Extent is  1,714 k MORE than 2017
- Extent is  1,422 k MORE than 2006
- Extent is  420 k MORE than 2020
- Extent is  579 k MORE than the 1980's Average

- On average  11.2% of ice gain from minimum to maximum done, and 186 days to maximum

Projections. (Table JAXA-Ant1)

Average remaining freeze (of the last 10 years) would produce a maximum in Sept 2020 of 19.24 million km2, 1.18 million km2 above the 2017 record low maximum of 18.06 million km2.
_________________________________
A well below average daily extent gain on this day moves extent up from 34th to 33rd lowest in the satellite record.
___________________________________________________________
Click on image  for full-size

[gerontocrat]

JAXA ANTARCTIC SEA ICE EXTENT:  4,653,156 KM2 as at 19-Mar-2021

- Extent gain on this day 79k, 3 k less than the average gain on this day (of the last 10 years) of 82k,
- Extent gain from minimum on this date is 1.87 million km2, 0.47 million km2, (34.0%) more than the 10 year average of 1.39 million km2.
- Extent is 33th lowest in the satellite record of which 19 lower values are in the years before 2000

- Extent is  583 k LESS than 2015
- Extent is  1,719 k MORE than 2017
- Extent is  1,408 k MORE than 2006
- Extent is  425 k MORE than 2020
- Extent is  590 k MORE than the 1980's Average

- On average  11.7% of ice gain from minimum to maximum done, and 185 days to maximum

Projections. (Table JAXA-Ant1)

Average remaining freeze (of the last 10 years) would produce a maximum in Sept 2020 of 19.24 million km2, 1.18 million km2 above the 2017 record low maximum of 18.06 million km2.
___________________________________________________________
Click on image  for full-size

[gerontocrat]

JAXA ANTARCTIC SEA ICE EXTENT:  4,737,484 KM2 as at 20-Mar-2021

- Extent gain on this day 84k, 13 k more than the average gain on this day (of the last 10 years) of 71k,
- Extent gain from minimum on this date is 1.95 million km2, 0.49 million km2, (33.3%) more than the 10 year average of 1.46 million km2.
- Extent is 33th lowest in the satellite record of which 19 lower values are in the years before 2000

- Extent is  612 k LESS than 2015
- Extent is  1,757 k MORE than 2017
- Extent is  1,386 k MORE than 2006
- Extent is  416 k MORE than 2020
- Extent is  604 k MORE than the 1980's Average

- On average  12.2% of ice gain from minimum to maximum done, and 184 days to maximum

Projections. (Table JAXA-Ant1)

Average remaining freeze (of the last 10 years) would produce a maximum in Sept 2020 of 19.25 million km2, 1.19 million km2 above the 2017 record low maximum of 18.06 million km2.
___________________________________________________________
Click on image  for full-size

[gerontocrat]

JAXA ANTARCTIC SEA ICE EXTENT:  4,832,960 KM2 as at 21-Mar-2021

- Extent gain on this day 95k, 25 k more than the average gain on this day (of the last 10 years) of 70k,
- Extent gain from minimum on this date is 2.05 million km2, 0.51 million km2, (33.4%) more than the 10 year average of 1.53 million km2.
- Extent is 33th lowest in the satellite record of which 19 lower values are in the years before 2000

- Extent is  600 k LESS than 2015
- Extent is  1,814 k MORE than 2017
- Extent is  1,443 k MORE than 2006
- Extent is  422 k MORE than 2020
- Extent is  629 k MORE than the 1980's Average

- On average  12.8% of ice gain from minimum to maximum done, and 183 days to maximum

Projections. (Table JAXA-Ant1)

Average remaining freeze (of the last 10 years) would produce a maximum in Sept 2020 of 19.28 million km2, 1.22 million km2 above the 2017 record low maximum of 18.06 million km2.
___________________________________________________________
Click on image  for full-size

[gerontocrat]

JAXA ANTARCTIC SEA ICE EXTENT:  4,926,266 KM2 as at 22-Mar-2021

- Extent gain on this day 93k, 17 k more than the average gain on this day (of the last 10 years) of 76k,
- Extent gain from minimum on this date is 2.14 million km2, 0.53 million km2, (32.9%) more than the 10 year average of 1.61 million km2.
- Extent is 32nd lowest in the satellite record of which 18 lower values are in the years before 2000

- Extent is  579 k LESS than 2015
- Extent is  1,888 k MORE than 2017
- Extent is  1,471 k MORE than 2006
- Extent is  440 k MORE than 2020
- Extent is  649 k MORE than the 1980's Average

- On average  13.4% of ice gain from minimum to maximum done, and 182 days to maximum

Projections. (Table JAXA-Ant1)

Average remaining freeze (of the last 10 years) would produce a maximum in Sept 2020 of 19.30 million km2, 1.24 million km2 above the 2017 record low maximum of 18.06 million km2.
___________________________________________________________
Click on image  for full-size

[gerontocrat]

JAXA ANTARCTIC SEA ICE EXTENT:  5,005,940 KM2 as at 23-Mar-2021

- Extent gain on this day 80k, 7 k less than the average gain on this day (of the last 10 years) of 87k,
- Extent gain from minimum on this date is 2.22 million km2, 0.52 million km2, (30.8%) more than the 10 year average of 1.70 million km2.
- Extent is 32th lowest in the satellite record of which 18 lower values are in the years before 2000

- Extent is  581 k LESS than 2015
- Extent is  1,920 k MORE than 2017
- Extent is  1,438 k MORE than 2006
- Extent is  464 k MORE than 2020
- Extent is  647 k MORE than the 1980's Average

- On average  13.9% of ice gain from minimum to maximum done, and 42817 days to maximum

Projections. (Table JAXA-Ant1)

Average remaining freeze (of the last 10 years) would produce a maximum in Sept 2020 of 19.29 million km2, 1.23 million km2 above the 2017 record low maximum of 18.06 million km2.
___________________________________________________________
Click on image  for full-size

[gerontocrat]

JAXA ANTARCTIC SEA ICE EXTENT:  5,107,012 KM2 as at 24-Mar-2021

- Extent gain on this day 101k, 20 k more than the average gain on this day (of the last 10 years) of 81k,
- Extent gain from minimum on this date is 2.32 million km2, 0.54 million km2, (30.5%) more than the 10 year average of 1.78 million km2.
- Extent is 32nd lowest in the satellite record of which 18 lower values are in the years before 2000

- Extent is  554 k LESS than 2015
- Extent is  1,959 k MORE than 2017
- Extent is  1,397 k MORE than 2006
- Extent is  500 k MORE than 2020
- Extent is  663 k MORE than the 1980's Average

- On average  14.5% of ice gain from minimum to maximum done, and 182 days to maximum

Projections. (Table JAXA-Ant1)

Average remaining freeze (of the last 10 years) would produce a maximum in Sept 2020 of 19.31 million km2, 1.25 million km2 above the 2017 record low maximum of 18.06 million km2.
___________________________________________________________
Click on image  for full-size

[gerontocrat]

JAXA ANTARCTIC SEA ICE EXTENT:  5,208,413 KM2 as at 25-Mar-2021

- Extent gain on this day 101k, 13 k more than the average gain on this day (of the last 10 years) of 88k,
- Extent gain from minimum on this date is 2.42 million km2, 0.56 million km2, (29.8%) more than the 10 year average of 1.87 million km2.
- Extent is 32th lowest in the satellite record of which 18 lower values are in the years before 2000

- Extent is  530 k LESS than 2015
- Extent is  2,001 k MORE than 2017
- Extent is  1,403 k MORE than 2006
- Extent is  531 k MORE than 2020
- Extent is  676 k MORE than the 1980's Average

- On average  15.1% of ice gain from minimum to maximum done, and 181 days to maximum

Projections. (Table JAXA-Ant1)

Average remaining freeze (of the last 10 years) would produce a maximum in Sept 2020 of 19.32 million km2, 1.26 million km2 above the 2017 record low maximum of 18.06 million km2.
___________________________________________________________
Click on image  for full-size

[gerontocrat]

JAXA ANTARCTIC SEA ICE EXTENT:  5,249,419 KM2 as at 26-Mar-2021

- Extent gain on this day 41k, 45 k less than the average gain on this day (of the last 10 years) of 86k,
- Extent gain from minimum on this date is 2.46 million km2, 0.51 million km2, (26.1%) more than the 10 year average of 1.95 million km2.
- Extent is 32th lowest in the satellite record of which 18 lower values are in the years before 2000

- Extent is  604 k LESS than 2015
- Extent is  1,993 k MORE than 2017
- Extent is  1,366 k MORE than 2006
- Extent is  486 k MORE than 2020
- Extent is  625 k MORE than the 1980's Average

- On average  15.4% of ice gain from minimum to maximum done, and 180 days to maximum

Projections. (Table JAXA-Ant1)

Average remaining freeze (of the last 10 years) would produce a maximum in Sept 2020 of 19.28 million km2, 1.22 million km2 above the 2017 record low maximum of 18.06 million km2.
___________________________________________________________
Click on image  for full-size

[gerontocrat]

JAXA ANTARCTIC SEA ICE EXTENT:  5,312,450 KM2 as at 27-Mar-2021

- Extent gain on this day 63k, 34 k less than the average gain on this day (of the last 10 years) of 97k,
- Extent gain from minimum on this date is 2.52 million km2, 0.48 million km2, (23.2%) more than the 10 year average of 2.05 million km2.
- Extent is 31st lowest in the satellite record of which 16 lower values are in the years before 2000

- Extent is  644 k LESS than 2015
- Extent is  1,983 k MORE than 2017
- Extent is  1,319 k MORE than 2006
- Extent is  442 k MORE than 2020
- Extent is  612 k MORE than the 1980's Average

- On average  15.8% of ice gain from minimum to maximum done, and 179 days to maximum

Projections. (Table JAXA-Ant1)

Average remaining freeze (of the last 10 years) would produce a maximum in Sept 2020 of 19.24 million km2, 1.18 million km2 above the 2017 record low maximum of 18.06 million km2.
___________________________________________________________
Click on image  for full-size

[gerontocrat]

JAXA ANTARCTIC SEA ICE EXTENT:  5,384,828 KM2 as at 28-Mar-2021

- Extent gain on this day 72k, 11 k less than the average gain on this day (of the last 10 years) of 83k,
- Extent gain from minimum on this date is 2.60 million km2, 0.47 million km2, (21.8%) more than the 10 year average of 2.13 million km2.
- Extent is 30th lowest in the satellite record of which 16 lower values are in the years before 2000

- Extent is  681 k LESS than 2015
- Extent is  1,979 k MORE than 2017
- Extent is  1,322 k MORE than 2006
- Extent is  445 k MORE than 2020
- Extent is  612 k MORE than the 1980's Average

- On average  16.3% of ice gain from minimum to maximum done, and 178 days to maximum

Projections. (Table JAXA-Ant1)

Average remaining freeze (of the last 10 years) would produce a maximum in Sept 2020 of 19.23 million km2, 1.17 million km2 above the 2017 record low maximum of 18.06 million km2.
___________________________________________________________
Below avearge sea ice gain in the last 3 days has resulted in sea ice extent moving in the last 2 days from 32nd to 30th lowest in the satellite record.
___________________________________________________________
Click on image  for full-size

[gerontocrat]

JAXA ANTARCTIC SEA ICE EXTENT:  5,465,343 KM2 as at 29-Mar-2021

- Extent gain on this day 81k, 2 k more than the average gain on this day (of the last 10 years) of 79k,
- Extent gain from minimum on this date is 2.68 million km2, 0.47 million km2, (21.1%) more than the 10 year average of 2.21 million km2.
- Extent is 30th lowest in the satellite record of which 16 lower values are in the years before 2000

- Extent is  703 k LESS than 2015
- Extent is  2,003 k MORE than 2017
- Extent is  1,305 k MORE than 2006
- Extent is  413 k MORE than 2020
- Extent is  608 k MORE than the 1980's Average

- On average  16.8% of ice gain from minimum to maximum done, and 177 days to maximum

Projections. (Table JAXA-Ant1)

Average remaining freeze (of the last 10 years) would produce a maximum in Sept 2020 of 19.23 million km2, 1.17 million km2 above the 2017 record low maximum of 18.06 million km2.
___________________________________________________________
Click on image  for full-size

[gerontocrat]

JAXA ANTARCTIC SEA ICE EXTENT:  5,530,952 KM2 as at 30-Mar-2021

- Extent gain on this day 66k, 14 k less than the average gain on this day (of the last 10 years) of 80k,
- Extent gain from minimum on this date is 2.74 million km2, 0.45 million km2, (19.7%) more than the 10 year average of 2.29 million km2.
- Extent is 30th lowest in the satellite record of which 16 lower values are in the years before 2000

- Extent is  748 k LESS than 2015
- Extent is  1,984 k MORE than 2017
- Extent is  1,266 k MORE than 2006
- Extent is  383 k MORE than 2020
- Extent is  585 k MORE than the 1980's Average

- On average  17.2% of ice gain from minimum to maximum done, and 176 days to maximum

Projections. (Table JAXA-Ant1)

Average remaining freeze (of the last 10 years) would produce a maximum in Sept 2020 of 19.22 million km2, 1.16 million km2 above the 2017 record low maximum of 18.06 million km2.
___________________________________________________________
Click on image  for full-size

[gerontocrat]

The Bellinghausen-Amundsen Sea produces another surprise after its massive sea ice gains in the month from late Feb  -  fairly spectacular sea ice losses in late March.

Being adjacent to the most active part of Antarctica for mass change (e.g. PIG and Thwaites) might have something to do with it.

[gerontocrat]

JAXA ANTARCTIC SEA ICE EXTENT:  5,604,877 KM2 as at 31-Mar-2021

- Extent gain on this day 74k, 16 k less than the average gain on this day (of the last 10 years) of 90k,
- Extent gain from minimum on this date is 2.82 million km2, 0.44 million km2, (18.3%) more than the 10 year average of 2.38 million km2.
- Extent is 29th lowest in the satellite record of which 16 lower values are in the years before 2000

- Extent is  778 k LESS than 2015
- Extent is  1,963 k MORE than 2017
- Extent is  1,222 k MORE than 2006
- Extent is  369 k MORE than 2020
- Extent is  571 k MORE than the 1980's Average

- On average  17.6% of ice gain from minimum to maximum done, and 175 days to maximum

Projections. (Table JAXA-Ant1)

Average remaining freeze (of the last 10 years) would produce a maximum in Sept 2020 of 19.20 million km2, 1.14 million km2 above the 2017 record low maximum of 18.06 million km2.
___________________________________________________________
After about 3 weeks of very high sea ice extent gains starting in late Feb, recently gains have been at or below average. As a result extent has changed from 37th lowest, 7th highest, on 11th March to 29th lowest, 15th highest, on the 31 March.
___________________________________________________________
Click on image  for full-size

[gerontocrat]

JAXA Data

The March '21 monthly average sea ice extent (graph attached) is 4.52 million km2, 34th lowest, 10th highest in the satellite record. It is 519k km2 above March '20, and 340k km2 above the somewhat meaningless linear trend for March '21.

The sea ice 365 day trailing average of sea ice extent emphasis the lack of any real trend in Antarctic Sea ice. The current average, at 11.604 million km2 is just under 3k more than the lomg-term simple average of daily extent, and about 50k km2 more than the pretty much trend value for this date.

It is the vast increase in 365 day average sea ice extent in 2014 & 2015 followed by an equally large decrease in 2016 and 2017 that is most significant. How far the current increase will go is anybody's guess.

The plume of projections of sea ice extent from previous years' extent gains shows the range of possibilities for the 2021 maximum.

click images to enlarge

[oren]

A 10-yr average extent chart could show the difference between the Arctic and Antarctic very clearly.

[gerontocrat]

JAXA ANTARCTIC SEA ICE EXTENT:  5,697,119 KM2 as at 01-Apr-2021

- Extent gain on this day 92k, 6 k more than the average gain on this day (of the last 10 years) of 86k,
- Extent gain from minimum on this date is 2.91 million km2, 0.44 million km2, (18.0%) more than the 10 year average of 2.47 million km2.
- Extent is 29th lowest in the satellite record of which 16 lower values are in the years before 2000

- Extent is  810 k LESS than 2015
- Extent is  1,971 k MORE than 2017
- Extent is  1,219 k MORE than 2006
- Extent is  414 k MORE than 2020
- Extent is  588 k MORE than the 1980's Average

- On average  18.2% of ice gain from minimum to maximum done, and 174 days to maximum

Projections. (Table JAXA-Ant1)

Average remaining freeze (of the last 10 years) would produce a maximum in Sept 2020 of 19.21 million km2, 1.15 million km2 above the 2017 record low maximum of 18.06 million km2.
___________________________________________________________
Click on image  for full-size

[gerontocrat]

A 10-yr average extent chart could show the difference between the Arctic and Antarctic very clearly.

Will this do?

click to enlarge

[oren]

Will thisbdo? Of course. But a 10-yr average would make both lines much smoother.

[gerontocrat]

Will thisbdo? Of course. But a 10-yr average would make both lines much smoother.

I think a 10 year average is too smooth for the Antarctic where the real story is the still largely unexplained extreme extent increases and decreases in recent years, which a 10 year average would show as non-existent.

And I am too lazy - finding it difficult already to keep all the different spreadsheets in order.
But just for you I've added the Linear Trend lines, which sort of do the same thing. Note the hopeless R2 value for the Antarctic - 0.005.

[gerontocrat]

JAXA ANTARCTIC SEA ICE EXTENT:  5,802,514 KM2 as at 02-Apr-2021

- Extent gain on this day 105k, 25 k more than the average gain on this day (of the last 10 years) of 80k,
- Extent gain from minimum on this date is 3.01 million km2, 0.47 million km2, (18.4%) more than the 10 year average of 2.55 million km2.
- Extent is 29th lowest in the satellite record of which 16 lower values are in the years before 2000

- Extent is  805 k LESS than 2015
- Extent is  2,018 k MORE than 2017
- Extent is  1,230 k MORE than 2006
- Extent is  451 k MORE than 2020
- Extent is  612 k MORE than the 1980's Average

- On average  18.9% of ice gain from minimum to maximum done, and 173 days to maximum

Projections. (Table JAXA-Ant1)

Average remaining freeze (of the last 10 years) would produce a maximum in Sept 2020 of 19.24 million km2, 1.17 million km2 above the 2017 record low maximum of 18.06 million km2.
___________________________________________________________
Click on image  for full-size

[gerontocrat]

There is a gremlin in my Antarctic sea ice spreadsheet or in my head- it keeps going wrong and my fixes make things worse.

JAXA ANTARCTIC SEA ICE EXTENT:  5,921,250 KM2 as at 03-Apr-2021

- Extent gain on this day 119k, 23 k more than the average gain on this day (of the last 10 years) of 96k,
- Extent gain from minimum on this date is 3.13 million km2, 0.49 million km2, (18.5%) more than the 10 year average of 2.64 million km2.
- Extent is 31st lowest in the satellite record of which 17 lower values are in the years before 2000

- Extent is  775 k LESS than 2015
- Extent is  1,999 k MORE than 2017
- Extent is  1,217 k MORE than 2006
- Extent is  476 k MORE than 2020
- Extent is  642 k MORE than the 1980's Average

- On average  19.6% of ice gain from minimum to maximum done, and 172 days to maximum

Projections. (Table JAXA-Ant1)

Average remaining freeze (of the last 10 years) would produce a maximum in Sept 2020 of 19.26 million km2, 1.20 million km2 above the 2017 record low maximum of 18.06 million km2.
___________________________________________________________
2 days of above average century breaks sends extent from 29th to 31st lowest in the satellite record
___________________________________________________________
Click on image  for full-size