2021 Sea ice area and extent data

[Juan C. García]

[ADS NIPR VISHOP (JAXA)] Arctic Sea Ice Extent.

March 6^th, 2021:
     14,123,160 km², a drop of -12,172 km².
     2021 is now 9^th lowest on record.
     In the graph are today's 17 lowest years.
     Highlighted 2010's average, 2021 and the 5 years with daily lowest minimum:
          (2012, 2020, 2019, 2016 & 2007)
     The 2021 max until today happened March 5^th: 14,135,332 km².

Source: https://ads.nipr.ac.jp/vishop/#/extent.

[gerontocrat]

JAXA ARCTIC SEA ICE EXTENT:  14,123,160 KM2 as at 06-Mar-2021

- Extent loss on this day 12k, 22 k less than the average gain on this day (of the last 10 years) of 10k,
- Extent gain from minimum on this date is 10,568 k, which is 797 k, 8.2% more than the 10 year average of 9,772 k.

- Extent is at position #9 in the satellite record

- Extent is  223 k LESS than 2020,
- Extent is  511 k MORE than  2018,
- Extent is  245 k MORE than 2017
- Extent is  542 k LESS than 2012
- Extent is  30 k MORE than the 2010's Average
_____________________________________________
On average 99.7% of extent gains  from minimum to maximum done, and 2 days to maximum

Projections. (Table JAXA-Arc1)

Average remaining extent gain (of the last 10 years) would produce a maximum in March 2021 of 14.22 million km2, 0.33 million km2 above the March 2017 record low maximum of 13.88 million km2.
_______________________________________________________________
An extent loss instead of the average extent gain, but extent changes from 8th to 9th lowest.
_______________________________________________________________
N.B. Click on image to enlarge

[gerontocrat]

NSIDC Total AREA as at 06-Mar-2021 (5 day trailing average) 12,834,975 KM2         

Total Area           12,834,975    km2       -45,435    km2   <   2010's average. -522,640    km2   <   2020  155,656    km2   >   2017           Total Change    15    k   gain Peripheral Seas    15    k   gain Central Seas___   -0    k   loss           Peripheral Seas          Okhotsk______    17    k   gain Bering _______    6    k   gain Hudson Bay___   -4    k   loss Baffin  Bay____   -20    k   loss St Lawrence___    1    k   gain Greenland____    0    k   gain Barents ______    16    k   gain           Central Arctic  Ocean Seas          Chukchi______   -5    k   loss Beaufort_____   -2    k   loss CAA_________   -0    k   loss East Siberian__   -4    k   loss Central Arctic_    7    k   gain Laptev_______    2    k   gain Kara_________    3    k   gain

         
Sea ice area gain on this day 15 k, 5 k less than the last 10 years average gain of 20 k         
         
- Area is at position #7 in the satellite record.         
- Area is 45 k less than the 2010's average         
- Area is 156 k more than 2017         
- Area is 407 k more than 2016         
- Area is 523 k less than 2020          
- Area is 553 k less than 2012         
___________________________________________         
NSIDC Total EXTENT as at 06-Mar-2021 (5 day trailing average) 14,561,842 KM2         
         
NSIDC Sea ice EXTENT gain on this day 16 k, 14 k more than the 2010's average gain of 2k         
         
- EXTENT is at position #9 in the satellite record.         
- EXTENT is 90 k more than the 2010's average         
- EXTENT is 303 k more than 2017         
- EXTENT is 362 k more than 2016         
- EXTENT is 311 k less than 2020          
- EXTENT is 478 k less than 2012         
___________________________________________         
Note: Click an image for full-size         

[gerontocrat]

And for a change NSIDC area data in my JAXA analysis format

NSIDC ARCTIC SEA ICE AREA:  12,834,975 KM2 as at 06-Mar-2021

- Area gain on this day 15k, 9 k less than the average gain on this day (of the last 10 years) of 24k,
- Area gain from minimum on this date is 10,203 k, 366 k, 3.7% more than the 10 year average of 9,837 k.
- Area is at position #7 in the satellite record

- Area is  -36 k LESS than 2010's Average
- Area is  -523 k LESS than 2020
- Area is  407 k MORE than 2016
- Area is  -553 k LESS than 2012
______________________________
On average 98.4% of Area gain from minimum to maximum done, and 3 days to maximum

Projections.
Average remaining area gain (of the last 10 years) would produce a maximum in March of 13.00 million km2, 0.30 million km2 above the 2017 minimum maximum  sea ice area of 12.70 million km2.
________________________________________________________

[gerontocrat]

And a bit more on NSIDC Area

The February monthly average graph is attached. At 12.65 million km2, the Feb 21 average area is nearly 200k less than Feb 20, but 135k (equates to more than 3 years) above the linear trend value. The Feb 21 average is 9th lowest in the satellite record

Being below 2020 means that the 365 day trailing average area is in decline. At 8.38 million km2 (on 6th march) it is still 179k above the record low in Feb 2017. Only if the melt season this year is very strong, at least matching the melt in 2020, will this trailing avereg continue to decline. An average melt would see this trailing average reverse, i.e. start to gain, later this month - see graph.

As usual, click images to enlarge.

[Juan C. García]

[ADS NIPR VISHOP (JAXA)] Arctic Sea Ice Extent.

March 7^th, 2021:
     14,159,590 km², an increase of 36,430 km².
     2021 is 9^th lowest on record.
     In the graph are today's 18 lowest years.
     Highlighted 2010's average, 2021 and the 5 years with daily lowest minimum:
          (2012, 2020, 2019, 2016 & 2007)
     This is a new 2021 max.

Source: https://ads.nipr.ac.jp/vishop/#/extent.

[gerontocrat]

JAXA ARCTIC SEA ICE EXTENT:  14,159,590 KM2 as at 07-Mar-2021

- Extent gain on this day 36k, 27 k more than the average gain on this day (of the last 10 years) of 9k,
- Extent gain from minimum on this date is 10,605 k, which is 825 k, 8.4% more than the 10 year average of 9,780 k.

- Extent is at position #9 in the satellite record

- Extent is  131 k LESS than 2020,
- Extent is  550 k MORE than  2018,
- Extent is  293 k MORE than 2017
- Extent is  549 k LESS than 2012
- Extent is  51 k MORE than the 2010's Average
_____________________________________________
On average 99.8% of extent gains  from minimum to maximum done, and 1 days to maximum

Projections. (Table JAXA-Arc1)

Average remaining extent gain (of the last 10 years) would produce a maximum in March 2021 of 14.25 million km2, 0.36 million km2 above the March 2017 record low maximum of 13.88 million km2.
_______________________________________________________________
N.B. Click on image to enlarge

[gerontocrat]

NSIDC Total AREA as at 07-Mar-2021 (5 day trailing average) 12,847,792 KM2         

Total Area           12,847,792    km2       -48,672    km2   <   2010's average. -514,477    km2   <   2020  152,718    km2   >   2017           Total Change    13    k   gain Peripheral Seas    10    k   gain Central Seas___    3    k   gain           Peripheral Seas          Okhotsk______    8    k   gain Bering _______    6    k   gain Hudson Bay___   -7    k   loss Baffin  Bay____   -15    k   loss St Lawrence___   -3    k   loss Greenland____    0    k   gain Barents ______    20    k   gain           Central Arctic  Ocean Seas          Chukchi______   -4    k   loss Beaufort_____   -2    k   loss CAA_________    0    k   gain East Siberian__   -3    k   loss Central Arctic_    5    k   gain Laptev_______   -0    k   loss Kara_________    7    k   gain

         
Sea ice area gain on this day 13 k, 0 k less than the last 10 years average gain of 13 k         
         
- Area is at position #8 in the satellite record.         
- Area is 49 k less than the 2010's average         
- Area is 153 k more than 2017         
- Area is 409 k more than 2016         
- Area is 514 k less than 2020          
- Area is 547 k less than 2012         
___________________________________________         
NSIDC Total EXTENT as at 07-Mar-2021 (5 day trailing average) 14,557,326 KM2         
         
NSIDC Sea ice EXTENT loss on this day 5 k, 6 k less than the 2010's average gain of 1k         
         
- EXTENT is at position #9 in the satellite record.         
- EXTENT is 81 k more than the 2010's average         
- EXTENT is 303 k more than 2017         
- EXTENT is 364 k more than 2016         
- EXTENT is 306 k less than 2020          
- EXTENT is 473 k less than 2012         
___________________________________________         
Note: Click an image for full-size         

[Juan C. García]

[ADS NIPR VISHOP (JAXA)] Arctic Sea Ice Extent.

March 8^th, 2021:
     14,163,510 km², an increase of 3,920 km².
     2021 is 10^th lowest on record.
     In the graph are today's 15 lowest years.
     Highlighted 2010's average, 2021 and the 5 years with daily lowest minimum:
          (2012, 2020, 2019, 2016 & 2007)
     This is a new 2021 max.

Source: https://ads.nipr.ac.jp/vishop/#/extent.

[gerontocrat]

JAXA ARCTIC SEA ICE EXTENT:  14,163,510 KM2 as at 08-Mar-2021

- Extent gain on this day 4k, 14 k more than the average LOSS on this day (of the last 10 years) of 10k,
- Extent gain from minimum on this date is 10,609 k, which is 839 k, 8.6% more than the 10 year average of 9,770 k.

- Extent is at position #10 in the satellite record

- Extent is  118 k LESS than 2020,
- Extent is  535 k MORE than  2018,
- Extent is  345 k MORE than 2017
- Extent is  443 k LESS than 2012
- Extent is  63 k MORE than the 2010's Average
_____________________________________________
On average 99.7% of extent gains  from minimum to maximum done, and 0 days to maximum

Projections. (Table JAXA-Arc1)

Average remaining extent gain (of the last 10 years) would produce a maximum in March 2021 of 14.25 million km2, 0.36 million km2 above the March 2017 record low maximum of 13.88 million km2.
_______________________________________________________________
N.B. Click on image to enlarge

[gerontocrat]

NSIDC Total AREA as at 08-Mar-2021 (5 day trailing average) 12,855,850 KM2         

Total Area           12,855,850    km2       -46,765    km2   <   2010's average. -493,997    km2   <   2020  176,075    km2   >   2017           Total Change    8    k   gain Peripheral Seas    9    k   gain Central Seas___   -1    k   loss           Peripheral Seas          Okhotsk______    6    k   gain Bering _______   -7    k   loss Hudson Bay___   -3    k   loss Baffin  Bay____   -9    k   loss St Lawrence___   -0    k   loss Greenland____    3    k   gain Barents ______    20    k   gain           Central Arctic  Ocean Seas          Chukchi______   -6    k   loss Beaufort_____   -2    k   loss CAA_________    0    k   gain East Siberian__   -3    k   loss Central Arctic_    2    k   gain Laptev_______   -2    k   loss Kara_________    10    k   gain

         
Sea ice area gain on this day 8 k, 2 k more than the last 10 years average gain of 6 k         
         
- Area is at position #8 in the satellite record.         
- Area is 47 k less than the 2010's average         
- Area is 176 k more than 2017         
- Area is 409 k more than 2016         
- Area is 494 k less than 2020          
- Area is 531 k less than 2012         
___________________________________________         
NSIDC Total EXTENT as at 08-Mar-2021 (5 day trailing average) 14,553,986 KM2         
         
NSIDC Sea ice EXTENT loss on this day 3 k, 1 k less than the 2010's average loss of 4k         
         
- EXTENT is at position #9 in the satellite record.         
- EXTENT is 77 k more than the 2010's average         
- EXTENT is 312 k more than 2017         
- EXTENT is 354 k more than 2016         
- EXTENT is 277 k less than 2020          
- EXTENT is 462 k less than 2012
_____________________________________________
This is the  time of year when extent and area values are in a dither, and a lot of people on this forum get in a dither about calling for the melting thread to open.
___________________________________________         
Note: Click an image for full-size         

[Juan C. García]

[ADS NIPR VISHOP (JAXA)] Arctic Sea Ice Extent.

March 9^th, 2021:
     14,204,377 km², an increase of  40,867 km².    (Up we go!)
     2021 is 10^th lowest on record.
     In the graph are today's 15 lowest years.
     Highlighted 2010's average, 2021 and the 5 years with daily lowest minimum:
          (2012, 2020, 2019, 2016 & 2007)
     This is a new 2021 max.

Source: https://ads.nipr.ac.jp/vishop/#/extent.

[gerontocrat]

JAXA ARCTIC SEA ICE EXTENT:  14,204,377 KM2 as at 09-Mar-2021

- Extent gain on this day 41k, 58 k more than the average loss on this day (of the last 10 years) of 17k,
- Extent gain from minimum on this date is 10,650 k, which is 897 k, 9.2% more than the 10 year average of 9,753 k.

- Extent is at position #10 in the satellite record

- Extent is  92 k LESS than 2020,
- Extent is  544 k MORE than  2018,
- Extent is  434 k MORE than 2017
- Extent is  313 k LESS than 2012
- Extent is  126 k MORE than the 2010's Average
_____________________________________________
On average 99.6% of extent gains  from minimum to maximum done, and -1 days to maximum

Projections. (Table JAXA-Arc1)

Average remaining extent gain (of the last 10 years) would produce a maximum in March 2021 of 14.30 million km2, 0.40 million km2 above the March 2017 record low maximum of 13.88 million km2.
_______________________________________________________________
N.B. Click on image to enlarge

[gerontocrat]

NSIDC Total AREA as at 09-Mar-2021 (5 day trailing average) 12,865,169 KM2         

Total Area           12,865,169    km2       -41,895    km2   <   2010's average. -456,259    km2   <   2020  207,970    km2   >   2017           Total Change    9    k   gain Peripheral Seas    14    k   gain Central Seas___   -4    k   loss           Peripheral Seas          Okhotsk______    7    k   gain Bering _______   -11    k   loss Hudson Bay___   -2    k   loss Baffin  Bay____   -3    k   loss St Lawrence___   -2    k   loss Greenland____    4    k   gain Barents ______    20    k   gain           Central Arctic  Ocean Seas          Chukchi______   -5    k   loss Beaufort_____   -3    k   loss CAA_________    0    k   gain East Siberian__   -3    k   loss Central Arctic_   -0    k   loss Laptev_______   -3    k   loss Kara_________    10    k   gain

         
Sea ice area gain on this day 9 k, 4 k more than the last 10 years average gain of 5 k         
         
- Area is at position #7 in the satellite record.         
- Area is 42 k less than the 2010's average         
- Area is 208 k more than 2017         
- Area is 393 k more than 2016         
- Area is 456 k less than 2020          
- Area is 504 k less than 2012         
___________________________________________         
NSIDC Total EXTENT as at 09-Mar-2021 (5 day trailing average) 14,536,781 KM2         
         
NSIDC Sea ice EXTENT loss on this day 17 k, 15 k more than the 2010's average loss of 2k         
         
- EXTENT is at position #8 in the satellite record.         
- EXTENT is 61 k more than the 2010's average         
- EXTENT is 318 k more than 2017         
- EXTENT is 316 k more than 2016         
- EXTENT is 269 k less than 2020          
- EXTENT is 447 k less than 2012         
___________________________________________         
Note: Click an image for full-size         

[Juan C. García]

[ADS NIPR VISHOP (JAXA)] Arctic Sea Ice Extent.

March 10^th, 2021:
     14,237,433 km², an increase of 33,056 km².
     2021 is 10^th lowest on record.
     In the graph are today's 15 lowest years.
     Highlighted 2010's average, 2021 and the 5 years with daily lowest minimum:
          (2012, 2020, 2019, 2016 & 2007)
     This is a new 2021 max.

Source: https://ads.nipr.ac.jp/vishop/#/extent.

[gerontocrat]

JAXA ARCTIC SEA ICE EXTENT:  14,237,433 KM2 as at 10-Mar-2021

- Extent gain on this day 33k, 29 k more than the average gain on this day (of the last 10 years) of 4k,
- Extent gain from minimum on this date is 10,683 k, which is 926 k, 9.5% more than the 10 year average of 9,757 k.

- Extent is at position #10 in the satellite record

- Extent is  55 k LESS than 2020,
- Extent is  497 k MORE than  2018,
- Extent is  495 k MORE than 2017
- Extent is  273 k LESS than 2012
- Extent is  157 k MORE than the 2010's Average
_____________________________________________
Projections. (Table JAXA-Arc1)

Average remaining extent gain (of the last 10 years) would produce a maximum in March 2021 of 14.32 million km2, 0.42 million km2 above the March 2017 record low maximum of 13.88 million km2.
_______________________________________________________________
N.B. Click on image to enlarge

[gerontocrat]

NSIDC Total AREA as at 10-Mar-2021 (5 day trailing average) 12,884,884 KM2         

Total Area           12,884,884    km2       -25,024    km2   <   2010's average. -420,888    km2   <   2020  244,354    km2   >   2017           Total Change    20    k   gain Peripheral Seas    22    k   gain Central Seas___   -2    k   loss           Peripheral Seas          Okhotsk______    2    k   gain Bering _______   -8    k   loss Hudson Bay___    1    k   gain Baffin  Bay____    5    k   gain St Lawrence___   -1    k   loss Greenland____    7    k   gain Barents ______    16    k   gain           Central Arctic  Ocean Seas          Chukchi______    2    k   gain Beaufort_____   -0    k   loss CAA_________    0    k   gain East Siberian__   -3    k   loss Central Arctic_   -4    k   loss Laptev_______   -4    k   loss Kara_________    7    k   gain

         
Sea ice area gain on this day 20 k, 15 k more than the last 10 years average gain of 5 k         
         
- Area is at position #7 in the satellite record.         
- Area is 25 k less than the 2010's average         
- Area is 244 k more than 2017         
- Area is 387 k more than 2016         
- Area is 421 k less than 2020          
- Area is 465 k less than 2012         
___________________________________________         
NSIDC Total EXTENT as at 10-Mar-2021 (5 day trailing average) 14,540,270 KM2         
         
NSIDC Sea ice EXTENT gain on this day 3 k, 5 k more than the 2010's average loss of 2k         
         
- EXTENT is at position #8 in the satellite record.         
- EXTENT is 69 k more than the 2010's average         
- EXTENT is 340 k more than 2017         
- EXTENT is 320 k more than 2016         
- EXTENT is 262 k less than 2020          
- EXTENT is 425 k less than 2012
_____________________________________________
Hanging around waiting for the melting season to start is.....Boring!         
___________________________________________         
Note: Click an image for full-size         

[gerontocrat]

The St Lawrence Sea freezing season didn't really take off this year,( and too late for anything more than a brief hiccup?).

[LDorey]

_____________________________________________
Hanging around waiting for the melting season to start is.....Boring!         

No kidding, the maximum just doesn't have the same cachet as the minimum...oh well it's coming... In the meantime may I say thank you again for all the awesome data

[Juan C. García]

[ADS NIPR VISHOP (JAXA)] Arctic Sea Ice Extent.

March 11^th, 2021:
     14,219,764 km², a drop of -17,669 km².
     2021 is now 9^th lowest on record.
     In the graph are today's 15 lowest years.
     Highlighted 2010's average, 2021 and the 5 years with daily lowest minimum:
          (2012, 2020, 2019, 2016 & 2007)
     2021 max (until today): March 10^th: 14,237,433 km².

Source: https://ads.nipr.ac.jp/vishop/#/extent.

[gerontocrat]

JAXA ARCTIC SEA ICE EXTENT:  14,219,764 KM2 as at 11-Mar-2021

- Extent loss on this day 18k, 46 k less than the average gain on this day (of the last 10 years) of 28k,
- Extent gain from minimum on this date is 10,665 k, which is 880 k, 9.0% more than the 10 year average of 9,785 k.

- Extent is at position #9 in the satellite record

- Extent is  67 k LESS than 2020,
- Extent is  440 k MORE than  2018,
- Extent is  438 k MORE than 2017
- Extent is  354 k LESS than 2012
- Extent is  110 k MORE than the 2010's Average
_____________________________________________
On average 100.0% of extent gains  from minimum to maximum done, and -3 days to maximum

Projections. (Table JAXA-Arc1)

Average remaining extent gain (of the last 10 years) would produce a maximum in March 2021 of 14.28 million km2, 0.39 million km2 above the March 2017 record low maximum of 13.88 million km2.
_______________________________________________________________
Just maybe on the 10th March was the maximum extent.
_______________________________________________________________
N.B. Click on image to enlarge

[gerontocrat]

NSIDC Total AREA as at 11-Mar-2021 (5 day trailing average) 12,911,736 KM2         

Total Area           12,911,736    km2       -3,906    km2   <   2010's average. -378,848    km2   <   2020  295,125    km2   >   2017           Total Change    27    k   gain Peripheral Seas    31    k   gain Central Seas___   -4    k   loss           Peripheral Seas          Okhotsk______    8    k   gain Bering _______   -7    k   loss Hudson Bay___    5    k   gain Baffin  Bay____    10    k   gain St Lawrence___   -0    k   loss Greenland____    5    k   gain Barents ______    11    k   gain           Central Arctic  Ocean Seas          Chukchi______    4    k   gain Beaufort_____    1    k   gain CAA_________    1    k   gain East Siberian__   -3    k   loss Central Arctic_   -3    k   loss Laptev_______   -5    k   loss Kara_________    1    k   gain

         
Sea ice area gain on this day 27 k, 20 k more than the last 10 years average gain of 7 k         
         
- Area is at position #7 in the satellite record.         
- Area is 4 k less than the 2010's average         
- Area is 295 k more than 2017         
- Area is 391 k more than 2016         
- Area is 379 k less than 2020          
- Area is 421 k less than 2012         
___________________________________________         
NSIDC Total EXTENT as at 11-Mar-2021 (5 day trailing average) 14,563,995 KM2         
         
NSIDC Sea ice EXTENT gain on this day 24 k, 15 k more than the 2010's average gain of 9k         
         
- EXTENT is at position #8 in the satellite record.         
- EXTENT is 88 k more than the 2010's average         
- EXTENT is 364 k more than 2017         
- EXTENT is 335 k more than 2016         
- EXTENT is 255 k less than 2020          
- EXTENT is 393 k less than 2012   
______________________________________
No sign of a maximum yet - rather the reverse as daily extent and area gains are increasing.      
___________________________________________         
Note: Click an image for full-size         

[Juan C. García]

[ADS NIPR VISHOP (JAXA)] Arctic Sea Ice Extent.

March 12^th, 2021:
     14,145,795 km², a drop of -73,969 km².
     2021 is now 9 8^th lowest on record.
     In the graph are today's 15 lowest years.
     Highlighted 2010's average, 2021 and the 5 years with daily lowest minimum:
          (2012, 2020, 2019, 2016 & 2007)
     2021 max (until today): March 10^th: 14,237,433 km² (total drop: -91,638 km²).

Source: https://ads.nipr.ac.jp/vishop/#/extent.

Can you correct (edit) this error in your post...

Thank you.

[VeliAlbertKallio]

Can you correct (edit) this error in your post (then delete this note here)

Looking at your table, it should read like this:

March 12th, 2021:
     14,145,795 km2, a drop of -73,969 km2.
     2021 is now 8th lowest on record.

You seem to have misread line somehow.

[ADS NIPR VISHOP (JAXA)] Arctic Sea Ice Extent.

March 12^th, 2021:
     14,145,795 km², a drop of -73,969 km².
     2021 is now 9^th lowest on record.
     In the graph are today's 15 lowest years.
     Highlighted 2010's average, 2021 and the 5 years with daily lowest minimum:
          (2012, 2020, 2019, 2016 & 2007)
     2021 max (until today): March 10^th: 14,237,433 km² (total drop: -91,638 km²).

Source: https://ads.nipr.ac.jp/vishop/#/extent.

[gerontocrat]

JAXA ARCTIC SEA ICE EXTENT:  14,145,795 KM2 as at 12-Mar-2021

- Extent loss on this day 74k, 99 k less than the average gain on this day (of the last 10 years) of 25k,
- Extent gain from minimum on this date is 10,591 k, which is 781 k, 8.0% more than the 10 year average of 9,810 k.

- Extent is at position #8 in the satellite record

- Extent is  121 k LESS than 2020,
- Extent is  339 k MORE than  2018,
- Extent is  299 k MORE than 2017
- Extent is  426 k LESS than 2012
- Extent is  12 k MORE than the 2010's Average
_____________________________________________
On average 100% of extent gains  from minimum to maximum done, and -4 days to maximum

Projections. (Table JAXA-Arc1)

Average remaining extent gain (of the last 10 years) would produce a maximum in March 2021 of 14.24 million km2, 0.35 million km2 above the March 2017 record low maximum of 13.88 million km2.
_______________________________________________________________
8 out of the last 10 years say the maximum was reached on the 10th March at 14.24 million km2. One more day to clinch it?
_______________________________________________________________
N.B. Click on image to enlarge

[gerontocrat]

NSIDC Total AREA as at 12-Mar-2021 (5 day trailing average) 12,935,883 KM2         

Total Area           12,935,883    km2        7,861    km2   >   2010's average. -319,745    km2   <   2020  340,370    km2   >   2017           Total Change    24    k   gain Peripheral Seas    26    k   gain Central Seas___   -1    k   loss           Peripheral Seas          Okhotsk______    3    k   gain Bering _______   -3    k   loss Hudson Bay___    8    k   gain Baffin  Bay____    14    k   gain St Lawrence___    1    k   gain Greenland____   -2    k   loss Barents ______    4    k   gain           Central Arctic  Ocean Seas          Chukchi______    3    k   gain Beaufort_____    1    k   gain CAA_________    0    k   gain East Siberian__   -3    k   loss Central Arctic_    1    k   gain Laptev_______   -4    k   loss Kara_________    1    k   gain

         
Sea ice area gain on this day 24 k, 14 k more than the last 10 years average gain of 10 k         
         
- Area is at position #7 in the satellite record.         
- Area is 8 k more than the 2010's average         
- Area is 340 k more than 2017         
- Area is 398 k more than 2016         
- Area is 320 k less than 2020          
- Area is 383 k less than 2012         
___________________________________________         
NSIDC Total EXTENT as at 12-Mar-2021 (5 day trailing average) 14,572,051 KM2         
         
NSIDC Sea ice EXTENT gain on this day 8 k, 7 k less than the last 10 years average gain of 15k         
         
- EXTENT is at position #8 in the satellite record.         
- EXTENT is 83 k more than the 2010's average         
- EXTENT is 362 k more than 2017         
- EXTENT is 339 k more than 2016         
- EXTENT is 259 k less than 2020          
- EXTENT is 397 k less than 2012   
_______________________________________
On 11th March NSIDC one-day extent was at the current record maximum of  14.866 million km2 and dropped by 100k on the 12th March.   
100k is a very big daily change at this time of year when extent is dithering at around the maximum - ice mobility?
___________________________________________         
Note: Click an image for full-size         

[Juan C. García]

[ADS NIPR VISHOP (JAXA)] Arctic Sea Ice Extent.

March 13^th, 2021:
     14,075,320 km², a drop of -70,475 km².
     2021 is now 7^th lowest on record.
     In the graph are today's 16 lowest years on the range 2000-2021 (excludes 1995).
     Highlighted 2010's average, 2021 and the 5 years with daily lowest minimum:
          (2012, 2020, 2019, 2016 & 2007)
     2021 max (until today): March 10^th: 14,237,433 km² (total drop: -162,113 km²).

Source: https://ads.nipr.ac.jp/vishop/#/extent.

[gerontocrat]

JAXA ARCTIC SEA ICE EXTENT:  14,075,320 KM2 as at 13-Mar-2021

- Extent loss on this day 70k, 72 k less than the average gain on this day (of the last 10 years) of 2k,

- Extent is at position #7 in the satellite record

- Extent is  204 k LESS than 2020,
- Extent is  237 k MORE than  2018,
- Extent is  260 k MORE than 2017
- Extent is  503 k LESS than 2012
- Extent is  60 k LESS than the 2010's Average
_____________________________________________
Projections. (Table JAXA-Arc1)

14 out of the last 15 years say the maximum was reached on the 10th March at 14.24 million km2. (see 1st image attached).
Significant daily extent losses have seen extent move up from 10th to 7th lowest in the satellite record in the last 3 days.

Can Oren resist declaring Open Sesame! to the 2021 melting Season?
_______________________________________________________________
N.B. Click on image to enlarge

[gerontocrat]

NSIDC Total AREA as at 13-Mar-2021 (5 day trailing average) 12,933,116 KM2         

Total Area           12,933,116    km2       -17,148    km2   <   2010's average. -255,804    km2   <   2020  344,648    km2   >   2017           Total Change   -3    k   loss Peripheral Seas    2    k   gain Central Seas___   -5    k   loss           Peripheral Seas          Okhotsk______   -4    k   loss Bering _______   -6    k   loss Hudson Bay___    7    k   gain Baffin  Bay____    11    k   gain St Lawrence___   -2    k   loss Greenland____   -2    k   loss Barents ______   -2    k   loss           Central Arctic  Ocean Seas          Chukchi______    2    k   gain Beaufort_____    1    k   gain CAA_________   -0    k   loss East Siberian__   -3    k   loss Central Arctic_    4    k   gain Laptev_______   -4    k   loss Kara_________   -4    k   loss

         
Sea ice area loss on this day 3 k, 17 k less than the last 10 years average gain of 14 k         
         
- Area is at position #8 in the satellite record.         
- Area is 17 k less than the 2010's average         
- Area is 345 k more than 2017         
- Area is 379 k more than 2016         
- Area is 256 k less than 2020          
- Area is 356 k less than 2012         
___________________________________________         
NSIDC Total EXTENT as at 13-Mar-2021 (5 day trailing average) 14,557,452 KM2         
         
NSIDC Sea ice EXTENT loss on this day 15 k, 31 k less than the 2010's average gain of 16k         
         
- EXTENT is at position #7 in the satellite record.         
- EXTENT is 52 k more than the 2010's average         
- EXTENT is 340 k more than 2017         
- EXTENT is 318 k more than 2016         
- EXTENT is 281 k less than 2020          
- EXTENT is 398 k less than 2012   
_____________________________________
On 11th March NSIDC one-day extent was at the current record maximum of  14.866 million km2 and dropped by 106k on the 12th March and another 136k on the 13th March.   
242k in 2 days is an enormous daily change at this time of year when extent is dithering at around the maximum - ice mobility?   

Can Oren still resist the demand to open the 2021 melting season. I hope yes then I can tease him some more   
___________________________________________         
Note: Click an image for full-size         

[Juan C. García]

[ADS NIPR VISHOP (JAXA)] Arctic Sea Ice Extent.

March 14^th, 2021:
     14,025,551 km², a drop of -49,769 km².
     2021 is 7^th lowest on record.
     In the graph are today's 16 lowest years on the range 2000-2021 (excludes 1995).
     Highlighted 2010's average, 2021 and the 5 years with daily lowest minimum:
          (2012, 2020, 2019, 2016 & 2007)
     2021 max (until today): March 10^th: 14,237,433 km² (total drop: -211,882 km²).

Source: https://ads.nipr.ac.jp/vishop/#/extent.

[gerontocrat]

I attach a couple of tables on the assumption that the 2021 JAXA extent maximum was reached on the 10th March @ 14.237 million km2.

This maximum is 8th lowest in the satellite record, 210k less than the max of 2020, and 359k more than the record low max of 13.878 million km2 in 2017.

click to enlarge image

[gerontocrat]

my first post of the melting season 2021

JAXA ARCTIC SEA ICE EXTENT:  14,025,551 KM2 as at 14-Mar-2021

- Extent loss on this day 50k, 56 k less than the average gain on this day (of the last 10 years) of 6k,
- Extent loss from maximum on this date is 212 k, which is 102 k, 93% more than the 10 year average of 110 k.

- Extent is at position #7 in the satellite record

- Extent is  256 k LESS than 2020,
- Extent is  172 k MORE than  2018,
- Extent is  190 k MORE than 2017
- Extent is  546 k LESS than 2012
- Extent is  114 k LESS than the 2010's Average
_____________________________________________
On average 1.1% of extent losses  from maximum to minimum done, and 184 days to minimum

Projections. (Table JAXA-Arc1)

Average remaining extent loss (of the last 10 years) would produce a minimum in September 2021 of 4.10 million km2, 0.92 million km2 above the Sept 2012 record low maximum of 3.18 million km2.
_______________________________________________________________
N.B. Click on image to enlarge

[gerontocrat]

NSIDC Total AREA as at 14-Mar-2021 (5 day trailing average) 12,917,470 KM2         

Total Area           12,917,470    km2       -53,302    km2   <   2010's average. -197,363    km2   <   2020  314,790    km2   >   2017           Total Change   -16    k   loss Peripheral Seas   -12    k   loss Central Seas___   -4    k   loss           Peripheral Seas          Okhotsk______   -3    k   loss Bering _______   -9    k   loss Hudson Bay___    2    k   gain Baffin  Bay____    6    k   gain St Lawrence___   -3    k   loss Greenland____   -3    k   loss Barents ______   -2    k   loss           Central Arctic  Ocean Seas          Chukchi______   -1    k   loss Beaufort_____    2    k   gain CAA_________   -1    k   loss East Siberian__    0    k   gain Central Arctic_    5    k   gain Laptev_______   -4    k   loss Kara_________   -5    k   loss

         
Sea ice area loss on this day 16 k, 26 k less than the last 10 years average gain of 10 k         
         
- Area is at position #7 in the satellite record.         
- Area is 53 k less than the 2010's average         
- Area is 315 k more than 2017         
- Area is 394 k more than 2016         
- Area is 197 k less than 2020          
- Area is 340 k less than 2012         
___________________________________________         
NSIDC Total EXTENT as at 14-Mar-2021 (5 day trailing average) 14,536,972 KM2         
         
NSIDC Sea ice EXTENT loss on this day 20 k, 31 k less than the 2010's average gain of 11k         
         
- EXTENT is at position #7 in the satellite record.         
- EXTENT is 18 k more than the 2010's average         
- EXTENT is 300 k more than 2017         
- EXTENT is 313 k more than 2016         
- EXTENT is 286 k less than 2020          
- EXTENT is 410 k less than 2012         
___________________________________________         
Note: Click an image for full-size         

[gerontocrat]

Blurb for freezing season
NSIDC ARCTIC SEA ICE AREA:  12,917,470 KM2 as at 14-Mar-2021

- Area loss on this day 16k, 37 k less than the average gain on this day (of the last 10 years) of 21k,
- Area gain from minimum on this date is 10,286 k, 379 k, 3.8% more than the 10 year average of 9,906 k.
- Area is at position #7 in the satellite record

- Area is  -44 k LESS than 2010's Average
- Area is  -197 k LESS than 2020
- Area is  394 k MORE than 2016
- Area is  -340 k LESS than 2012
______________________________
5 days after average date of maximum

Projections.
Was the maximum of the 5-day area measurement on the 12th March @ 12.936 million km2?
Daily area on this day is 12.806 million km2, some 111k less than the 5 day measure so the answer is most likely yes.

But average remaining area gain (of the last 10 years) would produce a maximum in March of 12.96 million km2, 0.26 million km2 above the 2017 minimum maximum  sea ice area of 12.70 million km2.
________________________________________________________
click to enlarge images

[gerontocrat]

I think this will be the last posting of NSIDC 5-day extent that assumes the freezing season still lives, as 1-day extent data says extent dropped by 270k in the last 3 days.

NSIDC ARCTIC SEA ICE EXTENT:  14,536,972 KM2 as at 14-Mar-2021

- Extent loss on this day 20k, 31 k less than the average gain on this day (of the last 10 years) of 11k,
- Extent gain from minimum on this date is 10,800 k, which is 729 k, 7.2% more than the 10 year average of 10,071 k.

- Extent is at position #7 in the satellite record

- Extent is  286 k LESS than 2020,
- Extent is  379 k MORE than  2018,
- Extent is  300 k MORE than 2017
- Extent is  410 k LESS than 2012
- Extent is  18 k MORE than the 2010's Average
_____________________________________________
On average 100.0% of extent gains  from minimum to maximum done, and -6 days to maximum

Projections.

Average remaining extent gain (of the last 10 years) would produce a maximum in March 2021 of 14.63 million km2, 0.39 million km2 above the March 2018 record low maximum of 14.24 million km2.
_______________________________________________________________
N.B. Click on image to enlarge

[Juan C. García]

[ADS NIPR VISHOP (JAXA)] Arctic Sea Ice Extent.

March 15^th, 2021:
     14,030,884 km², a small increase of 5,333 km².
     2021 is 7^th lowest on record.
     In the graph are today's 19 lowest years on range 2000-2021 (excludes 1995 & 1996).
     Highlighted 2010's average, 2021 and the 5 years with daily lowest minimum:
          (2012, 2020, 2019, 2016 & 2007)
     2021 max (until today): March 10^th: 14,237,433 km² (total drop: -206,549 km²).

Source: https://ads.nipr.ac.jp/vishop/#/extent.

[gerontocrat]

1st post that assumes we are in the 2021 melting season...

JAXA ARCTIC SEA ICE EXTENT:  14,030,884 KM2 as at 15-Mar-2021

- Extent gain on this day 5k, 16 k less than the average gain on this day (of the last 10 years) of 21k,
- Extent loss from maximum on this date is 207 k, which is 118 k, 134% more than the 10 year average of 88 k.

- Extent is at position #7 in the satellite record

- Extent is  254 k LESS than 2020,
- Extent is  118 k LESS than  2019,
- Extent is  156 k MORE than 2016
- Extent is  635 k LESS than 2012
- Extent is  127 k LESS than the 2010's Average
_____________________________________________
On average 0.9% of extent losses  from maximum to minimum done, and 183 days to minimum

Projections. (Table JAXA-Arc1)

Average remaining extent loss (of the last 10 years) would produce a minimum in September 2021 of 4.09 million km2, 0.91 million km2 above the Sept 2012 record low maximum of 3.18 million km2.
_______________________________________________________________
N.B. Click on image to enlarge

[gerontocrat]

NSIDC Total AREA as at 15-Mar-2021 (5 day trailing average) 12,905,678 KM2         

Total Area           12,905,678    km2       -78,909    km2   <   2010's average. -134,713    km2   <   2020  297,613    km2   >   2017           Total Change   -12    k   loss Peripheral Seas   -15    k   loss Central Seas___    3    k   gain           Peripheral Seas          Okhotsk______   -7    k   loss Bering _______   -14    k   loss Hudson Bay___    3    k   gain Baffin  Bay____    5    k   gain St Lawrence___   -3    k   loss Greenland____   -1    k   loss Barents ______    3    k   gain           Central Arctic  Ocean Seas          Chukchi______   -4    k   loss Beaufort_____   -1    k   loss CAA_________   -2    k   loss East Siberian__    4    k   gain Central Arctic_    9    k   gain Laptev_______   -1    k   loss Kara_________   -2    k   loss

         
Sea ice area loss on this day 12 k, 18 k less than the last 10 years average gain of 6 k         
         
- Area is at position #7 in the satellite record.         
- Area is 79 k less than the 2010's average         
- Area is 298 k more than 2017         
- Area is 412 k more than 2016         
- Area is 135 k less than 2020          
- Area is 353 k less than 2012         
___________________________________________         
NSIDC Total EXTENT as at 15-Mar-2021 (5 day trailing average) 14,513,117 KM2         
         
NSIDC Sea ice EXTENT loss on this day 24 k, 41 k less than the 2010's average gain of 17k         
         
- EXTENT is at position #7 in the satellite record.         
- EXTENT is 25 k less than the 2010's average         
- EXTENT is 255 k more than 2017         
- EXTENT is 269 k more than 2016         
- EXTENT is 296 k less than 2020          
- EXTENT is 454 k less than 2012         
___________________________________________         
Note: Click an image for full-size         

[jdallen]

I attach a couple of tables on the assumption that the 2021 JAXA extent maximum was reached on the 10th March @ 14.237 million km2.

This maximum is 8th lowest in the satellite record, 210k less than the max of 2020, and 359k more than the record low max of 13.878 million km2 in 2017.

I think it's worth noting here, that even at a difference of 358k, the 2021 max is just 2 1/2 percent  higher than 2017.  In short, the difference in negligible.

[gerontocrat]

JAXA Extent Data - Current estimate of March monthly average.

I attach the March monthly average graph based on actual exten change to 15th March and average extent gains from then to end-March.  The estimate of March 2021 average is 13.99 million km2, 9th lowest in the satellite record, 117k below March 2020, and 166k above the linear trend value for March '21.

Still a lot depending on melt from now to March 31.

[Juan C. García]

[ADS NIPR VISHOP (JAXA)] Arctic Sea Ice Extent.

March 16^th, 2021:
     14,086,582 km², an increase of 55,698 km².
     2021 is 7^th lowest on record.
     In the graph are today's 19 lowest years on range 2000-2021 (excludes 1995 & 1996).
     Highlighted 2010's average, 2021 and the 5 years with daily lowest minimum:
          (2012, 2020, 2019, 2016 & 2007)
     2021 max (until today): March 10^th: 14,237,433 km² (total drop: -150,851 km²).

Source: https://ads.nipr.ac.jp/vishop/#/extent.

[gerontocrat]

JAXA ARCTIC SEA ICE EXTENT:  14,086,582 KM2 as at 16-Mar-2021

- Extent gain on this day 56k, 60 k more than the average loss on this day (of the last 10 years) of 4k,
- Extent gain from minimum on this date is 10,532 k, which is 698 k, 7.1% more than the 10 year average of 9,834 k.

- Extent is at position #7 in the satellite record

- Extent is  184 k LESS than 2020,
- Extent is  212 k MORE than  2018,
- Extent is  381 k MORE than 2017
- Extent is  607 k LESS than 2012
- Extent is  71 k LESS than the 2010's Average
_____________________________________________
On average 101.0% of extent gains  from minimum to maximum done, and -8 days to maximum

Projections. (Table JAXA-Arc1)

Average remaining extent gain (of the last 10 years) would produce a maximum in March 2021 of 14.24 million km2, 0.35 million km2 above the March 2017 record low maximum of 13.88 million km2.
_______________________________________________________________
See what happens when the melting season is announced ? - Sea ice extent goes up.
_______________________________________________________________
N.B. Click on image to enlarge

[gerontocrat]

NSIDC Total AREA as at 16-Mar-2021 (5 day trailing average) 12,895,362 KM2         

Total Area           12,895,362    km2       -92,589    km2   <   2010's average. -93,257    km2   <   2020  291,578    km2   >   2017           Total Change   -10    k   loss Peripheral Seas   -19    k   loss Central Seas___    9    k   gain           Peripheral Seas          Okhotsk______   -16    k   loss Bering _______   -14    k   loss Hudson Bay___    1    k   gain Baffin  Bay____    2    k   gain St Lawrence___   -3    k   loss Greenland____    1    k   gain Barents ______    9    k   gain           Central Arctic  Ocean Seas          Chukchi______   -3    k   loss Beaufort_____   -2    k   loss CAA_________   -1    k   loss East Siberian__    4    k   gain Central Arctic_    8    k   gain Laptev_______    2    k   gain Kara_________    2    k   gain

         
Sea ice area loss on this day 10 k, 9 k more than the last 10 years average loss of 1 k         
         
- Area is at position #7 in the satellite record.         
- Area is 93 k less than the 2010's average         
- Area is 292 k more than 2017         
- Area is 431 k more than 2016         
- Area is 93 k less than 2020          
- Area is 385 k less than 2012         
___________________________________________         
NSIDC Total EXTENT as at 16-Mar-2021 (5 day trailing average) 14,497,670 KM2         
         
NSIDC Sea ice EXTENT loss on this day 15 k, 23 k less than the 2010's average gain of 8k         
         
- EXTENT is at position #8 in the satellite record.         
- EXTENT is 49 k less than the 2010's average         
- EXTENT is 267 k more than 2017         
- EXTENT is 237 k more than 2016         
- EXTENT is 314 k less than 2020          
- EXTENT is 496 k less than 2012         
___________________________________________         
Note: Click an image for full-size         

[Juan C. García]

[ADS NIPR VISHOP (JAXA)] Arctic Sea Ice Extent.

March 17^th, 2021:
     14,124,156 km², an increase of 37,574 km².
     2021 is now 10^th lowest on record.
     In the graph are today's 19 lowest years on range 2000-2021 (excludes 1995 & 1996).
     Highlighted 2010's average, 2021 and the 5 years with daily lowest minimum:
          (2012, 2020, 2019, 2016 & 2007)
     2021 max (until today): March 10^th: 14,237,433 km² (total drop: -113,277 km²).

Source: https://ads.nipr.ac.jp/vishop/#/extent.

[gerontocrat]

JAXA ARCTIC SEA ICE EXTENT:  14,124,156 KM2 as at 17-Mar-2021

- Extent gain on this day 38k, 60 k more than the average loss on this day (of the last 10 years) of 22k,
- Extent gain from minimum on this date is 10,569 k, which is 757 k, 7.7% more than the 10 year average of 9,812 k.

- Extent is at position #10 in the satellite record

- Extent is  151 k LESS than 2020,
- Extent is  233 k MORE than  2018,
- Extent is  517 k MORE than 2017
- Extent is  557 k LESS than 2012
- Extent is  10 k LESS than the 2010's Average
_____________________________________________
On average 101.2% of extent gains  from minimum to maximum done, and -9 days to maximum

Projections. (Table JAXA-Arc1)

Average remaining extent gain (of the last 10 years) would produce a maximum in March 2021 of 14.24 million km2, 0.35 million km2 above the March 2017 record low maximum of 13.88 million km2.
_______________________________________________________________
Extent still heads in the wrong direction for the melting season . Extent increases, and falls from 7th lowest to 10th lowest in the satellite record.
_______________________________________________________________
N.B. Click on image to enlarge

[gerontocrat]

NSIDC Total AREA as at 17-Mar-2021 (5 day trailing average) 12,887,483 KM2         

Total Area           12,887,483    km2       -90,146    km2   <   2010's average. -79,885    km2   <   2020  302,835    km2   >   2017           Total Change   -8    k   loss Peripheral Seas   -18    k   loss Central Seas___    10    k   gain           Peripheral Seas          Okhotsk______   -20    k   loss Bering _______   -10    k   loss Hudson Bay___   -2    k   loss Baffin  Bay____    3    k   gain St Lawrence___   -3    k   loss Greenland____    7    k   gain Barents ______    7    k   gain           Central Arctic  Ocean Seas          Chukchi______   -2    k   loss Beaufort_____   -2    k   loss CAA_________   -1    k   loss East Siberian__    4    k   gain Central Arctic_    6    k   gain Laptev_______    3    k   gain Kara_________    2    k   gain

         
Sea ice area loss on this day 8 k, 3 k less than the last 10 years average loss of 11 k         
         
- Area is at position #7 in the satellite record.         
- Area is 90 k less than the 2010's average         
- Area is 303 k more than 2017         
- Area is 453 k more than 2016         
- Area is 80 k less than 2020          
- Area is 414 k less than 2012         
___________________________________________         
NSIDC Total EXTENT as at 17-Mar-2021 (5 day trailing average) 14,499,211 KM2         
         
NSIDC Sea ice EXTENT gain on this day 2 k, 3 k more than the 2010's average loss of 1k         
         
- EXTENT is at position #8 in the satellite record.         
- EXTENT is 49 k less than the 2010's average         
- EXTENT is 312 k more than 2017         
- EXTENT is 228 k more than 2016         
- EXTENT is 302 k less than 2020          
- EXTENT is 515 k less than 2012         
___________________________________________         
Note: Click an image for full-size         

[Juan C. García]

[ADS NIPR VISHOP (JAXA)] Arctic Sea Ice Extent.

March 18^th, 2021:
     14,144,629 km², an increase of 20,473 km².
     2021 is 10^th lowest on record.
     In the graph are today's 19 lowest years on range 2000-2021 (excludes 1995 & 1996).
     Highlighted 2010's average, 2021 and the 5 years with daily lowest minimum:
          (2012, 2020, 2019, 2016 & 2007)
     2021 max (until today): March 10^th: 14,237,433 km² (total drop: -92,804 km²).

Source: https://ads.nipr.ac.jp/vishop/#/extent.

[gerontocrat]

JAXA ARCTIC SEA ICE EXTENT:  14,144,629 KM2 as at 18-Mar-2021

- Extent gain on this day 20k, 44 k less than the average loss on this day (of the last 10 years) of 24k,
- Extent loss from maximum on this date is 93 k, which is 45 k, 33% less than the 10 year average of 138 k.

- Extent is at position #10 in the satellite record

- Extent is  65 k LESS than 2020,
- Extent is  139 k MORE than  2019,
- Extent is  242 k MORE than 2016
- Extent is  535 k LESS than 2012
- Extent is  26 k MORE than the 2010's Average
_____________________________________________
On average 1.4% of extent losses  from maximum to minimum done, and 180 days to minimum

Projections. (Table JAXA-Arc1)

Average remaining extent loss (of the last 10 years) would produce a minimum in September 2021 of 4.25 million km2, 1.07 million km2 above the Sept 2012 record low maximum of 3.18 million km2.
_______________________________________________________________
N.B. Click on image to enlarge

[Phil.]

JAXA ARCTIC SEA ICE EXTENT:  14,144,629 KM2 as at 18-Mar-2021

- Extent gain on this day 20k, 44 k less than the average loss on this day (of the last 10 years) of 24k,

'greater than'?

[gerontocrat]

JAXA ARCTIC SEA ICE EXTENT:  14,144,629 KM2 as at 18-Mar-2021

- Extent gain on this day 20k, 44 k less than the average loss on this day (of the last 10 years) of 24k,

'greater than'?

Depends on your point of view. From the point of view of the melting season losses are expected. So a gain is a negative loss, i.e. less than the the average loss of...

Sometimes I compromise (cop out) and write - different from.

This happens every year close to maximum, and minimum, when daily change is contrarily up and down. Someone should tell the Arctic sea ice to behave properly.