2019 sea ice area and extent data

[Juan C. García]

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

August 15^th, 2019:
     4,734,585 km², a drop of -33,967 km².
     2019 is 2^nd lowest on record.
     (2012 highlighted).

[Ktb]

Semimonthly BOE evaluation

August 15th extent was 4,734,585 km^2. With on average just 29 days to go until the end of the melt season on September 13th, we now require a daily drop of -128,779 km^2 for a BOE to occur. (See Attachment 1).

Total extent loss thus far in August 2019 was -1,221,266 km^2. And total extent loss so far this season is -9,536,536 km^2. This has resulted in the current average daily drop of -61,132 km^2. If the month of August ended today, this would be the 2nd fastest rate of melt for the same period for the years 2007-2019. (See Attachment 2). 
Additionally, if the melt season ended today, -61,132 km^2 would place 2019 as 1st out of 13 for the years 2007-2019.

Looking only at the month of August thus far, we have averaged -81,418 km^2 per day. If the month of August ended today, this average daily drop places August 2019 as 2nd out of 13 (2007-2019) in average daily August melt. (See Attachment 3).

[gerontocrat]

JAXA ARCTIC SEA ICE EXTENT :- 4,734,585 km2（August 15, 2019）

JAXA daily extent loss on this day was greatly below average.

- Extent is 2nd lowest in the satellite record (49 days at lowest this year),
- Extent is 185 k greater than 2012, 548 k less than 2016.
- Extent loss on this day 34 k, 29 k less than the average loss on this day of 63 k.
- Extent loss from maximum 9.537 k, 713 k (8.1%) greater than the average of 8,823k loss from maximum by this day,
- On average 89.3% of the melting season done, with 29 days to average date of minimum (13 September).
- if extent loss ceased today 2019 would be the 10th lowest minimum in the satellite record.

The Perils of Projections.
Average remaining melt (1.06 million km) would give a minimum of 3.68 million km2, 2nd lowest in the satellite record, 0.50 million km2 above the 2012 low of 3.18 million km2 and 0.34 million below the 2nd lowest in 2016 of 4.02 million km2.

Ice Melt Outlook The peak days of daily melt are past. From now to minimum, on average daily extent loss will gradually but erratically reduce until the minimum. 

JAXA Extent loss low, NSIDC Ara loss very high. The impact of the weather on these measures seems to be somewhat unpredictable - reflecting the fragility and broken up nature of the remaining ice?
____________________________________________________________

[pauldry600]

Dispersion may make below 4m unachievable

[gerontocrat]

NSIDC Total Area as at 15 August 2019 (5 day trailing average) 3,235,701 km2

On this day area loss above average

Total Area           3,235,701    km2       -579,532    km2   <   2010's average. -482,518    km2   <   2018 -1,337,551    km2   <   2000's average.           Total Area Change   -59    k   loss Peripheral Seas   -0    k   loss Central Seas__   -58    k   loss Other Seas___   -0    k   loss           Peripheral Seas          Bering _______    0    k   gain Baffin  Bay____   -2    k   loss Greenland____    2    k   gain Barents ______   -1    k   loss           CAB Seas          Beaufort_____   -6    k   loss CAA_________   -4    k   loss East Siberian__   -3    k   loss Central Arctic_   -34    k   loss           Kara_________   -3    k   loss Laptev_______   -6    k   loss Chukchi______   -3    k   loss           Other Seas          Okhotsk______    0    k   gain St Lawrence___    -    k   loss Hudson Bay___   -0    k   loss

- Area loss 59 k, 33 k MORE than the 2010's average area loss of 26 k on this day,
- Total area 2nd Lowest, 286 k LESS than 2016, and 192 k MORE than 2012.

On this day area loss greater than 2012 and equal to 2016
while NSIDC daily extent lost 49k.
________________________________________________________________________
Outlook
We are now well into the period of reducing and very variable daily area loss that that will slide to zero by mid-September.

End of season wobbles makes comments out-of-date almost before they are typed. Just sit back and watch.

[gerontocrat]

The Central Arctic Sea has at last got below the 2010's average.
The next 4 weeks or so - I wonder how much area it will lose.

[Alphabet Hotel]

NSIDC daily extent

[Stephan]

The distance 2019 ↔ 2012 is slowly increasing.

[philopek]

The distance 2019 ↔ 2012 is slowly increasing.

After one day of real difference ?

Look at winds patterns and it's obviously what happens, huge dispersion on several fronts and where compaction would happen there is nothing left to compact or the reminder is already quite compact.

A few days of opening gap can easily be compensated with a few days of bigger drops given the right conditions and this has nothing to do with mid or long term outcome.

Lets' wait let's says 4-5 days. Once the gap will be higher than 300'000 km2 one can slowly consider that the race may be over but not yet.

[gerontocrat]

JAXA ARCTIC SEA ICE EXTENT :- 4,695,733 km2（August 16, 2019）

JAXA daily extent loss on this day was again greatly below average.

- Extent is 2nd lowest in the satellite record (49 days at lowest this year),
- Extent is 229 k greater than 2012, 478 k less than 2016.
- Extent loss on this day 39 k, 29 k less than the average loss on this day of 68 k.
- Extent loss from maximum 9.575 k, 684 k (7.7%) greater than the average of 8,891k loss from maximum by this day,
- On average 90.0% of the melting season done, with 28 days to average date of minimum (13 September).
- if extent loss ceased today 2019 would be the 10th lowest minimum in the satellite record.

The Perils of Projections.
Average remaining melt (0.99 million km) would give a minimum of 3.71 million km2, 2nd lowest in the satellite record, 0.53 million km2 above the 2012 low of 3.18 million km2 and 0.31 million below the 2nd lowest in 2016 of 4.02 million km2.

Ice Melt Outlook The peak days of daily melt are past. From now to minimum, on average daily extent loss will gradually but erratically reduce until the minimum. 

JAXA Extent loss low, NSIDC Area loss high. The impact of the weather on these different measures seems to be somewhat unpredictable - reflecting the fragility and broken up nature of the remaining ice?
____________________________________________________________

[Juan C. García]

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

August 16^th, 2019:
     4,695,733 km², a drop of -38,852 km².
     2019 is 2^nd lowest on record.
     (2012 highlighted).

[Tom_Mazanec]

Is there anything about 2019 that is exceptional? If I understand, 2012 was exceptional because of a big cyclone in the Arctic (am I right)? Is 2019 just a near "normal" year?

[sailor]

Is there anything about 2019 that is exceptional? If I understand, 2012 was exceptional because of a big cyclone in the Arctic (am I right)? Is 2019 just a near "normal" year?

It is (almost?) record warm May-June-July in the Arctic, and August is not cold. It is exceptional now but is following the expected trend.

[FishOutofWater]

The Arctic oscillation, associated with subsidence over the Arctic, has been exceptional as has the albedo warming potential.

Arctic waters have taken up stunning amounts of heat.

The GAC took heat from mid-ocean waters to melt Arctic ice. This melting season insolation and advected heat from the south has added heat to Arctic waters. So, what's exceptional about this melting season is the amount of heat added to the Arctic climate system of ocean, atmosphere and ice. There's only a very small chance that sea ice extent and area will end up lower this year than 2012, but there is little solace from that when considering long-term Arctic warming.

[gerontocrat]

NSIDC Total Area as at 16 August 2019 (5 day trailing average) 3,178,642 km2

On this day area loss again above average

Total Area           3,178,642    km2       -604,927    km2   <   2010's average. -525,683    km2   <   2018 -1,356,006    km2   <   2000's average.           Total Area Change   -57    k   loss Peripheral Seas    1    k   gain Central Seas__   -58    k   loss Other Seas___   -0    k   loss           Peripheral Seas          Bering _______    0    k   gain Baffin  Bay____   -0    k   loss Greenland____    2    k   gain Barents ______   -1    k   loss           CAB Seas          Beaufort_____   -4    k   loss CAA_________   -5    k   loss East Siberian__   -3    k   loss Central Arctic_   -38    k   loss           Kara_________   -2    k   loss Laptev_______   -4    k   loss Chukchi______   -2    k   loss           Other Seas          Okhotsk______    0    k   gain St Lawrence___    -    k   loss Hudson Bay___   -1    k   loss

- Area loss 57 k, 26 k MORE than the 2010's average area loss of 31 k on this day,
- Total area 2nd Lowest, 260 k LESS than 2016, and 168 k MORE than 2012.

On this day area loss greater than 2012 and less than 2016
while NSIDC daily extent lost a mere 21k.
________________________________________________________________________
Outlook
We are now well into the period of reducing and very variable daily area loss that that will slide to zero by mid-September.

It was 2016, not 2012, that led the final area loss charge of the season

End of season wobbles makes comments out-of-date almost before they are typed. Just sit back and watch.

[Glen Koehler]

Is there anything about 2019 that is exceptional? If I understand, 2012 was exceptional because of a big cyclone in the Arctic (am I right)? Is 2019 just a near "normal" year?

     Seems to me that 2019 stands out for the overall poor quality of the ice (thickness, concentration).  Extent and Area do not necessarily reflect that poor condition  so even though it seems unlikely that 2019 will set new low Extent record, it represents another step down the path of arctic Sea Ice degradation, and all that that implies for the climate system as a whole. 

    One aspect the current situation that stands out to me is that the largest chuck of highest concentration CAB ice is on the Atlantic edge.  Very doubtful it will happen in the dwindling melt season, but a cyclone to export that chunk out of the CAB would make a big dent in the Extent/Area/Volume stats.  Though it probably won't happen, just the fact that it could is ominous.  And that IMO is the ASI headline for 2019 -- the ice is in worse shape and more vulnerable than ever. 
 
   As somebody commented above, this degraded state is occurring at/near minimum of a weak solar cycle.  Our friendly star is remarkably stable but the slight variation in energy received from the sun across solar cycle can nudge annual average global surface temperature up and down by ca. 0.1C.  So with ASI in this shape in 2019, what happens at peak of next cycle (albeit also expected to be relatively weak amplitude cycle relative to past 100 years)?  And of course with GHG emissions roaring along, and 93% of the extra retained energy going into the ocean waters, add that to next solar peak in 5-6 years and 2012's freak low Extent/Volume could start to look like the good old days when there were still millions of km2 MYI sea ice that carried over between years.

   So I guess the 2019 headline could be the beginning of the end for the ASI functioning over the last 12,000 years as a climatic anchor and stabilizer during the Holocene period.  That's the period during which so-called  "wise apes", aka Homo sapiens, learned how to do things like agriculture, science, literature and all the rest.  All just my lurker opinion of course.

     Climate sanity should be a requirement for any policy and politician to even be considered.  As the World Bank put it in back in 2012 (before the last 7 years of sooner/more severe climate study results) - the continuity of an "organized global community" depends on it.  I confess that I find it numerically fascinating to learn about the complex interactions of the ASI as it falls apart.  So a preliminary thanks to Neven, gerontocrat and others for hosting this soiree again this year.  But I don't want to see what "disorganized" global community looks like.  It would be nice if there was no reason to enjoy this forum.     

[Shared Humanity]

Is there anything about 2019 that is exceptional? If I understand, 2012 was exceptional because of a big cyclone in the Arctic (am I right)? Is 2019 just a near "normal" year?

What, if anything, is no longer exceptional about the arctic? 2019 is going to finish 2nd lowest.

[gerontocrat]

Bits & Pieces

If area loss stopped on this day, 2019 area would be 9th lowest in the satellite record.

The sea ice area of Hudson Bay has been lowest in the satellite record since 27 July (apart from one day 12 Aug). This is despite the cold area in the south of the bay.

The Kara Sea never completely melts out. Maybe this year it will give it a try.

The Central Arctic Sea ice area maybe starting a significant charge downwards. How low can it go?

[gerontocrat]

NSIDC Have done a mid-month analysis up to Aug 1 - http://nsidc.org/arcticseaicenews/

They are plumping for second lowest - using 12 previous years remaining ice loss.

That was my methodology that belonged to me! Gerontocrat claimed to his lawyer (who said - too bad, suck it up!).

[philopek]

The distance 2019 ↔ 2012 is slowly increasing.

After one day of real difference ?

Lets' wait let's says 4-5 days. Once the gap will be higher than 300'000 km2 one can slowly consider that the race may be over but not yet.

Second out of 4-5 days   220k - 225k above 2012 while area losses are in overdrive exactly as per the theory, that dispersion means extent growth or loss slowdown at a higher melt rate leading to lower area

2-3 more days at this rate and we can start to focus on other point of interest, still interesting times given the current weather conditions.

I would not be surprised when the large area of mostly uniform first year ice would reach zero in  quantity soon.

Somehow i wonder how it's possible that there is still first year ice left under this year's circumstances.

Looking at sat images i suspect a mix of "traveled" thick ice with first year ice and that the widely spread thicker floes help keep the water cooler a bit longer then pure first year ice  could.

[Alphabet Hotel]

NSIDC daily extent

[Juan C. García]

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

August 17^th, 2019:
     4,634,809 km², a drop of -60,924 km².
     2019 is 2^nd lowest on record.
     (2012 highlighted).

[Juan C. García]

If the ASI melting would stop today, 2019 would be the 10^th lowest of record.
I expect that by Aug 20^th or 21^st, 2019 can be the 6^th lowest on record.

September's mínimum (ADS-NIPR-VISHOP-JAXA), from lowest to highest:

[gerontocrat]

JAXA ARCTIC SEA ICE EXTENT :- 4,634,809 km2（August 17, 2019）

JAXA daily extent loss on this day went up to above average.

- Extent is 2nd lowest in the satellite record (49 days at lowest this year),
- Extent is 258 k greater than 2012, 466 k less than 2016.
- Extent loss on this day 61 k, 9 k more than the average loss on this day of 52 k.
- Extent loss from maximum 9,636 k, 693 k (7.7%) greater than the average of 8,944k loss from maximum by this day,
- On average 90.5% of the melting season done, with 27 days to average date of minimum (13 September).
- if extent loss ceased today 2019 would be the 10th lowest minimum in the satellite record.

The Perils of Projections.
Average remaining melt (0.99 million km) would give a minimum of 3.70 million km2, 2nd lowest in the satellite record, 0.52 million km2 above the 2012 low of 3.18 million km2 and 0.32 million below the 2nd lowest in 2016 of 4.02 million km2.

Ice Melt Outlook The peak days of daily melt are past. From now to minimum, on average daily extent loss will gradually but erratically reduce until the minimum. 
____________________________________________________________

[gerontocrat]

NSIDC Total Area as at 17 August 2019 (5 day trailing average) 3,122,044  km2

On this day area loss again above average

Total Area           3,122,044    km2       -620,106    km2   <   2010's average. -547,409    km2   <   2018 -1,376,244    km2   <   2000's average.           Total Area Change   -57    k   loss Peripheral Seas   -3    k   loss Central Seas__   -54    k   loss Other Seas___    0    k   gain           Peripheral Seas          Bering _______   -0    k   loss Baffin  Bay____    1    k   gain Greenland____   -2    k   loss Barents ______   -1    k   loss           CAB Seas          Beaufort_____    0    k   gain CAA_________   -5    k   loss East Siberian__   -6    k   loss Central Arctic_   -37    k   loss           Kara_________    1    k   gain Laptev_______   -6    k   loss Chukchi______   -1    k   loss           Other Seas          Okhotsk______    0    k   gain St Lawrence___    -    k   loss Hudson Bay___    0    k   gain

- Area loss 57 k, 25 k MORE than the 2010's average area loss of 32 k on this day,
- Total area 2nd Lowest, 242 k LESS than 2016, and 156 k MORE than 2012.

On this day area loss again was greater than 2012 and less than 2016
while NSIDC daily extent lost slightly up at 33 k.
________________________________________________________________________
Outlook
We are now well into the period of reducing and very variable daily area loss that that will slide to zero by mid-September.

End of season wobbles makes comments out-of-date almost before they are typed. Just sit back and watch.

[Steven]

NSIDC daily area is now 3.076 million km2, which is second lowest for the date:



The year-to-date minimum for 2019 so far is 7th lowest on record.  It will probably go below the 2010, 2017, 2007 and 2011 minima soon.

     year    minimum
1   2012   2.228 million km2
2   2016   2.463
3   2011   2.916
4   2007   2.955
5   2017   3.001
6   2010   3.072
7   2019  3.076 (year-to-date)
8   2008   3.080
9   2015   3.139
10 2018   3.235

[gerontocrat]

Central Arctic Sea continues the downward dash

Compaction/concentration reduces and dispersion increases as area tends to reduce faster than extent at the moment

[Alphabet Hotel]

NSIDC daily extent

[Juan C. García]

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

August 18^th, 2019:
     4,563,912 km², a drop of -70,897 km².
     2019 is 2^nd lowest on record.
     (2012 highlighted).

[marcel_g]

...

Arctic waters have taken up stunning amounts of heat.

...
 There's only a very small chance that sea ice extent and area will end up lower this year than 2012, but there is little solace from that when considering long-term Arctic warming.

So what you're saying is, even if this year doesn't break records, subsequent years will show the effects of all that heat build up in the system? If it is, then I'd agree. I'm guessing it'll show up initially as delayed freezing and lower winter maximums.

I've been wondering how the ice has managed to survive given the heat build up in 2016-2018, but considering what you're saying, I'd think that in any year past this one the ice will be lucky to survive.

[gerontocrat]

JAXA ARCTIC SEA ICE EXTENT :- 4,563,912 km2（August 18, 2019）

JAXA daily extent loss on this day went up to well above average.

- Extent is 2nd lowest in the satellite record (49 days at lowest this year),
- Extent is 258 k greater than 2012, 452 k less than 2016.
- Extent loss on this day 71 k, 18 k more than the average loss on this day of 53 k.
- Extent loss from maximum 9,707 k, 711 k (7.9%) greater than the average of 8,996 k loss from maximum by this day,
- Extent loss from maximum to date is also second highest in at least the last 12 years, only second to 2012,
- On average 91.1% of the melting season done, with 26 days to average date of minimum (13 September).

The Perils of Projections.
Average remaining melt (0.99 million km) would give a minimum of 3.68 million km2, 2nd lowest in the satellite record, 0.50 million km2 above the 2012 low of 3.18 million km2 and 0.34 million below the 2nd lowest in 2016 of 4.02 million km2.

Ice Melt Outlook The peak days of daily melt are past. From now to minimum, on average daily extent loss will gradually but erratically reduce until the minimum. 
____________________________________________________________
Due to events my postings may also be erratic as to timing.

[gerontocrat]

JAXA ARCTIC SEA ICE EXTENT :- 4,563,912 km2（August 18, 2019）
OTHER STUFF

Minimum Projections - Graph attached
As the number of days remaining to minimum diminish, the range of projections from previous years also diminishes, now to between 3.4 and 4 million.

If Extent loss stopped on this day 2109 would be the 9th lowest minimum in the satellite record. Table attached.

The 365 day trailing average (Graph attached) of sea ice extent continues to fall quickly - and could be at a record low by early 2020 or even very late 2019. Much depends on a fast or slow refreeze.

[RealityCheck]

Hi Gerontocrat
Re your 365 chart: what if you fit a straight line to the 3 peaks and also to the troughs? This would show a 'channel' that might indicate future trends...?
And many thanks for the ongoing updates of data... they are a daily go-to for me...
Cheers!

[gerontocrat]

Hi Gerontocrat
Re your 365 chart: what if you fit a straight line to the 3 peaks and also to the troughs? This would show a 'channel' that might indicate future trends...?
And many thanks for the ongoing updates of data... they are a daily go-to for me...
Cheers!

I am looking at other sea ice stuff - e.g. ice-free days & open water trends - so yes I could, but I won't, at least for some time.

ps: Looks like NSIDC is having a day off

[gerontocrat]

NSIDC late in putting up the data today

NSIDC Total Area as at 17 August 2019 (5 day trailing average) 3,086,627  km2

On this day area loss back to below average

Total Area           3,086,627    km2       -603,515    km2   <   2010's average. -525,240    km2   <   2018 -1,382,921    km2   <   2000's average.           Total Area Change   -35    k   loss Peripheral Seas   -3    k   loss Central Seas__   -33    k   loss Other Seas___    1    k   gain           Peripheral Seas          Bering _______    0    k   gain Baffin  Bay____    0    k   gain Greenland____   -2    k   loss Barents ______   -1    k   loss           CAB Seas          Beaufort_____   -1    k   loss CAA_________   -1    k   loss East Siberian__   -8    k   loss Central Arctic_   -18    k   loss           Kara_________    0    k   gain Laptev_______   -6    k   loss Chukchi______   -0    k   loss           Other Seas          Okhotsk______   -0    k   loss St Lawrence___    -    k   loss Hudson Bay___    1    k   gain

- Area loss 35 k, 6 k less than the 2010's average area loss of 41 k on this day,
- Total area 2nd Lowest, 196 k LESS than 2016, and 156 k MORE than 2012.

On this day area loss equal to 2012 and less than 2016
while NSIDC daily extent loss well up at 79 k.
________________________________________________________________________
Outlook
We are now well into the period of reducing and very variable daily area loss that that will slide to zero by mid-September.

End of season wobbles makes comments out-of-date almost before they are typed. Just sit back and watch.

[RealityCheck]

Hi Gerontocrat
Re your 365 chart: what if you fit a straight line to the 3 peaks and also to the troughs? This would show a 'channel' that might indicate future trends...?
And many thanks for the ongoing updates of data... they are a daily go-to for me...
Cheers!

I am looking at other sea ice stuff - e.g. ice-free days & open water trends - so yes I could, but I won't, at least for some time.

Fair enough...

[Alphabet Hotel]

NSIDC daily extent

[cesium62]

Our friendly star is remarkably stable but the slight variation in energy received from the sun across solar cycle can nudge annual average global surface temperature up and down by ca. 0.1C. 

Link to a peer reviewed paper, please.  I ran the regression between solar cycle and september minimum extent.  There is no correlation.

[oren]

To avoid derailment please respond re solar cycle in this thread:
https://forum.arctic-sea-ice.net/index.php/topic,2250.msg141701.html#msg141701

[Juan C. García]

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

August 19^th, 2019:
     4,534,816 km², a drop of -29,096 km².
     2019 is 2^nd lowest on record.
     (2012 highlighted).

[Killian]

Interesting. New record virtually certain to not happen, but new 2nd lowest looking increasingly in doubt.

JAXA ASIE now needs:

 > -50k km ² to set a new low (on the same date) as 2012.

 > -25.5k km² to set the record for new 2nd lowest (on the same date) as 2016.

Even the '16 average melt is pretty high, however, '16 had it's low on the 9th/10th, so there's a fair amount of potential time for '19 to fall. '12 reached it's low on the 15th/16th, so an extension past that date is less likely.

We shall see....

[gerontocrat]

JAXA ARCTIC SEA ICE EXTENT :- 4,534,816 km2（August 19, 2019）

JAXA daily extent loss on this day went down to well below average.

- Extent is 2nd lowest in the satellite record (49 days at lowest this year),
- Extent is 309 k greater than 2012, 436 k less than 2016.
- Extent loss on this day 29 k, 23 k less than the average loss on this day of 52 k.
- Extent loss from maximum 9,736 k, 688 k (7.6%) greater than the average of 9,046 k loss from maximum by this day,
- Extent loss from maximum to date is also second highest in at least the last 12 years, only second to 2012,
- On average 91.6% of the melting season done, with 25 days to average date of minimum (13 September).

The Perils of Projections.
Average remaining melt (0.99 million km) would give a minimum of 3.70 million km2, 2nd lowest in the satellite record, 0.52 million km2 above the 2012 low of 3.18 million km2 and 0.32 million below the 2nd lowest in 2016 of 4.02 million km2.

Ice Melt Outlook The peak days of daily melt are past. From now to minimum, on average daily extent loss will gradually but erratically reduce until the minimum. 
____________________________________________________________
Due to events my postings will also be erratic as to timing.

[gerontocrat]

NSIDC Total Area as at 19 August 2019 (5 day trailing average) 3,074,980 km2

On this day area loss extremely below average

Total Area           3,074,980    km2       -564,990    km2   <   2010's average. -470,383    km2   <   2018 -1,364,272    km2   <   2000's average.           Total Area Change   -12    k   loss Peripheral Seas   -2    k   loss Central Seas__   -11    k   loss Other Seas___    1    k   gain           Peripheral Seas          Bering _______    0    k   gain Baffin  Bay____   -0    k   loss Greenland____   -1    k   loss Barents ______   -1    k   loss           CAB Seas          Beaufort_____   -4    k   loss CAA_________    0    k   gain East Siberian__   -9    k   loss Central Arctic_    5    k   gain           Kara_________    1    k   gain Laptev_______   -4    k   loss Chukchi______   -0    k   loss           Other Seas          Okhotsk______    0    k   gain St Lawrence___    -    k   loss Hudson Bay___    1    k   gain

- Area loss 12 k, 40 k less than the 2010's average area loss of 52 k on this day,
- Total area 2nd Lowest, 140 k LESS than 2016, and 190 k MORE than 2012.

On this day area loss much less than 2012 and 2016
while NSIDC daily extent loss also very low at 26 k.
________________________________________________________________________
Outlook
We are now well into the period of reducing and very variable daily area loss that that will slide to zero by mid-September.

End of season wobbles makes comments out-of-date almost before they are typed. Just sit back and watch.

[Alphabet Hotel]

NSIDC daily extent

[Juan C. García]

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

August 20^th, 2019:
     4,507,767 km², a drop of -27,049 km².
     2019 is 2^nd lowest on record.
     (2012 highlighted).

[gerontocrat]

JAXA ARCTIC SEA ICE EXTENT :- 4,507,767 km2（August 20, 2019）

JAXA daily extent loss on this day stayed down at well below average.

- Extent is 2nd lowest in the satellite record (49 days at lowest this year),
- Extent is 364 k greater than 2012, 415 k less than 2016.
- Extent loss on this day 27 k, 25 k less than the average loss on this day of 52 k.
- Extent loss from maximum 9,763 k, 663 k (7.3%) greater than the average of 9,100 k loss from maximum by this day,
- Extent loss from maximum to date is also second highest in at least the last 12 years, only second to 2012,
- On average 92.1% of the melting season done, with 24 days to average date of minimum (13 September).

The Perils of Projections.
Average remaining melt (0.78 million km) would give a minimum of 3.73 million km2, 2nd lowest in the satellite record, 0.55 million km2 above the 2012 low of 3.18 million km2 and 0.29 million below the 2nd lowest in 2016 of 4.02 million km2.

Ice Melt Outlook The peak days of daily melt are past. From now to minimum, on average daily extent loss will gradually but erratically reduce until the minimum. 
____________________________________________________________
Due to events my postings will also be erratic as to timing.

[gerontocrat]

NSIDC Total Area as at 20 August 2019 (5 day trailing average) 3,062,345 km2

On this day area loss again extremely below average

Total Area           3,062,345    km2       -536,371    km2   <   2010's average. -414,732    km2   <   2018 -1,352,168    km2   <   2000's average.           Total Area Change   -13    k   loss Peripheral Seas    1    k   gain Central Seas__   -13    k   loss Other Seas___   -0    k   loss           Peripheral Seas          Bering _______    0    k   gain Baffin  Bay____    0    k   gain Greenland____    1    k   gain Barents ______   -0    k   loss           CAB Seas          Beaufort_____   -6    k   loss CAA_________    3    k   gain East Siberian__   -9    k   loss Central Arctic_    1    k   gain           Kara_________    2    k   gain Laptev_______   -4    k   loss Chukchi______   -0    k   loss           Other Seas          Okhotsk______   -0    k   loss St Lawrence___    -    k   loss Hudson Bay___   -0    k   loss

- Area loss 13 k, 37 k less than the 2010's average area loss of 50 k on this day,
- Total area 2nd Lowest, 112 k LESS than 2016, and 211 k MORE than 2012.

On this day area loss much less than 2012 and 2016
while NSIDC daily extent loss also very low at 28 k.
________________________________________________________________________
Outlook
We are now well into the period of reducing and very variable daily area loss that that will slide to zero by mid-September. Some postings on the melting thread spoke about how current winds dispersing ice might reduce area and extent data measurements - maybe only temporarily.

But end of season wobbles makes comments out-of-date almost before they are typed. Just sit back and watch.

[Alphabet Hotel]

NSIDC daily extent

[Shared Humanity]

2nd or 3rd place for SIE and SIA more and more likely. Whatever it is, the ice is in terrible shape and the impact on NH weather will continue. I will be intently interested in how the approaching freeze season behaves.

[gerontocrat]

2nd or 3rd place for SIE and SIA more and more likely. Whatever it is, the ice is in terrible shape and the impact on NH weather will continue. I will be intently interested in how the approaching freeze season behaves.

And some time or other we might be getting something like definitive physical measures of sea ice thickness from the lasers on ICESat-2. The lasers will measure the actual height of the sea ice and of the ocean, and from the freeboard the thickness can be calculated.

Could be this winter or some time next year.

https://nsidc.org/data/icesat-2/products/level-3b

Gridded Monthly Sea Ice Freeboard (ATL20),
Sea Surface Height: Ice-Covered Ocean (ATL21)
ATL20 and ATL21 will consist of gridded estimates of sea ice freeboard and sea surface height (ice-covered ocean) for both Arctic and Southern Oceans. ATL20 will report sea ice freeboard from all ICESat-2 tracks between the beginning and the end of each month. ATL21 will provide monthly averages of sea surface height from all ICESat-2 tracks between the beginning and the end of each month. Both data sets will be gridded at 25 km or 12.5 km (TBD) and mapped onto a planimetric grid using the SSM/I Polar Stereographic Projection equations.