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Messages - gerontocrat

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1
Arctic sea ice / Re: The 2020/2021 freezing season
« on: October 27, 2020, 06:34:29 PM »

The final image makes a 'prediction' for the freeze-over date for the Laptev. The image takes a copy of the blue line from 2012, colors it gold and moves it over exactly horizontally until it extends the most recent 2020 date. A dotted green line is then dropped from the intercept down to the calendar date, intercepting it in late November, almost a full month later than the previous record from 2012.
The assumption is that the Laptev will freeze to maximum almost verically/.

If you look at its neighbour, the Kara, you will see that while this used to be the case in that sea, it no longer is, at least not every year. This tends to show especially in the sea ice area graphs. Sometimes ice growth to maximum is in fits and starts, and sometimes the winter maximum is not 100%.

My speculation is that one year the Laptev is going to go the same way - but in which year?

2
Permafrost / Re: Permafrost general science thread
« on: October 27, 2020, 04:57:15 PM »
But we have to wait for a peer-reviewd paper next year to find out how whoops! it really is.

https://www.theguardian.com/science/2020/oct/27/sleeping-giant-arctic-methane-deposits-starting-to-release-scientists-find
'Sleeping giant' Arctic methane deposits starting to release, scientists find
Exclusive: expedition discovers new source of greenhouse gas off East Siberian coast has been triggered

Quote
Scientists have found evidence that frozen methane deposits in the Arctic Ocean – known as the “sleeping giants of the carbon cycle” – have started to be released over a large area of the continental slope off the East Siberian coast, the Guardian can reveal.

High levels of the potent greenhouse gas have been detected down to a depth of 350 metres in the Laptev Sea near Russia, prompting concern among researchers that a new climate feedback loop may have been triggered that could accelerate the pace of global heating.

The slope sediments in the Arctic contain a huge quantity of frozen methane and other gases – known as hydrates. Methane has a warming effect 80 times stronger than carbon dioxide over 20 years. The United States Geological Survey has previously listed Arctic hydrate destabilisation as one of four most serious scenarios for abrupt climate change.

The international team onboard the Russian research ship R/V Akademik Keldysh said most of the bubbles currently are dissolving in the water but methane levels at the surface are four to eight times what would normally be expected and this is venting into the atmosphere.

At this moment, there is unlikely to be any major impact on global warming, but the point is that this process has now been triggered. This East Siberian slope methane hydrate system has been perturbed and the process will be ongoing,” said the Swedish scientist Örjan Gustafsson of Stockholm University in a satellite call from the vessel.

The scientists – who are part of a multi-year International Shelf Study Expedition – stressed their findings are preliminary. The scale of methane releases will not be confirmed until they return, analyse the data and have their studies published in a peer-reviewed journal.

But the discovery of potentially destabilised slope frozen methane raises concerns that a new tipping point has been reached that could increase the speed of global heating. The Arctic is considered ground zero in the debate about the vulnerability of frozen methane deposits in the ocean. With the Arctic temperature now rising more than twice as fast as the global average, the question of when – or even whether – they will be released into the atmosphere has been a matter of considerable uncertainty in climate computer models.

The 60-member team on the Akademik Keldysh believe they are the first to observationally confirm the methane release is already under way across a wide area of the slope about 600km offshore.


The latest discovery potentially marks the third source of methane emissions from the region. Semiletov, who has been studying this area for two decades, has previously reported the gas is being released from the shelf of the Arctic – the biggest of any sea.

For the second year in a row, his team have found crater-like pockmarks in the shallower parts of the Laptev Sea and East Siberian Sea that are discharging bubble jets of methane, which is reaching the sea surface at levels tens to hundreds of times higher than normal. This is similar to the craters and sinkholes reported from inland Siberian tundra earlier this autumn.

3
Consequences / Re: Hurricane Season 2020
« on: October 27, 2020, 04:41:22 PM »
meanwhile,

https://edition.cnn.com/2020/10/26/asia/vietnam-typhoon-molave-evacuate-intl-hnk/index.html
Vietnam is preparing to evacuate nearly 1.3 million people ahead of Typhoon Molave, which is expected to make landfall on Wednesday.

Typhoon Molave
, with wind speeds of 125 kilometers (77 miles) per hour and gusts of up to 150 kph (93.2 mph), left the main Philippine island of Luzon earlier on Monday, with heavy rain causing seven landslides and floods in 11 areas, the disaster agency said.
There were no reports of casualties, but 12 fishermen at sea failed to return to Catanduanes province off the country's eastern coast. Molave, known as Typhoon Quinta in the Philippines, was the 17th typhoon to hit the country this year.
It will be the fourth storm to hit Vietnam in a tumultuous month, during which floods and landslides have killed 130 people and left 20 missing in the central region. When Molave makes landfall, wind speeds are forecast to reach 135 kph (83.8 mph).

4
Consequences / Re: Hurricane Season 2020
« on: October 27, 2020, 04:34:32 PM »
Tropical storm Zeta is expected to hookup with winter storm Billy.  The two storms will converge around Nashville and soak the entire area from the Tennessee Valley through the mid-Atlantic states.
And come next Tuesday, the remains may be raining from Iceland to Novaya Zemla

5
How average can you get? https://cryospherecomputing.tk/ from Nico Sun

Until it's not average any more - at least in North America.

6
Consequences / Re: COVID-19
« on: October 27, 2020, 02:06:21 PM »
Tumbling numbers of pregnancies and marriages in Japan during the coronavirus pandemic are likely to intensify a demographic crisis in the rapidly ageing nation, Reuters reports.

Japan has the most aged society in the world, with more than 35% of its population expected to be 65 and over by 2050, a trend that poses risks for economic growth and straining government finances.

I know this is OT here but this drives me nuts. Transitioning to a stable population structure means passing a larger cohort through old age. It has to happen sometime or your population grows infinitely. I understand that it can be done more or less rapidly, but I guarantee you it's not going to get easier to tackle the demographic transition later in this century. Get on with it!

Today you read that an ageing population means economic disaster as the percentage of the population of working age decreases..
Tomorrow you read that AI + robots mean vastly increased unemployment of those of working age.

& has absolutely nowt to do with sorting out how to manage covid-19.




7
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: October 27, 2020, 01:46:01 PM »
NSIDC Extent graphs - compare and contrast the Beaufort with the Laptev and the ESS

8
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: October 27, 2020, 01:25:23 PM »
NSIDC Total AREA as at 26-Oct-2020 (5 day trailing average) 4,573,553 KM2         
         
Total Area         
 4,573,553    km2      
-1,384,287    km2   <   2010's average.
-482,669    km2   <   2019
-2,443,110    km2   <   2000's average.
         
Total Change    89    k   gain
Peripheral Seas    13    k   gain
Central Seas___    76    k   gain
         
Peripheral Seas         
Okhotsk______   -0    k   loss
Bering _______    1    k   gain
Hudson Bay___    0    k   gain
Baffin  Bay____    3    k   gain
St Lawrence___    -    k   loss
Greenland____    9    k   gain
Barents ______    0    k   gain
         
Central Arctic  Ocean Seas         
Chukchi______    6    k   gain
Beaufort_____    6    k   gain
CAA_________    18    k   gain
East Siberian__    11    k   gain
Central Arctic_    21    k   gain
Laptev_______    7    k   gain
Kara_________    6    k   gain
         
Sea ice area gain on this day 89 k, 36 k less than the 2010's average gain of 125 k         
         
- 2020 area is at position #1 in the satellite record.         
- 2020 Area is 1,384 k less than the 2010's average         
- 2020 Area is 2,443 k less than the 2000's average         
- 2020 Area is 464 k less than 2016         
- 2020 Area is 483 k less than 2019          
- 2020 Area is 1,154 k less than 2012         
___________________________________________         
NSIDC Total EXTENT as at 26-Oct-2020 (5 day trailing average) 5,705,794 KM2         
         
NSIDC Sea ice EXTENT gain on this day 101 k, 28 k less than the 2010's average gain of 129k         
         
- 2020 EXTENT is at position #1 in the satellite record.         
- 2020 EXTENT is 1,770 k less than the 2010's average         
- 2020 EXTENT is 2,744 k less than the 2000's average         
- 2020 EXTENT is 1088 k less than 2016         
- 2020 EXTENT is 644 k less than 2019          
- 2020 EXTENT is 1,548 k less than 2012   
_________________________________________
Area and extent daily gains continue to gradually increase but below the 10 year average.      
___________________________________________         
Note: Click an image for full-size         

9
Arctic sea ice / Re: Global sea ice area and extent data
« on: October 27, 2020, 12:28:15 PM »
JAXA GLOBAL SEA ICE EXTENT:  23,807,091 KM2 as at 26-Oct-2020

- Extent gain on this day 85k, 7 k more than the average gain on this day (of the last 10 years) of 78k,
- Extent gain from minimum on this date is 7.09 million km2, 1.58 million km2, 18.2% less than the 10 year average gain of 8.67 million km2.
- Extent is at position #2 in the satellite record
- 2020 Extent is  -0.18 million km2 LESS than 2019,
On average 95.4% of sea ice gain from minimum to maximum done, and 9 days to maximum

Projections of the Unknown Quantity. (Table JAXA-AA1)

Average remaining sea ice gain (of the last 10 years) would produce a maximum in November 2020 of 24.23 million km2, 0.47 million km2 above the 2016 record low maximum of 23.76 million km2.
___________________________________________________
The false maximum was reached on the 28th June. Extent losses finished at the false minimum of early September. We are now in the late run of extent  gains to  the “maximum maximum” for the year in late October/early November.

N.B. In 2016 the maximum was reached on the 7th July. i.e. the November maximum was less than the “false” maximum.
___________________________________________________
If Antractic sea ice loss remains low and arctic sea ice daily gains accelerate (catch-up from the late refreeze) the global maximum could be delayed.
___________________________________________________
N.B. Click an image once for full-size

10
Antarctica / Re: Sea Ice Extent around Antarctica
« on: October 27, 2020, 12:26:05 PM »
JAXA ANTARCTIC SEA ICE EXTENT:  18,037,921 KM2 as at 26-Oct-2020

- Extent loss on this day 51k, 0 k more than the average loss on this day (of the last 10 years) of 51k,
- Extent loss from maximum on this date is 0.82 million km2, 0.28 million km2, (25%) less than the 10 year average of 1.10 million km2.
- Extent is at position #34 in the satellite record of which 19 lower values are in the years before 2000
- Extent is  1,273 k MORE than 2016
- Extent is  517 k MORE than 2017
- Extent is  952 k MORE than 2018
- Extent is  676 k MORE than 2019
- Extent is  407 k MORE than the 1980's Average

- On average 6.9% of ice loss  from maximum to minimum done, and 118 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 3.17 million km2, 1.03 million km2 above the 2017 record low minimum of 2.15 million km2.
___________________________________________________________
N.B. Click on image  for full-size

11
Arctic sea ice / Re: 365 day average extent poll
« on: October 27, 2020, 12:04:58 PM »
The 365 day trailing average continues to reduce at an accelerating rate. Given that 2019 daily extent gains continue to be very high this could continue for at least a few days more.

However, from around the 5th November daily gains in 2019 moderated. If, on the other hand, 2020 extent gains sharply increase due to the catch-up expected due to the very late late re-freeze, 2020 extent could catch up with 2019 very quickly indeed.

A reminder - it is the amount by which 2020 extent is lower than 2019 that determines the rate by which this average reduces.

A record low 365 day average in mid November is now a tantalising possibility.

12
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: October 27, 2020, 11:44:12 AM »
JAXA ARCTIC SEA ICE EXTENT:  5,769,170 KM2 as at 26-Oct-2020

- Extent gain on this day 136k, 7 k more than the average gain on this day (of the last 10 years) of 129k,
- Extent gain from minimum on this date is 2,214 k, which is 976 k, 31% less than the 10 year average of 3,190 k.
- Extent is at position #1 in the satellite record
- Extent is  853 k LESS than 2019,
- Extent is  969 k LESS than 2016,
- Extent is  1,332 k LESS than 2012
- Extent is  1,557 k LESS than 2007
- Extent is  1,719 k LESS than the 2010's Average
_____________________________________________
On average 32.2% of extent gains  from minimum to maximum done, and 136 days to maximum

Projections. (Table JAXA-Arc1)

Average remaining extent gain (of the last 10 years) would produce a maximum in March 2021 of 12.50 million km2, 1.38 million km2 below the March 2017 record low maximum of 13.88 million km2.

For the 2020-21 maximum NOT to be a record low, remaining extent gain has to be more than 20.5% above the average remaining extent gain of the last 10 years. This is greater than any of at least the last 13 years.
_________________________________________
3 days of extent gains above average gains but below 2019 gains, so 2020 is #1 by a greater amount.
However, gains in 2016 were very low at this time, which means that 2020 extent is starting to play catchup with 2016, which was lowest from the 27th October.

_______________________________________________________________
N.B. Click on image to enlarge

13
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: October 26, 2020, 01:34:08 PM »
NSIDC Total AREA as at 25-Oct-2020 (5 day trailing average) 4,484,565 KM2         
         
Total Area         
 4,484,565    km2      
-1,348,456    km2   <   2010's average.
-426,042    km2   <   2019
-2,413,213    km2   <   2000's average.
         
Total Change    75    k   gain
Peripheral Seas    12    k   gain
Central Seas___    63    k   gain
         
Peripheral Seas         
Okhotsk______    2    k   gain
Bering _______    0    k   gain
Hudson Bay___    0    k   gain
Baffin  Bay____    3    k   gain
St Lawrence___    -    k   loss
Greenland____    7    k   gain
Barents ______    0    k   gain
         
Central Arctic  Ocean Seas         
Chukchi______    5    k   gain
Beaufort_____   -7    k   loss
CAA_________    17    k   gain
East Siberian__    9    k   gain
Central Arctic_    29    k   gain
Laptev_______    6    k   gain
Kara_________    5    k   gain
         
Sea ice area gain on this day 75 k, 48 k less than the 2010's average gain of 123 k         
         
- 2020 area is at position #1 in the satellite record.         
- 2020 Area is 1,348 k less than the 2010's average         
- 2020 Area is 2,413 k less than the 2000's average         
- 2020 Area is 454 k less than 2016         
- 2020 Area is 426 k less than 2019          
- 2020 Area is 1,130 k less than 2012         
___________________________________________         
NSIDC Total EXTENT as at 25-Oct-2020 (5 day trailing average) 5,604,882 KM2         
         
NSIDC Sea ice EXTENT gain on this day 98 k, 31 k less than the 2010's average gain of 129k         
         
- 2020 EXTENT is at position #1 in the satellite record.         
- 2020 EXTENT is 1,742 k less than the 2010's average         
- 2020 EXTENT is 2,736 k less than the 2000's average         
- 2020 EXTENT is 1089 k less than 2016         
- 2020 EXTENT is 569 k less than 2019          
- 2020 EXTENT is 1,527 k less than 2012         
___________________________________________         
Note: Click an image for full-size         

15
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: October 25, 2020, 01:46:19 PM »
NSIDC Total AREA as at 24-Oct-2020 (5 day trailing average) 4,409,158 KM2         
         
Total Area         
 4,409,158    km2      
-1,300,448    km2   <   2010's average.
-391,426    km2   <   2019
-2,365,653    km2   <   2000's average.
         
Total Change    64    k   gain
Peripheral Seas    8    k   gain
Central Seas___    55    k   gain
         
Peripheral Seas         
Okhotsk______    2    k   gain
Bering _______   -0    k   loss
Hudson Bay___   -1    k   loss
Baffin  Bay____    1    k   gain
St Lawrence___    -    k   loss
Greenland____    6    k   gain
Barents ______   -0    k   loss
         
Central Arctic  Ocean Seas         
Chukchi______   -2    k   loss
Beaufort_____   -10    k   loss
CAA_________    16    k   gain
East Siberian__    6    k   gain
Central Arctic_    37    k   gain
Laptev_______    5    k   gain
Kara_________    3    k   gain
         
Sea ice area gain on this day 64 k, 58 k less than the 2010's average gain of 122 k         
         
- 2020 area is at position #1 in the satellite record.         
- 2020 Area is 1,300 k less than the 2010's average         
- 2020 Area is 2,366 k less than the 2000's average         
- 2020 Area is 406 k less than 2016         
- 2020 Area is 391 k less than 2019          
- 2020 Area is 1,082 k less than 2012         
___________________________________________         
NSIDC Total EXTENT as at 24-Oct-2020 (5 day trailing average) 5,507,039 KM2         
         
NSIDC Sea ice EXTENT gain on this day 67 k, 60 k less than the 2010's average gain of 127k         
         
- 2020 EXTENT is at position #1 in the satellite record.         
- 2020 EXTENT is 1,710 k less than the 2010's average         
- 2020 EXTENT is 2,722 k less than the 2000's average         
- 2020 EXTENT is 1058 k less than 2016         
- 2020 EXTENT is 524 k less than 2019          
- 2020 EXTENT is 1,474 k less than 2012         
___________________________________________         
Note: Click an image for full-size         

16
Arctic sea ice / Re: Global sea ice area and extent data
« on: October 25, 2020, 09:57:09 AM »
JAXA GLOBAL SEA ICE EXTENT:  23,638,104 KM2 as at 24-Oct-2020

- Extent gain on this day 143k, 89 k more than the average gain on this day (of the last 10 years) of 54k,
- Extent gain from minimum on this date is 6.92 million km2, 1.61 million km2, 18.9% less than the 10 year average gain of 8.53 million km2.
- Extent is at position #2 in the satellite record
- 2020 Extent is  -0.05 million km2 LESS than 2019,
On average 93.9% of sea ice gain from minimum to maximum done, and 11 days to maximum

Projections of the Unknown Quantity. (Table JAXA-AA1)

Average remaining sea ice gain (of the last 10 years) would produce a maximum in November 2020 of 24.20 million km2, 0.43 million km2 above the 2016 record low maximum of 23.76 million km2.
___________________________________________________
The false maximum was reached on the 28th June. Extent losses finished at the false minimum of early September. We are now in the late run of extent  gains to  the “maximum maximum” for the year in late October/early November.

N.B. In 2016 the maximum was reached on the 7th July. i.e. the November maximum was less than the “false” maximum.
___________________________________________________
And so ends global sea ice extent's brief sojourn as #1, scuppered by..
- arctic sea ice extent gain doubles to an above average 144k,
- antarctic sea ice extent loss stalls at a miserable 1k.
___________________________________________________
N.B. Click an image once for full-size

17
Antarctica / Re: Sea Ice Extent around Antarctica
« on: October 25, 2020, 09:44:47 AM »

I made another plot, now for the sector closest to the Antarctic coast, from 60S to 70S. Thus excluding the Antarctic land mass.
The trend is the same, pronounced cooling over 40 years.

And when you add the post by interstitial you start to see a more complete story of maybe why the sea ice average is barely changed over the last 40 years but warmer ocean water is attacking  ice shelves and glaciers, to a considerable extent from underneath.

I wonder what a 50 to 60 South graph would look like.

meanwhile...
JAXA ANTARCTIC SEA ICE EXTENT:  18,156,720 KM2 as at 24-Oct-2020

- Extent loss on this day 1k, 63 k less than the average loss on this day (of the last 10 years) of 64k,
- Extent loss from maximum on this date is 0.70 million km2, 0.31 million km2, (30%) less than the 10 year average of 1.01 million km2.
- Extent is at position #34 in the satellite record of which 19 lower values are in the years before 2000
- Extent is  1,232 k MORE than 2016
- Extent is  658 k MORE than 2017
- Extent is  967 k MORE than 2018
- Extent is  600 k MORE than 2019
- Extent is  417 k MORE than the 1980's Average

- On average 6.3% of ice loss  from maximum to minimum done, and 120 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 3.18 million km2, 1.03 million km2 above the 2017 record low minimum of 2.15 million km2.
___________________________________________
Antarctic sea ice melt has currently stalled.
___________________________________________________________
N.B. Click on image  for full-size

18
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: October 25, 2020, 09:20:22 AM »
JAXA ARCTIC SEA ICE EXTENT:  5,481,384 KM2 as at 24-Oct-2020

- Extent gain on this day 144k, 26 k more than the average gain on this day (of the last 10 years) of 118k,
- Extent gain from minimum on this date is 1,927 k, which is 1,053 k, 35% less than the 10 year average of 2,979 k.
- Extent is at position #1 in the satellite record
- Extent is  651 k LESS than 2019,
- Extent is  1,121 k LESS than 2016,
- Extent is  1,556 k LESS than 2012
- Extent is  1,539 k LESS than 2007
- Extent is  1,754 k LESS than the 2010's Average
_____________________________________________
On average 29.9% of extent gains  from minimum to maximum done, and 138 days to maximum

Projections. (Table JAXA-Arc1)

Average remaining extent gain (of the last 10 years) would produce a maximum in March 2021 of 12.47 million km2, 1.41 million km2 below the March 2017 record low maximum of 13.88 million km2.

For the 2020-21 maximum NOT to be a record low, remaining extent gain has to be more than 20.2% above the average remaining extent gain of the last 10 years. This is greater than any of at least the last 13 years.
_____________________________________________________
I didn't see that one coming - a doubling of the daily extent gain to well above average, and on the same day of the year 2019 daily extent gains started to go through the roof.
_______________________________________________________________
N.B. Click on image to enlarge

19
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: October 24, 2020, 02:28:44 PM »
NSIDC Total AREA as at 23-Oct-2020 (5 day trailing average) 4,345,534 KM2         
         
Total Area         
 4,345,534    km2      
-1,241,599    km2   <   2010's average.
-383,531    km2   <   2019
-2,303,434    km2   <   2000's average.
         
Total Change    59    k   gain
Peripheral Seas    6    k   gain
Central Seas___    53    k   gain
         
Peripheral Seas         
Okhotsk______    1    k   gain
Bering _______    1    k   gain
Hudson Bay___   -0    k   loss
Baffin  Bay____   -0    k   loss
St Lawrence___    -    k   loss
Greenland____    5    k   gain
Barents ______    0    k   gain
         
Central Arctic  Ocean Seas         
Chukchi______   -3    k   loss
Beaufort_____   -6    k   loss
CAA_________    13    k   gain
East Siberian__    2    k   gain
Central Arctic_    40    k   gain
Laptev_______    5    k   gain
Kara_________    3    k   gain
         
Sea ice area gain on this day 59 k, 65 k less than the 2010's average gain of 124 k         
         
- 2020 area is at position #1 in the satellite record.         
- 2020 Area is 1,242 k less than the 2010's average         
- 2020 Area is 2,303 k less than the 2000's average         
- 2020 Area is 338 k less than 2016         
- 2020 Area is 384 k less than 2019          
- 2020 Area is 998 k less than 2012         
___________________________________________         
NSIDC Total EXTENT as at 23-Oct-2020 (5 day trailing average) 5,439,684 KM2         
         
NSIDC Sea ice EXTENT gain on this day 68 k, 60 k less than the 2010's average gain of 128k         
         
- 2020 EXTENT is at position #1 in the satellite record.         
- 2020 EXTENT is 1,651 k less than the 2010's average         
- 2020 EXTENT is 2,676 k less than the 2000's average         
- 2020 EXTENT is 987 k less than 2016         
- 2020 EXTENT is 478 k less than 2019          
- 2020 EXTENT is 1,345 k less than 2012   
____________________________________________
Note that NSIDC daily extent gain is accelerating.
Up by 92 k on the 22nd, 139k on the 23rd.
___________________________________________         
Note: Click an image for full-size         

20
Antarctica / Re: Sea Ice Extent around Antarctica
« on: October 24, 2020, 12:26:44 PM »
Quoting the temperature data for 60 to 90 degrees South can be misleading when using it to comment on Antarctic sea ice.

The area of 60 to 90 South is about 34 million km2.
The area of the Antarctic Continent is about 14 million km2, with coastal temperatures averaging about -10 celsius, and at high elevations of the interior averaging at around -60 celsius. The 60 to 90 average temperatures are thus dominated by the continental temperatures. The climate of the surrounding ocean is thus vastly different from the continental climate.

This is even more pronounced at this time of year, when the sea ice edge is between 55 and 65 degrees south. Here it is the Antarctic Circumpolar Current that is important.

21
Arctic sea ice / Re: Global sea ice area and extent data
« on: October 24, 2020, 10:35:48 AM »
JAXA GLOBAL SEA ICE EXTENT:  23,495,336 KM2 as at 23-Oct-2020

- Extent gain on this day 62k, 8 k more than the average gain on this day (of the last 10 years) of 54k,
- Extent gain from minimum on this date is 6.78 million km2, 1.70 million km2, 20.1% less than the 10 year average gain of 8.48 million km2.
- Extent is at position #1 in the satellite record
- 2020 Extent is  -0.10 million km2 LESS than 2019,
On average 93.3% of sea ice gain from minimum to maximum done, and 12 days to maximum

Projections of the Unknown Quantity. (Table JAXA-AA1)

Average remaining sea ice gain (of the last 10 years) would produce a maximum in November 2020 of 24.11 million km2, 0.35 million km2 above the 2016 record low maximum of 23.76 million km2.
___________________________________________________
The false maximum was reached on the 28th June. Extent losses finished at the false minimum of early September. We are now in the late run of extent  gains to  the “maximum maximum” for the year in late October/early November.

N.B. In 2016 the maximum was reached on the 7th July. i.e. the November maximum was less than the “false” maximum.
___________________________________________________
Very low Antarctic daily sea ice loss plus an uptick in Arctic daily sea ice extent gain (though still well below average) results in an at average global sea ice extent gain.

It looks very possible that in the next day or two global sea ice extent will lose it's current #1 position.
___________________________________________________
N.B. Click an image once for full-size

22
Antarctica / Re: Sea Ice Extent around Antarctica
« on: October 24, 2020, 10:25:50 AM »
JAXA ANTARCTIC SEA ICE EXTENT:  18,158,062 KM2 as at 23-Oct-2020

- Extent loss on this day 12k, 47 k less than the average loss on this day (of the last 10 years) of 59k,
- Extent loss from maximum on this date is 0.70 million km2, 0.26 million km2, (27%) less than the 10 year average of 0.96 million km2.
- Extent is at position #34 in the satellite record of which 19 lower values are in the years before 2000
- Extent is  1,141 k MORE than 2016
- Extent is  683 k MORE than 2017
- Extent is  884 k MORE than 2018
- Extent is  530 k MORE than 2019
- Extent is  367 k MORE than the 1980's Average

- On average 6.0% of ice loss  from maximum to minimum done, and 121 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 3.12 million km2, 0.97 million km2 above the 2017 record low minimum of 2.15 million km2.
_____________________________________________________
This very low sea ice extent loss has changed total extent in the last 3 days from 29th to 34th lowest, or 9th highest, in the 42 year satellite record.
___________________________________________________________
N.B. Click on image  for full-size

23
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: October 24, 2020, 09:56:09 AM »
JAXA ARCTIC SEA ICE EXTENT:  5,337,274 KM2 as at 23-Oct-2020

- Extent gain on this day 74k, 39 k less than the average gain on this day (of the last 10 years) of 113k,
- Extent gain from minimum on this date is 1,782 k, which is 1,093 k, 38% less than the 10 year average of 2,876 k.
- Extent is at position #1 in the satellite record
- Extent is  631 k LESS than 2019,
- Extent is  1,161 k LESS than 2016,
- Extent is  1,586 k LESS than 2012
- Extent is  1,552 k LESS than 2007
- Extent is  1,780 k LESS than the 2010's Average
_____________________________________________
On average 28.8% of extent gains  from minimum to maximum done, and 139 days to maximum

Projections. (Table JAXA-Arc1)

Average remaining extent gain (of the last 10 years) would produce a maximum in March 2021 of 12.44 million km2, 1.44 million km2 below the March 2017 record low maximum of 13.88 million km2.

For the 2020-21 maximum NOT to be a record low, remaining extent gain has to be more than 20.3% above the average remaining extent gain of the last 10 years. This is greater than any of at least the last 13 years.
_______________________________________________________________
N.B. Click on image to enlarge

24
Glaciers / Re: Glaciers worldwide decline faster than ever
« on: October 23, 2020, 07:01:09 PM »
Glaciers retreat whodunnit - it was us.

https://tc.copernicus.org/preprints/tc-2020-265/tc-2020-265.pdf
On the attribution of industrial-era glacier mass loss to anthropogenic climate change
Quote
Abstract.
Around the world, small ice caps and glaciers have been losing mass and retreating during the industrial era. Estimates are that this has contributed approximately 30 % of the observed sea-level rise over the same period. It is important to understand the relative importance of natural and anthropogenic components of this mass loss. One recent study concluded that the best estimate of the anthropogenic contribution over the industrial era was only 25 %, implying a predominantly natural cause. Here we show that the fraction of the anthropogenic contribution to the total mass loss of a given glacier depends only on the magnitudes and rates of the natural and anthropogenic components of climate change, and on the glacier's response time. We consider climate change over the past millennium using synthetic scenarios, paleoclimate reconstructions, numerical climate simulations, and instrumental observations. We use these climate histories to drive a glacier model that can represent a wide range of glacier response times to evaluate the anthropogenic contribution to glacier mass loss. The slow cooling over the preceding millennium, followed by the rapid anthropogenic warming of the industrial era means that, over the full range of response times for small ice caps and glaciers, the central estimate of the anthropogenic component of the mass loss is essentially 100 %. Our results bring assessments of attribution of glacier mass loss into alignment with assessments of others aspects of climate change, such as global-mean temperature. Furthermore, these results reinforce the scientific and public understanding of centennial-scale glacier retreat as an unambiguous consequence of human activity.

25
Consequences / Re: COVID-19
« on: October 23, 2020, 03:51:36 PM »
https://www.worldometers.info/coronavirus/#countries

World and USA graphs.

7 day trailing averages of daily new cases and deaths on the rise.

26
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: October 23, 2020, 03:13:01 PM »
Graphs from NSIDC Data

The gains in sea ice area and extent have been driven mostly by the Beaufort and the Central Arctic.

Beaufort sea ice extent is now only 70k below the maximum of 940k, and daily extent gain is already slowing by a lot, so will be a non-player in a week or so.
Central Arctic sea ice extent is just 250k below the maximum of 3.25 million km2. At the current daily increase of just under 20k, about 2 weeks to go.

Beaufort sea ice area is just over 200k below the maximum of 940k, and daily area gain is also already slowing significantly.  From now likely to be a minor element of area gain
Central Arctic sea ice area is just 600k below the maximum of 3.25 million km2. The daily sea ice area gain on this day was a massive 48k, so could be a major part of sea ice area fains for the next two weeks or so.

There is little or no sign as yet of other seas entering the fast lane of re-freeze.


 

27
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: October 23, 2020, 02:32:16 PM »
NSIDC Total AREA as at 22-Oct-2020 (5 day trailing average) 4,286,263 KM2         
         
Total Area         
 4,286,263    km2      
-1,176,387    km2   <   2010's average.
-374,737    km2   <   2019
-2,237,771    km2   <   2000's average.
         
Total Change    71    k   gain
Peripheral Seas    6    k   gain
Central Seas___    65    k   gain
         
Peripheral Seas         
Okhotsk______    1    k   gain
Bering _______   -0    k   loss
Hudson Bay___   -0    k   loss
Baffin  Bay____   -0    k   loss
St Lawrence___    -    k   loss
Greenland____    6    k   gain
Barents ______    0    k   gain
         
Central Arctic  Ocean Seas         
Chukchi______   -1    k   loss
Beaufort_____    8    k   gain
CAA_________    7    k   gain
East Siberian__    2    k   gain
Central Arctic_    44    k   gain
Laptev_______    3    k   gain
Kara_________    2    k   gain
         
Sea ice area gain on this day 71 k, 53 k less than the 2010's average gain of 124 k         
         
- 2020 area is at position #1 in the satellite record.         
- 2020 Area is 1,176 k less than the 2010's average         
- 2020 Area is 2,238 k less than the 2000's average         
- 2020 Area is 272 k less than 2016         
- 2020 Area is 375 k less than 2019          
- 2020 Area is 906 k less than 2012         
___________________________________________         
NSIDC Total EXTENT as at 22-Oct-2020 (5 day trailing average) 5,372,009 KM2         
         
NSIDC Sea ice EXTENT gain on this day 48 k, 84 k less than the 2010's average gain of 132k         
         
- 2020 EXTENT is at position #1 in the satellite record.         
- 2020 EXTENT is 1,591 k less than the 2010's average         
- 2020 EXTENT is 2,631 k less than the 2000's average         
- 2020 EXTENT is 900 k less than 2016         
- 2020 EXTENT is 433 k less than 2019          
- 2020 EXTENT is 1,228 k less than 2012         
___________________________________________         
Note: Click an image for full-size         

28
Arctic sea ice / Re: 365 day average extent poll
« on: October 23, 2020, 01:12:58 PM »
The 365 day trailing average continues to reduce at an accelerating rate. Given that 2019 daily extent gains are about to rocket upwards, this continue for at least a few days more. A reminder - it is the amount by which 2020 extent is lower than 2019 that determines the rate by which this average reduces.

A record low 365 day average in November is now a possibility, though perhaps not a probability.

29
Arctic sea ice / Re: Global sea ice area and extent data
« on: October 23, 2020, 12:32:56 PM »
JAXA GLOBAL SEA ICE EXTENT:  23,432,991 KM2 as at 22-Oct-2020

- Extent gain on this day 89k, 0 k more than the average gain on this day (of the last 10 years) of 89k,
- Extent gain from minimum on this date is 6.71 million km2, 1.70 million km2, 20.2% less than the 10 year average gain of 8.41 million km2.
- Extent is at position #1 in the satellite record
- 2020 Extent is  -0.16 million km2 LESS than 2019,
On average 92.7% of sea ice gain from minimum to maximum done, and 13 days to maximum

Projections of the Unknown Quantity. (Table JAXA-AA1)

Average remaining sea ice gain (of the last 10 years) would produce a maximum in November 2020 of 24.10 million km2, 0.34 million km2 above the 2016 record low maximum of 23.76 million km2.
___________________________________________________
The false maximum was reached on the 28th June. Extent losses finished at the false minimum of early September. We are now in the late run of extent  gains to  the “maximum maximum” for the year in late October/early November.

N.B. In 2016 the maximum was reached on the 7th July. i.e. the November maximum was less than the “false” maximum.
___________________________________________________
An unusual Antarctic daily sea ice gain plus and uptick in Arctic daily sea ice extent gain (though still well below average) results in an at average global sea ice extent gain.
___________________________________________________
N.B. Click an image once for full-size

30
Antarctica / Re: Sea Ice Extent around Antarctica
« on: October 23, 2020, 12:21:38 PM »
JAXA ANTARCTIC SEA ICE EXTENT:  18,169,884 KM2 as at 22-Oct-2020

- Extent GAIN on this day 18k, 63 k less than the average LOSS on this day (of the last 10 years) of 45k,
- Extent loss from maximum on this date is 0.69 million km2, 0.21 million km2, (24%) less than the 10 year average of 0.91 million km2.
- Extent is at position #32 in the satellite record of which 18 lower values are in the years before 2000
- Extent is  1,064 k MORE than 2016
- Extent is  661 k MORE than 2017
- Extent is  819 k MORE than 2018
- Extent is  452 k MORE than 2019
- Extent is  335 k MORE than the 1980's Average

- On average 5.7% of ice loss  from maximum to minimum done, and 122 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 3.07 million km2, 0.92 million km2 above the 2017 record low minimum of 2.15 million km2.
________________________________________________
Daily Antarctic sea ice extent losses change from being very low to reversing into a sea ice extent gain on this day. As a result total extent drops from 29th lowest to 32nd lowest
___________________________________________________________
N.B. Click on image  for full-size

31
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: October 23, 2020, 12:09:21 PM »
JAXA ARCTIC SEA ICE EXTENT:  5,263,107 KM2 as at 22-Oct-2020

- Extent gain on this day 71k, 64 k less than the average gain on this day (of the last 10 years) of 135k,
- Extent gain from minimum on this date is 1,708 k, which is 1,048 k, 38% less than the 10 year average of 2,757 k.
- Extent is at position #1 in the satellite record
- Extent is  615 k LESS than 2019,
- Extent is  1,123 k LESS than 2016,
- Extent is  1,546 k LESS than 2012
- Extent is  1,450 k LESS than 2007
- Extent is  1,741 k LESS than the 2010's Average
_____________________________________________
On average 27.6% of extent gains  from minimum to maximum done, and 140 days to maximum

Projections. (Table JAXA-Arc1)

Average remaining extent gain (of the last 10 years) would produce a maximum in March 2021 of 12.48 million km2, 1.40 million km2 below the March 2017 record low maximum of 13.88 million km2.

For the 2020-21 maximum NOT to be a record low, remaining extent gain has to be more than 19.4% above the average remaining extent gain of the last 10 years
_______________________________________________________________
N.B. Click on image to enlarge

32
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: October 22, 2020, 02:09:13 PM »
NSIDC Total AREA as at 21-Oct-2020 (5 day trailing average) 4,214,858 KM2         
         
Total Area         
 4,214,858    km2      
-1,124,258    km2   <   2010's average.
-373,269    km2   <   2019
-2,181,640    km2   <   2000's average.
         
Total Change    74    k   gain
Peripheral Seas    7    k   gain
Central Seas___    67    k   gain
         
Peripheral Seas         
Okhotsk______    0    k   gain
Bering _______   -1    k   loss
Hudson Bay___    0    k   gain
Baffin  Bay____    0    k   gain
St Lawrence___    -    k   loss
Greenland____    7    k   gain
Barents ______   -0    k   loss
         
Central Arctic  Ocean Seas         
Chukchi______    2    k   gain
Beaufort_____    17    k   gain
CAA_________    3    k   gain
East Siberian__    4    k   gain
Central Arctic_    38    k   gain
Laptev_______    2    k   gain
Kara_________    2    k   gain
         
Sea ice area gain on this day 74 k, 45 k less than the 2010's average gain of 119 k         
         
- 2020 area is at position #1 in the satellite record.         
- 2020 Area is 1,124 k less than the 2010's average         
- 2020 Area is 2,182 k less than the 2000's average         
- 2020 Area is 236 k less than 2016         
- 2020 Area is 373 k less than 2019          
- 2020 Area is 821 k less than 2012         
___________________________________________         
NSIDC Total EXTENT as at 21-Oct-2020 (5 day trailing average) 5,323,749 KM2         
         
NSIDC Sea ice EXTENT gain on this day 38 k, 90 k less than the 2010's average gain of 128k         
         
- 2020 EXTENT is at position #1 in the satellite record.         
- 2020 EXTENT is 1,508 k less than the 2010's average         
- 2020 EXTENT is 2,563 k less than the 2000's average         
- 2020 EXTENT is 808 k less than 2016         
- 2020 EXTENT is 365 k less than 2019          
- 2020 EXTENT is 1085 k less than 2012
______________________________________
Area gain increases - but still well below average..         
___________________________________________         
Note: Click an image for full-size         

33
Consequences / Re: Climate change, the ocean, agriculture, and FOOD
« on: October 22, 2020, 01:55:29 PM »
The EU has voted for BAU. The consequences of intensifying industrial farming for wildlife and just about everything else, including us, will be profound. I was tempted to post this in the Holocene Extinction thread.

Let's have another round of drinks in "The Last Chance Saloon".

https://www.theguardian.com/environment/2020/oct/21/greta-thunberg-accuses-meps-of-surrender-on-climate-and-environment
Greta Thunberg accuses MEPs of 'surrender on climate and environment'
European parliament votes to continue payments to farmers with no green conditions attached

Quote
Greta Thunberg, the Swedish school strike pioneer and environmental activist, has accused MEPs of surrendering on the climate and environment by voting in favour of a watered-down reform of the EU’s common agricultural policy.

The European parliament voted late on Wednesday in favour of proposals put forward by the main political groups that will continue 60% of the current direct payments to farmers with weak or non-existent green conditions attached.

The changes backed by the parliament weaken an already heavily criticised proposal from the European commission on reform of the CAP, which accounts for one-third of the EU budget.

MEPs will continue to vote on a host of issues around future reforms up until Friday, as parliament sets its position before negotiations with the member states and the European commission.

Thunberg tweeted: “While media was reporting on ‘names of vegan hot dogs’ the EU parliament signed away €387bn [£350bn] to a new agricultural policy that basically means surrender on climate & environment. No awareness means no pressure and accountability so the outcome is no surprise. They just don’t care.”

Bas Eickhout, a Green MEP, said: “Climate change and ecological breakdown pose a severe threat to farming, our food system and our future on this planet and yet a large number of MEPs are wilfully ignoring the enormous scale of the problem.

“Unfortunately, the EPP, Socialists and Renew groups have watered down the already weak proposals of the commission by continuing with 60% of direct payments with very weak conditions.

“Without binding targets for more climate protection, less pesticides in the fields and less antibiotics in livestock farming, the CAP will stand as the very antithesis to the purpose of the Green Deal,” Eickhout said.

34
The forum / Re: Forum Decorum
« on: October 22, 2020, 01:19:13 PM »
'I don´t really see the point of diaries.' .. thank goodness the early explorers and others thought otherwise . This forum is little more than a modern diary . And I'm sure you won't be forced to write one or read anyone else's ..   :) b.c.
"Dear Diary,
Today I woke up and got up out of bed earlier than usual. Not only did I have a shower but also had a shave. This lunchtime I am going to. the local town to have a coffee with a friend

etc... etc...."

Most diaries are bloody boring.
Not many of us are a Samuel Johnson.

35
Arctic sea ice / Re: The 2020/2021 freezing season
« on: October 22, 2020, 01:00:13 PM »
You read all about it first on the Arctic Sea Ice Forum....

https://www.theguardian.com/world/2020/oct/22/alarm-as-arctic-sea-ice-not-yet-freezing-at-latest-date-on-record
Alarm as Arctic sea ice not yet freezing at latest date on record
Delayed freeze in Laptev Sea could have knock-on effects across polar region, scientists say

Quote
For the first time since records began, the main nursery of Arctic sea ice in Siberia has yet to start freezing in late October.

The delayed annual freeze in the Laptev Sea has been caused by freakishly protracted warmth in northern Russia and the intrusion of Atlantic waters, say climate scientists who warn of possible knock-on effects across the polar region.

Ocean temperatures in the area recently climbed to more than 5C above average, following a record breaking heatwave and the unusually early decline of last winter’s sea ice.

The trapped heat takes a long time to dissipate into the atmosphere, even at this time of the year when the sun creeps above the horizon for little more than an hour or two each day.

Graphs of sea-ice extent in the Laptev Sea, which usually show a healthy seasonal pulse, appear to have flat-lined. As a result, there is a record amount of open sea in the Arctic.

“The lack of freeze-up so far this fall is unprecedented in the Siberian Arctic region,” said Zachary Labe, a postdoctoral researcher at Colorado State University. He says this is in line with the expected impact of human-driven climate change.

“2020 is another year that is consistent with a rapidly changing Arctic. Without a systematic reduction in greenhouse gases, the likelihood of our first ‘ice-free’ summer will continue to increase by the mid-21st century,’ he wrote in an email to the Guardian.

This year’s Siberian heatwave was made at least 600 times more likely by industrial and agricultural emissions, according to an earlier study.

The warmer air temperature is not the only factor slowing the formation of ice. Climate change is also pushing more balmy Atlantic currents into the Arctic and breaking up the usual stratification between warm deep waters and the cool surface. This also makes it difficult for ice to form.

“This continues a streak of very low extents. The last 14 years, 2007 to 2020, are the lowest 14 years in the satellite record starting in 1979,” said Walt Meier, senior research scientist at the US National Snow and Ice Data Center. He said much of the old ice in the Arctic is now disappearing, leaving thinner seasonal ice. Overall the average thickness is half what it was in the 1980s. The downward trend is likely to continue until the Arctic has its first ice-free summer, said Meier. The data and models suggest this will occur between 2030 and 2050. “It’s a matter of when, not if,” he added.

Scientists are concerned the delayed freeze could amplify feedbacks that accelerate the decline of the ice cap. It is already well known that a smaller ice sheet means less of a white area to reflect the sun’s heat back into space. But this is not the only reason the Arctic is warming more than twice as fast as the global average.

The Laptev Sea is known as the birthplace of ice, which forms along the coast there in early winter, then drifts westward carrying nutrients across the Arctic, before breaking up in the spring in the Fram Strait between Greenland and Svalbard. If ice forms late in the Laptev, it will be thinner and thus more likely to melt before it reaches the Fram Strait. This could mean fewer nutrients for Arctic plankton, which will then have a reduced capacity to draw down carbon dioxide from the atmosphere.

More open sea also means more turbulence in the upper layer of the Arctic ocean, which draws up more warm water from the depths.

Dr Stefan Hendricks, a sea ice physics specialist at the Alfred Wegener Institute, said the sea ice trends are grim but not surprising. “It is more frustrating than shocking. This has been forecast for a long time, but there has been little substantial response by decision-makers.”

36
Arctic sea ice / Re: Global sea ice area and extent data
« on: October 22, 2020, 11:19:41 AM »
JAXA GLOBAL SEA ICE EXTENT:  23,344,192 KM2 as at 21-Oct-2020

- Extent gain on this day 46k, 21 k less than the average gain on this day (of the last 10 years) of 67k,
- Extent gain from minimum on this date is 6.62 million km2, 1.70 million km2, 20.4% less than the 10 year average gain of 8.32 million km2.
- Extent is at position #1 in the satellite record
- 2020 Extent is  -0.16 million km2 LESS than 2019,
On average 91.7% of sea ice gain from minimum to maximum done, and 14 days to maximum

Projections of the Unknown Quantity. (Table JAXA-AA1)

Average remaining sea ice gain (of the last 10 years) would produce a maximum in November 2020 of 24.10 million km2, 0.34 million km2 above the 2016 record low maximum of 23.76 million km2.
___________________________________________________
The false maximum was reached on the 28th June. Extent losses finished at the false minimum of early September. We are now in the late run of extent  gains to  the “maximum maximum” for the year in late October/early November.

N.B. In 2016 the maximum was reached on the 7th July. i.e. the November maximum was less than the “false” maximum.
___________________________________________________
Antarctic sea ice melt still very slow.
Arctic sea ice extent ticked up, but well below average.

Global sea ice extent stays lowest for a 2nd day, 27 days in total for the year.
___________________________________________________
N.B. Click an image once for full-size

37
Antarctica / Re: Sea Ice Extent around Antarctica
« on: October 22, 2020, 10:35:51 AM »
Gero, do you have a 365-day average trend graph for the Antarctic? I'd expect that if you do, then it'd probably show a flat trend like the monthly average graphs, but would be interested all the same.
Yes

Flat it is not.

38
Antarctica / Re: Sea Ice Extent around Antarctica
« on: October 22, 2020, 10:12:23 AM »
JAXA ANTARCTIC SEA ICE EXTENT:  18,152,051 KM2 as at 21-Oct-2020

- Extent gain on this day 18k, 31 k more than the average gain on this day (of the last 10 years) of 49k,
- Extent gain from minimum on this date is 0.71 million km2, 0.86 million km2, -(15.3%) less than the 10 year average of -0.18 million km2.
- Extent is at position #29 in the satellite record of which 16 lower values are in the years before 2000
- Extent is  978 k MORE than 2016
- Extent is  614 k MORE than 2017
- Extent is  713 k MORE than 2018
- Extent is  408 k MORE than 2019
- Extent is  279 k MORE than the 1980's Average

- On average 5.4% of ice gain from minimum to maximum done, and 123 days to maximum

Projections. (Table JAXA-Ant1)

Average remaining freeze (of the last 10 years) would produce a maximum in Sept 2020 of 3.00 million km2, 0.86 million km2 above the 2017 record low maximum of 18.06 million km2.
___________________________________________________________
N.B. Click on image  for full-size
___________________________________________________________
Blurb during Melting Season
JAXA ANTARCTIC SEA ICE EXTENT:  18,152,051 KM2 as at 21-Oct-2020

- Extent loss on this day 18k, 31 k less than the average loss on this day (of the last 10 years) of 49k,
- Extent loss from maximum on this date is 0.71 million km2, 0.15 million km2, (18%) less than the 10 year average of 0.86 million km2.
- Extent is at position #29 in the satellite record of which 16 lower values are in the years before 2000
- Extent is  978 k MORE than 2016
- Extent is  614 k MORE than 2017
- Extent is  713 k MORE than 2018
- Extent is  408 k MORE than 2019
- Extent is  279 k MORE than the 1980's Average

- On average 5.4% of ice loss  from maximum to minimum done, and 123 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 3.00 million km2, 0.86 million km2 above the 2017 record low minimum of 2.15 million km2.
___________________________________________________________
N.B. Click on image  for full-size

39
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: October 22, 2020, 10:05:36 AM »
JAXA Extent data
With only 10 days to month end, the October Monthly Average is now guaranteed to be a record low by around half a million km2, or 1 million km2 below the linear trend value for the year.

40
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: October 22, 2020, 09:48:08 AM »
JAXA ARCTIC SEA ICE EXTENT:  5,192,141 KM2 as at 21-Oct-2020

- Extent gain on this day 64k, 53 k less than the average gain on this day (of the last 10 years) of 117k,
- Extent gain from minimum on this date is 1,637 k, which is 987 k, 38% less than the 10 year average of 2,624 k.
- Extent is at position #1 in the satellite record
- Extent is  565 k LESS than 2019,
- Extent is  1,073 k LESS than 2016,
- Extent is  1,389 k LESS than 2012
- Extent is  1,358 k LESS than 2007
- Extent is  1,677 k LESS than the 2010's Average
_____________________________________________
On average 26.3% of extent gains  from minimum to maximum done, and 141 days to maximum

Projections. (Table JAXA-Arc1)

Average remaining extent gain (of the last 10 years) would produce a maximum in March 2021 of 12.54 million km2, 1.34 million km2 below the March 2017 record low maximum of 13.88 million km2.

For the 2020-21 maximum NOT to be a record low, remaining extent gain has to be more than 18.2% above the average remaining extent gain of the last 10 years
_______________________________________________________________
N.B. Click on image to enlarge

41
Consequences / Re: Places becoming more livable
« on: October 21, 2020, 11:09:51 PM »
While high northerly latitudes could indeed be relative winners, permafrost degradation could be one counter-feedback,
Methinks it might be advisable change "could be" to "will be"

It is not just a case of getting warmer and the land drying out and bingo, you've got cropland.

Quote
Permafrost ranges in thickness from 1500 m in Siberia and 740 m in Alaska to just a few meters in its lower latitude extremes. Typically thicknesses range from 100 to 800 m in continuous permafrost, 25 to 100 m in discontinuous permafrost, and 10 to 50 m in sporadic permafrost.
https://www.britannica.com/science/permafrost/Ice-content
Quote
World estimates of the amount of ice in permafrost vary from 200,000 to 500,000 cubic kilometres (49,000 to 122,000 cubic miles), or less than 1 percent of the total volume of the Earth. It has been estimated that 10 percent by volume of the upper 3 metres of permafrost on the northern Coastal Plain of Alaska is composed of foliated ground ice (ice wedges). Taber ice is the most extensive type of ground ice, and in places it represents 75 percent of the ground by volume. It is calculated that the pore and Taber ice content in the depth between 0.5 and 3 metres (surface to 0.5 metre is seasonally thawed) is 61 percent by volume, and between 3 and 9 metres it is 41 percent. The total amount of pingo ice is less than 0.1 percent of the permafrost. The total ice content in the permafrost of the Arctic Coastal Plain of Alaska is estimated to be 1,500 cubic kilometres, and below 9 metres most of that is present as pore ice.

Thermokarst formations
The thawing of permafrost creates thermokarst topography, an uneven surface that contains mounds, sinkholes, tunnels, caverns, and steep-walled ravines caused by melting of ground ice. The hummocky ground surface resembles karst topography in limestone areas. Thawing may result from artificial or natural removal of vegetation or from a warming climate.

Thawed depressions filled with water (thaw lakes, thermokarst lakes, cave-in lakes) are widespread in permafrost areas, especially in those underlain with perennially frozen silt. They may occur on hillsides or even on hilltops and are good indicators of ice-rich permafrost. Locally, deep thermokarst pits 6 metres deep and 9 metres across may form as ground ice melts. These openings may exist as undetected caverns for many years before the roof collapses. Such collapses in agricultural or construction areas are real dangers. Thermokarst mounds are polygonal or circular hummocks 3 to 15 metres in diameter and 0.3 to 2.5 metres high that are formed as a polygonal network of ice melts and leaves the inner-ice areas as mounds.

Pingos
The most spectacular landforms associated with permafrost are pingos, small ice-cored circular or elliptical hills of frozen sediments or even bedrock, 3 to more than 60 metres high and 15 to 450 metres in diameter. Pingos are widespread in the continuous permafrost zone and are quite conspicuous because they rise above the tundra. They are much less conspicuous in the forested area of the discontinuous permafrost zone. They are generally cracked on top with summit craters formed by melting ice. There are two types of pingos, based on origin. The closed-system type forms in level areas when unfrozen groundwater in a thawed zone becomes confined on all sides by permafrost, freezes, and heaves the frozen overburden to form a mound. This type is larger and occurs mainly in tundra areas of continuous permafrost. The open-system type is generally smaller and forms on slopes when water beneath or within the permafrost penetrates the permafrost under hydrostatic pressure. A hydrolaccolith (water mound) forms and freezes, heaving the overlying frozen and unfrozen ground to produce a mound.

42
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: October 21, 2020, 08:08:46 PM »
& here is the CAA extent graph.

43
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: October 21, 2020, 08:04:48 PM »
Some thoughts on when and where re-freeze will happen in the next few days or weeks (continued)
(based on NSIDC Extent data)


From the above post I speculate that any sgnificant acceleration in extent gains this re-freeze season must come from just 5 seas -  - Kara, Laptev, ESS, Chukchi and the CAA -

The Kara and Laptev regions are currently stalled at minimum.
Last year the Kara went to maximum almost verically, starting about now. But on average earlier and not so spectacularly fast,  and in 2016, extent gains only started in November and were not completed until the New Year.

The Laptev has a history of very fast extent gains to maximum, but will this year be different?

The ESS looked as if the rapid re-freeze had started, but now has stalled.

The Chukchi was re-freezing even faster, but has also stalled,

The CAA extent gains were average, but in recent days there has been a significant drop, but maybe as the Beaufort closes up there will be a final rush to completion. (see next post for graph).
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OVERALL - I see little prospect of a major increase in extent gains for the remainder of October. November - perhaps it's all about the Atlantic front including the ESS- salinity, the (compromised?) halocline, the amount of remaining available ocean heat.

That was my speculation that belongs to me

44
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: October 21, 2020, 07:42:19 PM »
Some thoughts on when and where re-freeze will happen in the next few days or weeks
(based on NSIDC Extent data)


Most extent gains, though very low, are occuring in the High Arctic (first graph), and mostly from just two regions***,
- the Central Arctic (2nd graph),
- the Beaufort sea (3rd graph).

Central Arctic sea ice extent is just under 300k below maximum, and is increasing at around 12k a day. Remaining open water is mostly from the Barents to the Laptev, Not much sign of rapid extent gains there.

Beaufort sea ice extent gains have been at an impressive 20k+ per day for some time. But the sea is nearly full up ice, just 100k to the maximum of 940k. So in a few day it is likely that the Beaufort will no longer provide sgnificant extentb gains.

Could the Peripheral regional seas (Graph 4) see a major accelerationn in sea ice gains?
So far extent gains have averaged well below 10 k per day, and on average only get up to around 50k per day from mid-November.

We are just left with 5 High Arctic Regions*** to consider - Kara, Laptev, ESS, Chukchi and the CAA - see next post.
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*** I was recently told off for referring to the Central Arctic as the Central Arctic Sea (CAS) even though I was referring to the NSIDC defined area of 3.224 million km2, not the larger Central Arctic Basin of 4.4 million as used by Wipneus in his volume and other analayses (which goes back to the areas defined by the late lamented Cryosphere Today) .

So I had a ponder - neither definitions correpsond to any political map of the Arctic Seas. So what does NSIDC call them? NSIDC in their MASIE website refers to them all as REGIONS.


45
Consequences / Re: COVID-19
« on: October 21, 2020, 06:44:13 PM »
https://www.worldometers.info/coronavirus/#countries

ITALY and UK daily New cases and Deaths graphs. (7 day trailing average)

I have had to change the Daily New cases scale on both these graphs due to the very fast increases in the daily data.
I had thought that could wait until November but... events, events.

Let us hope the same will not apply to the daily deaths scale.

46
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: October 21, 2020, 02:43:35 PM »
More than a hint that the re- freeze may be on a trend to be delayed (as various science papers have predicted)?
We could then expect that peak daily ice growth will move into late November?
I make no predictions on when re-freeze moves into high gear. All I can say is that the data below says - not yet.

NSIDC Total AREA as at 20-Oct-2020 (5 day trailing average) 4,141,321 KM2         
         
Total Area         
 4,141,321    km2      
-1,079,184    km2   <   2010's average.
-379,746    km2   <   2019
-2,126,380    km2   <   2000's average.
         
Total Change    52    k   gain
Peripheral Seas    3    k   gain
Central Seas___    49    k   gain
         
Peripheral Seas         
Okhotsk______   -1    k   loss
Bering _______   -1    k   loss
Hudson Bay___   -1    k   loss
Baffin  Bay____   -0    k   loss
St Lawrence___    -    k   loss
Greenland____    6    k   gain
Barents ______   -0    k   loss
         
Central Arctic  Ocean Seas         
Chukchi______    3    k   gain
Beaufort_____    22    k   gain
CAA_________    1    k   gain
East Siberian__    3    k   gain
Central Arctic_    19    k   gain
Laptev_______    0    k   gain
Kara_________    1    k   gain
         
Sea ice area gain on this day 52 k, 62 k less than the 2010's average gain of 114 k         
         
- 2020 area is at position #1 in the satellite record.         
- 2020 Area is 1,079 k less than the 2010's average         
- 2020 Area is 2,126 k less than the 2000's average         
- 2020 Area is 207 k less than 2016         
- 2020 Area is 380 k less than 2019          
- 2020 Area is 725 k less than 2012         
___________________________________________         
NSIDC Total EXTENT as at 20-Oct-2020 (5 day trailing average) 5,285,827 KM2         
         
NSIDC Sea ice EXTENT gain on this day 35 k, 93 k less than the 2010's average gain of 128k         
         
- 2020 EXTENT is at position #1 in the satellite record.         
- 2020 EXTENT is 1,417 k less than the 2010's average         
- 2020 EXTENT is 2,491 k less than the 2000's average         
- 2020 EXTENT is 724 k less than 2016         
- 2020 EXTENT is 288 k less than 2019          
- 2020 EXTENT is 943 k less than 2012         
___________________________________________         
Note: Click an image for full-size         


47
Arctic sea ice / Re: Global sea ice area and extent data
« on: October 21, 2020, 11:21:28 AM »
JAXA GLOBAL SEA ICE EXTENT:  23,297,849 KM2 as at 20-Oct-2020

- Extent gain on this day 23k, 28 k less than the average gain on this day (of the last 10 years) of 51k,
- Extent gain from minimum on this date is 6.58 million km2, 1.68 million km2, 20.4% less than the 10 year average gain of 8.26 million km2.
- Extent is at position #1 in the satellite record
- 2020 Extent is  -0.15 million km2 LESS than 2019,
On average 90.9% of sea ice gain from minimum to maximum done, and 15 days to maximum

Projections of the Unknown Quantity. (Table JAXA-AA1)

Average remaining sea ice gain (of the last 10 years) would produce a maximum in November 2020 of 24.12 million km2, 0.36 million km2 above the 2016 record low maximum of 23.76 million km2.
___________________________________________________
The false maximum was reached on the 28th June. Extent losses finished at the false minimum of early September. We are now in the late run of extent  gains to  the “maximum maximum” for the year in late October/early November.

N.B. In 2016 the maximum was reached on the 7th July. i.e. the November maximum was less than the “false” maximum.
___________________________________________________
In the Arctic on this day a low extent gain of 62k.
In the Antarctic on this day a low extent loss of 38k.

Result, a low 23k global sea ice extent gain, and global sea ice extent now lowest in the satellite record.

The current projected maximum of 24.1 million km2 is 2nd lowest in the satellite record, and is entirely due to the record low Arctic sea ice extent

___________________________________________________
N.B. Click an image once for full-size

48
Antarctica / Re: Sea Ice Extent around Antarctica
« on: October 21, 2020, 10:50:55 AM »
JAXA ANTARCTIC SEA ICE EXTENT:  18,170,098 KM2 as at 20-Oct-2020

- Extent loss on this day 38k, 20 k less than the average loss on this day (of the last 10 years) of 58k,
- Extent loss from maximum on this date is 0.69 million km2, 0.14 million km2, (16%) less than the 10 year average of 0.83 million km2.
- Extent is at position #29 in the satellite record of which 16 lower values are in the years before 2000
- Extent is  958 k MORE than 2016
- Extent is  572 k MORE than 2017
- Extent is  627 k MORE than 2018
- Extent is  347 k MORE than 2019
- Extent is  260 k MORE than the 1980's Average

- On average 5.2% of ice loss  from maximum to minimum done, and 124 days to minimum

Projections. (Table JAXA-Ant1)

Average remaining melt (of the last 10 years) would produce a minimum in Feb 2021 of 2.97 million km2, 0.83 million km2 above the 2017 record low minimum of 2.15 million km2.
___________________________________________________________
N.B. Click on image  for full-size

49
Arctic sea ice / Re: 365 day average extent poll
« on: October 21, 2020, 10:39:13 AM »
Confidence in a record low 365 day trailing average in 2020 increases day by day.

50
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: October 21, 2020, 10:18:55 AM »
JAXA ARCTIC SEA ICE EXTENT:  5,127,751 KM2 as at 20-Oct-2020

- Extent gain on this day 62k, 47 k less than the average gain on this day (of the last 10 years) of 109k,
- Extent gain from minimum on this date is 1,573 k, which is 929 k, 37% less than the 10 year average of 2,502 k.
- Extent is at position #1 in the satellite record
- Extent is  498 k LESS than 2019,
- Extent is  1,025 k LESS than 2016,
- Extent is  1,221 k LESS than 2012
- Extent is  1,121 k LESS than 2007
- Extent is  1,625 k LESS than the 2010's Average
_____________________________________________
On average 25.1% of extent gains  from minimum to maximum done, and 142 days to maximum

Projections. (Table JAXA-Arc1)

Average remaining extent gain (of the last 10 years) would produce a maximum in March 2021 of 12.59 million km2, 1.28 million km2 below the March 2017 record low maximum of 13.88 million km2.
_________________________________________
If you look at graph Arc-4, you will see that at this time last year 2019 was lowest in the satellite record by an astonishing amount. To see two years in a row like this is very unusual.

And if you look at the table Arc-3, you will see that at this time in 2018, 2018 was lowest (just).

More than a hint that the re- freeze may be on a trend to be delayed (as various science papers have predicted)?
_______________________________________________________________
N.B. Click on image to enlarge

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