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gerontocrat

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Re: 2019 sea ice area and extent data
« Reply #100 on: January 27, 2019, 07:34:49 PM »
NSIDC Total Area as at 26 January 2019 (5 day trailing average) 12,450,449  km2

Total Area         
 12,450,449    km2      
 368,740    km2   >    2010's average.
 617,367    k   >   2018
-159,400    k   <    2000's average.
         
Total Gain    20    k   
Peripheral Seas    4    k   gain
Central Seas__    11    k   gain
Other Seas___    5    k   gain
         
Peripheral Seas         
Bering _______   -0    k   loss
Baffin  Bay____   -5    k   loss
Greenland____   -4    k   loss
Barents ______    13    k   gain
         
CAB Seas         
Beaufort_____    1    k   gain
CAA_________    1    k   gain
East Siberian__    2    k   gain
Central Arctic_   -1    k   loss
         
Kara_________    9    k   gain
Laptev_______    0    k   gain
Chukchi______   -2    k   loss
         
Other Seas         
Okhotsk______    8    k   gain
St Lawrence___   -5    k   loss
Hudson Bay___    2    k   gain
Area gain 20 k, 7k less than the 2010's average for the day.

Other stuff

GFS indicates that overall the Arctic temperature anomaly remains close to zero and -1 degrees for the next week or more. This disguises the highly variable +ve and -ve anomalies at various times over the various regions of the Arctic.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

Juan C. García

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Re: 2019 sea ice area and extent data
« Reply #101 on: January 28, 2019, 04:58:02 AM »
[ADS NIPR VISHOP (JAXA)] Arctic Sea Ice Extent.

January 27th, 2019:
     13,449,609 km2, an increase of 79,404 km2::)
     2019 is now the 8th lowest on record (and close to become the 10th.  8) ).
Which is the best answer to Sep-2012 ASI lost (compared to 1979-2000)?
50% [NSIDC Extent] or
73% [PIOMAS Volume]

Volume is harder to measure than extent, but 3-dimensional space is real, 2D's hide ~50% thickness gone.
-> IPCC/NSIDC trends [based on extent] underestimate the real speed of ASI lost.

Juan C. García

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Re: 2019 sea ice area and extent data
« Reply #102 on: January 28, 2019, 05:03:33 AM »
[ADS NIPR VISHOP (JAXA)] Arctic Sea Ice Extent.

January 27th, 2019:
     13,449,609 km2, an increase of 79,404 km2::)
     2019 is now the 8th lowest on record (and close to become the 10th.  8) ).

This abnormal increase, could be a problem with the sensor today?
Which is the best answer to Sep-2012 ASI lost (compared to 1979-2000)?
50% [NSIDC Extent] or
73% [PIOMAS Volume]

Volume is harder to measure than extent, but 3-dimensional space is real, 2D's hide ~50% thickness gone.
-> IPCC/NSIDC trends [based on extent] underestimate the real speed of ASI lost.

AmbiValent

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Re: 2019 sea ice area and extent data
« Reply #103 on: January 28, 2019, 08:16:28 AM »
This abnormal increase, could be a problem with the sensor today?
Last time, grey areas were counted towards extent, so I think that abnormal increase isn't actually there.
Bright ice, how can you crack and fail? How can the ice that seemed so mighty suddenly seem so frail?

gerontocrat

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Re: 2019 sea ice area and extent data
« Reply #104 on: January 28, 2019, 11:00:13 AM »
JAXA ARCTIC EXTENT 13,449,609 km2(January 27, 2019)

- Extent gain 79k, 77k more than average gain on this day.
- Extent is 8th lowest in the satellite record,
- Freezing to date from minimum is 36 k (0.4%) ABOVE the 10 year average extent gain,
- On average (last 10 years) 89.9 % of the increase in extent from min to max is done.
- On average (last 10 years) 43 days to maximum (11th March)

The outcome from using the 10 year average extent gain from now is a maximum extent of 14.37 million km2 (480k > 2018).

Other Stuff
GFS indicates that overall the Arctic temperature anomaly remains between +1 and -1 degrees for the next week or more. This disguises even more the highly variable +ve and -ve anomalies at various times over the various regions of the Arctic.

The 79k increase is not unprecedented by any means (see graph Arc2 attached) but is a bit of a mystery (see next post).
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

gerontocrat

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Re: 2019 sea ice area and extent data
« Reply #105 on: January 28, 2019, 11:07:47 AM »
The 79k increase is not unprecedented. The VISHOP /JAXA image for the day does not show the missing bits as in that from the University of Bremen.

But where did the increase occur? The temperature map for the 27th from GFS shows +ve temperature anomalies for all the areas of the peripheral seas where remaining sea ice extent gain is happening.

So a bit of a mystery.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

Juan C. García

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Re: 2019 sea ice area and extent data
« Reply #106 on: January 28, 2019, 12:23:05 PM »
JAXA ARCTIC EXTENT 13,449,609 km2(January 27, 2019)

- Extent gain 79k, 77k more than average gain on this day.
There has to be a typing mistake here. Maybe 47k more than average gain?

The 79k increase is not unprecedented by any means (see graph Arc2 attached) but is a bit of a mystery (see next post).
Thank you for your answer, Gerontocrat.  :)
Which is the best answer to Sep-2012 ASI lost (compared to 1979-2000)?
50% [NSIDC Extent] or
73% [PIOMAS Volume]

Volume is harder to measure than extent, but 3-dimensional space is real, 2D's hide ~50% thickness gone.
-> IPCC/NSIDC trends [based on extent] underestimate the real speed of ASI lost.

uniquorn

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Re: 2019 sea ice area and extent data
« Reply #107 on: January 28, 2019, 12:40:17 PM »
amsr2-uhh jan26 and 27 for reference.
Wipneus' charts don't show any drastic changes in the Bering though. https://sites.google.com/site/arcticseaicegraphs/regional
« Last Edit: January 28, 2019, 12:54:44 PM by uniquorn »

gerontocrat

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Re: 2019 sea ice area and extent data
« Reply #108 on: January 28, 2019, 02:44:56 PM »
NSIDC Total Area as at 27 January 2019 (5 day trailing average) 12,471,393  km2

Total Area         
 12,471,393    km2      
 363,696    km2   >    2010's average.
 603,210    k   >   2018
-156,889    k   <    2000's average.
         
Total Gain    21    k   
Peripheral Seas    4    k   gain
Central Seas__    2    k   gain
Other Seas___    15    k   gain
         
Peripheral Seas         
Bering _______   -5    k   loss
Baffin  Bay____   -6    k   loss
Greenland____    2    k   gain
Barents ______    14    k   gain
         
CAB Seas         
Beaufort_____   -1    k   loss
CAA_________    1    k   gain
East Siberian__    1    k   gain
Central Arctic_   -4    k   loss
         
Kara_________    8    k   gain
Laptev_______    0    k   gain
Chukchi______   -3    k   loss
         
Other Seas         
Okhotsk______    17    k   gain
St Lawrence___    1    k   gain
Hudson Bay___   -3    k   loss
Area gain 20 k, 7k less than the 2010's average for the day.

Other stuff

GFS indicates that overall the Arctic temperature anomaly remains between +1 and -1 degrees for the next week or more. This disguises even more the highly variable +ve and -ve anomalies at various times over the various regions of the Arctic. hence sudden changes in gain and loss in peripheral seas (e.g. Bering, Okhotsk, Baffin, Greenland).
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

oren

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Re: 2019 sea ice area and extent data
« Reply #109 on: January 28, 2019, 04:07:21 PM »
JAXA ARCTIC EXTENT 13,449,609 km2(January 27, 2019)

- Extent gain 79k, 77k more than average gain on this day.
There has to be a typing mistake here. Maybe 47k more than average gain?
Not a mistake. Gc quotes the difference from the actual daily average, not from the smooth polynomial approximation of it. The actual daily average fluctuates quite a lot, as can be seen in the chart.
I did wonder in the past what is better to use as quoted baseline, the smoothed or actual average. But luckily for me I'm not the one who has to decide...

gerontocrat

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Re: 2019 sea ice area and extent data
« Reply #110 on: January 28, 2019, 06:04:03 PM »
JAXA ARCTIC EXTENT 13,449,609 km2(January 27, 2019)

- Extent gain 79k, 77k more than average gain on this day.
There has to be a typing mistake here. Maybe 47k more than average gain?
Not a mistake. Gc quotes the difference from the actual daily average, not from the smooth polynomial approximation of it. The actual daily average fluctuates quite a lot, as can be seen in the chart.
I did wonder in the past what is better to use as quoted baseline, the smoothed or actual average. But luckily for me I'm not the one who has to decide...
The interest to me is that a 10 year average shows such high daily variations. When I made the spreadsheet I thought using a 10 year average would do the smoothing for me. It did not so I chucked in the polynomial (x2) to get a clearer view of the trend.

It just shows that an above average gain on one day coinciding with a very low average day's gain can make one blink - the restless ocean springing a little surprise.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

Feeltheburn

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Re: 2019 sea ice area and extent data
« Reply #111 on: January 29, 2019, 04:46:14 AM »
First time NSID over 14,000,000 km2 for 2019.

14,051,000

I wonder if it will be able to hit 15,000,000 for the first time in years?
Feel The Burn!

Juan C. García

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Re: 2019 sea ice area and extent data
« Reply #112 on: January 29, 2019, 05:06:14 AM »
The interest to me is that a 10 year average shows such high daily variations.
The same happened to me, so I decided to stop using the original ADS NIPR average and just look at your data...  ;)

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

January 28th, 2019:
     13,477,989 km2, an increase of 28,380 km2.
     2019 is now the 10th lowest on record.
Which is the best answer to Sep-2012 ASI lost (compared to 1979-2000)?
50% [NSIDC Extent] or
73% [PIOMAS Volume]

Volume is harder to measure than extent, but 3-dimensional space is real, 2D's hide ~50% thickness gone.
-> IPCC/NSIDC trends [based on extent] underestimate the real speed of ASI lost.

Sterks

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Re: 2019 sea ice area and extent data
« Reply #113 on: January 29, 2019, 09:12:58 AM »
JAXA ARCTIC EXTENT 13,449,609 km2(January 27, 2019)

- Extent gain 79k, 77k more than average gain on this day.
There has to be a typing mistake here. Maybe 47k more than average gain?
Not a mistake. Gc quotes the difference from the actual daily average, not from the smooth polynomial approximation of it. The actual daily average fluctuates quite a lot, as can be seen in the chart.
I did wonder in the past what is better to use as quoted baseline, the smoothed or actual average. But luckily for me I'm not the one who has to decide...
I see it as the difference between providing data or information.

gerontocrat

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Re: 2019 sea ice area and extent data
« Reply #114 on: January 29, 2019, 11:27:22 AM »
JAXA ARCTIC EXTENT 13,477,989 km2(January 28, 2019)

- Extent gain 28k, 15k more than average gain on this day.
- Extent is 10th lowest in the satellite record,
- Freezing to date from minimum is 51 k (0.6%) ABOVE the 10 year average extent gain,
- On average (last 10 years) 90.0 % of the increase in extent from min to max is done.
- On average (last 10 years) 42 days to maximum (11th March)

The outcome from using the 10 year average extent gain from now is a maximum extent of 14.38 million km2 (500k > 2017).

Other Stuff
GFS indicates that overall the Arctic temperature anomaly remains between +1 and -1 degrees for the next week or more. This disguises even more the highly variable +ve and -ve anomalies at various times over the various regions of the Arctic.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

AmbiValent

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Re: 2019 sea ice area and extent data
« Reply #115 on: January 29, 2019, 12:16:57 PM »
Is the data the two-day average? Then the one-day error data will affect both days' published values, but the 28k increase would be real, since it exchanged a day with error-less data with another such day. And tomorrow the error should be gone completely.
Bright ice, how can you crack and fail? How can the ice that seemed so mighty suddenly seem so frail?

gerontocrat

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Re: 2019 sea ice area and extent data
« Reply #116 on: January 29, 2019, 02:27:42 PM »
NSIDC Total Area as at 28 January 2019 (5 day trailing average) 12,489,322  km2

         
 Total Area         
 12,489,322    km2      
 358,854    km2   >    2010's average.
 599,319    k   >   2018
-165,841    k   <    2000's average.
         
Total Gain    18    k   
Peripheral Seas    5    k   gain
Central Seas__   -6    k   loss
Other Seas___    19    k   gain
         
Peripheral Seas         
Bering _______   -7    k   loss
Baffin  Bay____   -1    k   loss
Greenland____    2    k   gain
Barents ______    11    k   gain
         
CAB Seas         
Beaufort_____   -3    k   loss
CAA_________    0    k   gain
East Siberian__   -0    k   loss
Central Arctic_   -7    k   loss
         
Kara_________    9    k   gain
Laptev_______    0    k   gain
Chukchi______   -4    k   loss
         
Other Seas         
Okhotsk______    20    k   gain
St Lawrence___    1    k   gain
Hudson Bay___   -3    k   loss
Area gain 18 k, 5k less than the 2010's average for the day.

Other stuff

GFS indicates that overall the Arctic temperature anomaly remains between +1 and -1 degrees for the next week or more. This disguises even more the highly variable +ve and -ve anomalies at various times over the various regions of the Arctic. hence sudden changes in gain and loss in peripheral seas (e.g. Bering, Okhotsk, Baffin, Greenland).

And now extreme warmth in and beyond the Bering Strait reducing area in the Chukchi, Beaufort and Central Arctic seas as well as the Bering..
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

Juan C. García

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Re: 2019 sea ice area and extent data
« Reply #117 on: January 30, 2019, 04:45:59 AM »
[ADS NIPR VISHOP (JAXA)] Arctic Sea Ice Extent.

January 29th, 2019:
     13,474,856 km2, a drop of -3,133 km2.
     2019 is now the 7th lowest on record.

(Seems that there was a sensor problem on Jan 27th, that made noise on 27th and 28th. With this drop, back to normal).
Which is the best answer to Sep-2012 ASI lost (compared to 1979-2000)?
50% [NSIDC Extent] or
73% [PIOMAS Volume]

Volume is harder to measure than extent, but 3-dimensional space is real, 2D's hide ~50% thickness gone.
-> IPCC/NSIDC trends [based on extent] underestimate the real speed of ASI lost.

gerontocrat

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Re: 2019 sea ice area and extent data
« Reply #118 on: January 30, 2019, 07:52:53 AM »
JAXA ARCTIC EXTENT 13,474,856 km2(January 29, 2019)

Was there a sensor error on 27th Jan ? The 79k increase on that day was not that unusual

- Extent loss 3k, 38k less than average gain on this day.
- Extent is 7th lowest in the satellite record,
- Freezing to date from minimum is 13 k (0.1%) ABOVE the 10 year average extent gain,
- On average (last 10 years) 90.4 % of the increase in extent from min to max is done.
- On average (last 10 years) 41 days to maximum (11th March)

The outcome from using the 10 year average extent gain from now is a maximum extent of 14.34 million km2 (460k > 2017 - record low maximum).

Other Stuff
GFS indicates that overall the Arctic temperature anomaly remains between close to zero for the next 4 days and then rises to over +2 degrees in the following week. The highly variable +ve and -ve anomalies at various times over the various regions of the Arctic may become even more extreme.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

gerontocrat

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Re: 2019 sea ice area and extent data
« Reply #119 on: January 30, 2019, 08:14:57 AM »
As I said on the previous post...

GFS indicates that overall the Arctic temperature anomaly remains between close to zero for the next 4 days and then rises to over +2 degrees in the following week. The highly variable +ve and -ve anomalies at various times over the various regions of the Arctic may become even more extreme.

Here is a GIF of temp anomalies over the Arctic for the next week from GFS to show what I mean
"Para a Causa do Povo a Luta Continua!"
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AmbiValent

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Re: 2019 sea ice area and extent data
« Reply #120 on: January 30, 2019, 10:20:21 AM »
JAXA ARCTIC EXTENT 13,474,856 km2(January 29, 2019)

Was there a sensor error on 27th Jan ? The 79k increase on that day was not that unusual

Yes, it was showing as grey "lack of data" in the images of that day.
Bright ice, how can you crack and fail? How can the ice that seemed so mighty suddenly seem so frail?

uniquorn

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Re: 2019 sea ice area and extent data
« Reply #121 on: January 30, 2019, 11:10:53 AM »
amsr2-uhh and jaxa vishop images have been corrected for the 27th

gerontocrat

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Re: 2019 sea ice area and extent data
« Reply #122 on: January 30, 2019, 12:00:24 PM »
amsr2-uhh and jaxa vishop images have been corrected for the 27th
Data on the JAXA file plot_extent_n_v2 (1).csv  not changed yet
"Para a Causa do Povo a Luta Continua!"
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gerontocrat

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Re: 2019 sea ice area and extent data
« Reply #123 on: January 30, 2019, 02:14:17 PM »
NSIDC Total Area as at 29 January 2019 (5 day trailing average) 12,493,988  km2

         
 Total Area         
 12,493,988    km2      
 342,152    km2   >    2010's average.
 596,583    k   >   2018
-193,996    k   <    2000's average.
         
Total Gain    5    k   
Peripheral Seas   -8    k   loss
Central Seas__   -9    k   loss
Other Seas___    21    k   gain
         
Peripheral Seas         
Bering _______   -7    k   loss
Baffin  Bay____   -4    k   loss
Greenland____    1    k   gain
Barents ______    1    k   gain
         
CAB Seas         
Beaufort_____   -3    k   loss
CAA_________   -0    k   loss
East Siberian__   -2    k   loss
Central Arctic_   -4    k   loss
         
Kara_________    4    k   gain
Laptev_______    0    k   gain
Chukchi______   -4    k   loss
         
Other Seas         
Okhotsk______    22    k   gain
St Lawrence___   -1    k   loss
Hudson Bay___    0    k   gain
Area gain 5 k, 16k less than the 2010's average for the day.

Other stuff

GFS indicates that overall the Arctic temperature anomaly remains between close to zero for the next 4 days and then rises to over +2 degrees in the following week. The highly variable +ve and -ve anomalies at various times over the various regions of the Arctic may become even more extreme. Hence sudden changes in gain and loss in peripheral seas (e.g. Bering, Okhotsk, Baffin, Greenland).

And now extreme warmth in and beyond the Bering Strait reducing area in the Chukchi, Beaufort and Central Arctic seas as well as the Bering..
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

uniquorn

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Re: 2019 sea ice area and extent data
« Reply #124 on: January 30, 2019, 05:52:19 PM »
amsr2-uhh and jaxa vishop images have been corrected for the 27th
Data on the JAXA file plot_extent_n_v2 (1).csv  not changed yet
No, possibly the data was correct. The images faulty. Hamburg and Bremen looked different

Stephan

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Re: 2019 sea ice area and extent data
« Reply #125 on: January 30, 2019, 08:25:28 PM »
NSIDC Total Area as at 29 January 2019 (5 day trailing average) 12,493,988  km2


         
Other Seas         
Okhotsk______    22    k   gain
St Lawrence___   -1    k   loss
Hudson Bay___    0    k   gain


If I look at the table, in the last two days only the increase in Okhotsk made up for the overall loss of all the other seas...

Juan C. García

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Re: 2019 sea ice area and extent data
« Reply #126 on: January 31, 2019, 05:39:06 AM »
I am not able to access the ADS NIPR VISHOP website.  :(
If someone else can do it or wait for Gerontocrat.

https://ads.nipr.ac.jp/vishop/#/extent
Which is the best answer to Sep-2012 ASI lost (compared to 1979-2000)?
50% [NSIDC Extent] or
73% [PIOMAS Volume]

Volume is harder to measure than extent, but 3-dimensional space is real, 2D's hide ~50% thickness gone.
-> IPCC/NSIDC trends [based on extent] underestimate the real speed of ASI lost.

uniquorn

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Re: 2019 sea ice area and extent data
« Reply #127 on: January 31, 2019, 11:52:41 AM »
 edit: showing 29th, not updated

gerontocrat

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Re: 2019 sea ice area and extent data
« Reply #128 on: January 31, 2019, 02:08:49 PM »
NSIDC Total Area as at 30 January 2019 (5 day trailing average) 12,505,054  km2

         
 Total Area         
 12,505,054    km2      
 326,737    km2   >    2010's average.
 589,928    k   >   2018
-214,220    k   <    2000's average.
         
Total Gain    11    k   
Peripheral Seas   -15    k   loss
Central Seas__   -6    k   loss
Other Seas___    32    k   gain
         
Peripheral Seas         
Bering _______   -7    k   loss
Baffin  Bay____   -8    k   loss
Greenland____    2    k   gain
Barents ______   -2    k   loss
         
CAB Seas         
Beaufort_____   -0    k   loss
CAA_________   -1    k   loss
East Siberian__   -2    k   loss
Central Arctic_   -4    k   loss
         
Kara_________    3    k   gain
Laptev_______    1    k   gain
Chukchi______   -3    k   loss
         
Other Seas         
Okhotsk______    25    k   gain
St Lawrence___    6    k   gain
Hudson Bay___    1    k   gain
Area gain 11 k, 15k less than the 2010's average for the day.

Other stuff

GFS indicates that overall the Arctic temperature anomaly remains between close to zero for the next 3 days and then rises to over +2 degrees in the following week. The highly variable +ve and -ve anomalies at various times over the various regions of the Arctic may become even more extreme. Hence sudden changes in gain and loss in peripheral seas (e.g. Bering, Okhotsk, Baffin, Greenland).

And now extreme warmth in and beyond the Bering Strait reducing area in the Chukchi, Beaufort and Central Arctic seas as well as the Bering..

Also of note is that without the Okhotsk area gain of 25k there would be an area loss of 14k on this day. (similar spotted by Stephan yesterday).
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Juan C. García

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Re: 2019 sea ice area and extent data
« Reply #129 on: February 01, 2019, 06:23:01 AM »
[ADS NIPR VISHOP (JAXA)] Arctic Sea Ice Extent.

January 30th, 2019:
     13,499,512 km2, an increase of 24,656 km2.
     
January 31th, 2019:
     13,479,877 km2, a drop of -19,635 km2.
     2019 is now the 6th lowest on record.

Which is the best answer to Sep-2012 ASI lost (compared to 1979-2000)?
50% [NSIDC Extent] or
73% [PIOMAS Volume]

Volume is harder to measure than extent, but 3-dimensional space is real, 2D's hide ~50% thickness gone.
-> IPCC/NSIDC trends [based on extent] underestimate the real speed of ASI lost.

gerontocrat

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Re: 2019 sea ice area and extent data
« Reply #130 on: February 01, 2019, 10:36:16 AM »
JAXA ARCTIC EXTENT 13,479,877 km2(January 31, 2019)

- Extent loss 20k, 63k less than average gain of 43 k on this day.
- Extent is 6th lowest in the satellite record,
- Freezing to date from minimum is 68 k (0.7%) ABOVE the 10 year average extent gain,
- On average (last 10 years) 91.2 % of the increase in extent from min to max is done.
- On average (last 10 years) 39 days to maximum (11th March)

The outcome from using the 10 year average extent gain from now is a maximum extent of 14.26 million km2 (380k > 2017's record low maximum). This is in contrast with using a polynomial trend line projection, which produces a max of around 13.75 million km2 on the 21st February. The Perils of Prediction.

Other Stuff
GFS indicates that overall the Arctic temperature anomaly remains between close to zero for the next 4 days and then rises to over +2 degrees in the following week. The highly variable +ve and -ve anomalies at various times over the various regions of the Arctic may become even more extreme.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

gerontocrat

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Re: 2019 sea ice area and extent data
« Reply #131 on: February 01, 2019, 02:27:33 PM »
NSIDC Total Area as at 31 January 2019 (5 day trailing average) 12,507,869  km2

         
Total Area         
 12,507,869    km2      
 298,987    km2   >    2010's average.
 554,389    k   >   2018
-242,036    k   <    2000's average.
         
Total Gain    3    k   
Peripheral Seas   -15    k   loss
Central Seas__   -7    k   loss
Other Seas___    25    k   gain
         
Peripheral Seas         
Bering _______   -4    k   loss
Baffin  Bay____    4    k   gain
Greenland____   -1    k   loss
Barents ______   -13    k   loss
         
CAB Seas         
Beaufort_____    1    k   gain
CAA_________   -1    k   loss
East Siberian__   -2    k   loss
Central Arctic_   -8    k   loss
         
Kara_________    3    k   gain
Laptev_______    1    k   gain
Chukchi______   -2    k   loss
         
Other Seas         
Okhotsk______    16    k   gain
St Lawrence___    5    k   gain
Hudson Bay___    3    k   gain
Area gain 3 k, 28k less than the 2010's average for the day.

Other stuff

GFS indicates that overall the Arctic temperature anomaly remains between close to zero for the next 3 days and then rises to over +2 degrees in the following week. The highly variable +ve and -ve anomalies at various times over the various regions of the Arctic may become even more extreme. Hence sudden changes in gain and loss in peripheral seas (e.g. Bering, Okhotsk, Baffin, Greenland).

Also of note is that without the Okhotsk area gain of 16k there would be an area loss of 13k on this day (and the previous 3 days). (spotted first by Stephan ).
"Para a Causa do Povo a Luta Continua!"
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Stephan

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Re: 2019 sea ice area and extent data
« Reply #132 on: February 01, 2019, 10:41:02 PM »
If it were not for the Okhotsk Sea we would see a decline in Artic Sea Ice area the last four days...

Juan C. García

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Re: 2019 sea ice area and extent data
« Reply #133 on: February 02, 2019, 05:03:19 AM »
If it were not for the Okhotsk Sea we would see a decline in Artic Sea Ice area the last four days...

Well, two consecutive declines...

[ADS NIPR VISHOP (JAXA)] Arctic Sea Ice Extent.
 
February 1st, 2019:
     13,426,750 km2, a drop of -53,127 km2:o
     2019 is now the 4th lowest on record.
Which is the best answer to Sep-2012 ASI lost (compared to 1979-2000)?
50% [NSIDC Extent] or
73% [PIOMAS Volume]

Volume is harder to measure than extent, but 3-dimensional space is real, 2D's hide ~50% thickness gone.
-> IPCC/NSIDC trends [based on extent] underestimate the real speed of ASI lost.

gerontocrat

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Re: 2019 sea ice area and extent data
« Reply #134 on: February 02, 2019, 08:18:45 AM »
JAXA ARCTIC EXTENT 13,426,750 km2(February 1, 2019)

- Extent loss 53k, 79k less than average gain of 26 k on this day.
- Extent is 4th lowest in the satellite record,
- Freezing to date from minimum is 147 k (1.6%) less than the 10 year average extent gain,
- On average (last 10 years) 91.5 % of the increase in extent from min to max is done.
- On average (last 10 years) 38 days to maximum (11th March)

The Perils of Projections.
The outcome from using the 10 year average extent gain from now is a maximum extent of 14.19 million km2 (310k >2017's record low maximum). Using the last 5 years average extent gain gives a maximum for 14.05 million km2, (170k >2017). This is in contrast with using a polynomial trend line projection, which produces a max of around 13.6 million km2 on the 15th February.

Other Stuff
GFS indicates that overall the Arctic temperature anomaly remains between zero and +3 degrees over the next week. The highly variable +ve and -ve anomalies at various times over the various regions of the Arctic may become even more extreme. This may exaggerate the normal variations in daily change from gains to losses and back to gains that happens at this time of year.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

gerontocrat

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Re: 2019 sea ice area and extent data
« Reply #135 on: February 02, 2019, 02:19:47 PM »
NSIDC Total Area as at 1 February 2019 (5 day trailing average) 12,494,771   km2

         
Total Area         
 12,494,771    km2      
 250,738    km2   >    2010's average.
 481,128    k   >   2018
-282,849    k   <    2000's average.
         
Total Gain   -13    k   
Peripheral Seas   -20    k   loss
Central Seas__   -5    k   loss
Other Seas___    12    k   gain
         
Peripheral Seas         
Bering _______   -2    k   loss
Baffin  Bay____    3    k   gain
Greenland____   -3    k   loss
Barents ______   -19    k   loss
         
CAB Seas         
Beaufort_____    2    k   gain
CAA_________    0    k   gain
East Siberian__   -3    k   loss
Central Arctic_   -6    k   loss
         
Kara_________    2    k   gain
Laptev_______    0    k   gain
Chukchi______   -1    k   loss
         
Other Seas         
Okhotsk______    3    k   gain
St Lawrence___    7    k   gain
Hudson Bay___    2    k   gain
Area LOSS 13 k, 48k less than the 2010's average gain of 35k on this day.

Other stuff

GFS indicates that overall the Arctic temperature anomaly remains between zero and +3 degrees over the next week. The highly variable +ve and -ve anomalies at various times over the various regions of the Arctic may become even more extreme. This may exaggerate the normal variations in daily change from gains to losses and back to gains that happens at this time of year.Hence sudden changes in gain and loss in peripheral seas (e.g.s Bering, Okhotsk, Baffin, Greenland , Barents).

In the last 2 days it is the Barents that is losing area rapidly.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

Juan C. García

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Re: 2019 sea ice area and extent data
« Reply #136 on: February 03, 2019, 05:00:28 AM »
[ADS NIPR VISHOP (JAXA)] Arctic Sea Ice Extent.
 
February 2nd, 2019:
     13,447,260 km2, an increase of 20,510 km2.
     2019 is the 4th lowest on record.
Which is the best answer to Sep-2012 ASI lost (compared to 1979-2000)?
50% [NSIDC Extent] or
73% [PIOMAS Volume]

Volume is harder to measure than extent, but 3-dimensional space is real, 2D's hide ~50% thickness gone.
-> IPCC/NSIDC trends [based on extent] underestimate the real speed of ASI lost.

gerontocrat

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Re: 2019 sea ice area and extent data
« Reply #137 on: February 03, 2019, 05:14:12 AM »
JAXA ARCTIC EXTENT 13,447,260 km2(February 2, 2019)

- Extent gain 21k, 18k less than average gain of 39 k on this day.
- Extent is 4th lowest in the satellite record,
- Freezing to date from minimum is 165 k (1.8%) less than the 10 year average extent gain,
- On average (last 10 years) 91.9 % of the increase in extent from min to max is done.
- On average (last 10 years) 37 days to maximum (11th March)

The Perils of Projections.
The outcome from using the 10 year average extent gain from now is a maximum extent of 14.17 million km2 (390k >2017's record low maximum). Using the last 5 years average extent gain gives a maximum for 14.03 million km2, (170k >2017). This is in contrast with using a polynomial trend line projection, which produces a max of around 13.6 million km2 on the 15th February.

Other Stuff
GFS indicates that overall the Arctic temperature anomaly remains between +1 and +3 degrees over the next week. The highly variable +ve and -ve anomalies at various times over the various regions of the Arctic may remain extreme. This may exaggerate the normal variations in daily change in the peripheral seas from gains to losses and back to gains that happens at this time of year.
[/quote]
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

gerontocrat

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Re: 2019 sea ice area and extent data
« Reply #138 on: February 03, 2019, 02:16:36 PM »
NSIDC Total Area as at 2 February 2019 (5 day trailing average) 12,466,241   km2
         
Total Area         
 12,466,241    km2      
 180,180    km2   >    2010's average.
 367,241    k   >   2018
-334,004    k   <    2000's average.
         
Total Gain   -29    k   
Peripheral Seas   -28    k   loss
Central Seas__    1    k   gain
Other Seas___   -2    k   loss
         
Peripheral Seas         
Bering _______   -7    k   loss
Baffin  Bay____   -1    k   loss
Greenland____   -4    k   loss
Barents ______   -16    k   loss
         
CAB Seas         
Beaufort_____    4    k   gain
CAA_________    1    k   gain
East Siberian__   -2    k   loss
Central Arctic_   -3    k   loss
         
Kara_________    1    k   gain
Laptev_______   -1    k   loss
Chukchi______    0    k   gain
         
Other Seas         
Okhotsk______   -7    k   loss
St Lawrence___    6    k   gain
Hudson Bay___   -1    k   loss
Area LOSS 29 k, 71k less than the 2010's average gain of 42k on this day.

Other stuff

GFS indicates that overall the Arctic temperature anomaly remains between +1 and +3 degrees over the next week. The highly variable +ve and -ve anomalies at various times over the various regions of the Arctic may become even more extreme. This may exaggerate the normal variations in daily change from gains to losses and back to gains that happens at this time of year.Hence sudden changes in gain and loss in peripheral seas (e.g.s Bering, Okhotsk, Baffin, Greenland , Barents).

As you can see from the last table, all the peripheral seas lost area on this day.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

Juan C. García

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Re: 2019 sea ice area and extent data
« Reply #139 on: February 04, 2019, 05:09:12 AM »
More data, SAT for January. Second lowest Arctic-wide for the last 15 years, all sectors down compared to last three years:
Extend is not showing the increase that it should have after the cold January.
It is 4th lowest and it could be 3rd lowest in a couple of days.

[ADS NIPR VISHOP (JAXA)] Arctic Sea Ice Extent.
 
February 3rd, 2019:
     13,428,392 km2, a drop of -18,868 km2.
     2019 is the 4th lowest on record.
PS: 2010 has not official value. Average used.
Which is the best answer to Sep-2012 ASI lost (compared to 1979-2000)?
50% [NSIDC Extent] or
73% [PIOMAS Volume]

Volume is harder to measure than extent, but 3-dimensional space is real, 2D's hide ~50% thickness gone.
-> IPCC/NSIDC trends [based on extent] underestimate the real speed of ASI lost.

jdallen

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Re: 2019 sea ice area and extent data
« Reply #140 on: February 04, 2019, 08:09:07 AM »
More data, SAT for January. Second lowest Arctic-wide for the last 15 years, all sectors down compared to last three years:
Extend is not showing the increase that it should have after the cold January.
It is 4th lowest and it could be 3rd lowest in a couple of days.

[ADS NIPR VISHOP (JAXA)] Arctic Sea Ice Extent.
 
February 3rd, 2019:
     13,428,392 km2, a drop of -18,868 km2.
     2019 is the 4th lowest on record.
PS: 2010 has not official value. Average used.
Here is a relevant question; has extent dropped previously when the overall extent was so low and at the peak of the season?
This space for Rent.

gerontocrat

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Re: 2019 sea ice area and extent data
« Reply #141 on: February 04, 2019, 09:02:21 AM »
JAXA ARCTIC EXTENT 13,428,392 km2(February 3, 2019)

- Extent loss 19k, 49k less than average gain of 30 k on this day.
- Extent is 4th lowest in the satellite record,
- Freezing to date from minimum is 214 k (2.3%) less than the 10 year average extent gain,
- On average (last 10 years) 92.2 % of the increase in extent from min to max is done.
- On average (last 10 years) 36 days to maximum (11th March)

The Perils of Projections.
The outcome from using the 10 year average extent gain from now is a maximum extent of 14.12 million km2 (240k >2017's record low maximum). Using the last 5 years average extent gain gives a maximum for 13.99 million km2, (110k >2017). This is in contrast with using a polynomial trend line projection, which produces a max of around 13.55 million km2 on the 10th February - now that would be a surprise.

Other Stuff
GFS indicates that overall the Arctic temperature anomaly remains between +1 and +3 degrees over the next week or so. The highly variable +ve and -ve anomalies at various times over the various regions of the Arctic may remain extreme. This may exaggerate the normal variations in daily change in the peripheral seas from gains to losses and back to gains that happens at this time of year.

In my not very humble opinion a very cold January Arctic-wide can be somewhat irrelevant as far as extent is concerned, as the main Arctic seas are pretty much frozen up by end January in every year. What matters is temperatures, winds and ocean currents at the periphery, especially the Pacific gateway, the Atlantic Front and Baffin Bay. This determines ice gain and loss in these peripheral seas that determine the final outcome of maximum for the year.
"Para a Causa do Povo a Luta Continua!"
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"Damn, I wanted to see what happened next" (Epitaph)

oren

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Re: 2019 sea ice area and extent data
« Reply #142 on: February 04, 2019, 09:29:59 AM »
Here is a relevant question; has extent dropped previously when the overall extent was so low and at the peak of the season?
Yes. It is possible to see in JCG's chart several similar drops around this time of year.

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Re: 2019 sea ice area and extent data
« Reply #143 on: February 04, 2019, 10:35:36 AM »
Here is a relevant question; has extent dropped previously when the overall extent was so low and at the peak of the season?
Yes. It is possible to see in JCG's chart several similar drops around this time of year.
The drop in the last 5 days is some 70.000 km2, while 2016 dropped 150.000 km2 in four days starting on the 2nd of February.

gerontocrat

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Re: 2019 sea ice area and extent data
« Reply #144 on: February 04, 2019, 01:24:49 PM »
Here is a relevant question; has extent dropped previously when the overall extent was so low and at the peak of the season?
Yes. It is possible to see in JCG's chart several similar drops around this time of year.
The drop in the last 5 days is some 70.000 km2, while 2016 dropped 150.000 km2 in four days starting on the 2nd of February.
I think we only notice these variations at this time of year because they are above and below zero.   In any year there are several days or even weeks of daily change of similar or greater amounts above or below the average .

ps: I am looking forward to March when Neven has to decide when to open the 2019 melting thread, and is bombarded with unwanted advice and demands from all sides as daily extent change wobbles around above and below zero.
« Last Edit: February 04, 2019, 01:33:44 PM by gerontocrat »
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gerontocrat

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Re: 2019 sea ice area and extent data
« Reply #145 on: February 04, 2019, 02:04:20 PM »
NSIDC Total Area as at 3 February 2019 (5 day trailing average) 12,431,931   km2
         
Total Area         
 12,431,931    km2      
 102,041    km2   >    2010's average.
 232,412    k   >   2018
-387,353    k   <    2000's average.
         
Total Gain   -34    k   
Peripheral Seas   -26    k   loss
Central Seas__   -3    k   loss
Other Seas___   -5    k   loss
         
Peripheral Seas         
Bering _______   -12    k   loss
Baffin  Bay____   -3    k   loss
Greenland____   -3    k   loss
Barents ______   -7    k   loss
         
CAB Seas         
Beaufort_____    2    k   gain
CAA_________    1    k   gain
East Siberian__   -0    k   loss
Central Arctic_   -8    k   loss
         
Kara_________    1    k   gain
Laptev_______   -1    k   loss
Chukchi______   -0    k   loss
         
Other Seas         
Okhotsk______   -10    k   loss
St Lawrence___    7    k   gain
Hudson Bay___   -2    k   loss
Area LOSS 34 k, 78k less than the 2010's average gain of 44k on this day.

Other stuff

GFS indicates that overall the Arctic temperature anomaly remains between +1 and +3 degrees over the next week or so. The highly variable +ve and -ve anomalies at various times over the various regions of the Arctic may remain extreme.

In my not very humble opinion a very cold January Arctic-wide can be somewhat irrelevant as far as the final resulting maximum is concerned, as the main Arctic seas are pretty much frozen up by end January in every year. What matters is temperatures, winds and ocean currents at the periphery, especially the Pacific gateway, the Atlantic Front and Baffin Bay. This determines ice gain and loss in these peripheral seas that determine the final outcome of maximum for the year.
As you can see from the last table, all the peripheral seas lost area on this day (and the day before).

ps: The very cold January does seem to have bumped up sea ice thickness - presumably this could / will affect the speed of extent and area losses later in the melting season.
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uniquorn

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Re: 2019 sea ice area and extent data
« Reply #146 on: February 04, 2019, 02:24:40 PM »
Quote
ps: The very cold January does seem to have bumped up sea ice thickness
Yes, should help a bit.

Dharma Rupa

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Re: 2019 sea ice area and extent data
« Reply #147 on: February 04, 2019, 03:10:09 PM »
ps: I am looking forward to March when Neven has to decide when to open the 2019 melting thread, and is bombarded with unwanted advice and demands from all sides as daily extent change wobbles around above and below zero.

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Re: 2019 sea ice area and extent data
« Reply #148 on: February 04, 2019, 03:28:17 PM »
ps: I am looking forward to March when Neven has to decide when to open the 2019 melting thread, and is bombarded with unwanted advice and demands from all sides as daily extent change wobbles around above and below zero.

Yes, that's my favourite time of year!  ;D
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jdallen

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Re: 2019 sea ice area and extent data
« Reply #149 on: February 04, 2019, 05:38:31 PM »
Here is a relevant question; has extent dropped previously when the overall extent was so low and at the peak of the season?
Yes. It is possible to see in JCG's chart several similar drops around this time of year.
The drop in the last 5 days is some 70.000 km2, while 2016 dropped 150.000 km2 in four days starting on the 2nd of February.
I think we only notice these variations at this time of year because they are above and below zero.   In any year there are several days or even weeks of daily change of similar or greater amounts above or below the average .

ps: I am looking forward to March when Neven has to decide when to open the 2019 melting thread, and is bombarded with unwanted advice and demands from all sides as daily extent change wobbles around above and below zero.
Serves me right for trying to reply on my phone instead of sitting down where I can type.

My curiosity is more nuanced than just drops at this time of year.  I'm also reflecting on the size of the pack when the drop occurs.  That we've had similar drops at this time of year is no surprise to me.  I'm wondering, going back, what similar events we've had at similar levels of coverage.

So, there is a timing issue, but it has more to do with when the pack has passed the current threshold in the past, and what sort of volatility it had at those junctures. 

What's sticking in my head are questions actually more oriented towards ice quality and total heat content, which are probably unanswerable with the instrumentation currently available.
This space for Rent.