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gerontocrat

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Re: 2020 Sea ice area and extent data
« Reply #2050 on: January 01, 2021, 01:49:27 PM »
JAXA Data - a bit more

Despite the extreme sea ice extent recovery in late October early November, extent ended the year at 3rd lowest in the 42 year satellite record.

The December monthly average, at 11.24 million km2, is 2nd lowest in the satellite record, almost exactly at the trend value. This is 0.24 million km2 more than the record low of Dec 2016 and 0.18 million km2 less than Dec 2019.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
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NevB

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Re: 2020 Sea ice area and extent data
« Reply #2051 on: January 01, 2021, 03:13:30 PM »
Just a quick note, to deeply thank Juan and Gerontocrat for your daily updates.
I'm sure there is a lot of us coming here every day to check. Truly thanks.

A serene and healthy New Year to everybody!

+1 I also would like to thank you both for putting your time into this.

Pagophilus

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Re: 2020 Sea ice area and extent data
« Reply #2052 on: January 01, 2021, 04:41:56 PM »
Just a quick note, to deeply thank Juan and Gerontocrat for your daily updates.
I'm sure there is a lot of us coming here every day to check. Truly thanks.

A serene and healthy New Year to everybody!

+1 I also would like to thank you both for putting your time into this.
My thanks also.  And a happy and healthy 2021 to you all.

Shared Humanity

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Re: 2020 Sea ice area and extent data
« Reply #2053 on: January 01, 2021, 04:51:18 PM »
We all have certain routines in our lives. One of my morning routines is to visit this Sea Ice Area and Extent Data thread. Thank you for all that you do for this community. May we all have a much better year then the sucky one we just finished.

gerontocrat

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Re: 2020 Sea ice area and extent data
« Reply #2054 on: January 01, 2021, 04:55:28 PM »
NSIDC Total AREA as at 31-Dec-2020 (5 day trailing average) 11,031,837 KM2         
         
Total Area         
 11,031,837    km2      
-162,333    km2   <   2010's average.
-382,664    km2   <   2019
-580,700    km2   <   2000's average.
         
Total Change    18    k   gain
Peripheral Seas    3    k   gain
Central Seas___    15    k   gain
         
Peripheral Seas         
Okhotsk______    9    k   gain
Bering _______   -4    k   loss
Hudson Bay___   -3    k   loss
Baffin  Bay____   -6    k   loss
St Lawrence___   -2    k   loss
Greenland____    9    k   gain
Barents ______   -0    k   loss
         
Central Arctic  Ocean Seas         
Chukchi______   -2    k   loss
Beaufort_____    1    k   gain
CAA_________   -0    k   loss
East Siberian__    2    k   gain
Central Arctic_    6    k   gain
Laptev_______   -1    k   loss
Kara_________    8    k   gain
         
Sea ice area gain on this day 18 k, 38 k less than the 2010's average gain of 56 k         
         
- 2020 area is at position #3 in the satellite record.         
- 2020 Area is 162 k less than the 2010's average         
- 2020 Area is 581 k less than the 2000's average         
- 2020 Area is 444 k more than 2016         
- 2020 Area is 383 k less than 2019          
- 2020 Area is 138 k less than 2012         
___________________________________________         
NSIDC Total EXTENT as at 31-Dec-2020 (5 day trailing average) 12,522,694 KM2         
         
NSIDC Sea ice EXTENT gain on this day 28 k, 27 k less than the 2010's average gain of 55k         
         
- 2020 EXTENT is at position #5 in the satellite record.         
- 2020 EXTENT is 88 k less than the 2010's average         
- 2020 EXTENT is 538 k less than the 2000's average         
- 2020 EXTENT is 109 k more than 2016         
- 2020 EXTENT is 194 k less than 2019          
- 2020 EXTENT is 218 k less than 2012         
___________________________________________         
Note: Click an image for full-size         
"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: 2020 Sea ice area and extent data
« Reply #2055 on: January 01, 2021, 06:23:03 PM »
NSIDC EXTENT Data - some more

The December monthly average at 11.49 million km2 is 2nd lowest in the satellite record, and just 55k below the trend value for Dec 20.

The 365 Day Trailing Average could be at a record low by Spring '21.
"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: 2020 Sea ice area and extent data
« Reply #2056 on: January 01, 2021, 06:28:22 PM »
NSIDC AREA Data - some more

The December monthly average at 9.97 million km2 is 2nd lowest in the satellite record, and at 187k below the trend value for Dec 20 is 4 years ahead of trend.

The 365 Day Trailing Average AREA could be at a record low by late '21. This is later than for EXTENT due to the spectacularly low area values throughout 2016 and into early 2017.
"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)

charles_oil

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Re: 2020 Sea ice area and extent data
« Reply #2057 on: January 01, 2021, 06:50:35 PM »
Plus another one +1 - a regular read for the updates - thanks for all you do. 


Happy New Year too.

Juan C. García

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Re: 2020 Sea ice area and extent data
« Reply #2058 on: January 02, 2021, 05:29:22 AM »
Hi!

We will continue in this new thread:

2021 Sea ice area and extent data
https://forum.arctic-sea-ice.net/index.php/topic,3370.0.html#new
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.

RikW

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Re: 2020 Sea ice area and extent data
« Reply #2059 on: January 02, 2021, 09:17:10 AM »
Yeah, a big thx from me too, it's one of my favorite forum topics on the internet because of the great daily updates :)

oren

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Re: 2020 Sea ice area and extent data
« Reply #2060 on: January 02, 2021, 11:14:50 AM »
Big thanks to Juan and Gero for their important daily contributions. 2020 is finally over...

gerontocrat

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Re: 2020 Sea ice area and extent data
« Reply #2061 on: January 03, 2021, 12:29:43 PM »
JAXA Data - a bit more on 2020

2020 had the lowest average daily sesa ice extent in the satellite record.

The simple daily average daily sea ice extent for the year was 9.674 million km2.
This was 42k less than in 2016, and 285k less than in 2012.

Put in another way, in 2020 there was on average 42k less ice and 42 k more open water for every day of the year than in any other 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)

kassy

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Re: 2020 Sea ice area and extent data
« Reply #2062 on: January 03, 2021, 04:36:04 PM »
Interesting data.

I take it that the three years cited above are the top 3. Could you add a table (or graph) of the other years?
Þetta minnismerki er til vitnis um að við vitum hvað er að gerast og hvað þarf að gera. Aðeins þú veist hvort við gerðum eitthvað.

gerontocrat

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Re: 2020 Sea ice area and extent data
« Reply #2063 on: January 03, 2021, 07:16:01 PM »
Interesting data.

I take it that the three years cited above are the top 3. Could you add a table (or graph) of the other years?
Is there some confusion here  ?
The graph above is not the 365 day trailing average.
It is the simple average of daily extent for each year.

Perhaps the attached column graph makes it more obvious.
"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)

kassy

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Re: 2020 Sea ice area and extent data
« Reply #2064 on: January 03, 2021, 11:59:05 PM »
No confusion but i called the years the top years because i was thinking about functional albedo loss which is the same as the bottom years for ext over the year so my bad.

Thanks for the graph.
Þetta minnismerki er til vitnis um að við vitum hvað er að gerast og hvað þarf að gera. Aðeins þú veist hvort við gerðum eitthvað.

Stephan

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Re: 2020 Sea ice area and extent data
« Reply #2065 on: January 10, 2021, 10:19:42 PM »
I added the monthly extent value for December 2020 into my long-term plot where I calculate the extent anomalies from 1979 up to now.
The average (1979-2020) December extent is now 12.66 M km². December 2020 had an average extent of 11.49 M km², which is 1.17 M km² less than that long-term average.
The rapid freeze-up in November and December reduced the anomaly we saw in October from the long-term linear trend line. The difference of the actual month from that trend line is -0.08 M km² (calculated from the linear trend line this December should have been at 11.57 M km²).
The slope of the long-term linear trend line has not changed since October (-0.0560).

See attached graph. Click to enlarge.
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