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What will NSIDC 2020 Arctic SIE September average be?

Above 5.25 million km^2
0 (0%)
Between 4.75 and 5.25 million km^2
0 (0%)
Between 4.50 and 5.00 million km^2
0 (0%)
Between 4.25 and 4.75 million km^2
1 (1.6%)
Between 4.00 and 4.50 million km^2
10 (16.1%)
Between 3.75 and 4.25 million km^2
12 (19.4%)
Between 3.50 and 4.00 million km^2
17 (27.4%)
Between 3.25 and 3.75 million km^2
11 (17.7%)
Between 3.00 and 3.50 million km^2
8 (12.9%)
Between 2.75 and 3.25 million km^2
1 (1.6%)
Between 2.50 and 3.00 million km^2
0 (0%)
Between 2.25 and 2.75 million km^2
1 (1.6%)
Between 2.00 and 2.50 million km^2
1 (1.6%)
Under 2.00 million km^2
0 (0%)

Total Members Voted: 59

Voting closed: August 11, 2020, 04:06:40 AM

Author Topic: NSIDC 2020 Arctic SIE September average: August poll  (Read 2535 times)

Juan C. García

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NSIDC 2020 Arctic SIE September average: August poll
« on: July 31, 2020, 04:06:40 AM »
ATTENTION: There are two ASI extent polls on the ASIF. This one is for NSIDC sea ice extent monthly minimum or September average (which is also used for the SIPN sea ice outlook), the other is for JAXA sea ice extent daily minimum [provided by JAXA (ADS-NIPR-VISHOP)].
Make sure you are aware of the difference before voting.

These are the September averages on 2000-2019 (in millions km2):

   Year          Extent
                10^6 km2
1980's Avg.   7.21
1990's Avg.   6.66
2000's Avg.   5.65
2010's Avg.   4.68
2000             6.25
2001             6.73
2002             5.83
2003             6.12
2004             5.98
2005             5.50
2006             5.86
2007             4.27
2008             4.69
2009             5.26
2010             4.87
2011             4.56
2012             3.57
2013             5.21
2014             5.22
2015             4.62
2016             4.53
2017             4.82
2018             4.71
2019             4.32

From lowest to highest:
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: NSIDC 2020 Arctic SIE September average: August poll
« Reply #1 on: July 31, 2020, 06:29:51 AM »
For today, my bet is between 3.75 and 4.25 million km^2.
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.

oren

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Re: NSIDC 2020 Arctic SIE September average: August poll
« Reply #2 on: July 31, 2020, 07:17:30 AM »
Dropped one bin to 3.50-4.00. This is the hardest achieve of all my predictions, upside risk much higher than downside risk.

icefisher

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Re: NSIDC 2020 Arctic SIE September average: August poll
« Reply #3 on: July 31, 2020, 09:49:39 PM »
+1 Juan.  My range is 4.22+/- .18.  Probably 2nd but 3rd also possible.

Stephan

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Re: NSIDC 2020 Arctic SIE September average: August poll
« Reply #4 on: August 01, 2020, 10:40:03 PM »
I repeated my guesses from June and July with the bin centered at 4.25 M km².
It is too late just to be concerned about Climate Change

gerontocrat

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Re: NSIDC 2020 Arctic SIE September average: August poll
« Reply #5 on: August 02, 2020, 08:26:41 PM »
Some data to help confuse the issue.

Despite the last 7 days extent losses being way below average, the July 2020 Monthly Average Extent is a record low 7.50 million km2, some 304k less than July 2019, which itself was a record low.

7.500 million km2 is 437k less than the value from the linear trend, which is a reduction of 70k per annum. i.e. July 2020 is more than 6 years less than that linear trend.

IF remaining extent losses to minimum turn ou to be at the average of the last 10 years remaining melt, the September Monthly Average would be 3.96 million km2, 412k above the record low of 3.55 million km2 in 2012, but 317k less than the 2007 (2nd lowest) value.

3.96 million km2 is 412k less than the value from the linear trend, which is a reduction of 83k per annum. i.e. July 2020 is about years less than the value from the linear trend.

i.e. Average extent loss from now puts the September monthly average pretty much slap in the mid-point of 2012 (lowest) and 2007 (2nd lowest).

Like all projections / predictions / forecasts there is only one certainty. It won't happen that way, and even that is uncertain.

I'm waiting for PIOMAS volume, a few days more data and Mystic Meg before I cast my vote.
"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: NSIDC 2020 Arctic SIE September average: August poll
« Reply #6 on: August 02, 2020, 10:53:24 PM »
For today, my bet is between 3.75 and 4.25 million km^2.

IF remaining extent losses to minimum turn ou to be at the average of the last 10 years remaining melt, the September Monthly Average would be 3.96 million km2, 412k above the record low of 3.55 million km2 in 2012, but 317k less than the 2007 (2nd lowest) value.

Like all projections / predictions / forecasts there is only one certainty. It won't happen that way, and even that is uncertain.

I'm waiting for PIOMAS volume, a few days more data and Mystic Meg before I cast my vote.

So, my prediction is in corcondancia with your numbers, for now.
I am also waiting for PIOMAS and also, to see how much extent/area ASI melting we will have in the following 7 days.
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: NSIDC 2020 Arctic SIE September average: August poll
« Reply #7 on: August 09, 2020, 05:50:01 AM »
Just 2 more days to vote or change your vote.  ;)
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: NSIDC 2020 Arctic SIE September average: August poll
« Reply #8 on: August 10, 2020, 06:00:25 AM »
I am going up one bin, to 4.0-4.5 M km2.
There is only one day left to vote or change your vote.
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.

glennbuck

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Re: NSIDC 2020 Arctic SIE September average: August poll
« Reply #9 on: August 10, 2020, 09:15:02 AM »
3.0 m km2- 3.5 m km2

slow wing

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Re: NSIDC 2020 Arctic SIE September average: August poll
« Reply #10 on: August 10, 2020, 02:45:23 PM »
Dropping down half a bin as the high stayed high & the sun kept shining, & then the wind blew in the Beaufort.

August poll for NSIDC: 3.75-4.25M km2 VHC (Very high confidence)

 I always estimate (guess) the JAXA daily minimum then add 0.5M km2 to predict the NSIDC.

The Walrus

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Re: NSIDC 2020 Arctic SIE September average: August poll
« Reply #11 on: August 10, 2020, 06:41:18 PM »
I am going up one bin, to 4.0-4.5 M km2.
There is only one day left to vote or change your vote.

Doing the same.  The recent melt slowdown cause me to rethink the final position. 

Juan C. García

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Re: NSIDC 2020 Arctic SIE September average: August poll
« Reply #12 on: August 20, 2020, 01:20:46 AM »
I am going up one bin, to 4.0-4.5 M km2.
There is only one day left to vote or change your vote.

Doing the same.  The recent melt slowdown cause me to rethink the final position.

The middle of our bet is right on what NSIDC is forecasting.
I am not sure is that is good or bad!  ;)

NSIDC has done a mid-August update. https://nsidc.org/arcticseaicenews/

It includes a projection of the 2020 minimum extent - tends to just above 4 million km2.

Given JAXA data tends to be a bit lower, it corresponds well to a projection for JAXA extent of a bit under 4 million km2.
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.

igs

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Re: NSIDC 2020 Arctic SIE September average: August poll
« Reply #13 on: August 20, 2020, 06:51:40 PM »
All know and frequently cited algorithms will fail by a huge margin this year.


This si one of situations where machines don't come even close to the human brain and eye.


Stats and algorithms are useful and powerful tools but we humans have to recognize at which moments in time we have to take the helm exclusively.

Juan C. García

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Re: NSIDC 2020 Arctic SIE September average: August poll
« Reply #14 on: August 27, 2020, 04:32:15 PM »
This is NSIDC Chartic with data until August 26th, 2020.
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: NSIDC 2020 Arctic SIE September average: August poll
« Reply #15 on: September 01, 2020, 12:22:01 PM »
Quote
Sea Ice Outlook: 2020 August Report
31 August 2020

The August Outlook is based on a total of 39 forecasts (Figure 1), of which 25 are new August submissions while the remaining 14 are carried over from June and July. The median August Outlook value for the September 2020 sea-ice extent is 4.30 million square kilometers, with quartile values of 4.1 and 4.5 million square kilometers. Of the 39 August 2020 contributions, 16 are based on dynamical models, 17 are based on statistical methods, 4 are based on heuristic approaches (qualitative analyses), and 2 used machine learning-based methods. The median of the August submissions is close to that from July (4.36 million square kilometers) and June (4.33 million square kilometers). The 2020 August Outlook median is higher than 2019 (4.22 million square kilometers) and lower than 2018 (4.57 million square kilometers).
https://www.arcus.org/sipn/sea-ice-outlook/2020/august
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: NSIDC 2020 Arctic SIE September average: August poll
« Reply #16 on: September 09, 2020, 04:27:01 PM »
September 8th NSIDC 5-day trailing average at 3.8M km2.
It looks that is sure that 2020 September average will be 2nd lowest, on the range 3.75-4.25M km2. Not sure if it will be above or under the 4M km2.
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: NSIDC 2020 Arctic SIE September average: August poll
« Reply #17 on: September 09, 2020, 05:42:45 PM »
Juan's post reminded me to have another look at that.

The Plume attached shows how the September monthly average most likely depends on the speed of extent gain in mid-late September. You can see from the plume that this varies greatly - from a very fast refreeze in 2016, compared with in 2018 a further significant extent loss and a very slow refreeze.

Hoever, if further extent loss and then extent gain is at the average for the rest of September, the monthly average will be just under 3.9 million km2, close on 0.5 million km2 or 5+ years ahead of the linear trend.
"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)