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What will the NSIDC 2019 Arctic SIE September average be?

Above 5.50 million km^2
0 (0%)
Between 5.00 and 5.50 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
5 (5.2%)
Between 4.25 and 4.75 million km^2
16 (16.7%)
Between 4.00 and 4.50 million km^2
19 (19.8%)
Between 3.75 and 4.25 million km^2
21 (21.9%)
Between 3.50 and 4.00 million km^2
12 (12.5%)
Between 3.25 and 3.75 million km^2
4 (4.2%)
Between 3.00 and 3.50 million km^2
8 (8.3%)
Between 2.75 and 3.25 million km^2
7 (7.3%)
Between 2.50 and 3.00 million km^2
2 (2.1%)
Between 2.25 and 2.75 million km^2
1 (1%)
Between 2.00 and 2.50 million km^2
1 (1%)
Under 2.00 million km^2
0 (0%)

Total Members Voted: 93

Voting closed: June 11, 2019, 09:45:19 PM

Author Topic: NSIDC 2019 Arctic SIE September average: June poll  (Read 2874 times)

Juan C. García

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NSIDC 2019 Arctic SIE September average: June poll
« on: May 31, 2019, 09:45:19 PM »
ATTENTION: There are two 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 2000-2018 (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

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 2019 Arctic SIE September average: June poll
« Reply #1 on: May 31, 2019, 09:47:12 PM »
I vote 4.00 to 4.50M 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.

Stephan

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Re: NSIDC 2019 Arctic SIE September average: June poll
« Reply #2 on: June 03, 2019, 07:16:14 PM »
Juan, I am with you again. Not knowing, which bin you voted for, I directly went into 4-4.5 Mio. km²
It is too late just to be concerned about Climate Change

jdallen

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Re: NSIDC 2019 Arctic SIE September average: June poll
« Reply #3 on: June 03, 2019, 08:21:17 PM »
I vote 4.00 to 4.50M km2.
I started there but decided to go one bucket lower.  I'm reasonably confident the end of season number  will be flirting with a break under 4.0.
This space for Rent.

Paddy

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Re: NSIDC 2019 Arctic SIE September average: June poll
« Reply #4 on: June 03, 2019, 09:41:14 PM »
 4.25 to 4.75.  Too often I've gone too low in my June prediction, and the forum as a whole has a strong tendency to do so, so I'm playing it cautious.
« Last Edit: June 03, 2019, 09:58:38 PM by Paddy »

DavidR

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Re: NSIDC 2019 Arctic SIE September average: June poll
« Reply #5 on: June 04, 2019, 04:02:32 PM »
3.75 to 4.25 (moved up one because this is the average)   Ice coverage looks a lot  like 2012 and 2016. Temperatures in the Arctic have been very  hot  over the past  two months. 

According to ESRL Air temps above 67N and 80N were hottest  on record for the last month and sea temps above 67N were also hottest on record.
https://www.esrl.noaa.gov/psd/cgi-bin/data/timeseries/timeseries1.pl

This suggests a lot of inbuilt  melting  as that heat attacks the ice.
« Last Edit: June 08, 2019, 05:08:44 PM by DavidR »
Toto, I've a feeling we're not in Kansas anymore

pearscot

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Re: NSIDC 2019 Arctic SIE September average: June poll
« Reply #6 on: June 04, 2019, 05:46:17 PM »
I voted 4-4.5 million. I have been wrong the last few years on the arctic and I don't see this year shaping up to be like 2012.
pls!

Brigantine

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Re: NSIDC 2019 Arctic SIE September average: June poll
« Reply #7 on: June 06, 2019, 08:02:42 AM »
Link to last year's same poll thread :)

UPDATE: Provisionally voted for 4.25 - 4.75, medium confidence. Won't be surprised if I end up revising this down in the next few days.
Based simply on taking my JAXA choice and adding a bin or two. Not very sophisticated.
« Last Edit: June 08, 2019, 12:52:20 PM by Brigantine »

oren

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Re: NSIDC 2019 Arctic SIE September average: June poll
« Reply #8 on: June 06, 2019, 08:57:24 AM »
I should have voted 4-4.5 but went one lower.
A lot depends on the date of refreeze, 2007 was very late and 2016 very early, hence their 0.25 difference.

diablobanquisa

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Re: NSIDC 2019 Arctic SIE September average: June poll
« Reply #9 on: June 08, 2019, 11:53:46 AM »
I voted between 3.75 and 4.25 million km^2. This year I am pessimistic: sunny start to the melt season with Highs and even a Dipole-like pattern,  low continental snow cover, Beaufort early opening, thickest ice pilled towards Fram...

It will depend on the weather during the next three months, but in my opinion it looks worse than in previous years (even if Cryosat spring thickness data were rather good).

Juan C. García

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Re: NSIDC 2019 Arctic SIE September average: June poll
« Reply #10 on: June 09, 2019, 10:18:42 PM »
Only two 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.

Juan C. García

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Re: NSIDC 2019 Arctic SIE September average: June poll
« Reply #11 on: June 10, 2019, 03:37:03 PM »
I vote 4.00 to 4.50M km2.
I am changing my vote to 3.75 to 4.25M 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.

Klondike Kat

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Re: NSIDC 2019 Arctic SIE September average: June poll
« Reply #12 on: June 10, 2019, 05:32:30 PM »
I am sticking with 4.5 - 5.0.  The melt over the past 45 days in lower than average, and I just do not see the melt increasing significantly to make up the difference. 

be cause

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Re: NSIDC 2019 Arctic SIE September average: June poll
« Reply #13 on: June 10, 2019, 05:37:58 PM »
at least Juan is moving in the right direction .. :) .. b.c.
2007 + 5 = 2012 + 4 = 2016 + 3 = 2019 ...

RoxTheGeologist

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Re: NSIDC 2019 Arctic SIE September average: June poll
« Reply #14 on: June 10, 2019, 06:21:55 PM »
I vote 4.00 to 4.50M km2.
I am changing my vote to 3.75 to 4.25M km2.

Juan, welcome to my bin.

Juan C. García

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Re: NSIDC 2019 Arctic SIE September average: June poll
« Reply #15 on: June 10, 2019, 08:10:45 PM »
I vote 4.00 to 4.50M km2.
I am changing my vote to 3.75 to 4.25M km2.

Juan, welcome to my bin.
This is going to be the right one…  ;)
Or not???

Come on guys, we need 100 votes at least!!!
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.

magnamentis

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Re: NSIDC 2019 Arctic SIE September average: June poll
« Reply #16 on: June 10, 2019, 08:16:20 PM »
this:

Stephan

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Re: NSIDC 2019 Arctic SIE September average: June poll
« Reply #17 on: June 10, 2019, 10:08:49 PM »

Come on guys, we need 100 votes at least!!!
At the moment, there are just 80 votes in the list.
It is too late just to be concerned about Climate Change

slow wing

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Re: NSIDC 2019 Arctic SIE September average: June poll
« Reply #18 on: June 11, 2019, 10:46:55 AM »
I voted "Between 4.00  and 4.50 million km^2" for the reasons given in the other poll thread.

Klondike Kat

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Re: NSIDC 2019 Arctic SIE September average: June poll
« Reply #19 on: June 11, 2019, 01:31:01 PM »

Come on guys, we need 100 votes at least!!!
At the moment, there are just 80 votes in the list.

The plea is working.  We are up to 90.

Juan C. García

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Re: NSIDC 2019 Arctic SIE September average: June poll
« Reply #20 on: June 11, 2019, 09:06:43 PM »

Come on guys, we need 100 votes at least!!!
At the moment, there are just 80 votes in the list.

The plea is working.  We are up to 90.
Only 40 min. left to vote.
95 votes...
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.

Steven

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Re: NSIDC 2019 Arctic SIE September average: June poll
« Reply #21 on: June 22, 2019, 11:21:21 AM »
The June 2019 SIPN report is out:
https://www.arcus.org/sipn/sea-ice-outlook/2019/june

Quote
The median June Outlook value for a September 2019 sea-ice extent is 4.40 million square kilometers with quartiles of 4.2 and 4.8 million square kilometers (Figure 1). Contributions are based on statistical (13 inputs), dynamical models (14 inputs), and heuristic methods (4 inputs). Projected extents are slightly lower compared with 2018 June outlook (4.6 million square kilometers), but are about the same as those in the 2017 June outlook (4.43 million square kilometers). The projections range from 3.06 to 5.90 million square kilometers, which is greater than the range in 2018. Only one projection is for a new record low (below the mark of 3.60 set in 2012), but two more projections are for a sea-ice minimum below 4 million square kilometers. The median value of the projected September sea-ice extent is right along the linear trend line.

Again, as in previous years, the spread in the dynamical models are larger compared with statistical models. Overall, the heuristic method has the lowest projected September sea-ice extent value with a median at 4.09 million square kilometers, and the dynamical models have the highest number with the median at 4.56 million square kilometers.



Steven

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Re: NSIDC 2019 Arctic SIE September average: June poll
« Reply #22 on: June 22, 2019, 11:57:53 AM »
Looking at some of the indivual predictions in the SIPN report (non-exhaustive list):


Zhang & Schweiger (Washington), dynamic: 4.07 +/- 0.4:
Quote
Driven by the NCEP CFS forecast atmospheric forcing, PIOMAS is used to predict the total September 2019 Arctic sea ice extent as well as ice thickness field and ice edge location, starting on June 1.


Schroeder et al (CPOM), statistical: 4.3 +/- 0.5:
Quote
This is a statistical prediction based on the correlation between the ice area covered by melt-ponds in May and ice extent in September. The melt pond area is derived from a simulation with the sea ice model CICE in which we incorporated a physically based melt-pond model


Kay et al (NCAR), heuristic: 4.38 +/- 0.4:
Quote
An informal pool of 29 climate scientists in early June 2019 estimates that the September 2019 ice extent will be 4.38 million sq. km. (stddev. 0.40, min. 3.14, max. 5.03).


Nico Sun (Tealight), statistical: 4.4 (range 3.73-4.88):
Quote
uses incoming solar radiation and sea ice albedo derived from a predicted Sea Ice Concentration (SIC) value to calculate daily thickness losses for every NSIDC 25km grid cell. The initial thickness is calculated from AMSR2 sea ice volume and NSIDC SIC data.


NSIDC group, heuristic:  4.4 +/- 0.33:
Quote
This estimate is based on polling NSIDC employees for their estimates of the September extent. The submitted group estimate is the average of 10 individual contributions


Maslowski et al, dynamic: 4.91 +/- 0.30 (range 4.17-5.38):
Quote
We used RASM2_1_00, which is a recent version of the limited-area, fully coupled climate model


Kauker et al (AWI), dynamic: 5.18 +/-0.22:
Quote
For the present outlook the coupled sea ice-ocean model NAOSIM has been forced with atmospheric surface data from January 1948 to June 6th 2019

etc...

gerontocrat

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Re: NSIDC 2019 Arctic SIE September average: June poll
« Reply #23 on: June 22, 2019, 12:29:51 PM »
June 2019 SIPN report is out:
https://www.arcus.org/sipn/sea-ice-outlook/2019/june

Tealight (Nico Sun) has been very busy. Look for "Sun" in the tables and and images in the report.

Extract from his submission on SIE September Monthly Average.
Median 4.40
Ranges 3.73-4.88 Standard Deviations
His submission also tells you how he did it and the equations he used.

I wonder what Tealight has come up with so far for the JAXA daily extent minimum (and NSIDC and/or AMSR2 area).

Heuristic Estimates

The image from the report attached summarises the results by method, one of which is "heuristic" defined by Wikipedia as follows.
Quote
A heuristic technique (/hjʊəˈrɪstɪk/; Ancient Greek: εὑρίσκω, "find" or "discover"), often called simply a heuristic, is any approach to problem solving or self-discovery that employs a practical method, not guaranteed to be optimal, perfect, logical, or rational, but instead sufficient for reaching an immediate goal. Where finding an optimal solution is impossible or impractical, heuristic methods can be used to speed up the process of finding a satisfactory solution.

Heuristics can be mental shortcuts that ease the cognitive load of making a decision. Examples that employ heuristics include using a rule of thumb, an educated guess, an intuitive judgment, a guesstimate, profiling, or common sense.

Extract from a heuristic submission. I think the guy who did it is a hero for what he does. All credit to him for chucking in his submission.

"Executive summary" of your Outlook contribution (using 300 words or less) describe how and why your contribution was formulated. To the extent possible, use non-technical language.

email rec'd 11:00 pm (AKDT) on12 June: Hi Betsy, Well we just got back from the historic last
C-130H mission from USCG Air Station Kodiak. The long serving Hs are being replaces by the
C-130J model. Our Seasonal Ice Zone Reconnaissance Survey (SIZRS) flight was successful.
We flew up 150°W making oceanographic stations with expendable probes every degree fro 72
to 76 and then flew back at higher altitude doing atmospheric dropsonde drops. Notable ice
observations are that the ice edge has already retreated to 72°N and there was a lot of open water even up to 76°. The snow is already gone.

I usually try to do a little more analysis of trends for the year around the Arctic Ocean and look at the AO, but no time for that; it’s already midnight Pacific Daylight Time. To be any later and still be on the 12th, I’d have to be in Hawaii. So after exhausting if not exhaustive deliberation with my SIZRS colleges over pizza at the last eatery still open Kodiak, and considering the ice we saw today, my fresh from looking out the window is 3.8 million square km average Sept 2019 ice extent. Method would be politely called heuristic, and as ever the outlook recognizes that this summer's weather trumps everything else and is for the most part unknowable.

Best regards, Jamie
______________________________________________________________
Marvellous. So from now on, when someone asks me how on earth I come to and/or justify a result or comment my answer will be "using heuristic techniques when examination of the various data sources". Sounds much better than "dunno, sorta guess".
_______________________________________________________
"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)

Sterks

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Re: NSIDC 2019 Arctic SIE September average: June poll
« Reply #24 on: June 22, 2019, 01:11:56 PM »
Thanks for the heads up and that highlight Gero.
I find that including those heuristics models in the same pool may be an error.
I don't know also what the Hell is going on with those models predicting over five and even almost 6 mill Km2. WTF
And I miss Dekker's model (think I didnt see Slater model either)
« Last Edit: June 22, 2019, 01:27:06 PM by Sterks »

Richard Rathbone

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Re: NSIDC 2019 Arctic SIE September average: June poll
« Reply #25 on: June 22, 2019, 04:25:01 PM »
And I miss Dekker's model (think I didnt see Slater model either)

The NSIDC Horvath et al submission uses a similar method to Slater and might well be derived from it. Its not that good at this time of year (they give 3.66 - 7.97 as their 95% credible interval), its the August submission that it really works well for.