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Richard Rathbone

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September predictions challenge 2020
« on: June 02, 2020, 01:18:43 PM »
This is a challenge which accumulates scores across all the monthly polls on September sea ice to come up with an overall rating of how good the predictions made are. In addition to making a prediction, entrants are required to rate their confidence in that prediction. The higher the confidence, the narrower the margin of error you are allowed, but the higher score you get if the September ice ends up where you predicted it (and the bigger penalty you take if you miss).

The scoring is intended to reward having a good idea of the margin of error in your prediction. You score low if you understate your accuracy, and get penalised heavily if you are overconfident.

Polls included are: JAXA daily minimum extent, NSIDC September average extent.
Others may be added if they fit the structure of the challenge.

Quote
Points are scored as follows:
Very High Confidence: 10 points if you pick the correct bin, -10 points for all other bins.
High Confidence: 6 points for the correct bin, 2 points if one bin out, -2 points if two bins out, -6 points for all other bins
Medium Confidence: 4 points for the correct bin, 2 points if one bin out, 1 point if two bins out, -1 if three bins out, -2 if four bins out, -4 points for all other bins
Low Confidence: 2 points for the correct bin, 1 point if within 3 bins, -1 point if 4-6 bins out, -2 points for all other bins
Very Low Confidence: 1 point if in the correct bin, no score (or penalty) for any other bin.

This is for a poll structure with overlapping 0.5 bins. When the result (or the prediction) is outside the range covered by a poll with overlapping 0.5 bins, points will be awarded by counting each extra 0.25 beyond the poll range as 1 bin. Under 2.0 is not a valid prediction for this challenge, but 0.5-1.0 is and counts as 6 bins below the 2.0-2.5 bin.

To enter, post prediction and confidence in this thread before the closing date of the poll. The deadline is midnight UK time on the day the poll closes.
Editing to change a prediction is allowed at any time before the deadline. Editing for any reason after the deadline will result in disqualification of that entry.
In order to help keep track of entries, please quote your previous entry when making entries in subsequent months.

Currently active polls are:
June poll for JAXA minimum. https://forum.arctic-sea-ice.net/index.php/topic,3109.0.html
June poll for NSIDC September average. https://forum.arctic-sea-ice.net/index.php/topic,3110.0.html

There is no requirement to enter for all polls or to match your choice in the predictions thread.

A challenge entry should look something like this

Quote
June JAXA : 0.0-0.5, VH
June NSIDC: 6.0-6.5, M

The mother of all GACs expels all ice from the arctic on Sept 1st but is met by a UN aerosol barrage that leads to massive refreeze by Sept 30th.

The 2018 challenge thread. https://forum.arctic-sea-ice.net/index.php/topic,2327.0.html
The 2019 thread. https://forum.arctic-sea-ice.net/index.php/topic,2749.0.html

Juan C. García

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Re: September predictions challenge 2020
« Reply #1 on: June 02, 2020, 04:08:38 PM »
Thank you for posting the Challenge, Richard!  :)

I will start with:

June JAXA: 3.50-4.00M km2 LC (low confidence)
June NSIDC: 4.00-4.50M km2 LC (low confidence)

As Gerontocrat put it, I should be a bin up on JAXA, at least. But the climate tendency is to have lower values. The ASI has been lucky on 2015-2019. A lot of bad starts that at the end, they were not that bad. So this year we are starting on the lower side again. Sooner or later, we will have a bad year on September.

On NSIDC, I see that 2007 started to refreeze very late. If that doesn't happen, my bet is that there is 0.5M km2 difference between JAXA daily value and NSIDC monthly average. So having 2007 and 2019 in the middle, is a good bet for me.
« Last Edit: June 02, 2020, 04:21:57 PM by Juan C. García »
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.

blumenkraft

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Re: September predictions challenge 2020
« Reply #2 on: June 02, 2020, 04:16:21 PM »
JAXA:  3.25 - 3.75, high
NSIDC: 3.75 - 4.25, high

The Walrus

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Re: September predictions challenge 2020
« Reply #3 on: June 02, 2020, 05:19:13 PM »
JAXA:  3.75-4.25 (low)
NSIDC:  4.25-4.75 (high)

The JAXA daily low has much more variability, hence the lower confidence.  The NSIDC September average has been more tightly confined, with four of the past five years falling within this bin.  The exception was 2017 at 4.78, marginally above.  Only 2012 was lower, which now appears to be a true outlier.  Several other years were higher, but I am sticking with the trend towards lower averages.

oren

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Re: September predictions challenge 2020
« Reply #4 on: June 02, 2020, 07:44:17 PM »
JAXA: 3.5-4.0 (medium)
NSIDC: 4.0-4.5 (high)

Both bets one bin below the highest probability range, to take into account downward surprises.

Stephan

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Re: September predictions challenge 2020
« Reply #5 on: June 02, 2020, 09:15:41 PM »
I repeat the values I gave for the two polls:

JAXA Sep min. 3.75-4.25 M km² confidence high
NSIDC Sep ave. 4.00-4.50 M km² confidence high

I think the difference of ± 0.25 M km² around the average of each bin is large enough to state both values as being "highly confident".
It is too late just to be concerned about Climate Change

igs

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Re: September predictions challenge 2020
« Reply #6 on: June 02, 2020, 09:38:38 PM »
June JAXA    : 3.50-4.00M km2  LC 50%

June NSIDC' : 3.75-4.25M km2  LC 50%

PragmaticAntithesis

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Re: September predictions challenge 2020
« Reply #7 on: June 03, 2020, 02:16:51 AM »
June JAXA: 3.75-4.25 sqMm. Medium Confidence

June NSIDC: 4-4.5 sqMM. Medium Confidence
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Phoenix

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Re: September predictions challenge 2020
« Reply #8 on: June 04, 2020, 06:16:30 PM »
JAXA 4.10-4.60 hi
NSIDC 4.25-4.75 hi

Aluminium

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Re: September predictions challenge 2020
« Reply #9 on: June 08, 2020, 11:00:15 PM »
This year is hard for any predictions. However, in April two big bumblebees told me about strong melting season.

JAXA: 3.25-3.75, high.
NSIDC: 3.75-4.25 high.

Richard Rathbone

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Re: September predictions challenge 2020
« Reply #10 on: June 09, 2020, 08:39:13 PM »
Almost no method has any skill this far out, and I usually don't see the ones that do until the June SIPN report comes out towards the end of the month, so at this stage the trend is the pick.

JAXA: 3.75-4.25 M
NSIDC: 4.25-4.75 M
PIOMAS: 4.25-4.75 M

This is one of the occasional years when NSIDC rounds up and JAXA rounds down so my separation of them by 0.3 comes in 2 bins apart rather than 1 bin.

Challenge entries for these polls close at midnight on June 11, about 52 hours from now.
Entries for PIOMAS September average may also be made, to keep things simple the deadline is also midnight on June 11.

Phoenix

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Re: September predictions challenge 2020
« Reply #11 on: June 09, 2020, 09:00:17 PM »
JAXA 4.10-4.60 hi
NSIDC 4.25-4.75 hi
PIOMAS 4.5-5.0 hi
« Last Edit: June 09, 2020, 09:18:15 PM by Phoenix »

oren

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Re: September predictions challenge 2020
« Reply #12 on: June 09, 2020, 11:17:13 PM »
JAXA: 3.5-4.0 (medium)
NSIDC: 4.0-4.5 (high)

Both bets one bin below the highest probability range, to take into account downward surprises.
PIOMAS 4.25-4.75 High

Very little time left. I suggest anyone who voted and posted on the PIOMAS poll and doesn't post here in time gets an automatic entry of their vote at M confidence.

jdallen

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Re: September predictions challenge 2020
« Reply #13 on: June 10, 2020, 12:00:54 AM »
This is a big dice roll so early in the season, but I'll throw my hat in.

JAXA: 3.75-4.25     High
NSIDC: 4.0-4.5      High
PIOMAS: 3.75-4.25 Medium

I'm a little more aggressive in my guess than some, but I'm thinking we'll get some July and early August heat that will drive the number down.  Pretty sure we won't beat 2012. <whistles a bit n the scary dark>

If not, everything shifts up one box.

If we get weather that seriously hammers the ice during peak, all bets are off, and I'm probably too high.  Conditions are just that volatile that relatively modest swings in weather conditions can put us anywhere from 1st place to 5th.
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The Walrus

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Re: September predictions challenge 2020
« Reply #14 on: June 10, 2020, 12:04:00 AM »
Final guesses:

JAXA:   3.75-4.25  Low
NSIDC:   4.25-4.75  High
PIOMAS:  4.00-4.50  Medium

igs

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Re: September predictions challenge 2020
« Reply #15 on: June 10, 2020, 12:19:56 AM »
JAXA    : 3.50-4.00M km2  LC Medium

NSIDC' : 3.75-4.25M km2  LC Medium

Piomas : 3.50-4.00M km2  LC Medium

Juan C. García

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Re: September predictions challenge 2020
« Reply #16 on: June 10, 2020, 06:37:00 AM »
June poll for JAXA: 3.50-4.00M km2 MC (Medium confidence)
June poll for NSIDC: 4.00-4.50M km2 MC (Medium confidence)
June poll for PIOMAS: 4.00-4.50K km3 MC (Medium confidence)
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.

Paddy

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Re: September predictions challenge 2020
« Reply #17 on: June 10, 2020, 09:04:31 AM »
June predictions:
JAXA: 3.75 to 4.25 (Medium confidence)
PIOMAS: 4 to 4.5 (Medium confidence)
NSIDC: 4.25 to 4.75 (Medium confidence)

Freegrass

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Re: September predictions challenge 2020
« Reply #18 on: June 10, 2020, 10:38:40 AM »
JAXA: 2.50 and 3.00M km2 MC (High confidence)
NSIDC: 3.00 and 3.50M km2 MC (High confidence)
PIOMAS: 3.25 and 3.75 km3 MC (Medium confidence)
« Last Edit: June 10, 2020, 02:17:54 PM by Freegrass »
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Aluminium

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Re: September predictions challenge 2020
« Reply #19 on: June 10, 2020, 10:51:56 AM »
JAXA: 3.25-3.75, high.
NSIDC: 3.75-4.25 high.
PIOMAS: 4.25-4.75 high.

blumenkraft

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Re: September predictions challenge 2020
« Reply #20 on: June 10, 2020, 11:16:52 AM »
JAXA:  3.25 - 3.75, high
NSIDC: 3.75 - 4.25, high


PIOMAS: 4.25-4.75, high

Richard Rathbone

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Re: September predictions challenge 2020
« Reply #21 on: June 10, 2020, 01:55:32 PM »
We'll break the 2012 record with ease.
You need to put a number on that and state your confidence on that number in this thread.

Juan C. García

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Re: September predictions challenge 2020
« Reply #22 on: June 10, 2020, 07:01:21 PM »
This poll has been added to my September challenge. However I am sticking to the same deadline as the extent polls, so there are just 52 hours left for PIOMAS challenge entries.

https://forum.arctic-sea-ice.net/index.php/topic,3113.0.html
The end of June challenge vote is approaching...
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.

Wildcatter

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Re: September predictions challenge 2020
« Reply #23 on: June 11, 2020, 06:25:34 AM »
Am I in time?

Jaxa: 3.0 - 3.5 high
NSIDC: 3.25 - 3.75 medium
PIOMAS: 3.25 - 3.75 medium

 :D
« Last Edit: June 11, 2020, 06:36:46 AM by Wildcatter »

Richard Rathbone

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Re: September predictions challenge 2020
« Reply #24 on: June 11, 2020, 03:23:16 PM »
Am I in time?


Still over 9 hours to go. The polls closed at 1 a.m, so there's virtually a full day extra to the challenge deadline which is the midnight after the polls close.


Richard Rathbone

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Re: September predictions challenge 2020
« Reply #25 on: July 01, 2020, 11:37:53 AM »
Now open for the 3 July polls.

July deadline for challenge entries is midnight on July 11th UK time, some 23 hours after the polls close.

Please quote your June entry (if any) in your July entry.

...

June SIPN report has some interesting predictions.
https://www.arcus.org/sipn/sea-ice-outlook/2020/june 

University of Washington (PIOMAS in forecast mode) is making the lowest forecast of all SIPN entries, 3.2 +- 0.4
CPOM (Schroeder's melt pond statistic) is the statistical method making the lowest prediction, 3.8 +-0.5 with a 30% chance of a new record
The US Navy has the highest prediction 6.2 +-0.7
Nico Sun (posts here as Tealight) predicts 4.09-5.41 median 4.84 on the basis of his albedo model.
The UCL team (similar type of statistical model as Slater's) forecasts 3.96 +-0.34


oren

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Re: September predictions challenge 2020
« Reply #26 on: July 01, 2020, 02:37:27 PM »
JAXA: 3.5-4.0 (medium)
NSIDC: 4.0-4.5 (high)
PIOMAS 4.25-4.75 High
July:
JAXA: 3.5-4.0 (high)
NSIDC: 3.75-4.25 (medium)
PIOMAS 3.75-4.25 (medium)

Stephan

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Re: September predictions challenge 2020
« Reply #27 on: July 02, 2020, 09:42:07 PM »
I repeat the values I gave for the two polls:

JAXA Sep min. 3.75-4.25 M km² confidence high
NSIDC Sep ave. 4.00-4.50 M km² confidence high

I confirm the bins from July and their confidence.
As for PIOMAS Sep volume I stay with the 4.25-4.75 k km³ bin, high confidence.
It is too late just to be concerned about Climate Change

Phoenix

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Re: September predictions challenge 2020
« Reply #28 on: July 04, 2020, 11:03:38 PM »
JAXA 4.10-4.60 hi
NSIDC 4.25-4.75 hi
PIOMAS 4.5-5.0 hi

A lot has happened in the past month. The CAA looked pretty good a month ago and now looks like toast and now the CAB en fuego.

I'll try to stay on the optimistic side , but reality is what takes place when you are busy hoping for something else.

JAXA 3.75 - 4.25
NSIDC 4.00 - 4.50
PIOMAS 4.50 - 5.00

all hi.


Paddy

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Re: September predictions challenge 2020
« Reply #29 on: July 05, 2020, 08:23:43 AM »
I don't know. The distribution of the ice, with such low amounts in the central seas and such high amounts in the peripheral seas, suggests that a lot will melt out in my very humble total guess of an opinion. Taking all my predictions down half a bin, but sticking to Medium.

July predictions:
JAXA: 3.5 to 4.0 (Medium confidence)
PIOMAS: 3.75 to 4.25 (Medium confidence)
NSIDC: 4.0 to 4.5 (Medium confidence)

Aluminium

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Re: September predictions challenge 2020
« Reply #30 on: July 05, 2020, 11:52:42 AM »
JAXA: 3.25-3.75 high.
NSIDC: 3.75-4.25 high.
PIOMAS: 4.25-4.75 high.

JAXA: 3.25-3.75 high.
NSIDC: 3.75-4.25 high.
PIOMAS: 4.0-4.5 high.

PragmaticAntithesis

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Re: September predictions challenge 2020
« Reply #31 on: July 05, 2020, 10:58:26 PM »
June JAXA: 3.75-4.25 sqMm. Medium Confidence

June NSIDC: 4-4.5 sqMM. Medium Confidence

July JAXA: 3.5-4 sqMM. Medium Confidence

July NSDIC: 3.75-4.25 sqMM. Medium Confidence

July PIOMAS: 4,250-4,750 km3. Medium Confidence

Edit: corrected typo
« Last Edit: July 07, 2020, 01:37:42 PM by PragmaticAntithesis »
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igs

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Re: September predictions challenge 2020
« Reply #32 on: July 05, 2020, 11:50:46 PM »
July JAXA     : 3.50 - 4.00 km2 80% CL

July NSDIC   : 3.75 - 4.25 km2 80% CL

July PIOMAS : 4.25 - 4.75 km2 80% CL

The Walrus

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Re: September predictions challenge 2020
« Reply #33 on: July 06, 2020, 08:17:05 PM »
July JAXA:   3.75-4.25  Medium
July NSIDC:   4.25-4.75  High
July PIOMAS:  4.00-4.50  High

Juan C. García

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Re: September predictions challenge 2020
« Reply #34 on: July 07, 2020, 05:15:39 PM »
June poll for JAXA: 3.50-4.00M km2 MC (Medium confidence)
June poll for NSIDC: 4.00-4.50M km2 MC (Medium confidence)
June poll for PIOMAS: 4.00-4.50K km3 MC (Medium confidence)
July poll for JAXA: 3.50-4.00M km2 HC (High confidence)
July poll for NSIDC: 3.75-4.25M km2 HC (High confidence)
July poll for PIOMAS: 3.75-4.25K km3 HC (High confidence)
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.

slow wing

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Re: September predictions challenge 2020
« Reply #35 on: July 08, 2020, 08:34:32 AM »
Thanks for doing this.

I missed June so have some catching up to do! :P

July poll for JAXA: 3.50-4.00M km2 VHC (Very high confidence)
July poll for NSIDC: 4.00-4.50M km2 VHC (Very high confidence)
July poll for PIOMAS: 3.75-4.25K km3 VHC (Very high confidence).

Richard Rathbone

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Re: September predictions challenge 2020
« Reply #36 on: July 09, 2020, 02:10:27 AM »
June
JAXA: 3.75-4.25 M
NSIDC: 4.25-4.75 M
PIOMAS: 4.25-4.75 M



July
JAXA 3.5 - 4.0 M
NSIDC 4.0 - 4.5 M
PIOMAS 4.25 - 4.75 H

KenB

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Re: September predictions challenge 2020
« Reply #37 on: July 09, 2020, 10:18:43 PM »
July JAXA : 3.0-3.5, H
July NSIDC: 3.25-3.75, H
July PIOMAS:  3.5 - 4.0, H
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Juan C. García

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Re: September predictions challenge 2020
« Reply #38 on: July 11, 2020, 04:31:24 AM »
Just a reminder:
July deadline for challenge entries is midnight on July 11th UK time, some 23 hours after the polls close.

Please quote your June entry (if any) in your July entry.
;)
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.

blumenkraft

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Re: September predictions challenge 2020
« Reply #39 on: July 11, 2020, 01:43:27 PM »
No regrets, i stand by my initial vote. :)

Viggy

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Re: September predictions challenge 2020
« Reply #40 on: July 11, 2020, 06:39:54 PM »
I’m always quite pessimistic, so why change now?

JAXA: 2.0 - 2.5, High Confidence
NSIDC: 2.5 - 3.0, High Confidence

be cause

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Re: September predictions challenge 2020
« Reply #41 on: July 11, 2020, 07:04:45 PM »
.. says an optimist . :) b.c.
2007 + 5 = 2012 + 4 = 2016 + 3 = 2019 + 2 = 2021 
 (phew)

Viggy

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Re: September predictions challenge 2020
« Reply #42 on: July 12, 2020, 07:33:27 AM »
.. says an optimist . :) b.c.

Haha, I'm optimistic about my pessimistic forecast!

I guess my rationale for the low forecast is centered around the absolutely astounding SST anomalies in the Laptev and Kara Seas. It has been consistently increasing through the summer days and I can only see the persistent high pressure adding to it.

Whenever the inevitable Low Pressure system moves through that area in the late season, the mixing of all that warm sea water into the CAB ice is going to absolutely wreck extents.

Also, I think extent drops are more indicative of phase changes than incremental melting. And phase changes cause unanticipated-ly large drops (2012 being almost a 1M lower in extent that the previous record low of 2007).

blumenkraft

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Re: September predictions challenge 2020
« Reply #43 on: July 12, 2020, 09:52:23 AM »
Haha, I'm optimistic about my pessimistic forecast!

The circle is now full!  ;D ;D ;D

Jacobus

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Re: September predictions challenge 2020
« Reply #44 on: July 21, 2020, 09:44:05 PM »
July -- JAXA: 3-3.5, H
July -- PIOMAS: 3.75-4.25, L
July -- NSIDC: 3.25-3.75, M

glennbuck

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Re: September predictions challenge 2020
« Reply #45 on: July 21, 2020, 10:50:25 PM »
JAXA:  1.95-2.45 (HIGH)
NSIDC:  2.20-2.70 (HIGH)
« Last Edit: July 21, 2020, 11:43:14 PM by glennbuck »

Richard Rathbone

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Re: September predictions challenge 2020
« Reply #46 on: July 28, 2020, 03:32:28 PM »

June SIPN report has some interesting predictions.
https://www.arcus.org/sipn/sea-ice-outlook/2020/june 

University of Washington (PIOMAS in forecast mode) is making the lowest forecast of all SIPN entries, 3.2 +- 0.4
CPOM (Schroeder's melt pond statistic) is the statistical method making the lowest prediction, 3.8 +-0.5 with a 30% chance of a new record
The US Navy has the highest prediction 6.2 +-0.7
Nico Sun (posts here as Tealight) predicts 4.09-5.41 median 4.84 on the basis of his albedo model.
The UCL team (similar type of statistical model as Slater's) forecasts 3.96 +-0.34

July SIPN entries (based on June data) are now published.
PIOMAS forecast still thinks its going to be really low 3.35 +-0.4 though there is now one other model forecasting lower.
CPOM has backed off (due to low melt pond formation in early June) and is now saying 4.3 +-0.5
The US Navy still has the highest prediction but its dropped to 5.2 median 4.9-5.8 range
Nico Sun drops to median 4.41 range 3.96-4.74
The Slater model is one of the highest at 4.64
The UCL team is up to 4.3 +-0.27

oren

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Re: September predictions challenge 2020
« Reply #47 on: July 31, 2020, 07:24:20 AM »
JAXA: 3.5-4.0 (medium)
NSIDC: 4.0-4.5 (high)
PIOMAS 4.25-4.75 High
July:
JAXA: 3.5-4.0 (high)
NSIDC: 3.75-4.25 (medium)
PIOMAS 3.75-4.25 (medium)
August:
JAXA: 3.25-3.75 (high)
NSIDC: 3.50-4.00 (medium)
PIOMAS 3.50-4.00 (high)

Richard Rathbone

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Re: September predictions challenge 2020
« Reply #48 on: August 01, 2020, 04:48:14 PM »
Open for August entries. Oren provides a nice example of the preferred way to format them in the previous post.

Deadline is midnight UK time on August 11th which is approximately 20 hours after the polls close.

Paddy

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Re: September predictions challenge 2020
« Reply #49 on: August 02, 2020, 04:43:18 PM »
June predictions:
JAXA: 3.75 to 4.25 (Medium confidence)
PIOMAS: 4 to 4.5 (Medium confidence)
NSIDC: 4.25 to 4.75 (Medium confidence)

...
July predictions:
JAXA: 3.5 to 4.0 (Medium confidence)
PIOMAS: 3.75 to 4.25 (Medium confidence)
NSIDC: 4.0 to 4.5 (Medium confidence)

August predictions:
JAXA: 3.5 to 4.0 (High confidence)
PIOMAS: 3.75 to 4.25 (High confidence)
NSIDC: 3.75 to 4.25 (High confidence)

I'm not actually at all high in confidence, but thar's the way this game is scored.