Support the Arctic Sea Ice Forum and Blog

Poll

When will we next see a new lowest 365 day trailing average extent?

2019
0 (0%)
Within the first three months of 2020
10 (62.5%)
Within months 4 to 6 of 2020
2 (12.5%)
Later in 2020
2 (12.5%)
2021
0 (0%)
2022 or later
2 (12.5%)

Total Members Voted: 14

Voting closed: September 26, 2019, 11:37:24 AM

Author Topic: 365 day average extent poll  (Read 18343 times)

gerontocrat

  • First-year ice
  • Posts: 9632
    • View Profile
  • Liked: 3810
  • Likes Given: 29
Re: 365 day average extent poll
« Reply #50 on: October 02, 2020, 01:02:49 PM »
But now daily extent gains have trended well below average so a 2020 record low is in play again.

On the other hand 2019 extent gains are also about to slow substantially, which led to a record low October monthly average last year. But from late October 2019 extent gains accelerated.

Graphs & table attached.
« Last Edit: October 02, 2020, 04:51:09 PM by gerontocrat »
"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

  • First-year ice
  • Posts: 9632
    • View Profile
  • Liked: 3810
  • Likes Given: 29
Re: 365 day average extent poll
« Reply #51 on: October 05, 2020, 01:07:54 PM »
A 2020 record low 365 day minimum still in play.

A small milestone just passed. In late 2019 the progress towards a record low petered out on the 6th December at a 365 day average of 9.751 million km2. The 4/10/2020 365 day average is just  below 9.750 million km2.

« Last Edit: October 05, 2020, 10:59:40 PM by gerontocrat »
"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)

Paddy

  • Grease ice
  • Posts: 710
    • View Profile
  • Liked: 66
  • Likes Given: 81
Re: 365 day average extent poll
« Reply #52 on: October 05, 2020, 09:10:11 PM »
A 2020 record low 365 day minimum still in play.

A small milestone just passed. In late 2019 the progress towards a record low petered out on the 6th December at a 365 day average of 9.751 million km2. The 4/10/2020 365 day average is just  below 3.750 million km2.

I think you mean 9.750?

gerontocrat

  • First-year ice
  • Posts: 9632
    • View Profile
  • Liked: 3810
  • Likes Given: 29
Re: 365 day average extent poll
« Reply #53 on: October 05, 2020, 11:00:04 PM »
A 2020 record low 365 day minimum still in play.

A small milestone just passed. In late 2019 the progress towards a record low petered out on the 6th December at a 365 day average of 9.751 million km2. The 4/10/2020 365 day average is just  below 3.750 million km2.

I think you mean 9.750?
bummer
"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

  • First-year ice
  • Posts: 9632
    • View Profile
  • Liked: 3810
  • Likes Given: 29
Re: 365 day average extent poll
« Reply #54 on: October 16, 2020, 11:44:53 AM »
From the 4th to the 14th October 2020 daily extent gains were mostly above 2019 extent gains. The possibility of a 2020 record low 365 day average seemed to slip away.

On the 15th, a very low daily 2020 extent gain reversed the trend. But will it continue enough to bring a 2020 record low into play? It all depends on whether 2020 follows 2012 and 2019 in an October rebound in arctic sea ice extent, or follows 2016, which did not.
"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)

Paddy

  • Grease ice
  • Posts: 710
    • View Profile
  • Liked: 66
  • Likes Given: 81
Re: 365 day average extent poll
« Reply #55 on: October 18, 2020, 04:15:40 PM »
With high temps forecast for the ten days ahead, I expect the gap with 2019 can only widen in the immediate future. A new minimum this year looks ever more likely.

gerontocrat

  • First-year ice
  • Posts: 9632
    • View Profile
  • Liked: 3810
  • Likes Given: 29
Re: 365 day average extent poll
« Reply #56 on: October 18, 2020, 06:49:09 PM »
Getting to be very interesting again...

click an image to make it bigger
"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

  • Moderator
  • First-year ice
  • Posts: 6424
    • View Profile
  • Liked: 2388
  • Likes Given: 2043
Re: 365 day average extent poll
« Reply #57 on: October 18, 2020, 07:14:01 PM »
Thanks for these updates Gero.
Looking at the long term chart it is quite obvious that Arctic sea ice has not been stable since 2012 (or 2007) as some people think.
« Last Edit: October 21, 2020, 11:18:06 AM by oren »

gerontocrat

  • First-year ice
  • Posts: 9632
    • View Profile
  • Liked: 3810
  • Likes Given: 29
Re: 365 day average extent poll
« Reply #58 on: October 19, 2020, 10:32:11 AM »
Back on track for a 365 day trailing average record low in December 2020.

but......
"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

  • First-year ice
  • Posts: 9632
    • View Profile
  • Liked: 3810
  • Likes Given: 29
Re: 365 day average extent poll
« Reply #59 on: October 21, 2020, 10:39:13 AM »
Confidence in a record low 365 day trailing average in 2020 increases day by 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)

gerontocrat

  • First-year ice
  • Posts: 9632
    • View Profile
  • Liked: 3810
  • Likes Given: 29
Re: 365 day average extent poll
« Reply #60 on: October 23, 2020, 01:12:58 PM »
The 365 day trailing average continues to reduce at an accelerating rate. Given that 2019 daily extent gains are about to rocket upwards, this continue for at least a few days more. A reminder - it is the amount by which 2020 extent is lower than 2019 that determines the rate by which this average reduces.

A record low 365 day average in November is now a possibility, though perhaps not a probability.
"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

  • First-year ice
  • Posts: 9632
    • View Profile
  • Liked: 3810
  • Likes Given: 29
Re: 365 day average extent poll
« Reply #61 on: October 27, 2020, 12:04:58 PM »
The 365 day trailing average continues to reduce at an accelerating rate. Given that 2019 daily extent gains continue to be very high this could continue for at least a few days more.

However, from around the 5th November daily gains in 2019 moderated. If, on the other hand, 2020 extent gains sharply increase due to the catch-up expected due to the very late late re-freeze, 2020 extent could catch up with 2019 very quickly indeed.

A reminder - it is the amount by which 2020 extent is lower than 2019 that determines the rate by which this average reduces.

A record low 365 day average in mid November is now a tantalising possibility.
"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

  • First-year ice
  • Posts: 9632
    • View Profile
  • Liked: 3810
  • Likes Given: 29
Re: 365 day average extent poll
« Reply #62 on: October 28, 2020, 01:59:15 PM »
NSIDC Area Data

Here is the data on when NSIDC Area might be at a record low - and we are currently talking about mid-2021. Between now and then much can happen - and probably will.

____________________________________
ps: In a week or so I should be able to do the same for PIOMAS volume data to 0ct-31 / Nov-1.
Yet another very different story.



"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)

Tor Bejnar

  • Young ice
  • Posts: 3724
    • View Profile
  • Liked: 653
  • Likes Given: 441
Re: 365 day average extent poll
« Reply #63 on: October 29, 2020, 02:52:05 PM »
A sine wave might be a smarter fit for the data (and then someone will need to figure out what the decadal influence is ...).  That polynomial certainly shows why extrapolating can be dangerous!
Arctic ice is healthy for children and other living things.

gerontocrat

  • First-year ice
  • Posts: 9632
    • View Profile
  • Liked: 3810
  • Likes Given: 29
Re: 365 day average extent poll
« Reply #64 on: October 29, 2020, 02:53:12 PM »
The 365 day trailing average continues to reduce at an accelerating rate. However, 2020 daily gains are on the increase.

A reminder - it is the amount by which 2020 extent is lower than 2019 that determines the rate by which this average reduces.

A record low 365 day average in mid November is still a tantalising possibility.
"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

  • First-year ice
  • Posts: 9632
    • View Profile
  • Liked: 3810
  • Likes Given: 29
Re: 365 day average extent poll
« Reply #65 on: October 29, 2020, 03:21:12 PM »
A sine wave might be a smarter fit for the data (and then someone will need to figure out what the decadal influence is ...).  That polynomial certainly shows why extrapolating can be dangerous!
I left the polynomial fit on the graph just to remind myself that the best fit according to R2 is not always the best fit.
"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

  • First-year ice
  • Posts: 9632
    • View Profile
  • Liked: 3810
  • Likes Given: 29
Re: 365 day average extent poll
« Reply #66 on: November 01, 2020, 12:03:05 PM »
JAXA Sea Ice Extent 365 day average

Despite the current very high sea ice extent gains, a record low 365 day average in November still looks very possible.
"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)

Positive retroaction

  • New ice
  • Posts: 50
    • View Profile
  • Liked: 28
  • Likes Given: 148
Re: 365 day average extent poll
« Reply #67 on: November 01, 2020, 09:01:59 PM »
thank you for all this data Gerontocrat
Are there any 365-day volume survey charts (month by month certainly)? I don't seem to have seen any on the forum
thank you
Sorry, excuse my bad english

gerontocrat

  • First-year ice
  • Posts: 9632
    • View Profile
  • Liked: 3810
  • Likes Given: 29
Re: 365 day average extent poll
« Reply #68 on: November 03, 2020, 06:46:59 PM »
thank you for all this data Gerontocrat
Are there any 365-day volume survey charts (month by month certainly)? I don't seem to have seen any on the forum
thank you
You will see something on 365 day averages on this thread when we have the October PIOMAS data.

Meanwhile

NSIDC Sea Ice Area 365 day Average

In contrast wth JAXA extent, the NSIDC sea ice area 365 day average is still more than 300k above the early 2017 record low.
It is reducing, and could be a record low by mid-2021 if 2020-21 area stays well below 2019-20 area.
"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)

Positive retroaction

  • New ice
  • Posts: 50
    • View Profile
  • Liked: 28
  • Likes Given: 148
Re: 365 day average extent poll
« Reply #69 on: November 04, 2020, 12:02:01 AM »
thank you for all this data Gerontocrat
Are there any 365-day volume survey charts (month by month certainly)? I don't seem to have seen any on the forum
thank you
You will see something on 365 day averages on this thread when we have the October PIOMAS data.


Thank you, so I will look that
And thank's for this interesting data for the extent
Sorry, excuse my bad english

gerontocrat

  • First-year ice
  • Posts: 9632
    • View Profile
  • Liked: 3810
  • Likes Given: 29
Re: 365 day average extent poll
« Reply #70 on: November 04, 2020, 05:21:27 PM »
And here we are... PIOMAS Volume 365 Day Trailing Average.

The current record low was reached in August 2017 at 12,675 km3.
2020 daily volume has been lower than 2019 only since September 16th, and is currently 13,590 km3, 1,023 km3 above that record low.

So a long way to go, at the current rate a new record low in late 2022. BUT there are bound to be bumps in the road on the way.

« Last Edit: November 05, 2020, 12:25:38 AM by gerontocrat »
"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)

Positive retroaction

  • New ice
  • Posts: 50
    • View Profile
  • Liked: 28
  • Likes Given: 148
Re: 365 day average extent poll
« Reply #71 on: November 04, 2020, 11:50:06 PM »
Thank you, very informative
Sorry, excuse my bad english

gerontocrat

  • First-year ice
  • Posts: 9632
    • View Profile
  • Liked: 3810
  • Likes Given: 29
Re: 365 day average extent poll
« Reply #72 on: November 05, 2020, 11:14:57 AM »
JAXA Extent Data

If 2020 daily extent gains do not substantially reduce in the next few days 2020 sea ice extent will become greater than 2019. At that time the 365 day trailing average would start to increase.
"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

  • First-year ice
  • Posts: 9632
    • View Profile
  • Liked: 3810
  • Likes Given: 29
Re: 365 day average extent poll
« Reply #73 on: November 07, 2020, 11:08:06 AM »
JAXA Extent Data

If 2020 daily extent gains do not substantially reduce in the next few days 2020 sea ice extent will become greater than 2019. At that time the 365 day trailing average would start to increase.
Wherupon 2020 daily extent gains have greatly reduced.
With just 25k to go, if extent gains from now are resonably close to the 10 year average a record low 365b day trailing average this year is pretty much a certainty.
"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)

Paddy

  • Grease ice
  • Posts: 710
    • View Profile
  • Liked: 66
  • Likes Given: 81
Re: 365 day average extent poll
« Reply #74 on: November 07, 2020, 11:31:51 AM »
I think the question may start to be not whether we'll get a new minimum in the next few months, but when and how deep. Given how high 2020 went in Jan to March, it could go a fair bit deeper still in the first few months of next year.

gerontocrat

  • First-year ice
  • Posts: 9632
    • View Profile
  • Liked: 3810
  • Likes Given: 29
Re: 365 day average extent poll
« Reply #75 on: November 11, 2020, 12:36:55 PM »
Once again increases in extent gains push the date for a record low 365 day trailing average back to mid-December.

With just 22k reduction for a record low, what a tease.
"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

  • First-year ice
  • Posts: 9632
    • View Profile
  • Liked: 3810
  • Likes Given: 29
Re: 365 day average extent poll
« Reply #76 on: November 16, 2020, 11:15:27 AM »
JAXA Srctic sea ice extent data

I attach latest table and graph - just 18k to go for a new record low 365 day trailing average
« Last Edit: November 16, 2020, 04:56:42 PM by gerontocrat »
"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

  • First-year ice
  • Posts: 9632
    • View Profile
  • Liked: 3810
  • Likes Given: 29
Re: 365 day average extent poll
« Reply #77 on: November 19, 2020, 10:38:12 AM »
JAXA Arctic sea ice extent data

I attach latest table and graphs

- just over 15k to go for a new record low 365 day trailing average,
- the trailing average just went below 9.7 million #km2.

The last graph attached shows why 2020 extent was catching up with 2019 from late October to early November and why now the gap is increasing.
« Last Edit: November 19, 2020, 10:44:49 AM by gerontocrat »
"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

  • First-year ice
  • Posts: 9632
    • View Profile
  • Liked: 3810
  • Likes Given: 29
Re: 365 day average extent poll
« Reply #78 on: November 22, 2020, 11:50:38 AM »
JAXA Arctic sea ice extent data

I attach latest table and graphs

-12k to go for a new record low 365 day trailing average.
- at the current rate of daily reduction in the first week of December.....but
"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

  • Moderator
  • First-year ice
  • Posts: 6424
    • View Profile
  • Liked: 2388
  • Likes Given: 2043
Re: 365 day average extent poll
« Reply #79 on: November 22, 2020, 12:12:47 PM »
2019 underperforms for the next 10 days, so it will be tough.

gerontocrat

  • First-year ice
  • Posts: 9632
    • View Profile
  • Liked: 3810
  • Likes Given: 29
Re: 365 day average extent poll
« Reply #80 on: November 25, 2020, 12:23:04 PM »
2019 underperforms for the next 10 days, so it will be tough.

JAXA Arctic sea ice extent data

,,,,but happened, and is likely to continue happening - see Oren's post

I attach latest table and graphs.
- 2020 extent now only 147k less than 2019,
-10k to go for a new record low 365 day trailing average, which  at the current rate of daily reduction happens on the 20th of December.....but could easily be delayed indefinitely.
"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

  • First-year ice
  • Posts: 9632
    • View Profile
  • Liked: 3810
  • Likes Given: 29
Re: 365 day average extent poll
« Reply #81 on: November 27, 2020, 10:59:57 AM »
2019 underperforms for the next 10 days, so it will be tough.

JAXA Arctic sea ice extent data

,,,,but happened, and is likely to continue happening - see Oren's post

I attach latest table and graphs.
- 2020 extent now only 147k less than 2019,
-10k to go for a new record low 365 day trailing average, which  at the current rate of daily reduction happens on the 20th of December.....but could easily be delayed indefinitely.
What a tease - 2020 daily extent gains drop to below zero...
"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)