Support the Arctic Sea Ice Forum and Blog

Poll

What will the IJIS Extent be on Dec 31st 2016?

More than 12.5m km2
3 (2.9%)
12 - 12.5m km2
27 (26.2%)
11.5 - 12m km2
37 (35.9%)
11 - 11.5m km2
26 (25.2%)
10.5 - 11m km2
7 (6.8%)
10 - 10.5m km2
3 (2.9%)
less than 10m km2
0 (0%)

Total Members Voted: 99

Voting closed: December 01, 2016, 08:25:11 AM

Author Topic: 2016 Year end IJIS Extent predictions  (Read 29325 times)

iwantatr8

  • New ice
  • Posts: 79
    • View Profile
  • Liked: 21
  • Likes Given: 4
2016 Year end IJIS Extent predictions
« on: November 21, 2016, 08:25:11 AM »
Ok,
Being as things are so unusual this year and there's a few of us still hanging around to watch, lets have your predictions for the IJIS Arctic Sea Ice Extent Prediction for the end of the year.

Poll open to vote changes until 1st December.

 :o

Neven

  • Administrator
  • First-year ice
  • Posts: 9470
    • View Profile
    • Arctic Sea Ice Blog
  • Liked: 1333
  • Likes Given: 617
Re: 2016 Year end IJIS Extent predictions
« Reply #1 on: November 21, 2016, 10:20:54 AM »
WARNING: I initially posted the wrong figures. Corrected now.

IJIS/JAXA SIE on December 31st for previous years (in million km2):

2007: 12.659
2008: 12.486
2009: 12.540
2010: 12.191
2011: 12.684
2012: 12.428
2013: 12.341
2014: 12.471
2015: 12.273
« Last Edit: November 21, 2016, 03:38:15 PM by Neven »
The enemy is within
Don't confuse me with him

E. Smith

charles_oil

  • Frazil ice
  • Posts: 337
    • View Profile
  • Liked: 38
  • Likes Given: 74
Re: 2016 Year end IJIS Extent predictions
« Reply #2 on: November 21, 2016, 10:43:14 AM »
Great Poll - thanks - Maybe we need one of those disclaimers?

Past Performance is Not Necessarily Indicative of Future Results

Indeed:
Past returns are not future returns. Past returns can be very misleading if there are reasons to believe that future market conditions are likely to be significantly different from those that shaped past returns.


Michael J

  • New ice
  • Posts: 23
    • View Profile
  • Liked: 0
  • Likes Given: 15
Re: 2016 Year end IJIS Extent predictions
« Reply #3 on: November 21, 2016, 10:50:29 AM »
I think a few people made my mistake and looked at the wrong graph. I changed my vote back to 11.5+. I think that there will be a rapid freeze of very thin ice.

jdallen

  • Young ice
  • Posts: 3410
    • View Profile
  • Liked: 650
  • Likes Given: 244
Re: 2016 Year end IJIS Extent predictions
« Reply #4 on: November 21, 2016, 12:26:49 PM »
I think a few people made my mistake and looked at the wrong graph. I changed my vote back to 11.5+. I think that there will be a rapid freeze of very thin ice.
Kinda what I'm expecting Michael.  It will be cold enough to force a freeze.  My doubt lies in whether or not the ice will thicken.
This space for Rent.

wanderer

  • Frazil ice
  • Posts: 156
    • View Profile
  • Liked: 0
  • Likes Given: 0
Re: 2016 Year end IJIS Extent predictions
« Reply #5 on: November 21, 2016, 02:08:46 PM »
IJIS/JAXA SIE on December 31st for previous years (in million km2):

2007: 11.612
2008: 11.513
2009: 11.727
2010: 11.360
2011: 11.636
2012: 11.504
2013: 11.669
2014: 11.824
2015: 11.519

From Espen:
"IJIS:

12,273,075 km2(December 31, 2015)2nd lowest measured for the date just 81,638 km2 above 2010."

Isn't this the right Data?

magnamentis

  • Guest
Re: 2016 Year end IJIS Extent predictions
« Reply #6 on: November 21, 2016, 02:26:22 PM »
IJIS/JAXA SIE on December 31st for previous years (in million km2):

2007: 11.612
2008: 11.513
2009: 11.727
2010: 11.360
2011: 11.636
2012: 11.504
2013: 11.669
2014: 11.824
2015: 11.519

From Espen:
"IJIS:

12,273,075 km2(December 31, 2015)2nd lowest measured for the date just 81,638 km2 above 2010."

Isn't this the right Data?

like you a got my data from the linked JAXA file as well as from the graphs based on those data, hence i got the values you mentioned but nowhere found the quoted values between 11-12M

the only other data are even higher and are from NSIDC while that is a 5 days average which would explain the difference.

i would propose that for polls based on sources that are not totally clear for everyone there should be a link provided to the dataset and/or graph to which the poll is related.

https://ads.nipr.ac.jp/vishop.ver1/data/graph/plot_extent_n_v2.csv

Neven

  • Administrator
  • First-year ice
  • Posts: 9470
    • View Profile
    • Arctic Sea Ice Blog
  • Liked: 1333
  • Likes Given: 617
Re: 2016 Year end IJIS Extent predictions
« Reply #7 on: November 21, 2016, 03:35:56 PM »
IJIS/JAXA SIE on December 31st for previous years (in million km2):

2007: 11.612
2008: 11.513
2009: 11.727
2010: 11.360
2011: 11.636
2012: 11.504
2013: 11.669
2014: 11.824
2015: 11.519

From Espen:
"IJIS:

12,273,075 km2(December 31, 2015)2nd lowest measured for the date just 81,638 km2 above 2010."

Isn't this the right Data?

Woops, I posted the monthly average!!! Sorry about that. And here I was, thinking I would make things clearer for people. I'm changing that comment right now.
The enemy is within
Don't confuse me with him

E. Smith

be cause

  • Nilas ice
  • Posts: 2441
    • View Profile
  • Liked: 1012
  • Likes Given: 1034
Re: 2016 Year end IJIS Extent predictions
« Reply #8 on: November 21, 2016, 04:47:36 PM »
I think I just turned tripolar ..
Conflict is the root of all evil , for being blind it does not see whom it attacks . Yet it always attacks the Son Of God , and the Son of God is you .

AbruptSLR

  • Multi-year ice
  • Posts: 19703
    • View Profile
  • Liked: 2268
  • Likes Given: 286
Re: 2016 Year end IJIS Extent predictions
« Reply #9 on: November 21, 2016, 05:18:55 PM »
I based my vote of between 10.5 & 11.0 on an extrapolation of Espen's attached plot for Nov 20 2016 through Dec 31 2016,

Edit: Updated to 11.0 to 11.5.
« Last Edit: November 26, 2016, 12:59:37 AM by AbruptSLR »
“It is not the strongest or the most intelligent who will survive but those who can best manage change.”
― Leon C. Megginson

Tor Bejnar

  • Young ice
  • Posts: 4606
    • View Profile
  • Liked: 879
  • Likes Given: 826
Re: 2016 Year end IJIS Extent predictions
« Reply #10 on: November 21, 2016, 06:01:15 PM »
I'm guessing the record low extent (for the day of year) will continue, and the difference between 2016 and the previous low year (mostly 2012, I think) will decrease by about half, projecting an 11.5 m Km2 extent on Dec. 31.  (I've voted for the bottom side of that 11.5 m.)
Arctic ice is healthy for children and other living things because "we cannot negotiate with the melting point of ice"

wehappyfew

  • Frazil ice
  • Posts: 170
    • View Profile
  • Liked: 48
  • Likes Given: 5
Re: 2016 Year end IJIS Extent predictions
« Reply #11 on: November 21, 2016, 07:22:02 PM »
I voted for 12 to 12.5...

Reasoning:

- Current sources of heat and moisture are N. Atlantic and N. Pacific. These areas will cool and mix with deeper coool water, as they do every winter, depriving the Arctic of the fuel for its anomalous water vapor feedback warming.

- A cold spell will eventually allow a thin layer of ice to form, even in the Kara and Barents seas. Once closed off, another source of water vapor will be lost.

- Many areas - CAB, E Siberian, Laptev, Can. Archipelago, and Beaufort - have already reached near 100% coverage (although CAB is currently dipping a bit). They will not contribute to any drastic extent shortfall. Chukchi will soon reach 100%

- Greenland Sea extent will be a function of Fram Export and circum-Greenland wind patterns. When Greenland Sea is higher, Baffin is lower, and vice versa. These two are unlikely to be drastically higher or lower in toto.

- Hudson Bay has always reached 100% by Dec 31. Winter is now finally arriving in Canada. Hudson Bay is unlikely to be much below 100% being surrounded by a very cold continent.

- St Lawrence is not important... usually near 0% on Dec 31.

- Okhotsk is below average temps. This is one of the marginal areas that will determine the extent during winter. It will freeze on time or even early.

- The N Pacific is cool. Extent could be above average in the Bering Sea once its shallow waters have cooled and overturned, and cool air and water flow north from the huge reservoir of coolth in the N Pacific.

That makes 10 areas with near normal extent. The 4 marginal areas that will determine the final year-end total are Okhotsk, Bering, Kara and Barents.

1. I think it is likely that Okhotsk will be above average due to its current below average temps, its proximity to very-much-below-average very cold Siberia, and its proximity to cool N pacific

2. I think Bering will be at or slightly above average extent - despite its current above average temps - for the same reasons as for Okhotsk.

3. Kara should eventually freeze, but it may be below average. It is anomalously warm right now, and there is no immediate source of coolth to bring it down.

4. Barents is very warm, has been highly variable in the past, and, like Kara, is upwind of cold Siberia so it cannot lose its heat easily. It should be far below average.

Sum total - eyeballing the excellent regional graphs by Wipneus - I think a new record low extent is possible for Dec 31, but just barely. Extent just above a record low is equally likely. So 12 - 12.5 encompasses my guesses. I would not be too surprised by a record low just below 12, but I would be very surprised by a return to near normal like the 2000's average of 12.75

The long-term effect of weaker and thinner ice from this alarmingly poor re-freeze is far more important than the extent... if it's a record low or near normal makes no difference. The thin ice will melt out early, barring a miraculously cold spring. Then albedo feedback at summer solstice will do its damage, even worse than last year.

The good news is the Trump/Bannon administration will cut the funding needed to monitor the Arctic so we can enjoy a brief interlude of blissful ignorance before the albedo/methane/water vapor feedbacks trigger the next hysteresis state-flip.

...
"If we’ve been bamboozled long enough, we tend to reject any evidence of the bamboozle. We’re no longer interested in finding out the truth. The bamboozle has captured us. It’s simply too painful to acknowledge, even to ourselves, that we’ve been taken" - Carl Sagan

Michael J

  • New ice
  • Posts: 23
    • View Profile
  • Liked: 0
  • Likes Given: 15
Re: 2016 Year end IJIS Extent predictions
« Reply #12 on: November 21, 2016, 09:48:43 PM »
I think a few people made my mistake and looked at the wrong graph. I changed my vote back to 11.5+. I think that there will be a rapid freeze of very thin ice.

I was using the right figures the first time apparently. Moved it back to 12-12.5. I think that it could be the lowest but not by a lot

magnamentis

  • Guest
Re: 2016 Year end IJIS Extent predictions
« Reply #13 on: November 21, 2016, 09:51:13 PM »
i voted 11.5 - 12.0M because even though thickness will not, i think that extent will finally cover the basin and come much closer to the latest record low values of slightly above 12M.

once more interesting while it think to hit the real value is a bit of luck, i'm glad if i'm one above or one below while it's nice to be spot on of course :-)

charles_oil

  • Frazil ice
  • Posts: 337
    • View Profile
  • Liked: 38
  • Likes Given: 74
Re: 2016 Year end IJIS Extent predictions
« Reply #14 on: November 21, 2016, 09:53:08 PM »
I too did a rough and ready extrapolation - using similar slope to existing as I dont see why there should be  much greater acceleration with all the warm water / air around over the next 5 weeks.  So went for 10 - 10.5 bucket.  NSIDC's handy diagram attached for reference.

Archimid

  • Young ice
  • Posts: 3511
    • View Profile
  • Liked: 899
  • Likes Given: 206
Re: 2016 Year end IJIS Extent predictions
« Reply #15 on: November 21, 2016, 10:51:11 PM »
charles_oil. Thanks for the map. I'm saving a copy.

I voted 10.5-11 bracket.I based most of of that decision comparing to 2015. SST over most of the growing periphery are higher than 2015. Temperatures are higher than 2015, and may remain that way for a few more weeks. I think it will follow a similar pattern to 2015 but worse.
I am an energy reservoir seemingly intent on lowering entropy for self preservation.

Paddy

  • Nilas ice
  • Posts: 1026
    • View Profile
  • Liked: 153
  • Likes Given: 151
Re: 2016 Year end IJIS Extent predictions
« Reply #16 on: November 21, 2016, 11:28:11 PM »
I went for 11.5 to 12, but my real guess is "around 12". Could be higher or lower.

Pmt111500

  • Guest
Re: 2016 Year end IJIS Extent predictions
« Reply #17 on: November 22, 2016, 02:58:50 AM »
12.15M for me, based on understanding until september...  ??? That looked like ice will be occupying the first place at least early November to january 2017. Seeing the data after the minimum... Lower?  :-\
« Last Edit: November 22, 2016, 04:11:00 AM by Pmt111500 »

JMP

  • Frazil ice
  • Posts: 114
    • View Profile
  • Liked: 19
  • Likes Given: 62
Re: 2016 Year end IJIS Extent predictions
« Reply #18 on: November 22, 2016, 07:42:32 AM »
Voted 11.5 to 12. 

As far as I can see it... the question is do we give more weight to following the same pattern as before? The idea that the sea ice may be limited to how much extent can freeze over a certain period of time or do we give weight to the idea that the sea ice will play catch-up? And, given the lower temperatures relative to existing extent, then more open sea will freeze into ice?  I'm of course going with the latter idea.  But! (of course) I have no way of really understanding this (well enough to be able to really predict) at the present moment.   Weather aside (even) it will be more than interesting to see how this plays out!!! 

icy voyeur

  • New ice
  • Posts: 63
    • View Profile
  • Liked: 0
  • Likes Given: 0
Re: 2016 Year end IJIS Extent predictions
« Reply #19 on: November 22, 2016, 11:32:59 AM »
I went for 11.5 to 12, but my real guess is "around 12". Could be higher or lower.

Just over 12 with more range on the error on the low side
(12.15) 12.05 (11.70) as a +/- one sigma guess

Entropy101

  • New ice
  • Posts: 10
    • View Profile
  • Liked: 0
  • Likes Given: 0
Re: 2016 Year end IJIS Extent predictions
« Reply #20 on: November 22, 2016, 12:36:06 PM »
I expect it will go over 12. But the quality and thickness will be worse than ever.

DavidR

  • Grease ice
  • Posts: 740
    • View Profile
  • Liked: 36
  • Likes Given: 3
Re: 2016 Year end IJIS Extent predictions
« Reply #21 on: November 23, 2016, 03:17:54 AM »
11-11.5 for two  reasons.
1. The Atlantic remains warmer than previous years and there is a long front which translates into plenty of scope for lower than normal ice.
2. The Pacific above 55N has been at near record temperatures all year indicating the likelihood of slow expansion in that area. Again its a long ice front and lower than usual growth can mean a lot smaller extent.

Having said all that  the first week of January is the week when the extent is most similar over recent years so an outcome nearer to 12 would not surprise.
Toto, I've a feeling we're not in Kansas anymore

Juan C. García

  • Young ice
  • Posts: 3359
    • View Profile
  • Liked: 1279
  • Likes Given: 1127
Re: 2016 Year end IJIS Extent predictions
« Reply #22 on: November 23, 2016, 07:41:39 AM »
12-12.5M km2

Just a hunch!
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

  • Moderator
  • First-year ice
  • Posts: 9805
    • View Profile
  • Liked: 3584
  • Likes Given: 3922
Re: 2016 Year end IJIS Extent predictions
« Reply #23 on: November 23, 2016, 07:53:54 PM »
Voted 11.5-12, it should be a record low but not by as much as the current gap, around 12 is the best guess.
Chukchi will indeed freeze over, but Kara Bering and Barents should keep some advantage compared to previous years. Okhotsk might close some of the gap, that's a wildcard.

gregcharles

  • New ice
  • Posts: 95
    • View Profile
  • Liked: 11
  • Likes Given: 2
Re: 2016 Year end IJIS Extent predictions
« Reply #24 on: November 23, 2016, 07:57:29 PM »
I voted 12 to 12.5. If I'm doing my 'rithmatic right, that means average increases of 84,359 to 97,180 over the next 39 days. Well, I hope we get that much!

Paddy

  • Nilas ice
  • Posts: 1026
    • View Profile
  • Liked: 153
  • Likes Given: 151
Re: 2016 Year end IJIS Extent predictions
« Reply #25 on: November 24, 2016, 07:41:13 AM »
Modified my vote to 12-12.5. I was always a bit on the fence around the "about 12" guess, and given that we've started to have a good recovery, the range of daily growth that gregcharles is taking about seems not unreasonable.

EDIT: Also, in a meta way, I've found this forum tends to estimate something slightly lower than what happens for future ice values, so picking a bin or two above the modal value is often a reasonable bet. Even though, in this case, some of the lowball estimates may be attributable to the wrong averages being posted previously.
« Last Edit: November 24, 2016, 07:52:53 AM by Paddy »

Pmt111500

  • Guest
Re: 2016 Year end IJIS Extent predictions
« Reply #26 on: November 24, 2016, 08:07:04 AM »
EDIT: Also, in a meta way, I've found this forum tends to estimate something slightly lower than what happens for future ice values, so picking a bin or two above the modal value is often a reasonable bet. Even though, in this case, some of the lowball estimates may be attributable to the wrong averages being posted previously.

As I'm partly responsible for the 'too low' results in the polls, i just try to compensate for 2007 and 2012... And the earlier model projections of 2080-90

CameraMan

  • New ice
  • Posts: 20
    • View Profile
  • Liked: 1
  • Likes Given: 17
Re: 2016 Year end IJIS Extent predictions
« Reply #27 on: November 25, 2016, 06:06:49 AM »
i'm seeing it about like Oran -- 11.9 is my guess atm.   Of course things have been so strange, nothing would surprise me now.

Michael J

  • New ice
  • Posts: 23
    • View Profile
  • Liked: 0
  • Likes Given: 15
Re: 2016 Year end IJIS Extent predictions
« Reply #28 on: November 26, 2016, 12:04:15 AM »
i'm seeing it about like Oran -- 11.9 is my guess atm.   Of course things have been so strange, nothing would surprise me now.

Having a bin from just under 12 to just over 12 would probably capture the majority of people by the sounds of it.

magnamentis

  • Guest
Re: 2016 Year end IJIS Extent predictions
« Reply #29 on: November 26, 2016, 05:21:24 PM »
i'm seeing it about like Oran -- 11.9 is my guess atm.   Of course things have been so strange, nothing would surprise me now.

Having a bin from just under 12 to just over 12 would probably capture the majority of people by the sounds of it.

exaxtly, i and many expect lower than 12,2 but not by a huge margin hence it will be between 11.8 and 12.1 IMO and that bin should be added, fully agree that the closeness to a "thousander should be consider with the bin appliance. :-)

to illustrate what we mean is the extrem example to put the bin limit to 12.1 or 12.3 LOL

Tor Bejnar

  • Young ice
  • Posts: 4606
    • View Profile
  • Liked: 879
  • Likes Given: 826
Re: 2016 Year end IJIS Extent predictions
« Reply #30 on: November 26, 2016, 05:37:40 PM »
I've moved up a bin to join the majority.  (It is now unseasonably hot up North instead of exceptionally unseasonably hot.)

It would be an interesting poll set-up to have overlapping bins:
11-11.5
11.25-11.75
11.5-12
11.75-12.25
12-12.5
etc.
so the folks who now argue for "12 +/- a little" can instead vote for being in the middle of a range.  And this way, there will 'always' be two correct vote ranges!
« Last Edit: December 08, 2016, 08:57:43 PM by Tor Bejnar »
Arctic ice is healthy for children and other living things because "we cannot negotiate with the melting point of ice"

gregcharles

  • New ice
  • Posts: 95
    • View Profile
  • Liked: 11
  • Likes Given: 2
Re: 2016 Year end IJIS Extent predictions
« Reply #31 on: December 08, 2016, 05:31:21 AM »
I voted 12 to 12.5. If I'm doing my 'rithmatic right, that means average increases of 84,359 to 97,180 over the next 39 days. Well, I hope we get that much!

Two weeks on, it's 76,616 per day for the next 25 days to get to 12 million. It's been a tough few days, but we're still sort of on track.

pauldry600

  • Frazil ice
  • Posts: 240
    • View Profile
    • weathergossip
  • Liked: 24
  • Likes Given: 3
Re: 2016 Year end IJIS Extent predictions
« Reply #32 on: December 09, 2016, 02:22:42 PM »
Dont think Ice will get past 13.5m this Winter but will prob tip 12m on December 31st. My guess is 12,057,576 haha

Gray-Wolf

  • Grease ice
  • Posts: 948
    • View Profile
  • Liked: 131
  • Likes Given: 458
Re: 2016 Year end IJIS Extent predictions
« Reply #33 on: December 09, 2016, 04:55:06 PM »
I'm always generally a little low on my guesses but I'm now thinking it could be sat in the 11.5 to 12 frame by Years end? Who'd have thunk it? Me being on the money for once?
KOYAANISQATSI

ko.yaa.nis.katsi (from the Hopi language), n. 1. crazy life. 2. life in turmoil. 3. life disintegrating. 4. life out of balance. 5. a state of life that calls for another way of living.
 
VIRESCIT VULNERE VIRTUS

gregcharles

  • New ice
  • Posts: 95
    • View Profile
  • Liked: 11
  • Likes Given: 2
Re: 2016 Year end IJIS Extent predictions
« Reply #34 on: December 22, 2016, 08:11:08 PM »
11,491,398 with 10 days to go. The 12 to 12.5 bucket is looking the most likely now, but it's not a lock. There's a chance pauldry600 will be exactly right, and then, of course, we'll burn him as a witch.  ;)

charles_oil

  • Frazil ice
  • Posts: 337
    • View Profile
  • Liked: 38
  • Likes Given: 74
Re: 2016 Year end IJIS Extent predictions
« Reply #35 on: December 24, 2016, 12:58:56 PM »
woooops - think its slipping back now

JdAllen on the IJIS thread:

12/22/2016 - JAXA extent 11400739 down 90659 - Lowest for date
12/23/2016 - JAXA extent 11399061 down   1672 - Lowest for date

So not sure it will make the 12-12.5 for Greg

Have we blinked and missed the chance for a poll on the winter 2016/17 maximum ???


mmghosh

  • New ice
  • Posts: 62
    • View Profile
  • Liked: 2
  • Likes Given: 63
Re: 2016 Year end IJIS Extent predictions
« Reply #36 on: December 25, 2016, 01:46:44 AM »
We may reach the 2017 maximum on Jan 1 2017... ;D

gregcharles

  • New ice
  • Posts: 95
    • View Profile
  • Liked: 11
  • Likes Given: 2
Re: 2016 Year end IJIS Extent predictions
« Reply #37 on: December 27, 2016, 08:24:06 PM »
Down to five days and up to 11,621,488. It will take an average increase of 75,702 per day to get to 12 million by the end of the year. That's a smaller daily average than a month ago, but way more than five days ago. Will it get there? I just want to go down on record at this point as saying I have no earthly clue.

Juan C. García

  • Young ice
  • Posts: 3359
    • View Profile
  • Liked: 1279
  • Likes Given: 1127
Re: 2016 Year end IJIS Extent predictions
« Reply #38 on: December 27, 2016, 09:01:08 PM »
Down to five days and up to 11,621,488. It will take an average increase of 75,702 per day to get to 12 million by the end of the year. That's a smaller daily average than a month ago, but way more than five days ago. Will it get there? I just want to go down on record at this point as saying I have no earthly clue.

is this an error on HYCOM??? look at NATL/Arctic...

Is it an error if AMSR2 shows it too?

If it is validated the AMSR2 image that Jim Hunt made public on the "2016 sea ice area and extent data" topic, then IJIS will decrease in extent today!
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

  • Young ice
  • Posts: 3359
    • View Profile
  • Liked: 1279
  • Likes Given: 1127
Re: 2016 Year end IJIS Extent predictions
« Reply #39 on: December 28, 2016, 05:25:02 AM »
Well, IJIS has a big increase: 154k km2.
It is possible that IJIS will reach the 12 million km2 this year.
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

  • Moderator
  • First-year ice
  • Posts: 9805
    • View Profile
  • Liked: 3584
  • Likes Given: 3922
Re: 2016 Year end IJIS Extent predictions
« Reply #40 on: December 30, 2016, 02:36:46 PM »
Surprisingly, IJIS passed 12 mil today, we're not at year-end yet so there's still the slim chance of a move back below the line. Still lowest for the date but by a very small margin, wondering if the year will end at lowest or not.

Jim Pettit

  • Nilas ice
  • Posts: 1175
    • View Profile
  • Liked: 41
  • Likes Given: 11
Re: 2016 Year end IJIS Extent predictions
« Reply #41 on: December 30, 2016, 02:54:22 PM »
Surprisingly, IJIS passed 12 mil today, we're not at year-end yet so there's still the slim chance of a move back below the line. Still lowest for the date but by a very small margin, wondering if the year will end at lowest or not.

Perhaps, or perhaps not. One thing is a rock solid lock, however: 2016 will have seen, by a substantial margin, the lowest yearly average SIE on record. 2nd place 2012 is laughably far behind:


Feeltheburn

  • Frazil ice
  • Posts: 214
    • View Profile
  • Liked: 12
  • Likes Given: 8
Re: 2016 Year end IJIS Extent predictions
« Reply #42 on: December 30, 2016, 05:16:02 PM »
How does IJIS relate to the data published at NSDIC? Are they different data sets or a different way of presenting a moving average of the same data? If I understand what has been said as to how the 2-day delayed average is determined for IJIS, the final sea ice extent for Dec 31 will in fact be the average of Dec 29 and Dec 30.

Based on trends seen at NSDIC, and if there is only 1 more day reported for IJIS, it looks like the final SIE will be about 12,150,000 km2, meaning it will be about tied for the lowest extent ever.
Feel The Burn!

crandles

  • Young ice
  • Posts: 3379
    • View Profile
  • Liked: 239
  • Likes Given: 81
Re: 2016 Year end IJIS Extent predictions
« Reply #43 on: December 30, 2016, 09:11:38 PM »
How does IJIS relate to the data published at NSDIC? Are they different data sets or a different way of presenting a moving average of the same data? If I understand what has been said as to how the 2-day delayed average is determined for IJIS, the final sea ice extent for Dec 31 will in fact be the average of Dec 29 and Dec 30.

Based on trends seen at NSDIC, and if there is only 1 more day reported for IJIS, it looks like the final SIE will be about 12,150,000 km2, meaning it will be about tied for the lowest extent ever.

Different data sets, different algorithms used.

Actually I don't think IJIS (or NSIDC) will be a simple arithmetic average of Dec 29 and Dec 30. I think they average the extent concentration percentage for all of the readings available over the two (five) days, then apply the 15% threshold to decide whether to include that cell in the extent number, then sum the area of the included cells.

That is not quite the same thing as applying 15% threshold to daily readings calculating an extent for each day then averaging the two day's extent numbers.

Juan C. García

  • Young ice
  • Posts: 3359
    • View Profile
  • Liked: 1279
  • Likes Given: 1127
Re: 2016 Year end IJIS Extent predictions
« Reply #44 on: December 30, 2016, 11:42:10 PM »
IJIS:

12,026,480 km2(December 29, 2016)

Well, seems that this will be close to the answer on this poll!  ;)
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.

Avalonian

  • Frazil ice
  • Posts: 141
    • View Profile
  • Liked: 26
  • Likes Given: 10
Re: 2016 Year end IJIS Extent predictions
« Reply #45 on: December 31, 2016, 01:44:29 AM »
Dont think Ice will get past 13.5m this Winter but will prob tip 12m on December 31st. My guess is 12,057,576 haha

   " IJIS:

    12,026,480 km2(December 29, 2016)"

OK, Pauldry600, we're looking for 31,096... and then we get  the ducking stool prepared.  :o

Paddy

  • Nilas ice
  • Posts: 1026
    • View Profile
  • Liked: 153
  • Likes Given: 151
Re: 2016 Year end IJIS Extent predictions
« Reply #46 on: January 01, 2017, 04:29:02 PM »
Looks like we have a winner, and also looks like Pauldry escapes the ducking stool.  Here's hoping 2017 somehow manages to break with 2016's habit of record low extents... but I'm not holding my breath.

oren

  • Moderator
  • First-year ice
  • Posts: 9805
    • View Profile
  • Liked: 3584
  • Likes Given: 3922
Re: 2016 Year end IJIS Extent predictions
« Reply #47 on: January 01, 2017, 06:40:22 PM »
Voted 11.5-12, it should be a record low but not by as much as the current gap, around 12 is the best guess.
Chukchi will indeed freeze over, but Kara Bering and Barents should keep some advantage compared to previous years. Okhotsk might close some of the gap, that's a wildcard.
So the basic logic was sound although the vote was wrong. Chukchi did freeze over at the last moment, Bering and Barents kept some advantage, although Kara did not. The CAB "Barents bite" supplied the added punch. Okhotsk came in above average but not enough to reverse the record low. It's been a very interesting first half of the freezing season, and the extent numbers fail to tell most of the story, but it's still fitting that the year finished at record low.

charles_oil

  • Frazil ice
  • Posts: 337
    • View Profile
  • Liked: 38
  • Likes Given: 74
Re: 2016 Year end IJIS Extent predictions
« Reply #48 on: January 01, 2017, 07:26:25 PM »
How about a Poll on 2016/2017 winter max ?

when and how much - I think poll may need to end early though (mid jan)... just in case.

iwantatr8

  • New ice
  • Posts: 79
    • View Profile
  • Liked: 21
  • Likes Given: 4
Re: 2016 Year end IJIS Extent predictions
« Reply #49 on: January 01, 2017, 11:30:44 PM »
Well it's all over now, but what an interesting couple of months it's been.

Given that 64 of the 103 voters got within 0.5m sqkm of the final outcome is indicative of the experience and knowledge that the forum provides.

2017 promises to be another extraordinarily year in the tale of sea ice, not only in the arctic but the Antarctic too.

All the best for 2017 everyone!