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dmarcus

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Re: IJIS
« Reply #3600 on: December 24, 2016, 05:25:57 AM »
And now 2 consecutive days of declines, to fall back (just) below 11.4 million.

mhampton

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Re: IJIS
« Reply #3601 on: December 24, 2016, 05:59:59 AM »
I also find it funny that while 2010 has (for now) the lowest record until December 31, it was beaten on January 1 (albeit 2011) by 2016. The two lines crossed on the only day that the graph can't show that they crossed. In a weird way, 2016 is now in a race for last with 2016.

That's a special kind of funny.  If I had to bet I'd put my money on end-year 2016 over early-year 2016.  So much bizarre heat coming in from multiple directions.

jdallen

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Re: IJIS
« Reply #3602 on: December 24, 2016, 08:05:44 AM »
 Espen seems to be out of pocket.

So in his stead (without the graphic)

12/22/2016 - JAXA extent 11400739 down 90659 - Lowest for date
12/23/2016 - JAXA extent 11399061 down   1672 - Lowest for date
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pauldry600

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Re: IJIS
« Reply #3603 on: December 24, 2016, 11:21:14 AM »
Thanks for numbers.

My goodness. How will we get to my prediction of 12.057 by Dec 31 now?

Espen

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Re: IJIS
« Reply #3604 on: December 24, 2016, 11:23:40 AM »
IJIS:

11,399,061 km2(December 23, 2016)and lowest measured for the date.
Have a ice day!

be cause

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Re: IJIS
« Reply #3605 on: December 24, 2016, 03:52:53 PM »
thanks Espen .. I guess that will end any catch-up predictions for a while :) .
2007 + 5 = 2012 + 4 = 2016 + 3 = 2019 + 2 = 2021 + 1 =  ' if only we could have seen it coming ' ...

Tigertown

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Re: IJIS
« Reply #3606 on: December 24, 2016, 04:40:14 PM »
thanks Espen .. I guess that will end any catch-up predictions for a while :) .

Maybe even longer.
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Pmt111500

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Re: IJIS
« Reply #3607 on: December 25, 2016, 09:45:37 AM »
A bit late time for a stall. Have I uncharacteristically voted too high? Still exciting! Merry Christmas though to every forumite.

Paddy

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Re: IJIS
« Reply #3608 on: December 25, 2016, 10:57:11 AM »
The forum's modal vote (11.5 to 12) is looking pretty good right now, although there's still an outside chance it could go above 12. Would be very surprised if we weren't still at a record low at year end, however.
« Last Edit: December 25, 2016, 09:28:41 PM by Paddy »

Espen

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Re: IJIS
« Reply #3609 on: December 25, 2016, 12:38:56 PM »
IJIS:

11,401,745 km2(December 24, 2016)up 2,684  km2 from previous and lowest measured for the date.
Have a ice day!

jdallen

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Re: IJIS
« Reply #3610 on: December 25, 2016, 10:21:26 PM »
IJIS:

11,401,745 km2(December 24, 2016)up 2,684  km2 from previous and lowest measured for the date.
3 days with close to zero or negative growth.  4 days if you throw in the anemic 41K on the 21st.

The near-term forecast offers no cause for optimism.

While the 5 day forecast shows modest high pressure setting up over the eastern side of the Arctic, temperatures look to be persistently 5-10C above normal over both the entire Atlantic front and Chukchi.
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Espen

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Re: IJIS
« Reply #3611 on: December 25, 2016, 10:38:02 PM »
Just wondering about the Polar Bear situation at Svalbard with no sea ice?
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jdallen

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Re: IJIS
« Reply #3612 on: December 25, 2016, 11:53:22 PM »
Just wondering about the Polar Bear situation at Svalbard with no sea ice?
I'll have to dig some, but something I read recently indicated it was pretty dire - like close to a third have died back and they're haunting human settlements.
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Espen

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Re: IJIS
« Reply #3613 on: December 26, 2016, 10:21:29 AM »
IJIS:

11,506,615 km2(December 25, 2016)up 104,870  km2 from previous and lowest measured for the date.
Have a ice day!

Espen

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Re: IJIS
« Reply #3614 on: December 27, 2016, 09:40:03 AM »
IJIS:

11,621,488 km2(December 26, 2016)up 114,873 km2 from previous and lowest measured for the date.
Have a ice day!

Cato

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Re: IJIS
« Reply #3615 on: December 28, 2016, 10:10:03 AM »
And here we (nearly) are. Conditions in Barents have changed: no more compaction and colder conditions forecast for the next few days...

Espen

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Re: IJIS
« Reply #3616 on: December 28, 2016, 11:07:04 AM »
IJIS:

11,878,026 km2(December 28, 2016)up 256,538 km2 from previous and lowest measured for the date.
Have a ice day!

Jim Pettit

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Re: IJIS
« Reply #3617 on: December 28, 2016, 01:08:53 PM »
IJIS:

11,878,026 km2(December 28, 2016)up 256,538 km2 from previous and lowest measured for the date.

The data are a little off this morning, or premature, or something:

Dec. 26: 11,621,488 - Up 114,873 km2 from previous
Dec. 27: 11,775,707 - Up 154,219 km2 from previous
Dec. 28: 11,878,026 - Up 102,319 km2 from previous

Your 256,538 km2 increase is the total of what JAXA has for the 27th and the 28th combined.

Hmmmmmmmm...

Avalonian

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Re: IJIS
« Reply #3618 on: December 28, 2016, 01:22:04 PM »
Espen said, "...from previous," Jim, not from yesterday. Previous was two days ago. So yes, it's the total. Took me a minute or two to spot that, as well!  ;)

Definitely skirting with losing the title, though, and I understand that there's likely to be more growth over the next few days, based on the weather. Will it make the end of the month..?

Tigertown

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Re: IJIS
« Reply #3619 on: December 28, 2016, 02:20:15 PM »
A lot of this is ice growing back where it has recently been already. The conditions made it grow rapidly. It probably will do so another few days and then run out of anywhere to go due to warmer waters.
"....and the appointed time came for God to bring to ruin those ruining the earth." Revelation 11:18.

Downpuppy

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Re: IJIS
« Reply #3620 on: December 28, 2016, 03:02:29 PM »
How do they have today's result when the day is barely started?

Baffled, I am.

Jim Pettit

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Re: IJIS
« Reply #3621 on: December 28, 2016, 03:41:49 PM »
Espen said, "...from previous," Jim, not from yesterday. Previous was two days ago. So yes, it's the total. Took me a minute or two to spot that, as well!  ;)

Definitely skirting with losing the title, though, and I understand that there's likely to be more growth over the next few days, based on the weather. Will it make the end of the month..?

The main point of my comment wasn't, of course, an indictment on Espen's use of the term "previous"; it was, rather, to note that JAXA prematurely--and out of character--released the 12/27 and 12/28 numbers at the same time. Now, it's entirely possible, and in fact likely, that the 12/28 figures were ready far earlier in the day than normal, so JAXA went ahead with the odd double release. But it was more than appropriate to mention that SIE didn't increase by 257k in one day, but rather jumped >154k one day, and >102k the next. IOW: just keeping the record straight.

Avalonian

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Re: IJIS
« Reply #3622 on: December 28, 2016, 03:55:41 PM »
Sorry Jim - missed the point. I'll go back to lurking on this board!   :-[

gregcharles

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Re: IJIS
« Reply #3623 on: December 28, 2016, 05:22:11 PM »
I'm confused too. How was JAXA able to release data for 11/28 before the day was even half over, and fully 24 hours before they would normally release it?

Bill Fothergill

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Re: IJIS
« Reply #3624 on: December 29, 2016, 04:02:23 PM »
As Jim Pettit has already pointed out, the "weird" thing about the IJIS figures is not so much the date stamp, but the anomalous timing associated with the appearance of the figures.

Most of the organisations that provide this data do so with a one-day lag between the value of the date stamp and the day on which the data actually appears. For example, today is the 29th, and the NSIDC data (which has just appeared in the last few hours) is dated the 28th Dec. As you all know, this is the de facto standard we expect from the IJIS data.

However, this is a convention. One could just as easily set the date stamp to the date on which the data is (or would normally be) posted online. This, in fact, is the technique which the University of Bremen adopts - their graphs are set to show the date when the data was updated. The graph given in the link below should demonstrate the point...

http://www.iup.uni-bremen.de:8084/amsr2/extent_n_running_mean_amsr2_regular.png

Going back to the IJIS data, the starting point is to remember that JST is 9 hours ahead of GMT. (In Japan. there is no daylight saving offset to worry about.) Therefore, as it states on the ADS website, the target time for updating is 03:00 GMT, or 12:00 JST - i.e. midday.

Most people here will know that the IJIS data is actually a rolling two day average, and it is possible that this is the key to the quandary.

Perhaps there was some reason that the ADS people realised that the "normal" update scheduled to be posted on the 29th could not be accomplished. The ADS team might then have done something along the lines of the following...

Actual date 28th - Date stamp applied 27th - equates to average over 27th & 26th
Actual date 28th - Date stamp applied 28th - equates to single day value of 27th

I am not stating that this is an accurate representation of what happened; rather that this represents merely one of a variety of possible scenarios.

 

oren

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Re: IJIS
« Reply #3625 on: December 29, 2016, 08:47:07 PM »
Most people here will know that the IJIS data is actually a rolling two day average, and it is possible that this is the key to the quandary.
I didn't, so thanks for the clarification.

Cato

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Re: IJIS
« Reply #3626 on: December 30, 2016, 06:10:16 AM »
Don't want to anticipate Espen's post, I'll just say that it's gonna be a thrilling ending for year 2016... ;)

Espen

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Re: IJIS
« Reply #3627 on: December 30, 2016, 11:50:21 AM »
IJIS:

12,026,480 km2(December 29, 2016)
Have a ice day!

Espen

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Re: IJIS
« Reply #3628 on: December 31, 2016, 09:39:05 AM »
IJIS:

12,085,412 km2(December 30, 2016)and lowest measured for the date.
Have a ice day!

Jim Pettit

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Re: IJIS
« Reply #3629 on: December 31, 2016, 02:46:39 PM »
That 12/30 IJIS number marks the 200th day this year--and the 72nd consecutive one--that 2016 SIE has been the lowest on record. It's also the 323rd day of the year spent in the lowest three, an impressive 88.7% of the total. And while 2010 is within spitting distance of 2016 this morning (an increase of just over 106k will drop this year into second), that may be a little misleading, as this year has seen the lowest annual daily average, and by a spectacularly wide margin:



It'll be, er, interesting to see what 2017 has in store for the Arctic...

realitybytes

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Re: IJIS
« Reply #3630 on: December 31, 2016, 05:35:26 PM »
That 12/30 IJIS number marks the 200th day this year--and the 72nd consecutive one--that 2016 SIE has been the lowest on record. It's also the 323rd day of the year spent in the lowest three, an impressive 88.7% of the total. And while 2010 is within spitting distance of 2016 this morning (an increase of just over 106k will drop this year into second), that may be a little misleading, as this year has seen the lowest annual daily average, and by a spectacularly wide margin

Of course, that's just extent...

"Statistical tie for lowest extent" tells only part of the story - due to the deficit of FDD, volume is still far less than 2010, is it not?

Thickness, too, I would think. But that depends on area more than extent - how is year-end area doing?

magnamentis

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Re: IJIS
« Reply #3631 on: December 31, 2016, 05:51:14 PM »
as i see it thickness is one of the 3 components that make up volume LxBxH (german abbreviations)
or LxWxH (english abbreviations)

of those 3 thickness would be "H"

longwalks1

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Re: IJIS
« Reply #3632 on: December 31, 2016, 06:17:52 PM »
And when the final numbers come up, after being double-checked and tiny data corrections -, I would just love for the correct number of significant digits to be used.  A piddling bête noire, but it is mine.  Mis-usage of sig. digits was the easiest way for anyone to lose points in physics and chemistry in my day.  After reading some of the papers (and a good AGU youtube)  listed on this forum on the technology of the satellite data acquisition - I feel the excess digits inflates peoples beliefs in the precision of the sensing. 

Tor Bejnar

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Re: IJIS
« Reply #3633 on: December 31, 2016, 09:11:47 PM »
And when the final numbers come up, after being double-checked and tiny data corrections -, I would just love for the correct number of significant digits to be used.  A piddling bête noire, but it is mine.  Mis-usage of sig. digits was the easiest way for anyone to lose points in physics and chemistry in my day.  After reading some of the papers (and a good AGU youtube)  listed on this forum on the technology of the satellite data acquisition - I feel the excess digits inflates peoples beliefs in the precision of the sensing.
Hear, hear! 
My very first comments on a blog (Skeptical Science - many years ago) were about the misuse of significant digits in a publication.
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jdallen

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Re: IJIS
« Reply #3634 on: December 31, 2016, 10:49:42 PM »
And when the final numbers come up, after being double-checked and tiny data corrections -, I would just love for the correct number of significant digits to be used.  A piddling bête noire, but it is mine.  Mis-usage of sig. digits was the easiest way for anyone to lose points in physics and chemistry in my day.  After reading some of the papers (and a good AGU youtube)  listed on this forum on the technology of the satellite data acquisition - I feel the excess digits inflates peoples beliefs in the precision of the sensing.
Hear, hear! 
My very first comments on a blog (Skeptical Science - many years ago) were about the misuse of significant digits in a publication.
+1
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Shared Humanity

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Re: IJIS
« Reply #3635 on: January 01, 2017, 06:08:10 AM »
If you're going to be wrong, better to be precisely wrong.   :)

DavidR

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Re: IJIS
« Reply #3636 on: January 01, 2017, 08:44:48 AM »
Of course if you try to be too precisely right you will be wrong every time. Ice extent typically changes at thousands of square kilometres an hour and is calculated from several satellite passes A figure that is more precise than to the nearest 1000 kilometres is unacceptably precise.
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pikaia

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Re: IJIS
« Reply #3637 on: January 01, 2017, 11:34:23 AM »
As well as disliking excessive precision, I also dislike the absence of confidence limits. I wonder what they are for IJIS data?

oren

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Re: IJIS
« Reply #3638 on: January 01, 2017, 11:56:29 AM »
I dislike the absence of the IJIS number for the final day of the year  >:(

crandles

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Re: IJIS
« Reply #3639 on: January 01, 2017, 12:34:11 PM »
I dislike the absence of the IJIS number for the final day of the year  >:(

Seems to be showing on graph and in file.  ???

Espen

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Re: IJIS
« Reply #3640 on: January 01, 2017, 12:51:58 PM »
IJIS:

12,096,796 km2(December 31, 2016)up 11,384 km2 from previous and lowest measured for the date.
Have a ice day!

Espen

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Re: IJIS
« Reply #3641 on: January 01, 2017, 12:59:36 PM »
IJIS:

Total global sea ice extent 17,653,788 km2(December 31, 2016)down 1,833,860 km2 from December 31 2015, and lowest measured.
« Last Edit: January 01, 2017, 01:07:33 PM by Espen »
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Jim Pettit

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Re: IJIS
« Reply #3642 on: January 02, 2017, 02:44:25 PM »
Of course, that's just extent...

That's true--which is the reason I posted it in this extent-specific forum. :)

I, too, agree wholeheartedly with the precision of the various metrics we use--but until/unless we have access to different and better metrics, we have to live with what we have, while being aware of any intrinsic limitations. That's another reason, of course, data such as the annual averages shown in my chart can be more useful for comparative purposes than a specific and possibly imprecise daily number.

Shared Humanity

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Re: IJIS
« Reply #3643 on: January 02, 2017, 04:22:15 PM »
Of course if you try to be too precisely right you will be wrong every time. Ice extent typically changes at thousands of square kilometres an hour and is calculated from several satellite passes A figure that is more precise than to the nearest 1000 kilometres is unacceptably precise.

We're always wrong. Realizing this is evidence of the attainment of knowledge and an underlying intelligence.   ;)

Tigertown

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Re: IJIS
« Reply #3644 on: January 04, 2017, 05:27:26 AM »
I don't know what's up with JAXA, but at least they updated the concentration map.
I slowed down the second image for the final four days, and you can definitely see some improvement on the 3rd.

« Last Edit: January 04, 2017, 05:36:34 AM by Tigertown »
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Neven

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Re: IJIS
« Reply #3645 on: January 04, 2017, 12:21:31 PM »
I don't know what's up with JAXA, but at least they updated the concentration map.

It always takes some time for JAXA to resume data delivery in January. I'm sure they'll do so before the 10th.
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Benje

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Re: IJIS
« Reply #3646 on: January 04, 2017, 03:31:21 PM »
Thanks Espen for adding the Antarctic. I know it is off-thread but it is a hot topic that relates.

ArcticMelt

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Re: IJIS
« Reply #3647 on: January 04, 2017, 07:20:52 PM »

Espen

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Re: IJIS
« Reply #3648 on: January 05, 2017, 05:19:51 AM »
IJIS:

12,264,044 km2(January 3, 2017)lowest measured for the date.
Have a ice day!

Espen

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Re: IJIS
« Reply #3649 on: January 05, 2017, 05:30:09 AM »
IJIS:

12,370,038 km2(January 4, 2017)2nd lowest measured for the date.
Have a ice day!