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Andre

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Re: 2016 sea ice area and extent data
« Reply #1050 on: November 19, 2016, 05:20:04 PM »
Wipneus, I really appreciate the increased focus on global extent.

I understand that most of the time, it is somewhat frowned upon due to the different mechanisms controling the two poles but given the current anomalies, I think a more thorough look at global ice values is more than justified.

Keep up the good work!

musickna

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Re: 2016 sea ice area and extent data
« Reply #1051 on: November 19, 2016, 05:50:53 PM »
Last freeze season was very exciting. This one is riveting. Thanks to everyone here. I visit every day.

Ditto. This, and other forums here, are invaluable to me as a source of front line information. I've here for years, don't contribute because this is not my field of expertise (I'm a biochemist), but very much appreciate what's posted.

Tigertown

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Re: 2016 sea ice area and extent data
« Reply #1052 on: November 19, 2016, 07:19:03 PM »
Wipneus, I really appreciate the increased focus on global extent.

I understand that most of the time, it is somewhat frowned upon due to the different mechanisms controling the two poles but given the current anomalies, I think a more thorough look at global ice values is more than justified.

Keep up the good work!

Global extent may be more important than we know. I mean usually when one Pole is low the other is at least on the upswing in extent, with the seasons off-set. When one fails to do it's job and take up the other's slack, both may lose, like a tag team.

charles_oil

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Re: 2016 sea ice area and extent data
« Reply #1053 on: November 19, 2016, 07:48:57 PM »
It seems that the drop this year is at a much lower extent than in previous years - I used the Chartic graph and changed the scales.  Looks like there are a number of years where there are drops when the area is around 9.25m - 10m km2, but it seems unusual at 8.5m km2.

http://nsidc.org/arcticseaicenews/charctic-interactive-sea-ice-graph/

Archimid

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Re: 2016 sea ice area and extent data
« Reply #1054 on: November 19, 2016, 08:20:29 PM »
I think global extent is only useful if both extents are high or both low. If one is high and the other low then important information is lost due to the overlap.
I am an energy reservoir seemingly intent on lowering entropy for self preservation.

bbr2314

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Re: 2016 sea ice area and extent data
« Reply #1055 on: November 19, 2016, 08:21:29 PM »
I think global extent is only useful if both extents are high or both low. If one is high and the other low then important information is lost due to the overlap.
how about if they are both at record lows... lol... you don't think it's useful?  :o

Archimid

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Re: 2016 sea ice area and extent data
« Reply #1056 on: November 19, 2016, 08:29:27 PM »
That's what I said. If both are record high, or both are record low, the the metric is good on its own. If one is record high/low while the other one is not, then a caveat must be made.
I am an energy reservoir seemingly intent on lowering entropy for self preservation.

BornFromTheVoid

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Re: 2016 sea ice area and extent data
« Reply #1057 on: November 19, 2016, 09:27:40 PM »
Unless we see an increase in the daily NSIDC extent of at least 142k tomorrow, the 5 day average will continue to drop. 2 days of drops is already a record for November so 3 days and possibly more will only emphasise just how bizarre the current sea ice conditions are.

It also looks like the 7 day average change could switch from record largest gain to record lowest gain in just 5 days.

It's like the spinning top's final wobbles before it keels over.

dnem

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Re: 2016 sea ice area and extent data
« Reply #1058 on: November 19, 2016, 10:11:38 PM »
It's like the spinning top's final wobbles before it keels over.

I hope this isn't too OT, but BFTV basically raised the issue.  I often hear statements to the effect that the variability of complex systems increase before they move to a new state or equilibrium.  Would most here agree that variability is increasing in measures like SIE, as well as the arctic weather, generally, and that it is indicative that the system is approaching a change of state?  Does complex systems theory support this general interpretation?

Tigertown

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Re: 2016 sea ice area and extent data
« Reply #1059 on: November 19, 2016, 10:55:15 PM »
Just doing a visual on Polar view, I don't see any growth on any front. Everything is in the same place as yesterday. I think we have reached a virtual stall now.

« Last Edit: November 19, 2016, 11:10:59 PM by Tigertown »

bbr2314

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Re: 2016 sea ice area and extent data
« Reply #1060 on: November 20, 2016, 12:48:26 AM »
Just doing a visual on Polar view, I don't see any growth on any front. Everything is in the same place as yesterday. I think we have reached a virtual stall now.
Should continue for next five days at least if DMI is accurate. Looks like the Atlantic front will continue its slight retreat which should be evened out by minimal gains in Kara and Hudson/Baffin while the Pac front is also stalled.

Tigertown

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Re: 2016 sea ice area and extent data
« Reply #1061 on: November 20, 2016, 05:13:02 AM »
Yes, we did actually lose a few thousand km2 today, per JAXA. I don't know how much longer this will go on, whether a few days or more, but this has cumulative effects that will carry over to next Spring, no doubt.

Edit: DMI is not alone, as Climate Reanalyzer has the temp. anomaly still just under 4o C above normal at 7 days out.

« Last Edit: November 20, 2016, 05:52:41 AM by Tigertown »

BornFromTheVoid

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Re: 2016 sea ice area and extent data
« Reply #1062 on: November 20, 2016, 06:25:00 PM »
Update for the week to November 19th

The current 5 day trailing average is on 8,613,000km2 while the 1 day extent is at 8,560,000km2.

(All the following data is based on a trailing 5 day average)
The daily anomaly (compared to 81-10) is at -2,166,000km2, an increase from -1,891,000km2 last week. The anomaly compared to the 07, 11 and 12 average is at -1,143,000km2, an increase from -753,000km2 last week. We're currently lowest on record, the same as last week.



The average daily change over the last 7 days was +28.7k/day, compared to the long term average of +68.0k/day, and the 07, 11 and 12 average of +80.2k/day.
The average long term change over the next week is +65.8k/day, with the 07, 11, and 12 average being +83.6k/day.



The extent increase so far this November is the 8th largest on record. To achieve the largest increase, a gain of at least 121.6k/day is required (at least +156.7k/day with with single day values), while the smallest increase requires a loss of at least 31.5k/day (more than 30.3k/day with single day values) and an average increase requires a gain of 47.7k/day (66.5k/day with single day values).


Shared Humanity

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Re: 2016 sea ice area and extent data
« Reply #1063 on: November 20, 2016, 11:24:41 PM »
BFTV....

I would like to thank you for posting these charts on a regular schedule with little commentary....just the data. It helps to ground ourselves and allows us to recognize that this recent, unprecedented stall could just be random fluctuations in a increasingly weak freeze season trend.

At any rate, it keeps me from running hysterically into the darkness, screaming like a raving lunatic.

timallard

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Re: 2016 sea ice area and extent data
« Reply #1064 on: November 21, 2016, 03:14:22 AM »
Consider this thesis for a cause of the stall being that the ice-state is generally now, "rotten ice", including what's left of multi-year ice such that a ship hardly need slow down.

The APL-UW cored rotten ice last fall: https://www.youtube.com/watch?v=gD2Dki8VFPk]"Assessing the Habitability and Physical Structure of Rotting First-year Arctic Sea Ice "; APL-UW; 6:38; [url]https://www.youtube.com/watch?v=gD2Dki8VFPk[/url]

They also found that a warm water layer was about 20m down and mixed up during a storm: "ARCTIC SEA STATE; Sea State and Boundary Layer Physics of the Emerging Arctic Ocean"; mainly in the Beaufort; APL-UW; 5:13; https://www.youtube.com/watch?v=tDmM5zsxd4E?

First speaker describes conditions in the Beaufort Sea; "Café Scientifique - Arctic Sea Ice: A Slippery Slope?"; with other speakers; 1:32:27;

This implies the heat-gain of ice-loss is taking much longer in fall to reverse if it can at all, today's albedo-loss is worth 25-years of USA power compared to the 1980-2010 sea-ice cover, about 3,800-TeraJoule-hours/yr for USA power = 95,000-Twh a year in energy in the water in fall more than melt-out.

Looks like a Last Hurrah to a bluewater event isn't many years distant.
-tom

budmantis

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Re: 2016 sea ice area and extent data
« Reply #1065 on: November 21, 2016, 05:16:44 AM »
I'd like to second what SH said above regarding BFTV's contributions. Much appreciated!

liefde

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Re: 2016 sea ice area and extent data
« Reply #1066 on: November 22, 2016, 12:25:33 PM »
Chiming in here with a few facts I did not see mention often;

- An icey object floating will melt faster per m2 when its size is smaller, obviously, a logical result of having a larger contact ratio with (unfrozen) water. This is a problem, especially for polar ice-surface refreeze ('negative') energy requirements.

- Following that, looking at this:

we clearly see that even the Antarctic seas now have +3C SST anomalies to suffer from (with a 1961-1990 base). This has its direct impact on sea ice area and extent of course. (Last year this was not the case; The seas around the Antarctic were at or below the 1961-1990 base.) As long as that's visible, we will see more melt than we would like to see.

Although not much of it is known, aside from the warmer oceans and undercurrents, I also think the big change in the thus-far stable QBO phases plays a big role here;
showing Sam Lilo's work here to make it clearer
It's unclear what is the source there, and it may not even be a warming globe or greenhouse effects for all of these, but it surely influences the distribution of air around the different layers in the atmosphere.

I don't think the global melting of ice in the same year is a coincidence there. You can even see the 2016 deviation in Wipneus' GSIA graph just about takes off when the QBO was done going out of phase, around mid May.

BornFromTheVoid

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Re: 2016 sea ice area and extent data
« Reply #1067 on: November 27, 2016, 03:16:02 PM »
Update for the week to November 26th

The current 5 day trailing average is on 9,199,000km2 while the 1 day extent is at 9,530,000km2.

(All the following data is based on a trailing 5 day average)
The daily anomaly (compared to 81-10) is at -2,061,000km2, a decrease from -2,166,000km2 last week. The anomaly compared to the 07, 11 and 12 average is at -1,134,000km2, an increase from -1,114,000km2 last week. We're currently lowest on record, the same as last week.



The average daily change over the last 7 days was +80.8k/day, compared to the long term average of +65.8k/day, and the 07, 11 and 12 average of +83.6k/day.
The average long term change over the next week is +83.5k/day, with the 07, 11, and 12 average being +81.6k/day.



The extent increase so far this November is the 7th largest on record. To achieve the largest increase, a gain of at least 193.0k/day is required (at least +220.4k/day with with single day values), while the smallest increase requires a loss of at least -227.8k/day (more than 620.9k/day with single day values) and an average increase requires a loss of 10.1k/day (185.8k/day with single day values).


BornFromTheVoid

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Re: 2016 sea ice area and extent data
« Reply #1068 on: December 04, 2016, 03:59:32 PM »
Update for the week to December 3rd

The current 5 day trailing average is on 10,130,000km2 while the 1 day extent is at 10,364,000km2.

(All the following data is based on a trailing 5 day average)
The daily anomaly (compared to 81-10) is at -1,715,000km2, a decrease from -2,061,000km2 last week. The anomaly compared to the 07, 11 and 12 average is at -774,000km2, a decrease from -1,134,000km2 last week. We're currently lowest on record, the same as last week.



The average daily change over the last 7 days was +133.0k/day, compared to the long term average of +83.5k/day, and the 07, 11 and 12 average of +81.6k/day.
The average long term change over the next week is +80.2k/day, with the 07, 11, and 12 average being +97.6k/day.



The extent increase so far this December is the largest on record. To achieve the largest increase, a gain of at least 87.2k/day is required (at least +84.8k/day with with single day values), while the smallest increase requires a gain of less than 36.4k/day (less than 30.2k/day with single day values) and an average increase requires a gain of 56.2k/day (51.5k/day with single day values).



The extent change in November was the 2nd largest on record, while the average extent was the lowest on record.




BornFromTheVoid

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Re: 2016 sea ice area and extent data
« Reply #1069 on: December 11, 2016, 11:28:53 PM »
Update for the week to December 10th

The current 5 day trailing average is on 10,747,000km2 while the 1 day extent is at 11,046,000km2.

(All the following data is based on a trailing 5 day average)
The daily anomaly (compared to 81-10) is at -1,659,000km2, a decrease from -1,715,000km2 last week. The anomaly compared to the 07, 11 and 12 average is at -841,000km2, an increase from -774,000km2 last week. We're currently lowest on record, the same as last week.



The average daily change over the last 7 days was +88.2k/day, compared to the long term average of +80.2k/day, and the 07, 11 and 12 average of +97.6k/day.
The average long term change over the next week is +71.8k/day, with the 07, 11, and 12 average being +67.8k/day.



The extent increase so far this December is the 6th largest on record. To achieve the largest increase, a gain of at least 86.9k/day is required (at least +80.2k/day with with single day values), while the smallest increase requires a gain of less than 19.1k/day (less than 5.4k/day with single day values) and an average increase requires a gain of 45.6k/day (34.6k/day with single day values).


BornFromTheVoid

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Re: 2016 sea ice area and extent data
« Reply #1070 on: December 19, 2016, 01:46:24 AM »
Update for the week to December 17th

The current 5 day trailing average is on 11,582,000km2 while the 1 day extent is at 11,762,000km2.

(All the following data is based on a trailing 5 day average)
The daily anomaly (compared to 81-10) is at -1,261,000km2, a decrease from -1,659,000km2 last week. The anomaly compared to the 07, 11 and 12 average is at -397,000km2, a decrease from -841,000km2 last week. We're currently lowest on record, the same as last week.



The average daily change over the last 7 days was +119.3k/day, compared to the long term average of +71.8k/day, and the 07, 11 and 12 average of +67.8k/day.
The average long term change over the next week is +56.4k/day, with the 07, 11, and 12 average being +76.1k/day.



The extent increase so far this December is the largest on record. To achieve the largest increase, a gain of at least 70.5k/day is required (at least +67.4k/day with with single day values), while the smallest increase requires a loss of more than 31.0k/day (more than 51.1k/day with single day values) and an average increase requires a gain of 8.7k/day (loss of 4.9k/day with single day values).


Tor Bejnar

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Re: 2016 sea ice area and extent data
« Reply #1071 on: December 19, 2016, 02:24:43 AM »
Thank you BFTV; I've been waiting impatiently for this report. (It's not like I couldn't predict when it would be posted, but I've been impatient for 2 days.)
Arctic ice is healthy for children and other living things.

Wipneus

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Re: 2016 sea ice area and extent data
« Reply #1072 on: December 22, 2016, 03:00:05 PM »
NSIDC extent: -148k.

A one and a half century drop in winter looks like this:

Buddy

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Re: 2016 sea ice area and extent data
« Reply #1073 on: December 22, 2016, 03:22:10 PM »
Quote
A one and a half century drop in winter looks like this:

That Atlantic side sure is toasty....
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Juan C. García

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Re: 2016 sea ice area and extent data
« Reply #1074 on: December 22, 2016, 03:49:53 PM »
Quote
A one and a half century drop in winter looks like this:

That Atlantic side sure is toasty....

With this drop, seems that in NSIDC, 2016 will have low daily records on more than 50% of the days. Only 10 more days to accomplish the 50+% days of low records on the 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.

BornFromTheVoid

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Re: 2016 sea ice area and extent data
« Reply #1075 on: December 25, 2016, 02:58:44 PM »
Update for the week to December 24th

The current 5 day trailing average is on 11,866,000km2 while the 1 day extent is at 11,847,000km2.

(All the following data is based on a trailing 5 day average)
The daily anomaly (compared to 81-10) is at -1,372,000km2, an increase from -1,261,000km2 last week. The anomaly compared to the 07, 11 and 12 average is at -645,000km2, an increase from -397,000km2 last week. We're currently lowest on record, the same as last week.



The average daily change over the last 7 days was +40.6k/day, compared to the long term average of +56.4k/day, and the 07, 11 and 12 average of +76.1k/day.
The average long term change over the next week is +44.2k/day, with the 07, 11, and 12 average being +61.2k/day.



The extent increase so far this December is the 2nd largest on record. To achieve the largest increase, a gain of at least 100.5k/day is required (at least +44.8k/day with with single day values), while the smallest increase requires a loss of more than 102.5k/day (more than 139.8k/day with single day values) and an average increase requires a loss of 23.2k/day (loss of 25.8k/day with single day values).


Tor Bejnar

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Re: 2016 sea ice area and extent data
« Reply #1076 on: December 25, 2016, 11:21:57 PM »
"and an average [December] increase requires a loss of 23.2k/day (loss of 25.8k/day with single day values)."
Although this is achievable, I don't expect it.
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bbr2314

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Re: 2016 sea ice area and extent data
« Reply #1077 on: December 27, 2016, 01:14:15 AM »
is this an error on HYCOM??? look at NATL/Arctic...




Andre

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Re: 2016 sea ice area and extent data
« Reply #1078 on: December 27, 2016, 03:34:20 AM »
@bbr: maybe its just me but your posted images arent loading for me.

bbr2314

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Re: 2016 sea ice area and extent data
« Reply #1079 on: December 27, 2016, 03:56:48 AM »
@bbr: maybe its just me but your posted images arent loading for me.
they are from a NAVY site and i had to forego an insecure browser connection to view them so perhaps ye must all do the same?

at link:

https://www7320.nrlssc.navy.mil/hycomARC/arctic.html

Tigertown

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Re: 2016 sea ice area and extent data
« Reply #1080 on: December 27, 2016, 04:07:47 AM »
I can see them just fine.Maybe software limitations. Phone or notebook or laptop?

Zantage

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Re: 2016 sea ice area and extent data
« Reply #1081 on: December 27, 2016, 04:45:14 AM »
The "security certificate" doesn't match the website URL, so browsers set at what is generally considered typical levels of security won't see them without an override. If you see them, your browser is set fairly "loose" from a security perspective.

budmantis

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Re: 2016 sea ice area and extent data
« Reply #1082 on: December 27, 2016, 05:59:03 AM »
I've got a laptop and I can see them as well. Strange to see open water above 80 degrees North in late December.

Jim Hunt

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Re: 2016 sea ice area and extent data
« Reply #1083 on: December 27, 2016, 12:31:34 PM »
is this an error on HYCOM??? look at NATL/Arctic...

Is it an error if AMSR2 shows it too?
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FishOutofWater

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Re: 2016 sea ice area and extent data
« Reply #1084 on: December 27, 2016, 06:20:44 PM »
To make matters even worse, the flow of ice out through the Fram Strait has been maxing while the warm Atlantic water has been pushing the ice back to 80º N on the Siberian side. Warm water in and thick ice out means that thickness will be at record lows for the end of December. PIOMAS is going to be ugly.

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Re: 2016 sea ice area and extent data
« Reply #1085 on: December 27, 2016, 08:12:51 PM »
is this an error on HYCOM??? look at NATL/Arctic...

No error, bbr; the recent weather *DID* melt/push back all the ice around FJL.
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Buddy

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Re: 2016 sea ice area and extent data
« Reply #1086 on: December 27, 2016, 09:09:41 PM »
Quote
Is it an error if AMSR2 shows it too?

It sure looks like the Atlantic is going to be "feasting" on ice this coming spring...summer...and next fall.

Not good.......

Too many things are "lining up"....and they are NOT good things...

« Last Edit: December 27, 2016, 10:11:49 PM by Buddy »
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Shared Humanity

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Re: 2016 sea ice area and extent data
« Reply #1087 on: April 09, 2017, 03:28:22 PM »
The problem is that area is not increasing. The "increases" are clouds or interference of whatever type. Clearly, the Kara is completely ice-free and 15K KM2 of ice did not spontaneously appear along its shorelines. It is just noise and the gains should not be interpreted as legitimate (at least not until we hit minimum).

The thing is, scientists use data. They don't simply dismiss out of hand those they don't like because numbers disagree with what they think or feel they should be. At the end of the season, we can't look at any of the metrics and say, "I don't care what PIOMAS, or IJIS, or NSIDC, or anyone else says; they were all just measuring 'clouds or interference', so the official numbers 'should not be interpreted as legitimate'."

Absolutely, the measures we have (so long as the yardstick doesn't change which is why I'm also concerned by the shift in SIE measurement) are accurately capturing the trends in the ice and while clouds or whatever may obscure a daily number, they do not cause any real disturbance in the metrics.