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johnm33

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Re: The 2018/2019 freezing season
« Reply #1000 on: January 12, 2019, 12:00:15 AM »
agreed, it happened just as the storm passed north so I suspect ice driven by wind or windrows of ice in the troughs of the waves.

SimonF92

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Re: The 2018/2019 freezing season
« Reply #1001 on: January 12, 2019, 12:45:18 AM »
Shame, would have spurred some interesting reading had it happened.

Forgive my naivety.

Neven

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Re: The 2018/2019 freezing season
« Reply #1002 on: January 12, 2019, 10:32:23 AM »
Well, we've seen oddener things happen.  ;)
Il faut comparer, comparer, comparer, et cultiver notre jardin

uniquorn

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Re: The 2018/2019 freezing season
« Reply #1003 on: January 12, 2019, 12:26:43 PM »
Shame, would have spurred some interesting reading had it happened.

Forgive my naivety.
thanks for the research  :)  It's unlikely that this year's mostly first year ice is up to the job. Waves are over 3m today, forecast for over 4m tomorrow.
polarview, Greenland ice front closest to Jan Mayen, jan12 
« Last Edit: January 12, 2019, 02:02:45 PM by uniquorn »

litesong

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Re: The 2018/2019 freezing season
« Reply #1004 on: January 12, 2019, 07:29:32 PM »
Here's a "ho hum" news article on the first -50degF weather system(spot temperature, -51.7degF) in Alaska for the winter season:
http://cimss.ssec.wisc.edu/goes/blog/archives/31275

Contrasting a continental "far north cold" U.S. state, Maine had its coldest ever temp recorded in mid-January 2009 of....... -50degF.
« Last Edit: January 12, 2019, 07:38:21 PM by litesong »

Jim Hunt

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Re: The 2018/2019 freezing season
« Reply #1005 on: January 12, 2019, 07:35:19 PM »
In the continuing absence of the PIOMAS numbers, here's my own take on the current state of the sea ice in the Arctic:

http://GreatWhiteCon.info/2019/01/facts-about-the-arctic-in-january-2019/

Quote
According to The Economist today:

"America’s government shutdown has become the longest in history. Hundreds of thousands of federal workers remain either stuck at home or forced to work without pay."

and according to the Polar Science Center at the University of Washington:

"Due to the US Government Shutdown, PIOMAS ice volume and thickness data which depend on federal government generated reanalysis products, are currently not updated."

Plus another blast from the past courtesy of the Russian Arctic and Antarctic Research Institute, where everybody still appears to be hard at work. Note that there's no sign of the Odden Ice Tongue on any of those maps!

Reality is merely an illusion, albeit a very persistent one - Albert Einstein

meddoc

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Re: The 2018/2019 freezing season
« Reply #1006 on: January 13, 2019, 01:34:11 PM »
The Vortex is Toast...
Get Ready for a Scorcher as soon as the Sun comes back.

Jim Hunt

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Re: The 2018/2019 freezing season
« Reply #1007 on: January 13, 2019, 03:33:04 PM »
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

Shared Humanity

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Re: The 2018/2019 freezing season
« Reply #1008 on: January 13, 2019, 04:49:27 PM »

Aluminium

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Re: The 2018/2019 freezing season
« Reply #1009 on: January 14, 2019, 07:48:34 AM »
January 6-13.

Sterks

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Re: The 2018/2019 freezing season
« Reply #1010 on: January 14, 2019, 08:00:03 AM »
The combination of the strong Arctic HP and the Atlantic storm caused that receding of the ice in Barents. Negative AO, potentially very negative excursion predicted for next week, might keep ice edge expansion slow...

binntho

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Re: The 2018/2019 freezing season
« Reply #1011 on: January 15, 2019, 07:08:55 AM »
Article on the Polar Vortex split - Europe is in the freezer, but what will happen in the Arctic? I don't know if it's only an illusion but I tend to think that, just as there is a finite amount of warmth in the atmosphere at any given time, so there should also be a finite amount of "coldth" and if a big blob of coldness slips into Europe, another blob of warmth should be going to where that coldness is not. Or is that just rubbish?

binntho

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Re: The 2018/2019 freezing season
« Reply #1012 on: January 15, 2019, 07:28:36 AM »
Just bumped into another one, this time from the  main Italian forecaster. For those who don't read Italian, the main points are: "Polar vortex in pieces" is the caption plastered across the image, and further down: "Looking at the analysis map one notices that the coming days will see a very strong warming of the stratosphere, one of the strongest of the last 30 years, on par with or stronger than the one in 1985, in fact canging from -75 to -10 degrees, a crazy jump in temperatures of 65 degrees."

uniquorn

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Re: The 2018/2019 freezing season
« Reply #1013 on: January 15, 2019, 12:21:58 PM »
January 6-13.
Not sure what makes amsr2 detect large floes as lower concentration than the 'glue ice' in between. Snowdrifts?
With the cold wind, I'd expected the ice to cross the warm current to Svalbard again but no, it still melts.
amsr2-uhh, atlantic front, jan7-14
worldview, viirs, bt15n, atlantic front, jan15  https://go.nasa.gov/2FvSg66

gerontocrat

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Re: The 2018/2019 freezing season
« Reply #1014 on: January 15, 2019, 07:14:02 PM »
Just bumped into another one, this time from the  main Italian forecaster. For those who don't read Italian, the main points are: "Polar vortex in pieces" is the caption plastered across the image, and further down: "Looking at the analysis map one notices that the coming days will see a very strong warming of the stratosphere, one of the strongest of the last 30 years, on par with or stronger than the one in 1985, in fact canging from -75 to -10 degrees, a crazy jump in temperatures of 65 degrees."
Google translate does very well with Italian. It seems the Italians are saying that the SSW that has just happened is likely to be followed with an even stronger one. I shall be keeping an eye on this from http://ds.data.jma.go.jp/tcc/tcc/products/clisys/STRAT/ (a website of the Japan meteorology agency).

If this means the Polar Vortex falls to bits and Eastern USA, Central Europe and part of Siberia are to be clobbered over the next few weeks what does this mean for the Arctic for the remainder of this freezing season?

Current images attached.

ps: An example of the upside of globalisation. Scientists and Government agencies all over the world working together to provide the pieces of the jigsaw of the complete climate and weather fabric. Something that the Trumps of the world just do not comprehend.
"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)

binntho

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Re: The 2018/2019 freezing season
« Reply #1015 on: January 16, 2019, 07:12:29 AM »

Google translate does very well with Italian. It seems the Italians are saying that the SSW that has just happened is likely to be followed with an even stronger one. I shall be keeping an eye on this from http://ds.data.jma.go.jp/tcc/tcc/products/clisys/STRAT/ (a website of the Japan meteorology agency).

Well the Italians seem to be saying just that in this article from yesterday. To quote: "In fact, a second important stratospheric warming has started on the Siberian area, causing a new weakening of the polar vortex, [which is] now in deep trouble".

Niall Dollard

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Re: The 2018/2019 freezing season
« Reply #1016 on: January 16, 2019, 08:14:26 AM »
Current ECMWF op run, which stretches out to Jan 26th, shows no northern blocking over the North Atlantic.

For western Europe, going by these charts, the impact of the late December SSW is quite minimal.

binntho

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Re: The 2018/2019 freezing season
« Reply #1017 on: January 16, 2019, 09:07:17 AM »
Current ECMWF op run, which stretches out to Jan 26th, shows no northern blocking over the North Atlantic.

For western Europe, going by these charts, the impact of the late December SSW is quite minimal.
Not that I know the first thing about SSW but the weather in Europe has been pretty wild these last few weeks, with extreme cold reaching all the way down to North Africa, massive amounts of snow in the Alps and elsewhere in central/western Europe, while Iceland had temperatures that would have been more normal in summer than winter, with practically no snow (although that has changed drastically in the last few days).

El Cid

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Re: The 2018/2019 freezing season
« Reply #1018 on: January 16, 2019, 10:05:34 AM »
I wrote about the upcoming SSW in December in this thread, you could see it very early on the GFS 10hpa temp charts by then, but it has already happened. Now, however, GFS shows the polar vortex gradually going back to normal by day 10 from now, no hit from Siberia, or anywhere else. The vortex seems to be centered above the CAA by day 10.

see it here:

http://www.wetterzentrale.de/en/topkarten.php?map=2&model=gfs&var=42&run=0&time=0&lid=OP&h=0&mv=0&tr=24#mapref


I agree with Niall, no serious hit so far from the vortex collapse, no severe weather seen the next 10-14 days, at least not in Europe. There is however an outbreak of pretty cold air over NE USA starting T+4 / T+5.

binntho

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Re: The 2018/2019 freezing season
« Reply #1019 on: January 16, 2019, 10:32:21 AM »
Not sure what the Italians have been smoking - they talk about 10 degrees Centigrade below average after the 20th, and refer to GFS and ECMWF. I don't see it myself, although GFS has some pretty mean temperatures after the 26th but that's too far ahead to rely on.

But the website severe-weather.eu is also predicting freezing temps after the 20th. Who to believe ...

colchonero

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Re: The 2018/2019 freezing season
« Reply #1020 on: January 16, 2019, 11:23:04 AM »
Current ECMWF op run, which stretches out to Jan 26th, shows no northern blocking over the North Atlantic.

For western Europe, going by these charts, the impact of the late December SSW is quite minimal.
Not that I know the first thing about SSW but the weather in Europe has been pretty wild these last few weeks, with extreme cold reaching all the way down to North Africa, massive amounts of snow in the Alps and elsewhere in central/western Europe, while Iceland had temperatures that would have been more normal in summer than winter, with practically no snow (although that has changed drastically in the last few days).
Actually, the weather has been warmer than average in central Europe this Winter until now. On the other hand, there were cold outbreaks in eastern Europe, with solid amounts of snow all the way down (not just mountains and hills) multiple times.



BTW, after day 5 EC suggests cold may return over Bering, stay over Baffin and Kara, while Atlantic front and especially Okhotsk should see some +ve anomalies.
« Last Edit: January 16, 2019, 11:35:47 AM by colchonero »

uniquorn

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Re: The 2018/2019 freezing season
« Reply #1021 on: January 16, 2019, 02:27:37 PM »
A further look at the amsr2 representation of ice on the atlantic front over the last few days where refrozen fractures show as higher concentration than older floes. This is apparent on both uni Hamburg and Bremen.
Comparing with worldview viirs, brightness temperature(band 15,night) with different palettes (green1 and rainbow1) there is a haze above the refrozen fractures, more visible on the rainbow palette. Perhaps it is mist due to heat escaping through the thinner ice. Snow would be unlikely where the ice meets the ocean.
worldview,viirs,bt15n,jan16  https://go.nasa.gov/2TWCNzh
amsr2-uhh, jan15 - high contrast on right

edit: added polarview image for reference, nw of FJL, jan18
« Last Edit: January 18, 2019, 04:22:53 PM by uniquorn »

FishOutofWater

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Re: The 2018/2019 freezing season
« Reply #1022 on: January 16, 2019, 06:52:03 PM »
FYI, the ECMWF and GFS models saw the SSW coming although they have been struggling with the details on how the deceleration of the vortex in the high stratosphere would work its way down in the atmosphere. I have been surprised about how well the CFS model has done at getting the big picture right about the SSW beginning to affect surface weather strongly around January 15.

I wrote about the developing SSW on 19Dec18.
https://www.dailykos.com/stories/2018/12/19/1820257/-Thirty-Mile-High-Wave-Encircling-Earth-to-Break-over-North-Pole-on-Christmas-Day

RoxTheGeologist

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meddoc

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Re: The 2018/2019 freezing season
« Reply #1026 on: January 17, 2019, 11:35:14 AM »
<snip, no nonsense, please; N.>
« Last Edit: January 17, 2019, 12:03:36 PM by Neven »

b_lumenkraft

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Re: The 2018/2019 freezing season
« Reply #1027 on: January 17, 2019, 11:57:26 AM »

Leave that Politics Sh*t out of it.


What?? :o

I think you clicked the wrong button.

uniquorn

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Re: The 2018/2019 freezing season
« Reply #1028 on: January 17, 2019, 04:57:26 PM »
Beaufort working up quite a spin over the last two weeks.
Worldview viirs, bt15n, jan4-17  (3.3MB)  https://go.nasa.gov/2TTrPdG

Sterks

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Re: The 2018/2019 freezing season
« Reply #1029 on: January 18, 2019, 08:43:57 AM »
All cracked and leaking, a pity we can't see it in visible light. Thanks Uniquorn.

Juan C. García

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Re: The 2018/2019 freezing season
« Reply #1030 on: January 18, 2019, 02:27:28 PM »
All cracked and leaking, a pity we can't see it in visible light. Thanks Uniquorn.


The lesson of cracks on February 2013 is that early cracks allow the ocean heat to be released. After the ocean losed the heat, there is  still time to have a refreeze. So, these cracks can end with an ice that will be more persistant on spring and summer.

We will have to wait and see.
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.

colchonero

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Re: The 2018/2019 freezing season
« Reply #1031 on: January 18, 2019, 10:37:25 PM »
A bit off topic, and I may sound like bbr, but I need to ask. Has anyone seen new EC run for the USA. What a run!!  There is a -28C negative anomaly, and -28C temp 850hPa, as far south as Huntsville AL. For people in Europe reading this, that's much further south than Athens or Gibraltar (38vs36vs34 latitude degrees).  And I'm confident by looking at how large the sub -28C field is, there is even colder air in the middle of it (Minnesota for example), but EC "range" (on meteociel at least) stretches only to -28C.




GFS 12z has greater than -20C anomaly over Hudson in the middle of Winter, and -40C temp850hPa on US-Canada border.



I'm sorry for many photos and a long post, but this really may be 1 in a decade night ( both models have some ridiculous numbers at the same time, especially EC because it's so far south)

I'm posting now, because obviously I don't think it will come true.

Thomas Barlow

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Re: The 2018/2019 freezing season
« Reply #1032 on: January 19, 2019, 02:22:31 AM »
To give a rough visualization and compare areas (extent) I took out
< 1.5 metre ice from 17 Jan. 2018 and 17 Jan. 2019, to compare to all ice (thickness map is usually very roughly similar visually to extent map in area), mid Sept. 2018.

http://polarportal.dk/fileadmin/polarportal/sea/CICE_combine_thick_SM_EN_20190117.png
« Last Edit: January 19, 2019, 02:46:11 AM by Thomas Barlow »

Aluminium

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Re: The 2018/2019 freezing season
« Reply #1033 on: January 19, 2019, 08:34:16 AM »
January 11-18.

El Cid

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Re: The 2018/2019 freezing season
« Reply #1034 on: January 19, 2019, 10:30:57 AM »
A bit off topic, and I may sound like bbr, but I need to ask. Has anyone seen new EC run for the USA. What a run!!

I wrote about it on the 16th: "There is however an outbreak of pretty cold air over NE USA starting T+4 / T+5.".

Cold outbreaks like this - as far as I know - are not that uncommon in the US. Surface temperatures eg. in Chicago are set to hit next week -18 C, but as the winter record is -32 C and the mean winter minimum is -23 C, it is not much to talk about.
Same stands for Huntsville, Alabama that you mentioned. Don't make the mistake of comparing it tho Athens, or Gibraltar, as Huntsville's record low is -24 C, very-very far from what Athens ever experienced. The winter climate in the US (midwest and East) is very very different from Europe

Shared Humanity

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Re: The 2018/2019 freezing season
« Reply #1035 on: January 19, 2019, 03:02:35 PM »
Cold outbreaks like this - as far as I know - are not that uncommon in the US. Surface temperatures eg. in Chicago are set to hit next week -18 C, but as the winter record is -32 C and the mean winter minimum is -23 C, it is not much to talk about.

Yep. It's called winter and this is the 1st real winter weather we have had this year. We look to be getting 8 inches of snow in Chicago and we may actually see lows fall below zero a couple of times over the next 10 days. Of course, below zero temps were a regular occurrence in the 80's.

That's freedom degrees, not commie degrees.  ;)

meddoc

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Re: The 2018/2019 freezing season
« Reply #1036 on: January 19, 2019, 03:17:25 PM »
Cold outbreaks like this - as far as I know - are not that uncommon in the US. Surface temperatures eg. in Chicago are set to hit next week -18 C, but as the winter record is -32 C and the mean winter minimum is -23 C, it is not much to talk about.

Yep. It's called winter and this is the 1st real winter weather we have had this year. We look to be getting 8 inches of snow in Chicago and we may actually see lows fall below zero a couple of times over the next 10 days. Of course, below zero temps were a regular occurrence in the 80's.

That's freedom degrees, not commie degrees.  ;)

It's long not been Winter, only Cold Outbreaks from the multmillion year Arctic Fridge.

If You can't comprehend that, given all Satellite & etc Data
-go Vegan;)

FredBear

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Re: The 2018/2019 freezing season
« Reply #1037 on: January 19, 2019, 03:45:57 PM »
Off Topic!

I like oC - it's so easy:-
100  = boiling
25+ = hot
20    = comfortable
10    = warm winter day/ cool night
0      = freezing (as is any lower temperature)
Works well in UK!

Those that stick to oF (like my wife!) miss out on the scientific benefits of decimal systems too.

Alexander555

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Re: The 2018/2019 freezing season
« Reply #1038 on: January 19, 2019, 05:23:22 PM »
A new record is not far away.

El Cid

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Re: The 2018/2019 freezing season
« Reply #1039 on: January 19, 2019, 05:51:33 PM »
It's getting a bit OT, but I would advise against using all these fancy sites like ventusky for forecasting weather, when you have the world's unquestionably best model, the ECMWF and its forecasts at your fingertips, eg here for Chicago:

https://weather.us/forecast/4887398-chicago/ensemble/euro

Also, it is my experience that when the main (operational) run is far from the ensemble mean, it is usually the ensemble mean that you need to consider as the most likely scenario. And of course anything beyond 5-7 days is fantasyland as we all know. The ensemble mean goes to -5 F (cca -21 C) on Jan 26th which is cold but not so much when you consider Chicago climate averages

(it is also true for Arctic weather forecasts that is why it might not be so much OT)

Thomas Barlow

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Re: The 2018/2019 freezing season
« Reply #1040 on: January 19, 2019, 06:48:46 PM »
Here is a black and white version of my post above.
I think the fact that there was thick ice (>1.5m) conjoined to Siberia last year at this time, made a difference in the final outcome, with less open ocean in that region. I suppose thick ice could still grow there this year, but it took until about end of June before that thicker ice started to disconnect from Siberia last year. This year it should be pretty quickly far adrift from Siberia, early on, leaving a wider swathe of open ocean in that region, giving more solar heat and Ekman Flux (mixing depths to surface waters.)
•The top 2 show only >1.5 metre ice at this time of year (2018 and 19).
•The bottom one shows ALL ice from the same thickness map in mid-September 2018
« Last Edit: January 19, 2019, 07:03:54 PM by Thomas Barlow »

uniquorn

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Re: The 2018/2019 freezing season
« Reply #1041 on: January 20, 2019, 05:05:05 PM »
Here is a black and white version of my post above.
I found the colour one easier to understand and yes, a lot of older ice has been exported via the Fram Strait (or melted on the atlantic front before it got there). The Nares Strait is also still open.
We are increasingly dependant on the resilience of first year ice.
ascat, sep11-jan19, every 4 days (6.3MB)

The ice front approaches Svalbard again today.
polarview, jan20
« Last Edit: January 20, 2019, 06:07:26 PM by uniquorn »

johnm33

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Re: The 2018/2019 freezing season
« Reply #1042 on: January 20, 2019, 08:54:16 PM »
Nice animation,
I'm curious about the coherent wave structures that appear around the periphery, 2 by FJL, 5 near Svalbard, and numerous in Chukchi/Bering. Either signs of massive movements of water or artifacts of the data collection?
Day 274 for instance.

oren

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Re: The 2018/2019 freezing season
« Reply #1043 on: January 20, 2019, 10:42:20 PM »
Thank you uniquorn, I was aware that some thick old ice has rotated towards the Chukchi, and was hoping for a more resilient melting season. However, I was totally unaware that so much of that stuff has disappeared in the direction of the Atlantic. Quite scary, to be honest.

uniquorn

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Re: The 2018/2019 freezing season
« Reply #1044 on: January 21, 2019, 01:36:30 AM »
I'm curious about the coherent wave structures that appear around the periphery
I don't know, but I think the way the data is collected causes artifacts. There is a rotational pulse that runs through consecutive images related to how the swaths are put together. Artifacts are enhanced when attempting to draw out ice details. Here is an example of 2018 day298.
Default
contrast 31,255 and clahe 63,256,2.2
unsharp mask 1.0,0.6
The numbers are settings in ImageJ (which is really easy to use when you get used to it :)  and thanks to A-Team for helpful suggestions when getting started)
« Last Edit: January 21, 2019, 02:12:14 AM by uniquorn »

uniquorn

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Re: The 2018/2019 freezing season
« Reply #1045 on: January 21, 2019, 01:47:07 AM »
The lesson of cracks on February 2013 is that early cracks allow the ocean heat to be released. After the ocean losed the heat, there is  still time to have a refreeze. So, these cracks can end with an ice that will be more persistant on spring and summer.
We will have to wait and see.
The movement is quite similar, though I think there was significantly more MYI in 2013.
There is hope Oren ;)
ascat jan6-16, 2013 and 2019

Sterks

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Re: The 2018/2019 freezing season
« Reply #1046 on: January 21, 2019, 08:23:47 AM »
Seems to me the opposite, at least in the Beaufort. 2013 came after the big wipeout of 2012 so it was mostly FYI where the cracks appeared.
There's a nice barrier of MYI in the Beaufort like there wasn't since some time.

johnm33

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Re: The 2018/2019 freezing season
« Reply #1047 on: January 21, 2019, 11:39:52 AM »
Day 274

Looks like standing wave between FJL/NZ, Orthogonal wave structure in Bering[more or less parallel to both coastlines], Southbound waves towards Bering, and a powerful system moving west from Mackenzie bay. Nothing to see over land or ice.

uniquorn

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Re: The 2018/2019 freezing season
« Reply #1048 on: January 21, 2019, 05:54:57 PM »
Seems to me the opposite, at least in the Beaufort. 2013 came after the big wipeout of 2012 so it was mostly FYI where the cracks appeared.
There's a nice barrier of MYI in the Beaufort like there wasn't since some time.
ascat is good for tracking movement but not necessarily for estimating thickness (unless you already have a good idea how long it's been there).
The closest I could find for piomas, as a guide for thickness, is jan2013 and dec2018.
« Last Edit: January 21, 2019, 06:25:29 PM by uniquorn »

uniquorn

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Re: The 2018/2019 freezing season
« Reply #1049 on: January 21, 2019, 06:58:02 PM »
Day 274
<snip> Nothing to see over land or ice.
Not sure about that. They are visible over the thin ice in the Beaufort and over  eastern Svalbard. Since they are largely transient, I have treated them as background noise. Would love to be wrong though.