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Messages - OffTheGrid

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1
Arctic sea ice / Re: Freeform season chatter and light commentary
« on: October 30, 2020, 07:46:11 AM »
From Hycoms Ross sea charts we've got flows perhaps coming out under that shelf alone ofa ballpark estimate around 10% of the total mass of Antarctic ice sheet if they were steady for a year, averaging over the last month.
Surface water temps east of south Island NZ peaked at 22C two years ago. Now they are 5C.
It's been snowing on the hilltops around Rotorua central nth Island most nights, some days for two weeks. In early summer. Hasn't even in deep winter for years.

2
Arctic sea ice / Re: Freeform season chatter and light commentary
« on: October 30, 2020, 07:34:45 AM »
Haven't popped in since my last post, near a month ago, been frenetic. Especially with the Ross ice shelf and transAntarctic mountains, Ross Island, East antictic dome vulcanism.
You've snapped the effects of the
  Tsunamis and Joekulups in those buoy motions Unicorn, there were a series up to and above half a kilometer high barrelling out over where Scott and McMurdo bases used to be, around the new moon. They refocused in the Bering sea causing a surge over 1 million tons per second of the whole width of Bering strait at up to and above 3kmph, and off the Alaskan and Siberian shelves under the slush pack.
Heads up. There's a Volcanic blast just triggered another round.
Pic is one about three hours ago. Heard the boom here in Rotorua.
This one is 1 km high at time of shot. Probably 2 km ramping up the Ross Archipelago. May have lensed into pyramid field 4km from peaks to holes north of Ross Island.

3
Arctic sea ice / Re: The 2020 melting season
« on: October 02, 2020, 09:17:01 PM »
Sure Oren, I agree that would be ideal. Anyone can see this for themselves with the currents and temperatures settings on nullschool, Windy's wave and swell settings, the itp charts at https://www.whoi.edu/page.do?pid=20781

Though I love to present these hypothesis in Beautiful Animations, and have images to make them from, my laptop hours are limited it's setup in a house, and my amphious 6m x 2.2m 2m standing hight solar electric mobile home, while comfortable to live in and energy independent, and capable of going all day long at 10-39kmph without out even drawing battery power on a single 100w solar panel, is not yet a risk free environment for a computer. Especially in a supervolcano caldera in winter.
I have some twenty gigabytes of satellite imagery and volcanic gas surface concentration data to process into videos small enough to share before our next international Greenland Emergency videoconference in a
Others here have better infrastructure and image processing skills than me.
I have to prioritize. Marveling at the mayhem asi is displaying, though interelated is a distraction that is escapism and light relief from the far bigger and more dangerous problem that we are trying to develop a feasible technological response for blunting the damage to be rapidly deployed.
This forum is a valuable resource, and the many hours put   in in near-real-time analysis and presentation by the gurus here, and your level headed moderation are most appreciated, thank you all.

4
Arctic sea ice / Re: The 2020 melting season
« on: October 01, 2020, 07:45:55 PM »
If you look at the buoy status charts, eg drift speed and engineering charts, and the composite plots temp and salinity you can see that the less than 12hr Ekman turbine cycle is going at full noise on all Beaufort buoys. Also seems to have a ~4day slush puddle washing machine cycle overlayed. I think from the near zero buoy temp, and a rise in pressure at the microcat that 120 has melted out. It's been freaky watching the mixing down to over 200m that's visible in the Ekman resonances showing on the composite temp chart particularly. Since that wave event. The only reason there's still a surface shield is the ongoing melt and current flushing the bottom melt out from under the thicker blob off South CAA.
I'm stunned by this Ekman turbine resonance mixing phenomenons power it's quickly working to flatten the salinity curve. It's obviously tidally influenced but at about 1.5 hour shorter period it's obviously deriving mechanical energy that's phase leading, and beat harmonics are clear to see when the peaks and troughs add or cancel with the tidal cycles. Perhaps they set the size of the 4 day cycle larger slushpuddles full of 5.5 hour smaller ones
And maybe there's larger ones on a monthly tidal cycle. That they are embedded in.
There's much worse wave and wind events building right now.
Unlikely to improve.

5
Arctic sea ice / Re: The 2020 melting season
« on: September 27, 2020, 11:59:39 PM »
Yes, didn't mean to imply it's bust today. But it should have it's thickest fresh lid of the year right now.  Instability sets in as it starts to freeze and multiple mechanisms such as large over turnings, as muddy the composite plots as you point out, set in.   
Also in play are osmotic diffusion of salt upwards, freshwater downwards across the fresh/saline boundary, and algae blooms sinking, entraining fresh water, taking it down to mix with the salty stuff, and thermal conduction and radiation upwards into the shield of the heat in that summer water layer. Once there it will convect to surface.
All these processes have been steadily ratcheting up in mutually reinforcing mixing effects. And weakening the shield stability since the earliest Beaufort ITPs in 2005.
In TrekSpeak:
Shields are at 20% and worse still, they and structural reinforcement fields and the warp core are suffrin from wild an unpreductable instubilities since tha last exotic energy wave swept through the quadrant.
Ah dinae ken how the ship could survive another like it.

6
Arctic sea ice / Re: The 2020 melting season
« on: September 27, 2020, 08:55:27 PM »
I not sure how you could say that with a straight face Uni.
That "past buoy for comparison was only last year. When it was measuring 50+ m of fresh surface shield at this time of year. This year it's about 15m.

The heat content was never even half the current measurements in the top 100m from 120 and even more so 121. Measured as total degrees above freezing point of seawater x volume of parcels. And it's now centered at under 50m depth. Used to be over twice as deep.
121 is recording big pockets to surface above the scale of the chart. Those white blobs.
Every washing machine clockwise/anticlockwise cycle of those loosely bound slush puddles is an Ekman pumping/suction cycle mixing away the surface shield into the Halocline below. The Beaufort is covered with short 2 m waves from Bering to past 80 nth right out into the ice off CAA. Mixing the fresh away, as we speak. Pacific summer water incoming, was able to shelter under insulating ice in the Beaufort for longer than usual in spring, early summer, so has lost much less energy by evaporation and wind cooling. Hence the danger that 20g/ litre of salt expelled from seawater freezing on the surface can raise salinity of the surface shield at 2 psu per 10 litres. And mixing remove the rest.

7
Arctic sea ice / Re: The 2020 melting season
« on: September 27, 2020, 01:18:53 AM »
Oh jeez...
We've got two new itp buoys in the North Beaufort. The fresh surface layer is thin enough to be raised to the salinity of the over 100 m below it by brine released from less than half a meter of ice. The heat content in that 100m is enough to melt 3-4m of ice. Itp120  is on the NorEast edge of the last thick blob that's now pushed against the garlic press over high salinity and heat outflowing warm water.
The Halocline looks bust.

8
Arctic sea ice / Re: The 2020/2021 freezing season
« on: September 24, 2020, 08:55:16 AM »
Well. With Mosaic basically proving that the best piece of ice in the best position on the Atlantic side of the Lomonosov ridge LOST thickness on its entire transit from October to may, from 7m to 5m, through constant bottom melt, and never froze it's soggy core. And now that they can cruise at open water efficiency, from laptev to Fram north of 86 latitude, and never register any fresh freezable layer...
 There appears to be no such thing as a Arctic sea ice freezing season anymore in this half of the Arctic basin.
Therefore I suggest a poll to rename this forum the SiAlCa sea ice forum. Hopefully there will be a few years while those elements hydrated minerals can still stay cold enough to remain solid on those sectors polar seas. Unlike Venus.
Wry and somewhat twisted that this bad half joke may sound.

<To make such claims you need to point out the source. I am not aware of any such findings. O>

9
Arctic sea ice / Re: The 2020 melting season
« on: September 24, 2020, 12:19:30 AM »
For pitys sake! Can someone here with a pixel counter run it over Hycom seaice thickness charts, so we can get an unpoliticised best available actual estimate on volume trends? And currently very obviously the lowest ever minimum that we are approaching?
Many of the best brains have fled this forum out of exasperation about the constant petty defending of "Trumped" data.

10
Arctic sea ice / Re: MOSAiC news
« on: September 23, 2020, 11:40:55 PM »
I think you mean just north of 86 north old boy?
That slush pic in their wake was at 88.3 just after they left on the 20th btw.
I think the Cap'n thunk the kids needed a bit of a reality check by scaring them to think they were going to run head on into a Beaufort 9 storm front with wave and swell chaos in the shelf fragments and skyscraper sized  Bergs on the edge of the ice front.
Instead he has turned ninety degrees due West to run with it.
They've copped the force nine thunderstorm hot front on the butt. But so far have no idea what force 9 sea states near coasts look like. He may blood them with that experience in the next few days.
This auld Ships Cap'n do. Me bin coastal on sail in force twelve Gustin to 180kmph. And experienced the site of 100+ ft rolling breakers from one horizon to the other coming in from the southern ocean at 60 second period all day long. Wavelength some 3km and velocity over 200kmph in the deep where they spawned, the beasties!

11
Arctic sea ice / Re: The 2020 melting season
« on: September 20, 2020, 10:49:37 PM »
Well, Hycom certainly doesn't think the melting season is over. And with SSS at 31 a degree above melting point is the water temperature under Mosaic, 2 degrees whenever there is any winds. With what's forecast in the next two days, it's going to be very interesting. Btw that thick looking bit north of svalbard is a stream of icebergs from Greenland.
As usual, click the gifs.

12
Arctic sea ice / Re: The 2020 melting season
« on: September 19, 2020, 03:13:52 AM »
The crude piomas model <unsubstantiated dissing snipped>.
Hycom has not been falsified by any direct ice thickness measurement by human or buoy. We have about 25% of 2012 ice volume currently <warning: not true>, and far more near surface ocean heat with far thinner fresh surface barrier. It's basically inevitable that big storm activity will wreak havoc on what's left as continental temperatures drop, but Arctic ocean heat is unable to.

<Please make sure posts are fact-based. O>

13
Arctic sea ice / Re: MOSAiC news
« on: September 18, 2020, 08:37:02 PM »
Watch out Mosaic!

There's been 14 second swells of 0.2 m coming out on the ESAS, AFTER passing all the way from Fram, under them <reader beware, this is nonsense>. May be having the effect you point out on the floe motion ATeam.
Also outburst flushing from Greenland, which looks to be going through exponential runaway geothermal blowout <reader beware, nonsense>, has been launching submarine landslides that are shedding violent fresh upwellings, and possibly mini tsunami surges, which could look like standard tidal effects, since the subglacial outbursts occur primarily at high tides. <nonsense>
Their "pretty frost flowers" are sadly a symptom of large energy injection from water vapour condensing. Driving bottom melt.
Gotta click the stupid gif to see the 11m long period waves heading for them in a few days.

<Warnings added. Posts must be fact-based. O>

14
Very scary picture of the collapsed NE Greenland 2000+ sqkm basin thats up to a km deep behind these Glaciers. On the right the dark area is inland of the coastal ranges. Now islands with the calving front merging all the glaciers from north and ne Greenland into one downsloping, below sealevel front, over 200 km long.

15
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: September 06, 2020, 11:28:31 PM »
Mosaic say down from extent 3.5 yesterday to 3.4 today.
Where their data from?
Are NSIC and Jaxa just pr products for the masses now?

16
Arctic sea ice / Re: The 2020 melting season
« on: September 06, 2020, 11:19:32 PM »
Wind @ Surface + 3-hour Precipitation Accumulation for the last 72 hours and the next five days.

All that snow is gonna insulate the ice from freezing, isn't it? Will this become another positive feedback loop? More open water means more snow, means more open water and even more snow next year?
Probably not enough snow on the polar ice to matter much with insulating these days. But it may in Future years. It does nucleate ice cover that prevents heat loss and fresh water freezing on top releases latent heat to the floe that feeds bottom melt well after the surface is frozen. Especially if Its vapour thats condensing and freezing, which is more mass of water than the rain often.
Mostly Its rain so far. Though gfs is showing half the wind that Mosaic is right now, which probably means more rain too.

17
Arctic sea ice / Re: MOSAiC news
« on: September 06, 2020, 10:55:37 PM »
Got up to fifty kmph winds, with a rise of nearly a degree in temp in the last hour. Twice the windspeed gfs is claiming at 1000hpa or surface.
Raining it is suposed to be with above zero surface to 850 Siberian coast to near the pole.

18
Arctic sea ice / Re: The 2020 melting season
« on: September 04, 2020, 09:54:57 PM »
Wow. Extent down to 3.5 already, Mosaic hasn,t yet recorded water temp other than -1.5 water temp, or below seawater freezing point for the air in a week at the pole.
And storm season is about to begin with bells on. A month later than 2012, but with far more ocean heat, and a compressed pack of far thinner, weaker, and fragmented ice. Wind of less than 20kmph showing raising wavelets in todays fomo. This looks like the above zero surface to 900hpa high Moisture blasts off the Atlantic front Past the pole, coupling  phase change heat from condensing vapour on ice and sea, with rain, and vertical mixing of the water may be disasterous. All that dispersion too! Ramming the best blob thru the CAA, and the rest into killing seas.
Plenty of clouds and fog trapping in heat above.
Shame we are losing visuals. So easy for misleading by stats from questionable satellites.

19
Arctic sea ice / Re: MOSAiC news
« on: August 13, 2020, 09:32:45 PM »
Should be in helicopter range. Apologies for understated dark humour about "dramatic". Had no Idea at the time.:
https://forum.arctic-sea-ice.net/index.php/topic,400.msg280842.html#msg280842

20
The best S1 shots from 9th to 12th, dates and times in filenames.
It looks like there were two major outbursts, one on the tenth, one early on the twelfth.

21
 :( First two are back to front sorry. Full lake and aquifer about to burst on the 10th, the first shot.
Outbursts in action: rubbish resolution worldview.

9, 10, 11 Aug closeups.

22
9, 10, 11 Aug closeups.

23
The clearing of Jokel Bay and the calved icebergs is continuing behind the clouds, courtesy of Sentinel-1. Open water now visible in the innermost bay.
Click to animate.
Thanks
That fills in a couple of missing days, especially the tenth. Which seems before the main burst, visible clearly on Worldviews. Not sure how much went through and under the Melange field, or however many hundreds of meters thick it is but the flow over the top suggest it could have passed 1 million tonnes per second at peak.
The whole Melange field moved ,parts over 10km in 5 days up to the 6 August, and extended up the inland  lakes on the sides of the main ice sheet, by the worldviews on the 11th.
Cloudy on 12th unfortunately. Perhaps lots of local humidity.

24
Arctic sea ice / Re: MOSAiC news
« on: August 10, 2020, 11:02:34 PM »
I agree basal ice streams  mechanisms are ot here. The paper I read on bedrock melting due to the friction of stop start  ice streams in Antarctica was some twelve years ago. If binntho wants to learn on an appropriate thread what a layer of entrained boulders can do as it gouges his grooves in the bedrock when under the pressure of kilometers of ice and downstream elastic tensions are suddenly released, I am surprised he is so certain that such heat released by this friction can't melt rock. But will try to find the paper and post it there. The flash refreeze physics are what startled me.
More on topic..
The only submarine landslide down a canyons system caught in the act of a flush wave and the results studied:
"The tsunami following the 2016 Kaikoura earthquake was relatively small but it was still the most significant event in around 50 years. Being onsite at the time and in the following months, we were able to document changes to the seabed and it has revealed some exciting science,” Dr Mountjoy said.

“In January 2017, we surveyed down to 2000m and discovered that large areas of the Kaikoura Canyon have drastically changed. Sediment has been transported from the Kaikoura canyon at least 300km north to the deep ocean floor offshore Wairarapa. The earthquake shook loose a huge amount of mud from the canyon rim that then flowed down into the canyon channel. As it accelerated downslope, this material appears to have eroded deeply into the canyon floor and ignited into a critical condition we call ‘autosuspension’. Amazingly, in this condition, sediment can flow indefinitely across the ocean floor. We know the deep sea Hikurangi Channel is 1500km long and this flow may have travelled the full length of it. No one has ever directly observed this process before – it is an amazing opportunity.”
This relatively small event moved "well over 850 million tons" of subglacial debris from the south zelandian ice sheet collapse over 10ky bp down a two to five km wide canyon carving 20 to 50m extra depth in the bedrock channel.
Zelandia is very simular to Greenland after deglaciation, and this is probably the smallest of three primary submarine  canyons. All carved by Jökulhlaup as can be see bursting on a daily basis on worldview from Greenland.
As this one was triggered by a paltry few thousands tons of river sediment shaken off the top of shelf above canyon head, I cannot imagine this not being an ongoing process in the arctic daily, and larger, at present.
Deserves Its own thread too. But for those interested:
https://niwa.co.nz/news/kaikoura-earthquake-provides-world-first-insight-into-submarine-canyons

https://niwa.co.nz/news/kaikoura-earthquake-generated-huge-submarine-sediment-shift

https://niwa.co.nz/news/a-wave-of-hazard-research

Note the rubble sizes transported in hypersuspension hundreds of km, and the many canyon systems visible on bathometry that is much higher resolution than any publicly available for the arctic. Kaikoura is noticably not the originator of this canyon system, but pegasus off the previously ice covered submerged land to the southeast where perhaps six major outbursts channels can be seen from previous deglaciations.
Greenland Zelandia and west Antarctica are very simular continents, in different geologic periods due to current latitude and climate.
Click on bottom two files for before/ after shelf image of initiating landslide and animated zoom in on the 2500km extention of the glacial rubble carved channel out to the Louisville seamount chain.


25
Arctic sea ice / Re: MOSAiC news
« on: August 09, 2020, 04:32:51 AM »
I'm sorry, I should have been cleared, I ment the downstream flows down the underwater river canyons can be ninety percent rock, meaning everything from loess to large boulders, and Organic matter, etc. Some call them submarine lahars. Outbursts megafloods are called that because they peak at over a million tons per second.
Haven't heard of anyone getting published on what solids content the flows through the underground lakes and their connections contain, but Its quite visible them emerging from all the NE Greenland glaciers in recent weeks just on worldviews images. Often theres huge outflows and then sometimes  backsurges in the floes on the surface of the deep fiords, as the whole pulse goes through at the bottom. You can see sediment discolouring bursts at the calving  front up to fifty km wide sometimes but the big flow is shooting north from under the rapidly disintegrating ice shelf, with the fragments being whisked away by the entrained surface current. Theres a huge basin below sealevel plugged by those glaciers, and the hydraulic head on the basal lake system is the deep funnel lakes we see repeating in the same places an shapes for the last years over a km above.
Both theses and the big Siberian rivers with flood surges send pulses down the submarine canyons to the deep basins. Which in the Arctic are very much very poorly understood because they are thousands of different bodys of suffering salinities temperatures, dissolved mineral,
organic and fine suspended solids that mix poorly.
The comment about rock melting, this does happen under icestreams, so you'd get superheated steam along with the water expelled into the drainage system, before the runaway rate of melt causes a crash sudden quench and the base flash freezes to the bedrock again. Antarctic ice streams have been documented as pulsing forward at the base up to 100m at several meters per second in this fashion. Don't think Its known if this in sustained fashion occurs in these high speed glacier collapses elsewhere. But if either of these big ones, or the humbolt could that it would be dramatic, uncorking the whole pressurised interior lake system.
The bad news is the anoxic freshwater seeping out of those silt lahars in the deep basin has replaced the downwelling oxygen brine chimneys from lost Ice Shelves and multiyear ice keel that all those scientists were screaming about the direness would result from this loss ten or more years ago.

26
Arctic sea ice / Re: MOSAiC news
« on: August 06, 2020, 09:13:17 PM »
Polarsterns been sampling that eddy for precisely that reason. This looks like well over 20 gigatons of subglacial outbursts in the NW alone in the last few weeks. Not only are they heavy with up to 90% rock, capable of carving canyons over 1000 km out into deep ocean basins, but the surging of fast glaciers can melt the bedrock at 1500 C plus, so they can be very warm indeed.

27
Arctic sea ice / Re: MOSAiC news
« on: August 05, 2020, 09:50:36 PM »
Lots of sensors on this buoy. Reason it needed to do only one up/ down crawl per 3 days, causing the lumpy looking T/S plots btw.

28
Arctic sea ice / Re: MOSAiC news
« on: August 05, 2020, 09:42:11 PM »
Itp 94 deployed by the Mosaic campaign has finished Its run and returned some very disturbing readings. Dissolved oxygen at near zero for the whole Atlantic side transit. Dissolved and particulate organic matter, turbidity through the roof. I desperately hope the DO sensor was faulty. But it would explain why all the polar bears were way out on the Atlantic front.
Major high turbidity upwelling from well below 760m depths was detected out near the pole. Suspect that sediment and methane laden bottom freshwater flow from Laptev and/or 79N NE Greenland subglacial outbursts have busted the deep halocline stability out in the deep basin bringing up ex-hypersaline bottomwater mass from the deep basin. VERY scary. Our much appreciated contributer
 Veli albert kallio is the world acknowledged professional expert on this kind of thing. We've had discussions previously  about this sort of possibility, with Wadhams and other experts I work with involved. I'll get a conference going. We may have to look at urgent oxygen and salt restoratation in deep benthic Atlantic side of the Lomonosov.
Would be very helpful if Uniquorn can do one of his locations/date animations over bathometry so we can localise events clearly.

29
Arctic sea ice / Re: HYCOM
« on: August 04, 2020, 09:00:06 PM »
Unfortunate that Hycom has seemingly decided to censor the higher resolution Beaufort model. Its last run on the 24th of July looks like a darn good effort in advance of the accurate picture SMOS is presenting. Bearing in mind that the Soil Moisture/ Ocean Salinity sensor works on detecting the averages over a 40km square grid between the less salty ice surface and the horizon of slush soaked with seawater below.
Its low frequency radar sees straight through ice and water cloud, including fog. The maximum resolution of the higher frequency radars used by Jaxa, etc for their much more promoted extent and area metrics, is at the expense of being badly compromised by cloud effects. And they are still limited to about 500m resolution, so do not see open water below that breadth. A bigger and bigger problem in this season every year. Hycom is probably suffering from falling behind in the need to update algorithims to account for these rapidly crumbling models Its assimilating data from.
Ice crumbling to fields of dispersed slush is far different to solid sheets with crosshatchings of long leads.
Other than the Chukchi not getting the Beaufort arm shoved as far into it, and more ice surging into mckenzie bay from the CAA mega flow than Hycom predicted before the storm, good predictive skill I think. Backed up by what satellite visuals we've had through the clouds and fog.
Still have to click to animate the absurdly small smos gif.

30
Arctic sea ice / Re: HYCOM
« on: July 30, 2020, 04:58:58 AM »
For comparisons, piomass monthly Thickness averages July/ Aug 2014.

Reverend milkbones 29 July 2012, thickness, also from the previous arctic only Hycom model. Still looking for Pio2012

31
Arctic sea ice / Re: HYCOM
« on: July 30, 2020, 04:48:21 AM »
Here are todays concentration and thickness charts.
And the same day in 2014 which is the first year the arctic only model was replaced with the global model with weather and ocean data incorporated for prediction purposes.
Does my memory correctly recall that 2014 was the year piomass was updated for the last time? Along with a quiet media release forgotten or missed by most that they believed the piomass model had understated the 2012 minimum, and they revised it upwards?
I think this may be a little charitable for concentration in the central and coastal Beaufort, judging by worldviews.

32
Arctic sea ice / Re: The 2020 melting season
« on: July 30, 2020, 04:19:36 AM »
Sorry to ruin the party again but Hycom is thickness is not comparable between these years, the model has been changed several times since then, and 2012 has not been back-calculated.
BTW, DMI thickness is also not considered very reliable, again I would appreciate decreasing the frequency of posting it to the main thread.

Ah ok thanks for the info found a 2015 Hycom seems more compatible now they have fixed it, still a sucky year 2020. I Prefer data from small democratic socialist countries like Denmark and Finland, large democratic countries data is manipulated in a lot of cases it seems.

It could be argued that in a fast changing arctic, Its the models that are not updated that provide the poorest comparisons with past years. 2012 cleared out most of the years old hardened Ice. The sort capable of forming large pressure ridged fields. Unseasoned young ice, or waterlogged the previous summer is as little as ten percent as strong as fully brine excluded ice. The very rare legacy floe Mosaic used could be considered best case. May have spent many years hardning as fast Ice in the outer Siberian islands, yet the core of Its 7 m pressure ridge failed to fully freeze all winter.
On  about the best drift path it could have had.
 When they first picked it up it was waterlogged from base near to sealevel.
DMI is another example which seems to drift further from reality every year. Now showing up to three meter ice when the nearest has been slush hundreds of km further out to sea for weeks.

33
Arctic sea ice / Re: The 2020 melting season
« on: July 28, 2020, 08:54:24 AM »
July Arcus report now out https://www.arcus.org/sipn/sea-ice-outlook/2020/july

"Overall, the situation is little changed from the June report. There is a collective view that September ice extent will be reasonably close to the observed linear trend line, implying there will be no rapid decreases in Arctic sea-ice extent through the rest of the summer leading to a new record low."

Yes!
And also the adolescent, mum with two cubs, and lone male polar bears adored in last few weeks by the Mosaic PR writer will return from the dead!
 ???

34
Arctic sea ice / Re: The 2020 melting season
« on: July 28, 2020, 08:47:38 AM »

While we were all focussing on the storm, the north of Greenland has been roasting like a pig.
Yes. Foehn winds off Greenland and Elesmere have been fueling the storm, and expanding the megacrack. Last three day animation. Crick-crick!
Not only that, look at the SST anomaly in the Lincoln sea and west of Ellesmere.  ???
Is this a first?
Quite possibly. Especially for this time of year. South of Elsmere is even scarier with actual SST. Offshore winds over shelfdrops, when deep currents of warmer saltier stuff oppose will do this kind of thing.
Worse news? Those temps and anomalies are 42 hrs old. They only update every 4 days. Look out next update!

35
Arctic sea ice / Re: The 2020 melting season
« on: July 28, 2020, 08:27:28 AM »
Looking at whats up in the various atmospheric levels up to the tropopause, leaves me not so sure this cyclone is a short term visitor.

36
Arctic sea ice / Re: The 2020 melting season
« on: July 28, 2020, 08:19:27 AM »

While we were all focussing on the storm, the north of Greenland has been roasting like a pig.
Yes. Foehn winds off Greenland and Elesmere have been fueling the storm, and expanding the megacrack. Last three day animation. Crick-crick!

37
Arctic sea ice / Re: The 2020 melting season
« on: July 28, 2020, 07:44:15 AM »
969

Does this allow the cyclone to become one of the strongest summer cyclones? In recent years, only three cyclones dropped below 970, two in August 2012 and 2016, and one in June 2018?

Just going off latest data, don't know what past records are for GAC.
It is picking up see where it is later today!   :o

Something i had noticed on the NASA website about the 2012 cyclone, quote/ “Decades ago, a storm of the same magnitude would have been less likely to have as large an impact on the sea ice because the ice cover was thicker and more expansive,” Parkinson added.

NASA estimated, that there have only been about eight storms of similar strength during the month of August over the past 34 years of satellite records.

https://earthobservatory.nasa.gov/images/78812/2012-arctic-cyclone

So was wondering on the thickness of the ice in 2012 vs 2020. As thickness is becoming lower each decade, smaller storms and cyclones could do similar damage to larger storms/cyclones of the past? If 2012 had thicker ice than 2020 on July 28th would be interesting to see.
Absolutely.
Heres worldviews of the central Beaufort yesterday and day before, before the storm rolled in.
The gray areas further out are finely fragmented slush. Closer to the CAA, this slush shares ocean with big open area and what could be confused with large rounded stable looking floes.... Until you choose to go beyond the maximum resolution of worldviews, of 250m per pixel. On sentinel playground they are reveiled as loosly bound agglomgrations of various thickness, with big gaps of ocean all through them.

38
Arctic sea ice / Re: The 2020 melting season
« on: July 28, 2020, 07:30:19 AM »
Another view of that gap that has appeared near the pole. 
RAMMB contrast boosted.
Needs click

This illustrates very well a transition zone from ice weakly bound into a sheet moving in relatively uniform motion, to a region outside where Its sloshing around in an unglued slurry. Is it relief of compaction pressure? More likely that than any actual frozen glue ice holding the fragments together.

39
Arctic sea ice / Re: The 2020 melting season
« on: July 27, 2020, 09:35:28 PM »
Current wave conditions impacting the ice around the Beaufort cyclone. And peak wind and rain and temp as forecast by the Euro around min pressure at 6 to 9 hrs from now.  animate with clicking.
The waves of 2.3 from west and 1m swells from south conspire to produced grid of peaks 3.3 m above sealevel, and holes 3.3 below sealevel with distance about twenty metres over this 6.6m heights difference. An ice pulverising party, beginning right now off Barrow.
The peak winds and rain set to sever the Beaufort arm from the Outer CAA.
Also Hycom prediction for thickness and concentration in seven days after the storm has (will it???) passed. So we can scrutinise Its predictive skill in a week from now.

40
Arctic sea ice / Re: The 2020 melting season
« on: July 24, 2020, 11:32:07 AM »
The Beaufort is high extent because temps have been normal.
I don't think that's the only reason Friv. I think a slowdown of the gyre and thicker ice may have something to do with this as well. And then I saw the low sality...

But as you all know by now, I'm just a fat guy with a computer, so I'm gonna shut up now and leave it up to the specialists.  :-X
It certainly is not the reason. Clickon this animation of the last ten days of the furious pace of discharge from the central arctic sea into the Beaufort, both down the CAA coast, and also clearly visible the motion towards the Chukchi of the fragmented and low concentration central Beaufort.
The Irminger current historically used to turn south below Greenland and dip around Greenland before merging with the Labrador and heading south.
As pictured. Last ten years Its been turning south further north near Svalbard. Now last year, and even more this it has decided to go over the top of Greenland, and this year, not even satisfied by colonising the CAA, and Aided by the Beaufort clockwise gyre being closer to Mckenzie Bay,  it has stopped the Alaskan coastal current, heading east from Bering,  or at least pushed it under to flood the central Beaufort.
As you are seeing some is also going along the siberian coast.
It should be no surprise with this going on that the Beaufort, Chukchi and north of Greenland are about to catastrophically crash, along with the CAA. Particularly if the sub 980 low forecast in the Beaufort appears in a few days as forecast.
Click on Hycom thickness and concentration animations to see whats been and about to happen.

41
I think we are seeing serious far reaching consequences that may be attributed to these glaciers discharging dense silt laden freshwaters that avalanche down the seafloor to the deeps of the amundsun basin and gakkel trench system showing up in the ITP111 transect that has just been retrieved.
There are visible many small and one major upwellings of warm freshwater, and often very warm and saline entrained below or alongside, from far below the maximum depth range. From about the point the buoy crossed the gakkel in april, the halocline stability essentially collapsed with less than 0.5 psu separating surface and the huge wad of heat from ~100-500m depth. Some geothermal heat may have been brought up by this over the trench.
Its a little hard to wrap your head around whats going on in some of these spikes, but realising that 1000m rise in the water column of a parcel of water means 2.5C drop in temp due to expansion helps.
 
The buildup of subtropical Atlantic currents anticlockwise around Greenland, and even reading 33psu and over six degrees at surface as it exits from beneath the CAA ice is disturbing. Eric Rignot expressed surprise in detecting Atlantic water coming in from nares strait to the nth and attacking the base of the humbolt in the Kane basin on his sampling trip last year. He shouldn't have been surprised. This system change has been pretty obviously building for at least three years. People are witholding data unfortunately.
The catastrophic cascade collapse in the near Future of the GIS is not something many want to be heard talking about. 🙄

42
Arctic sea ice / Re: What the Buoys are telling
« on: July 19, 2020, 09:15:33 PM »
Oh what a wonderful surprise! After being missing in actions since January, ITP 111 has come home with a full profile along a very simular drift path to Mosaic.
Wow!!! No halocline whatsoever since march somewhere near the pole.

Contrasting with the other Atlantic side buoys, that stopped publishing profiles in january, same area, 102,  and 116 which quit on Jan 11. Same date as 117, 118, and 119 in the Beaufort. Just as they reached the upslope nth of the CAA (way too deep still for snagging the bottom, all.)

43
Arctic sea ice / Re: What the Buoys are telling
« on: July 17, 2020, 10:44:46 PM »
I follow the ITP dataset year after year. I have posted on an interesting decrease in the surface mixed layer, the salinity of which is variable depending on depth or season. There are no pycnocline layers the mixed layer. There are plenty of papers on the buildup of the surface layer and reasons why and there are also papers that postulate problems in the North Atlantic should a large amount of fresh water exit the Beaufort all at once.
 I can only watch some buoys and there are not many ITP buoys that survive the ice so we don’t have many to watch. If there are papers that discredit a buildup then please post them.
 I appreciate what FIshOutOfWater said about cyclonic winter conditions and a positive AO and the thinning I saw did occur during the winter months.
 I went through some effort to list buoys that had good runs in the Beaufort so other readers didn’t have to sort through failed buoy data. I would appreciate it OffTheGrid if you would cite some science rather than a curt , the paper is bullshit answer. Do you see the thinning I have pointed to and does it mean anything other than variability we should expect ? If you agree with me there has been a thinning perhaps you could enlighten me about where it has gone and point me to a dataset that documents your contention.

ps I noticed that the mixed layer in the Timmerman paper was for pacific inflow. I am just talking the surface fresh water layer that is deepest in the center of the gyre.
For what Its worth, my impression is that the freshest surface layer has thinned also. There have been papers discussed on this forum that  show increased halocline instability and an increase in overturning and mixing events in the Beaufort. The paper claiming an increase in freshwater content was also discussed. ATeam was one of those  who expressed disgust that they were defininging freshwater as anything below 34.5 psu, which is above the salinity of the increasing influx of pacific summer water through Bering. There has also been a big increase in shoaling of Atlantic water all down the outer CAA, some of which, even after full mixing and cooling with meltwater under ice through the entire CAA channel system is emerging at around 33 psu and 5C into the labrador.
Some of that shoaling water is also without any doubt going south and mixing with riverine and melt in shallow open waters in the Beaufort.
I have studied in depth all the itp historic profiles.the slopes of the recent salinity and temperature curves in the composite plots suggest increased instability of the protective Lid to my eye. I'll try find some examples later to post.
To be honest, I have lost confidence in their motives regarding what data they show us. Some six buoys have misteriously stopped publishing crawler profiles as soon as they get near the CAA in the last two years. Some as little as two months old. Given that it is undeniable that VERY warm Atlantic waters have formed a New major current system around the top of Greenland and south into the Beaufort and CAA, i smell coverup, wherther it is political, or academic gloryseekers withholding till they publish, it is the most important development in the arctic system in recent years imo.. AND btw should eliminate concerns of a cold fresh flush 1970s style.

44
Arctic sea ice / Re: What the Buoys are telling
« on: July 17, 2020, 02:18:28 PM »
FishOutOfWater, I posted on what I saw as a decrease in FWC of the Beaufort. It seemed like the surface fresh water layer got deeper over the years of watching the ITP buoys. From 2003 -2018 there was 40% more fresh water than in the seventies.
https://agupubs.onlinelibrary.wiley.com/doi/full/10.1029/2019JC015281

Which exit did the fresh water take and does this reduce the threat of a freshwater pulse entering the Atlantic or increase it?  I thought the buildup of FWC was considered a bit of a threat.

There is a big smelly rat in that paper that makes nonsense of any claims of an increase over that period.
"The total climatological (here defined to be prior to 1989) liquid freshwater content of the Arctic Ocean was estimated to be around 80,000 km3, relative to a reference salinity of 34.8"

We are now seeing Beaufort surface salinity in the 28 to 32 psu range. Prior to 2007 Low twenties was the norm. Calling the dilution of the fresher cap by pacific and atlantic waters to the point that halocline stability is seriously compromised an increase in freshwater content is pure misdirection.

45
Arctic sea ice / Re: The 2020 melting season
« on: July 16, 2020, 10:38:10 PM »
I split the Hycom month animation of thickness and this is three weeks ago, today, and forecast in a week.
The melt last three weeks has been phenomenal. Maybe of even more concerns is the rapad rotation of the pack, looks at risk of clearing out the entire atlantic front above greenland back to the lomonosov from lincoln to the pole. And unravelling the thickest ice from CAA to the pole into dispersed zombie floes in the Beaufort, Chukchi, and ESS.

46
Arctic sea ice / Re: The 2020 melting season
« on: July 15, 2020, 10:42:02 PM »
Hycoms concentration plummeting from ESS, through centre of Chukchi and Beaufort to mckenzie delta. Right now decent fetch winds hitting the laptev ice front with warm ssta and over 2.6m waves. Pity nullschool cuts off waves nth of 77deg, probably bigger at the ice edge. click to animate Hycom.
Edit: Euro has 3.5 m further out. Windy clipping further nth.

47
Arctic sea ice / Re: Arctic Ocean salinity, temperature and waves
« on: July 07, 2020, 11:05:27 PM »
Seems good support for Hycoms prediction of rapid export of thickest ice from CAB along Beaufort and Chukchi Alaskan coast to soon be cut off by rapid meltout starting from centre out to coast of these seas.
Do we have any active sensor buoys in centre of these seas Uniquorn? [Edit: oops, answer is yes, missed 114 on your chart]
Click to play animation:

48
Arctic sea ice / Re: Arctic Ocean salinity, temperature and waves
« on: July 07, 2020, 10:51:35 PM »
Drift charts for those buoys to show locations of these well above melting point temperatures under the ice.

49
Arctic sea ice / Re: The 2020 melting season
« on: July 07, 2020, 09:19:07 AM »
Compaction is a strong extent killer and makes for big headlines. The more important questions at this stage are what happens with area - which also dropping fast, and especially volume/thickness - which one can only imagine is breaking some daily records.
I note that wind-induced Fram export has not started yet. The smaller Nares is already half empty and racing for the exit.

Well this image from June 30 in the physics.org article:

https://phys.org/news/2020-07-latest-mosaic-floe.html

about the unusually thin ice Mosaic has encountered is the first I have seen them release giving an honest view of conditions. Not the usual puff pieces about haircuts and how well resetting up all the equipment is going, or cute polar bears.
This area was getting cooled winds from the mid basin and probably less sizzle than most anywhere else in CAB so not looking flash. Also rocks and shelfish thawing out of the central fortress floe show it is ex ESAS fast Ice, and they report most ice in region was only around 50cm, compared to 1.6m usually found in same area where they started in late 1990s.
Stones thawed out of fortress also attach.

50
Arctic sea ice / Re: SMOS
« on: July 06, 2020, 10:55:14 PM »
Only beige pixels now are tiny spot in foxe basin. Even red to purple scarce in arctic basin.

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