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Messages - wdmn

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1
Quote
I hope that some of the readers of this forum agree.

Indeed.

2
Arctic sea ice / Re: The 2020 melting season
« on: September 12, 2020, 03:58:33 PM »
It's not like its the first time...

Can I safely assume that you are aware that the AWI is located here:

https://en.wikipedia.org/wiki/Bremerhaven

and not here?

https://en.wikipedia.org/wiki/Bremen,_Indiana

3
Consequences / Re: Climate change, the ocean, agriculture, and FOOD
« on: September 11, 2020, 08:55:27 PM »
Alaska's Salmon Are Getting Smaller
https://www.theguardian.com/environment/2020/sep/08/shrinking-salmon-alaska-fish
.......

E. P. Palkovacs, et.al., Recent declines in salmon body size impact ecosystems and fisheries, Nature Communications, 2020
https://www.nature.com/articles/s41467-020-17726-z

As a commercial salmon fisher on the Yukon River (in Canada) since 1984, I, and all other fishers, have been acutely aware of this phenomenon since the 1980s.
Because we, both indigenous and non-indigenous fishers alike, typically had low levels of academic qualifications, our observations were resolutely discounted and disparaged by fisheries scientists for years and years.
We are still being ignored: It has always been obvious to us that the prime driver of the loss of the larger salmon has been size-selective fishing, undertaken of multiple salmon generations.
And yet, in this article, fishing is not identified as a driver because they had insufficient data.
They could have set a precedent and asked fishers.
Fishers selectively harvested the largest salmon for all the reasons that the largest salmon are identified as being important in the article.
This effect on salmon size is, in human life terms, permanent.
We have not only literally decimated the stocks, we have driven a permanent phenological change.
We could so easily have taken action, and fishers did, on multiple occasions, propose fishing methods to reverse the trend, before it was too late, but the proposals were not deemed sufficiently science based.
Unlike the scientific management that is driving the stocks to extinction.
We call it #ManagingToZero.

4
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: September 09, 2020, 06:46:33 AM »
https://data.meereisportal.de/maps/latest/extent_long_n_en.png

.... Have we reached the bottom?


Not yet it seems
01.09 3.60
02.09 3.56
03.09 3.50
04.09 3.39
05.09 3.39
06.09 3.39
07.09 3.41
08.09 3.32

5
Antarctica / Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE
« on: September 08, 2020, 03:57:52 AM »
In regard to the findings of the linked reference, Andrew Dessler states: "So energy imbalance is presently +0.87 W/m2/K. How much more does the Earth have to warm to wipe out that imbalance? That connection between energy imbalance and temperature is known as the climate sensitivity.

If climate sensitivity is ~0.75 K/(W/m2) (corresponding to ~3°C for doubled CO2), then that tells us that we need to warm the climate about 1°C *more* to reach energy balance, at which point the Earth will be in energy balance.

Except it won't be. We're still emitting carbon dioxide, so by the time the planet has warmed enough to wipe out the +0.87 W/m2 of energy imbalance that we measure today, we'll have emitted a whole lotta CO2 that will have increased the energy imbalance."

However, if the effective climate sensitivity is higher than that assumed by Dessler, then GMSTA will increase faster than assumed by Dessler:

von Schuckmann, K., Cheng, L., Palmer, M. D., Hansen, J., Tassone, C., Aich, V., Adusumilli, S., Beltrami, H., Boyer, T., Cuesta-Valero, F. J., Desbruyères, D., Domingues, C., García-García, A., Gentine, P., Gilson, J., Gorfer, M., Haimberger, L., Ishii, M., Johnson, G. C., Killick, R., King, B. A., Kirchengast, G., Kolodziejczyk, N., Lyman, J., Marzeion, B., Mayer, M., Monier, M., Monselesan, D. P., Purkey, S., Roemmich, D., Schweiger, A., Seneviratne, S. I., Shepherd, A., Slater, D. A., Steiner, A. K., Straneo, F., Timmermans, M.-L., and Wijffels, S. E.: Heat stored in the Earth system: where does the energy go?, Earth Syst. Sci. Data, 12, 2013–2041, https://doi.org/10.5194/essd-12-2013-2020, 2020.

https://essd.copernicus.org/articles/12/2013/2020/

Abstract
Human-induced atmospheric composition changes cause a radiative imbalance at the top of the atmosphere which is driving global warming. This Earth energy imbalance (EEI) is the most critical number defining the prospects for continued global warming and climate change. Understanding the heat gain of the Earth system – and particularly how much and where the heat is distributed – is fundamental to understanding how this affects warming ocean, atmosphere and land; rising surface temperature; sea level; and loss of grounded and floating ice, which are fundamental concerns for society. This study is a Global Climate Observing System (GCOS) concerted international effort to update the Earth heat inventory and presents an updated assessment of ocean warming estimates as well as new and updated estimates of heat gain in the atmosphere, cryosphere and land over the period 1960–2018. The study obtains a consistent long-term Earth system heat gain over the period 1971–2018, with a total heat gain of 358±37 ZJ, which is equivalent to a global heating rate of 0.47±0.1 W m−2. Over the period 1971–2018 (2010–2018), the majority of heat gain is reported for the global ocean with 89 % (90 %), with 52 % for both periods in the upper 700 m depth, 28 % (30 %) for the 700–2000 m depth layer and 9 % (8 %) below 2000 m depth. Heat gain over land amounts to 6 % (5 %) over these periods, 4 % (3 %) is available for the melting of grounded and floating ice, and 1 % (2 %) is available for atmospheric warming. Our results also show that EEI is not only continuing, but also increasing: the EEI amounts to 0.87±0.12 W m−2 during 2010–2018. Stabilization of climate, the goal of the universally agreed United Nations Framework Convention on Climate Change (UNFCCC) in 1992 and the Paris Agreement in 2015, requires that EEI be reduced to approximately zero to achieve Earth's system quasi-equilibrium. The amount of CO2 in the atmosphere would need to be reduced from 410 to 353 ppm to increase heat radiation to space by 0.87 W m−2, bringing Earth back towards energy balance. This simple number, EEI, is the most fundamental metric that the scientific community and public must be aware of as the measure of how well the world is doing in the task of bringing climate change under control, and we call for an implementation of the EEI into the global stocktake based on best available science. Continued quantification and reduced uncertainties in the Earth heat inventory can be best achieved through the maintenance of the current global climate observing system, its extension into areas of gaps in the sampling, and the establishment of an international framework for concerted multidisciplinary research of the Earth heat inventory as presented in this study. This Earth heat inventory is published at the German Climate Computing Centre (DKRZ, https://www.dkrz.de/, last access: 7 August 2020) under the DOI https://doi.org/10.26050/WDCC/GCOS_EHI_EXP_v2 (von Schuckmann et al., 2020).



6
Arctic sea ice / Re: The 2020 melting season
« on: September 06, 2020, 08:22:15 PM »
Snow will indeed increase (marginally) but eventually this will transition to rainfall

7
Consequences / Re: Arctic Amplification and Extreme Weather
« on: September 05, 2020, 05:21:47 PM »
And 2020. Yikes. Very bad!

I know I sound a bit combative here but I am not trying to be rude. The blended years since 2012 do not show the WACC-y signal since it is not yet consistent EVERY year but it has been since 2017 I believe.

The picture shows a cold America. Continents is multiple and Eurasia is not that cold. Hence is does not show the signal.
https://journals.ametsoc.org/jcli/article/33/18/8069/348406/Severe-Cold-Winter-in-North-America-Linked-to
Severe Cold Winter in North America Linked to Bering Sea Ice Loss
Quote
Our study under the present climate shows that severe cold winters in North America are linked to Bering SIA loss via the negative ALO–ANA pattern. In the near future, with little or no sea ice in the Bering Sea, this negative ALO–ANA pattern may occur more frequently, or a completely different climate mode may appear. To predict severe cold winters in North America under global warming, it will be necessary to model regional and general climate systems with little or no sea ice.

8
Arctic sea ice / Re: The 2020 melting season
« on: August 08, 2020, 01:26:35 PM »
Again the actual poof event in a slightly higher resolution (I must admit that on the multicolored Bremen graph it looks even more devastating):
I understand why extent isn’t collapsing but I’m scratching my head trying to figure out why area isn’t dropping like a stone.  Makes no sense looking at Bremen and worldview.

9
Arctic sea ice / Re: The science of ice ridging and rafting
« on: August 03, 2020, 03:09:20 AM »
Going over some older material, I found this on the Mosaic thread which I thought was of interest to this thread.

Here is an English Translation of a transcript of the latest Podcast from the MOSAIC Website that is only available in German.

The Podcast was posted last Wednesday (January 22)  at 5:57 PM on the MOSAIC Website (in German) - the recording itself was probably made 8. January

Installment 11 – thick ice, four-legged visitors and slight frostbite

In the meantime, the team around the new leader of the MOSAIC-Expedition, Christian Haas, has accustomed itself to life on the ship and to the camp on the Ice Floe. In this installment the Sea Ice physicist goes into detail about the composition of the ice and how it is continuously changing. Apart from this, Dr. Haas also reports on measurements made by other scientific disciplines and explains how an aircraft landing-strip is made on the ice. The continual decrease in temperatures and the ongoing polar night present further challenges for the members of the expedition. And, this week, the camp got another animal visit.

…..[Ed.: Just so that transcript readers don’t miss out on the atmosphere of the podcast they should know that it is preceded and ended by sound recordings of strong wind and creaking ice….]

Arctic Drift – The audio logbook.

Christian Haas:   At the moment we are at 87 degrees 8 minutes North. During the MOSAIC expedition the ship this the most Northerly that the ship has been. [Ed.: According to the positions reported on MOSAIC webpage this would date the time that this recording was made a being around 8. January]

Commentator: In the meantime, the leg 2  Team has adapted to arctic conditions. The crew around the new  Expedition leader Christian Haas has familiarised itself  with the Icebreaker  Polarstern and the condition on the home floe. Dr. Haas himself is head of the Sea Ice Physics section of the  Alfred Wegener Institute and can precisely explain what an ice floe is and why the ice in the arctic is constantly changing.

Christian Haas: we are always using the term “ice floe”, but everyone probably imagines something different under this term…and at this time of year, in the middle of winter, there aren’t really any, anymore. When the  Polarstern arrived here at the beginning of October, it really was the case that there were individual ice floes drifting in the water. They were separated from each other by water or thin ice. But the ice and the ice floe formed a unit and could be regarded as a swimming platform.   The MOSAIC ice floe had a diameter on the order of two to three kilometres. But since we have been here and the winter has begun, the whole area around us has frozen solid, so that one can’t make out individual ice floes, because the borders between them are not visible, except with the help of Satellite data. Nonetheless it’s the case that the ice floe isn’t a plate, it isn’t a simple uniform plate of ice, but, as before, it regularly fractures and is displaced by shear zones. Till now we have just had a lot of luck that such shear zones and fractures didn’t go directly through our camp but were some distance away. Just yesterday we made an exploratory tour with snowmobiles to the West and East and at a distance of about two to three kilometres in each direction we found tears and shear zones.  With that we could say that the floe is  two to three kilometres in size, but the Northern and Southern boundaries haven’t been found yet. 

Commentator: The ice and the alterations in it are being constantly observed. Using different kinds of measurements it is possible to completely understand the displacement of the ice. Many researchers view these displacements as a danger, because they can lead to interruption in their research. Others welcome the possibility being able to  observe and analyse them directly. 

Christian Haas: The ship’s radar, that every 10 minutes makes an image of the surroundings within a radius of 5 kilometres, helps us a lot. When one looks at a time series of these images it’s like looking at a film of the ice movement. Most of the time the ice is stable, but sometimes one sees shear events, where, because of a difference in the extent of ice-drift in different regions, a part of the floe suddenly slides by between several metres up to as much as 100 metres relative to the other part. These zones produce tears and the formation new pack ice ridges.

Christian Haas: For most of our colleagues here the tears and the formation of pack ice ridges are seen as a hazard, because they interrupt research. But for us as researchers and  for the whole MOSAIC project of course it’s an important process that we want to investigate.  This is because we want to better understand why the ice in the arctic has declined so much during the last few decades and to find out what processes result in the ice becoming thicker or thinner. The growth of pack ice ridges, the deformation of the ice and the sliding of pieces of ice on top of each other  is a very important process and can make ice much thicker than it would become through solely as the result of freezing through contact with the cold atmosphere. For this reason the sea ice researchers and remote sensing experts who are involved in our project are very thrilled to be able to observe such deformation events at first hand and to be able to see how the ice can continuously become thicker through floes fracturing and sliding on top of each other. 

Commentator: In the meantime, the floe ice is circa one metre thick and has doubled in thickness since the beginning of the expedition in October.  In comparison, the so called “pack ice ridges” are considerably thicker. To investigate them more thoroughly various instruments have been installed in the ice.

Christian Haas: We see here that some pack ice ridges are up to three metres high. Pack ice ridges are like icebergs, that means that roughly a tenth of appears above the surface and nine-tenth of them are under water. It follows that where there are pack ice ridges the ice can be 10, 20 or even more metres thick. We have observed this with our remotely controlled ROV, with which we were able to make  sonar measurements of the ice depth and we have already found ice thickness of over 10 metres. In our last big action, we installed a number of instruments in some of these pack ice ridges. We call this the “Pack Ice Ridge Observatory” and we want to use it to observe on the one hand how the underside is eroded by currents and by the warmth that is present in the sea water and on the other hand  how the pack ice ridges are frozen from above. In addition, we want to know how, because of their rough surfaces, they are affected by turbulence in both air and water and whether this is important for their growth or melting.

Most ice measurements are made by drilling holes in the ice and then placing instruments underneath the ice or in it. That’s exactly what we have to do here. We have placed large measuring devices, that require large holes to be drilled, at the periphery of the pack ice ridges and underneath the ice. These are for instance instruments that measure water currents and turbulence.  Then we embedded thermistor chains over the whole ridge as well as in the thickest ice, that was more than 8 metres thick in places. With these chains we can observe how the ridges cool, how they freeze in the centre, and how the processes of erosion and disintegration  take place on their undersurface.

Commentator: Research in other scientific disciplines is also ongoing. A great deal of weather data is being collected both on the Polarstern and  in the Ice Camp. Still lower temperatures than the current low temperature of minus 35 degrees have been measured there.

.....

Commentator: Christian Haas is looking forward to the coming weeks and the upcoming research work, although the conditions for it won’t be made easier by the continuing polar night and the further decrease in temperatures. He is very focused on keeping the goal of the MOSAIC expedition in his sights.

Christian Haas:  We are still moving into February and March, that’s actually the coldest season in the arctic. That means that weather conditions will become even more extreme. Nonetheless, I believe we will continue to work enthusiastically on the ice. Because now, just as we are slowly beginning to get good time-series measurements of atmospheric conditions and of ice and water conditions, the information is becoming increasingly interesting and we are getting nearer to fulfilling the goal of the MOSAIC expedition to investigate the interaction between the atmosphere, ocean and  ice and, and we shouldn’t forget that, the Biology of the arctic. So I hope that we will continue to be able to work unhindered. Naturally one or two ice deformation events should also take place, if possible, at quite a distance from the  ship. We will continue to expand the radius of the area that we move in. Apart from that, I hope that we might indeed get a storm that will bring us some snow. Till now the snow has been very sparse, the snow cover is between eight and twenty centimetres. And what we also hope for, even if it may sound paradoxical, is that at some stage we get an intrusion of warm air that will temporarily give rise to very high temperatures and even to a little rain, as has been seen with increasing frequency in past years and about which there has been much speculation as to the effect it has on ice cover and ice growth. We now have a unique opportunity to observe the phenomena on the spot and that is absolutely necessary to better understand these processes.

10
Arctic sea ice / Re: The 2020 melting season
« on: August 01, 2020, 07:47:19 PM »
So what happens next?
weatherdude will post something that proves this year is no big deal  ;)

11
Arctic sea ice / Re: The 2020 melting season
« on: August 01, 2020, 07:40:13 PM »
Someone complains they are not actually attached?

12
Arctic sea ice / Re: The 2020 melting season
« on: August 01, 2020, 10:05:47 AM »
In physical reality, what matters most is thickness distribution (and volume), then area, then extent. If the ice is driven in a compacting transport, extent will plummet with not much physical impact, while the reverse is also true under a divergence regime. What we can see unfortunately with the satellites and models is the opposite, extent in high accuracy, area in medium accuracy, thickness distribution and volume with low accuracy and delays.
This allows both parties to have numbers and data on their side, which is fine, just has to be interpreted according to physics and not just visible numbers on a chart.
The sunny July did huge damage to the CAB in terms of volume, and the open Siberian seas are a disaster waiting for imports, while the Atlantic front has huge amounts of open water as in 2012 and 2016, very unlike 2019. OTOH the Beaufort is full of ice and the CAA and Greenland Sea are still holding up. The question we do not know is how much of the remaining ice is in marginal conditions - still whole for now but will melt out by mid-Sept. This is what will dictate the area numbers, and partially the volume numbers as well, as volume calculation is tied to measured area changes. The extent numbers will be dictated by area numbers, but very highly affected by compaction or divergence - very visible, much less important IMHO. 2016 was almost as low as 2012 in terms of area, but very high up in terms of extent.
My take on things is that the ice is thinner than appears, due to the impact of July insolation and due to very high movements in the last few weeks, which induced faster bottom melt. I have never seen so many days where the CAB was entirely visible, and this while the ice was doing a crazy dance around the basin. Then came the cyclone with movements induced in the other direction. The CAA has been sweltering in heat and the ice is all broken up. So I expect a some point a lot of the ice which originated with a standard FYI thickness will melt out, and so will some of the thinner MYI. This will probably leave us with a total area record or near-record, even though the Beaufort may not be in record territory at all. Oh yeah, I also expect a volume record. I can't say the same for extent, which might be far away from 2012's record, though surely below 2019. This depends on random September factors so can beat the seasoned forecasters easily.
August is upon us, the answers will be clear in a few weeks time, not much longer to wait.

13
Arctic sea ice / Re: The 2020 melting season
« on: July 31, 2020, 10:36:41 AM »
I'm really surprised at how long it can take for what appears as slush on worldview to melt out.

...

Is it the lack of movement, which creates a cool pocket?

SST shows a -ve anomaly. Therefore my bet is on the cool pocket (i.e. micro-climate).

14
Arctic sea ice / Re: The 2020 melting season
« on: July 31, 2020, 07:23:25 AM »
I'm really surprised at how long it can take for what appears as slush on worldview to melt out. For example this patch of "ice" in Hudson's Bay, which -- according to nullschool -- is in water well above -1.8C. Why wouldn't this go poof? Is it the lack of movement, which creates a cool pocket? Surely if there was wind this would disappear over the course of a day?

This is definitely not MYI - the Hudson melted out completely last year (if you want to verify this, look at EOSDIS Worldview starting c.a. 10th September last year. The following days have clear skies over different parts of the Hudson proper, no ice in sight.

ArcticMelt2 pointed out that these could be pressure ridges. I'd like to extend that to this being remnants of pressure ridges and stacks that have been pushing and piling up against the shore all winter. These thick chunks have now drifted away from the coast and are slowly but surely melting away.

But this shows how unduly optimistic/pessimistic (take your pick)  the "this ice looks like slush, should melt out in a couple of days" statements that one sees frequently in the forum are.

I’m sorry, but I followed this discussion back as far as I could and no one said anything about MYI. The people involved in this discussion raised reasonable questions, and had reasonable responses.

15
Arctic sea ice / Re: The 2020 melting season
« on: July 31, 2020, 06:13:43 AM »

In general though, the current weather outlook should favour the sea ice but whether it will or not this year remains to be seen.

You said the same thing last night, and I asked you about it and you did not respond.

I’m not trying to be rude. I just want to understand what you see that I am missing.

What is it in the current weather pattern that you think favors the sea ice?

He recently made the statement that the huge losses/highly anomolous temps were only over areas with low thickness according to piomas. 

I responded asking how that is so when the Southern CAB and Atlantic side have been torched which are the only two areas where piomas had abnormally thick ice. 

I essentially said that's a pretty disingenuous statement from an intelligent poster.

Didn't get a response.

That kind of wrangling the discussion thread is not the most honorable way for a man to participate here trying to be of total integrity regardless of if they end up wrong

I might end up wrong.  Has happened a lot.


Anyways regardless of whether he responds he is right. The current weather is generally good for the ice.  Or is trending that way slowly as the anomolous heat backs off over the Eastern half of the CAB.

The cooler overcast over the Pacific side is good for slowing melt

Although it won't prevent most of that ice from melting since it's so thin now which can be inferred  through modis and amsr2 products.






The general wind pattern is currently a reverse dipole which is spreading the ice out.

The ice isn't going to move very much so only the edges get displaced into the inferno waters

While outgoing winds dampen waves within the ice pack and blow's the torching water away from the ice.

In this case the Chuckchi, ESS, Laptev are all in the exit zone of the reverse dipole.

But it' varys from day to day.



The bigger question is what is being protected?  The Pacific ice South of 80N is toast.

Some ice in the Beaufort but mostly the Western CAB will survive.

But almost all of the ice that Bremen has categorized as 35-60 percent Concentration (the greenish hues) is toast.

Thats been like the entire Pacific side South of 80 the last 3 days.  The rest of the CAB has been smoked. The Southern CAB we will find out soon how bad.

So yeah what's left in parts of the CAB will benefit from melt being slowed.

Whoi bouys show sustained bottom melt in the Beaufort at least to 75N.  They also show a quick spike in salinity the last couple days.  A sign of near surface overturning of the fresh water layer.

If that is the case the layer below it is torching.










16
Arctic sea ice / Re: The 2020 melting season
« on: July 30, 2020, 06:37:47 AM »
Is it just me or do others get the shudders when they see that Will elf? Sorry, OT.

17
Arctic sea ice / Re: The 2020 melting season
« on: July 29, 2020, 08:47:16 PM »
My prediction of a remarkable slow down in ice extent reduction didn't seem very popular here.
<snip>
I suspect it was less that you said it would slow down, and perhaps more your implication (perhaps not clearly indicated) as to  *why* it was going to slow down.

The slow down we see currently is not the result of a "good thing";  that's obvious when you look at the area numbers and see continuing century-break losses.

The storm and dipole are blowing up the ice, scattering the Beaufort and shoving CAB ice back across the Laptev.  A less ideal direction for ice movement would be hard to find. 

When the dust settles there will be more pieces, and smaller, and a lot of them will likely disappear in a hurry.

18
Arctic sea ice / Re: The 2020 melting season
« on: July 29, 2020, 08:30:59 PM »
This thread becomes completely unreadable since quoting is done incorrectly all over the place.

The things YOU say must be AFTER the closing quote tag (i.e. [ /quote ]).

For EVERY opening quote tag (i.e.[ quote ]) there must be a corresponding closing quote tag (i.e.[ /quote ]).

Everything you are not responding to should be deleted.


It's not too hard folks.

19
Arctic sea ice / Re: The 2020 melting season
« on: July 28, 2020, 11:01:01 PM »
This was posted by MOSAIC today. Uniquorn has more information available on the MOSAIC thread and the buoy thread.

DMI uses a model that is heavily weighted towards the pole and tends to keep the temperature pegged close to 0C over the ice.  The heat flowing over the North Pole right now is incredible!

The weather forecasts are showing lots of WAA from areas that have seen record high temperatures, including Svalbard which is having a historic heat wave.

20
Arctic sea ice / Re: The 2020 melting season
« on: July 28, 2020, 10:11:09 AM »
There is often a discrepancy between conservative scientific predictions for the melting season and the amateur predictions on this forum. This years, it "feels" "we" are right. NeilHamp, rest assured said posts were not criticizing you, but were expressing incredulousness at the conservative scientific prediction of the Arcus report. Thanks for bringing it to our attention.
Time will tell if said sentiment was correct or not.

21
Arctic sea ice / Re: The 2020 melting season
« on: July 28, 2020, 08:50:26 AM »
'nite , Jim . That 58mb differential across the basin should get things moving ..

After much tossing and turning I woke early this morning to the sight of a "picture perfect" reverse dipole. 969 hPa plays 1029, according to the CMC at least:

https://twitter.com/jim_hunt/status/1288002593789181952

22
Arctic sea ice / Re: The 2020 melting season
« on: July 27, 2020, 08:52:47 PM »
Sea Ice Prediction Network for September outlook.

https://www.arcus.org/sipn/sea-ice-outlook/2020/july

23
Arctic sea ice / Re: The 2020 melting season
« on: July 26, 2020, 10:43:21 PM »
Peeks through the clouds show the effects of the stiff breeze over the Peary channel.
Click to run.

24
Arctic sea ice / Re: The 2020 melting season
« on: July 26, 2020, 04:50:34 AM »
      After looking at the GFS July 25 18Z forecast, two things jump out that no one has commented on that may be significant. 
 
1.  It looks like the low pressure on the Pacific side and the moderate but not trivial high pressure on the Atlantic side is creating a sustained reversed-Arctic transport wind field moving already fractured ice toward the Laptev Sea where the high surface temperature is an ice killing zone.  The wind speeds are not that high, mostly below 15 knots, but they are persistent.  I don't know how much ice and how far the ice will actually move, but it could e one more negative influence to bleed out CAB ice.   If signficant, the Laptev bite may not have to reach the North Pole ice, that ice may come out to meet the Laptev bite halfway.




2.  Some of the surface heat in the CAA - Greenland - North Pole triangle is from a 2.5 day period of clear sky extending right up to the pole.  Looking at the surface insolation chart, even late July is still close enough to solstice for that to be another significant dagger into the heart of the CAB.  Thus, energy that does not even show up as changing the temperature will be going into melting ice. The triangle used to be home to some of the thickest toughest multiyear ice.  The ice that remains there this September could be a remnant Extent with none of those other qualitative characteristics.   


Pale, light blue = clear sky over ice.  Dark blue = clear sky over water. 
Green - rain, "Aqua-blue" = snow.

    With only 6-8 years as an Arctic voyeur, I don't know enough to be apocalyptic, but FWIW in addition to what we are hearing from the old hands on deck, add one more "Holy Cow, I've never seen anything like 2020".  After all the melt season conditioning this year, if these forecasts verify the cumulative effect of the different Arctic regional weather events looks to be in the same league as the GAC2012. 

    No, the low pressure system is not as intense or as long lasting as GAC2012, but this Arctic-wide scenario has someting going on just about everywhere: cyclone in the already fractured Beaufort, unprecedented subsurface heat in the Beaufort, roasting top down heat in the CAA, clear sky and heat in the heart of the CAB triangle, extensive and intensive heat across the entire Atlantic front.  All this happening to ice that has been softened up by May melt pond set up, and extended periods of heat and clear sky in June and July.  So the widespread melt pressure is going onto ice with far below normal resistance.

     Thus the cumulative effect looks equally as significant as the GAC2012.  If I'm wrong, let me know.  That's how I learn.

These are great insights.

That sunny triangle is quite important.
We are at the very end of the INSOLATION period for 80-90N so soaking up another few days of insolation will take off a few more CM of ice. 

The other noticible thing on those forecast graphics is the warmed surface to near surface temps from land and downsloping.  This year is rivaling 2011 in that area if not beating it.

That is so bad for the old Southern CAB ice. 

Paul is right about the vortex being compact and that it likely keeping a small deep cloud cyclonic regime limiting the cooling.... Instead of the large broad weak vortex regimes we often see in summer that develops a large cold pool with -5 to -8C 850mb temps.

This could become an issue if say after the vortex a dipole anomaly develops.  With a tiny weak cold pool the warm air advection from the dipole could become established immediately.

WDMN--

So glad you posted that.  I almost made that animation myself.

Pretty amazing how fast that solid ice straight craps out.

25
Arctic sea ice / Re: The 2020 melting season
« on: July 25, 2020, 08:19:28 PM »
Now the ECMWF has a convincing forecast that agrees well with the GFS of a deep low that is in pretty much the worst possible location for the ice. The ice will be mixed into the ridiculously warm waters on the Siberian side. Now it's looking like this is going to be an historic year for sea ice.

Insane warm air advection from the CAA and hot compressing air downsloping off of Greenland towards the pole and across to Siberia. With strong winds to mix the heat down to the ice.

click to play (courtesy of Tropical Tidbits)

26
Arctic sea ice / Re: The science of ice ridging and rafting
« on: July 23, 2020, 11:54:45 PM »
Very good thread. Add the assumption of deep summer, ice core temp is at the melting point of -1.8C, and air temps are above that, so the ice is structurally weaker than in winter and there can be no freezing together of floes or rubble. And that we are interested in events in the middle of the ocean. It is quite obvious that some ridging can occur even in summer with enough pressure against a static shore.

People on the melting season thread have mentioned seeing ridging on the Pole Cam, may it rest in peace. Does anybody have access to those images? Or can anyone post accurate recollections of such events?

27
Arctic sea ice / Re: The science of ice ridging and rafting
« on: July 23, 2020, 11:25:57 PM »
the formation of the sea ice ridges, they require freezing (-1.8 ) air temperatures to form.
https://www.eolss.net/Sample-Chapters/C05/E6-178-66.pdf

The initial phase starts during ridge formation and is characterized by the formation of
freeze-bonds. Three different heat fluxes are important: a) the surface flux ( qsur ), into the cold surrounding air, b) the oceanic flux ( qocean ), from the ocean beneath and c) the
internal fluxes ( qre ), in between the cold pieces of ice and the warm water pockets
inside the keel (Figure 3). The surface flux freezes the water pockets from the top and downwards and creates a cold front that defines the consolidated layer. The initial cold content of the ice is partly spent in making freeze bonds and partly consumed by the oceanic flux. The fraction that goes into making freeze bonds depends on the initial ice temperatures, the block thicknesses, the ridge size and the oceanic conditions. When all the ice and water below the cold front is isothermal that is at the freezing point of the surrounding water the initial phase ends.
The rubble beneath the consolidated layer is thermally insulated by the freezing front on top of it, and feels only the water below. Since the conditions are isothermal there is no longer any cold reserve available and the rubble decays continuously. The rubble transforms from individual ice blocks with freeze bonds to an ice skeleton with a hierarchy of pores, from a few centimeters and up to meter(s).
In the decay phase the ridge is heated both from the top and from the bottom. The ridge now either melts completely, or it transforms into a second-year ridge during the summer. Several processes take place. On the surface the warm air and the sun radiation melts the snow and the surface ice and creates relatively fresh melt-water. Its freezing point is above the temperature in the rubble so it will freeze as it drizzles down in the keel. This freezing process release heat and increases the temperatures in the rubble. In this way the decay phase includes both melting and freezing. Freezing can take place as long as there is cold capacity (ice temperature less than the freezing point of the melt water) in the keel. However, another mechanism can contribute to further consolidation. If the pore water salinity is changed cyclically, either by periodic surface melting or by tidally driven river runoff the ridge could actually expel heat into the surrounding water
and contribute to further freezing (consolidation). This mechanism is only shown in laboratory investigations and in simulations. Finally the ridge keel could collapse and in this way decrease the porosity and increase the degree of consolidation. By the end of the melt season the ridge has become a second-year ridge.

28
Arctic sea ice / Re: The 2020 melting season
« on: July 23, 2020, 02:03:49 PM »
Lots of posts about possible cyclones associated with low pressure developing here & here.

But not a squeak about possible wind speeds? The force applied by the wind is proportional to the square of the wind speed. So a 50 km.p.h wind will apply 4 times the force of a 25 km.p.h. wind to a surface. Wind speed makes all the difference in the world ?

I guess also the state of the ice is important - wind howling across an unbroken flat ice sheet would be far less damaging than a somewhat lesser wind on a broken up ridged surface with multiple open water leads?
____________________________________________________________
For people who like a bit of mathematics........

Calculating Force Based on Wind Speed
Calculating the force of wind requires the mass of air and acceleration of wind. The average density of a mass of air at sea level equals approximately 1.229 kilograms per cubic meter. The area the wind hits is measured, in this case, in square meters. The mass of air hitting a surface then equals air density times area. The acceleration (a) equals the square of the wind speed in meters per second (m/s).
Use the formula force (F) equals mass (m) times acceleration (a) to calculate the force in Newtons (N). One Newton equals one kilogram-meter per second squared (kg-m/s2).
Be sure to use the matching units. In this calculation, the average air density at sea level equals 1.229 kilograms per cubic meter (kg/m3). The area of air impact equals 1 square meter. To calculate the force of a 5-mile-per-hour wind, first convert the wind speed to meters per second. Using an online converter shows that 5 mph equals 2.24 m/s.
Filling in the formula force equals air mass (Am) times wind speed squared (F = Amxa2) gives this calculation:
F = (1 m2) × [1.229(kg/m3)] × [2.24(m/s)]2.

Completing the math shows that F = 6.17 kg-m/s2 or 6.17 N. So, a breeze of 5 miles per hour would have just enough force to lift a standard kite.

29
Arctic sea ice / Re: The 2020 melting season
« on: July 23, 2020, 09:06:40 AM »
I've softened some of Friv's comments above but left the Friv-binntho exchange intact as it saves me some speeches. While I fully agree with Friv's analysis of the melt momentum, and share his frustration with some of the comments on this thread, binntho is exactly right in his rebuttal - wrong people are wrong, not trolls, and by posting wrong opinions they are not derailing the thread. They are probably derailing their future reputation as ice forecasters, and showing that even on the famed ASIF people can be spectacularly wrong.

Please avoid continuing this meta-discussion on this thread, consider binntho's as the last word. I will continue editing if needed when posters make personal comments about other posters' character or intentions. Of course, feel free to comment about other posters' wrongness.

One thing I will not allow further without some references - the claim that ice in the middle of the ocean is ridged and stacked in the summer under a HP ("compaction") regime. While I know nothing much of the subject, this has been a recurring talking point (esp. Michael Hauber) with no proof presented, and under dispute by many other posters. So I ask further claims of this type to be made in a separate thread and scientific references be presented to bolster said claim.

30
Arctic sea ice / Re: The 2020 melting season
« on: July 22, 2020, 09:15:27 AM »
In this sector open water area today roughly about 55,000 km² (yesterday 50,000 km²).

31
Arctic sea ice / Re: The 2020 melting season
« on: July 22, 2020, 03:49:25 AM »
OK, this is it.  This is our compact, unrubbled extent.  Our CAB Bastion if you will.

It's due north of Ellesmere.  The lower left hand corner is grounded on an island in the CAA.

To the left, it is bounded by the Beaufort, which *is* rubble, and the upper left hand corner is where the ESS and Chukchi melt in-situ are chewing into it.

Directly above, the Laptev ice boundary is chewing northward at as much as 50km/day, and will almost certainly be passing 85N before the end of this.

To the right, you have a combination of ice being rubbled, melting in situ as it is dumped into the Fram conveyor, or shoved into the emerging killing zone along the Atlantic front to the north of Svalbard and FJL.

This image is about 1.5 million km2.  There is far too little that will survive outside of it for my comfort.

32
Arctic sea ice / Re: The 2020 melting season
« on: July 21, 2020, 12:04:50 AM »
I think the discrepancy between extent and area is explained by two factors.

One is the melt pond drainage mentioned by Lodger and FOW above.

The other is lack of dispersal.

We are getting sooo sidetracked on a very basic issue.  The microwaves that are used to measure the ice are very good at distinguishing between solid ice and liquid water in the winter.

They are not very good in the summer when fog and wet clouds and wet ice and dry ice and melt ponds and ect ... are involved.

Area is not easy to interpret in the summer because of the effects on how the microwaves “see” wetness.  Because of that, we use extent for the official data.

That is not great either, because it could have a margin of error as much as 85% in each measured grid. If I remember correctly, NSIDC uses grids of 25km x 25km so that number could be quite significant.

But, we don’t need to get bogged down in the problems with the microwaves and how they measure if we keep an eye on the visible spectrum on worldview.

At the end of the day, this year might or might not break some records regarding extent, area, or PIOMAS volume.  But we can see how bad it is by using our own eyes and thinking about the two most important factors 1) albedo and 2) latent heat of fusion.

33
Changes from June 30.

Laptev ... -89%
Hudson ... -85%
Barents ... -77%
Kara ... -73%
Baffin ... -71%
ESS ... -68%
Chukchi ... -46%
Greenland ... -26%
CAA ... -21%
CAB ... -19%
Beaufort ... -19%

34
Arctic sea ice / Re: The 2020 melting season
« on: July 19, 2020, 02:01:19 PM »
So I speculate that the ice thickness may be being maintained due to ice floes stacking on top of each other as they are compacted, and you demand some that I prove it with evidence, even though it was only speculation.

The primary means that sea ice thickness grows beyond the 2-3 m limit imposed by its thermal insulating characteristics (depends on air temp) is through Wintertime leads and ridges:

Quote
Hopkins, Mark A., Jukka Tuhkuri, and Mikko Lensu. "Rafting and ridging of thin ice sheets." Journal of Geophysical Research: Oceans 104.C6 (1999): 13605-13613.

https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/1999JC900031

That is how the oldest ice in the Central Arctic Basin was able to grow to 10 or even 20 m in thickness. However, this effect due to leads + ridging does not occur during the Summer melt season, so is not a factor at this time.

Summer rotten sea ice is too weak to survive mechanical compression due to winds which, during the Winter, would lead to slabs overiding each other to form ridges, and eventually thickening of the entire ice floe via bottom melt/refreeze (which flattens the ridge and spreads out the ice, and thus even out the thickness of the entire floe).

Cheers!

35
Arctic sea ice / Re: The 2020 melting season
« on: July 17, 2020, 08:07:17 AM »
I have seen such pieces sticking out and being stood up on the O-Buoy movies (which I've recently linked to again on the buoys thread), after what seemed like floe collisions. However, this does not make the ice stronger, these are small pieces and are prone to falling again, and in addition the part standing outside the water can catch the low sun easily, so I doubt this can make much difference and delay melt-out. I would expect a good defensive process requires very cold and structurally strong ice to succeed, so mid-July compaction would not do much good. On the contrary, I would expect floe edges to break and large floes to split apart during such pressures, so it is quite probable that this process actually speeds melt-out somewhat.
(Caveat - I am just an amateur here, cannot base this on actual science).

I think the situation is far more complex than that. The extension above the surface of the surrounding flows would be matched by a proportional "keel" below the underside of the general level of the ice. There would be a macro effect of increasing the friction resistance to any wind and a below surface in the water. As wind and current are not normally in alignment this would exert additional forces across the ice at local and regional levels. The resulting rotational forces would tend to increase the rate of the mechanic erosion of the ice structures.

36
Arctic sea ice / Re: The 2020 melting season
« on: July 17, 2020, 07:38:30 AM »
I have seen such pieces sticking out and being stood up on the O-Buoy movies (which I've recently linked to again on the buoys thread), after what seemed like floe collisions. However, this does not make the ice stronger, these are small pieces and are prone to falling again, and in addition the part standing outside the water can catch the low sun easily, so I doubt this can make much difference and delay melt-out. I would expect a good defensive process requires very cold and structurally strong ice to succeed, so mid-July compaction would not do much good. On the contrary, I would expect floe edges to break and large floes to split apart during such pressures, so it is quite probable that this process actually speeds melt-out somewhat.
(Caveat - I am just an amateur here, cannot base this on actual science).

37
Arctic sea ice / Re: The 2020 melting season
« on: July 17, 2020, 07:25:28 AM »

While my gut feeling is that floes are too weak to withstand stacking at this time, I recommend reading this recent excerpt from the Mosaic mission, testimony of the tremendous forces resulting from the crazy movement and compaction going on in the CAB in the last few days.

Click to zoom.


My thinking is that if there is thousands of kilometers of ice being forced into each other from different directions then something is going to give.  Perhaps floes don't get stack on top of each other.  Especially floes large enough to be visible in MODIS scale, i.e. 100s of meters across, that does seem quite unlikely.  But perhaps pieces can  break of the edge and tilt.  The ice might be generally 1 meter thick and some pieces 2 meters wide could break of the edge, tilt 90 degree and then you have a small piece of ice that is 2 meters thick, and the forces that are trying to push all the ice together have been relieved just that little bit.  And the idea of an ice shove - its not ice floes stacking on each other but ice ground up into lots of jagged chunks that pile up thicker than the sheet they came from.  I would be surprised if something like this doesn't happen at least occasionally on a small scale.  Whether it happens on a big enough scale to make a difference?  That is speculation and I'd love to have some definite data one way or the other.  That picture from the ship looks pretty flat, as does every other picture I can recall seeing.  If there was stacking/crumpling/tilting/shoving going on there would be jagged edges.  Maybe the boats avoid these areas.

38
Arctic sea ice / Re: The 2020 melting season
« on: July 17, 2020, 05:45:19 AM »
It can not be argued that we have (not) seen some extreme surface melting over the last few days.

I added the word "not" that I think you meant to put in there.

I don't think it's very scientific to try and draw boundaries around what can and can not be argued. Clearly there is visible and undeniable evidence supporting the massive extent declines being reported by JAXA. The 2D shrinkage is undeniable.

But there is room for reasonable people to question how much of that shrinkage is due to melting and how much is due to relocation.

There is a lot of evidence which will be forthcoming in the next two months which will shed more light on what has transpired during the GAAC. There isn't any reason to label less common perspectives such as those implied by Nico Sun (and his depiction of a negative current melting energy anomaly) as being invalid at this moment. The likelihood of proof is just around the corner.

I certainly think its fair to criticize and dissect the logic of unpopular arguments, but we should not make declarations that characterize arguments which have yet to be made before the proof. At this point, I don't see proof which enables us to reasonably quantify how much of the extent reduction is due to ice relocation.
When worldview, bremen concentration maps, hycom and the july piomas agree on the impact of the gaac on melt it cannot be argued, the fact that ess concentration is dropping while in a compaction pattern says it all. Furthermore, denying it would be like denying thermodynamics, temperatures have been reliably above the ice melting point, both air and sst, the insolation is high unabated by the usual clouds and albedo is low. Denying physical phenomenons is also the m. o. of climate change deniers, but beyond that it is just plain wrong, especially with the relative wealth of information provided here


It's amazing it's truly amazing.  We're trying to have an adult conversation centered around dozens+ pieces of scientific data that is aquired through dozens+ pieces of UNBELIEVABLY ADVANCED TECHNOLOGY THAT HAS BEEN TESTED TO NEAR PINPOINT ACCURACY BY THE FINEST SCIENTIFIC MIND OF OUR GENERATION AND THE PREVIOUS TWO.

THIS TECHNOLOGY HAS BEEN TESTED IN THE REAL WORLD FOR DECADE WEATHER IT'S NEW OR OLD IT IS ALL RELIABLE TO NEARLY 100% RELIABILITY.

WE HAVE NO DOUBT ABOUT IT INTERPRETATION AND IN REAL TIME WE CAN PUT IT INTO SCIENTIFIC FACT.


AND YET THIS PRECIOUS FORUM.. WHICH IS A LAST REFUGE... The LAST SANCTUARY WHERE THOUSANDS OF CURIOUS INTELLIGENT WELL UNDERSTOOD AND JOE'S WILLING TO LEARN MINDS OF PROFESSIONALS & AMATURES ALIKE CENTERED AROUND THE BUBBLE OF CLIMATOLOGY METEOROLOGY, GLACIOLOGY, PHYSICAL SCIENCE, PHYSICS, CHEMISTRY, BIOLOGY, ADVANCE MATHEMATICS, CALCULUS, GEOMETRY, ALGORITHMIC MODELING, ALGORITHMIC DATA INTERPRETATION, AND ON AND ON AND ON.. 






AND YET DISSENT RAINS DOWN ONTO THE ASGARD OF ARCTIC SCIENTIFIC GROUP THINK....

TRYING TO WEDGE ITS WAY DEEP INTO THE ESTABLISHED, INFINITLY TESTED WITH EVERY RELIABLE WAY OF UNDERSTANDING THE ARCTIC BIOSPHERE AND IN PARTICULAR IN THIS DISCUSSION MORE SPECIFICALLY THE SEA ICE.





SO YES I AM VERY TRIGGERED WHEN I COME TO THIS SANCTUARY TO READ THE THOUGHTS OF ALL THESE BRILLIANT PEOPLE AND AND INDULGE MYSELF AS DEEP AS I CAN INTO THE DOPAMINIC EXCITEMENT OF NOT ONLY FOLLOWING THE UNPRECEDENTED IN REAL TIME BUT SHARING AND THAT EXPERIENCE WITH THOUSANDS OF BRILLIANT PEOPLE. 


THAT IS CAPPED OFF WITH THE STEADY HIT OF B
THE SEROTONIN SATISFACTION  OF LIVING THIS HISTORICAL REAL TIME TRACKING AND UNDERSTANDING OF AN EVENT.. 


WHICH IS THE FACE...

THE EPITOME...


THE BEAUTIFUL ANOMOLOUS REAL TIME EXPLANATION, THE HOLLYWOOD BLOCKBUSTER THAT IS ONLY SENTIENT SPECIES THE EVER WALK THIS PLANET, AN APEX PREDITOR WHO RULES BE WORLD WITH OVERWHELMING VIOLENCE....

WHILE ALSO DEMONSTRATING THE ABILITY TO ASCEND DISPLAYING UNPARALLELED...

COMPASSION
LOVE
EXPOTENTIAL TECHNOLOGICAL GROWTH...

THE SPECIES OF PHYSICALLY WEAK UPRIGHT WALKING ADVANCED APES UNIQUELY EXISTING AS AN ALONE SINGLE CHILD OF THE HOMINIDS....

YET CARRYING SOME OF THE FABRIC OF ITS NEANDERTHAL SIBLINGS AND DISTANT COUSINS WHO BRAVELY NAVIGATED THE PATH TOWARDS HUMAN ENLIGHTMENT THAT WE ALL GET TO ENJOY...

AND YET WE ARE DESTROYING IT ALL WHILE EXPOTENTIALLY ASCENDING....


AND YET HERE WE ARE:


HAVING TO ACCEPT THAT....

 HUNDREDS OF THOUSANDS IF NOT MILLIONS OF TONS OF ICE HAVE FOUND THE FORCE CAPABLE OF MOVING MILLIONS OF TONS OF ICE OUT OF OCEAN AND ON TOP OF OTHER ICE THAT IS LITERALLY SITTING 1.5-3 METERS AT ITS SURFACE ABOVE THE CLEARING HEIGHT OF THE ADJACENT ICE THAT IS APPARENTLY...

FINDING ITS INNER MICHAEL JORDON...


:)

39
Arctic sea ice / Re: The 2020 melting season
« on: July 17, 2020, 05:03:17 AM »
OH MY GOD. So let me get this straight

The 50+ mile wide strips of 4M+ ice that PIOMAS has incorrectly modeled going back to Spring have maintained themselves through some process where the broken up chunks of one to two meter ice are somehow being flung/thrusted on top of each other over and area that's like 50 to 100 miles wide and 5 times as long?????!

What the ???!


Not to forget the fact that thing entire region has been hit WITHOUT PAUSE by relentless heat and sun.  Phoenix keeps reiterating that temps are EDGIBNG CLOSER TO 0C in GFS land.

TWO THINGS....

1.  The MELTING POINT OF SEA ICE IS ROUGHLY -1.5C TO -1.8C. 

SO SURFACE TEMPS ABOVE 0C ARE ROUGHLY 2C ABOVE THE FREEZING POINT OF THE SEA ICE GOING BACK ALMOST A MONTH. 

SO A MONTH OF RELENTLESS WARMTH AND LOTS OF SUN AND... SOMEWHERE AROUND 6-10 DAYS OF DOWNSLOPING WINDS PUSHING 5-15C TEMPS OVER THE LINCOLN SEA WHICH SAW THE SOUTHERN 2/3RDS OF THE CAB TURN INTO A GIANT MELT LAKE THAT APPEARED ON AMSR2 AS 50-70 PERCENT CONCENTRATION OF ICE UNTIL IT SUBSEQUENTLY DRAINED SHORTLY AFTER.

AND since they drained temperatures have remained well above freezing.

ALBEDO HAS REMAINED VERY LOW. 

THE ICE SURFACE RESEMBLES WET BARE ICE WITH MELT PONDS EVERYWHERE.

THE MODIS REPRESENTATION SHOWS THIS AREA OF UNPRECEDENTED 4M THICK ICE THAT STACKS ONTO ITSELF OVER A REGION THAT IS ROUGHLY 50-100 MILES WIDE AND 5X AS LONG AS BEING TOTALLY SMASHED INTO SMALL, VERY SMALL, AND TO SMALL TO SEE ON MODIS.

OH AND EVEN THO THE WIND HAS BEEN UNIFORM OVER THESE REGIONS NOW VISIBLY LARGE FETCHES OF OPEN WATER.  THAT CONTAINS NO ICE ARE NOW EMBEDDED WITHIN THIS GOLDILOCKS ZONE.

NOT TO FORGET A HUGE 40 MILE WIDE AREA OF OPEN WATER BETWEEN THE COAST AND THE GOLDILOCKS FIELD OF DESTROYED ICE FLOES.

THIS SWATH OF OPEN WATER IS SO BIG AND DEVOID OF ICE THAT MICROWAVE SATELLITE SCANS ARE PICKING UP 1-2 DEGREES C SEA SURFACE TEMPERATURES WITHIN THIS OPEN WATER.

ANOTHER UNPRECEDENTED PART OF THIS MELT SEASON.





TWO MORE POINTS BEFORE I END MY RENT AND APOLOGIZE FOR BEING CONDESCENDING BUT I JUST CANNOT TAKE THIS NONSENSE I COME HERE SO A BUNCH OF REALLY SMART GUYS CAN GET TOGETHER AND TRACK AN UNPRESIDENTED CLIMATE EVENT TOGETHER.  A CAMARADERIE THAT I THOUGHT WAS GROUNDED IN THE PURSUIT OF FACTUAL SCIENCE AND EVIDENCE.  AND YET HERE WE ARE STANDING ON THE SHORES OF THE THINGS WE HAVE NEVER SEEN IN MODERN HUMAN HISTORY ON THIS PLANET. 

AND YET THE SCIENTIFIC PROCESS OF COURSE HAS TO BE S*** ON BY PEOPLE WHO JUST CAN'T COME TO GRIPS WITH REALITY.

THIS SHOW STOPPING B******* JUST MAKES PEOPLE LIKE ME AND MANY OTHERS JUST STOP TALKING AND JUST START TRACKING IT BY MYSELF.

@CSNAVY ABOVE LAID OUT VERY WELL. EXACTLY WHAT HAPPENS WITH THE ISSUE OF SEA ICE AREA AND YET WE HAVE ENDLESS DISCUSSION ABOUT SOME SLOW DOWN IN THIS UNPRECEDENTED EVENT THAT HAS NOT HAPPENED AT ALL.  THERE IS ZERO EVIDENCE OF THIS HAPPENING AND YET IT'S DOMINATING CONVERSATION.


I ALSO WANT TO ADD TWO MORE THINGS PIOMAS IS WRONG.

CRYOSAT IS REAL LIFE MEASUREMENTS.  AND YET IT'S STILL BEING IGNORED FOR SOMETHING THAT IS CLEARLY WRONG.

WHICH IS ONLY BECAUSE OF AGENDA-DRIVEN IDEOLOGY THAT UNDERMINES THE SCIENTIFIC TRUTH THAT SHOULD BE PARAMOUNT HERE.


AND LAST I WOULD THINK THAT IT'S COMMON SENSE THE IDEA OF WEIGHT DISPLACEMENT. 

AND HOW MUCH FORCE WOULD BE NEEDED TO DISPLACE ICE HEAVY ICE ON TOP OF ITSELF OVER SUCH A LARGE AREA WHEN THE ACTUAL ATMOSPHERIC FORCING FROM BELOW IN FROM ABOVE PROBABLY COVERS ABOUT 1% OF THE ENERGY REQUIRED TO MAKE THAT HAPPEN...

AND THE FORCE FROM THE ATMOSPHERE ABOVE AND BELOW IS ALMOST EQUAL EVERYWHERE AND THIS REGION AGAIN SAYING THAT'S NOT POSSIBLE.

ALL RIGHT I'M DONE YOU GUYS ENJOY THIS NONSENSE


40
Arctic sea ice / Re: The 2020 melting season
« on: July 17, 2020, 03:55:16 AM »
So I speculate that the ice thickness may be being maintained due to ice floes stacking on top of each other as they are compacted...

As I replied to you earlier, I see no reason that ice shoves could form over open water (i.e. where no ice is anchored against the coast) during a time of melt. The force required to get one floe on top of the other, while both are moving due to the same weather system in the same general direction would be tremendous. As you yourself said, the ice melts from the edges... the edges of floes during melt season are compromised. I have never seen ice shoves form outside of freeze events, and usually when the temperature is significantly below zero.
While my gut feeling is that floes are too weak to withstand stacking at this time, I recommend reading this recent excerpt from the Mosaic mission, testimony of the tremendous forces resulting from the crazy movement and compaction going on in the CAB in the last few days.

Click to zoom.


41
Arctic sea ice / Re: Albedo-Warming Potential
« on: July 16, 2020, 05:26:07 AM »
This literal interpretation is incorrect. Shallow melt ponds albedo is 0.4 to 0.5 per NSIDC. 0.75 is under the assumption of a low fraction of melt ponds, and the rest snow-covered ice. Bare ice has a lower albedo, and high melt pond fraction combined with deeper melt ponds results in extremely low albedo.

I followed one of the references from sedziobs' link above.
Polashenski, C. M.: Attributing change and understanding melt ponds on a seasonal ice cover, PhD thesis, 2011
Available in full PDF from http://libarchive.dartmouth.edu/cdm/compoundobject/collection/dcdis/id/327893/rec/6

Quote
The variations in integrated shortwave albedo caused by shifts in pond coverage were quite significant. Spatially averaged albedo, calculated from measurements along the transect lines, is plotted in Figure 40c. Prior to pond formation, when the ice surface is snow covered, albedo is relatively stable. Albedo varies between ~0.7 and ~0.8 depending on the age and surface temperature of the snow. As snow melts, exposing bare ice and forming melt ponds, albedo drops significantly and begins to show greater variability. Albedo follows a trend inverse to that of pond coverage. Plotting albedo vs. pond coverage in Figure 40d illustrates the strength of this correlation and helps to confirm that pond coverage is the primary driver of albedo changes on melting ice.
Attached are four images from this source.

42
Arctic sea ice / Re: Fram Export
« on: July 15, 2020, 05:38:52 PM »
Uniquorn posted a wonderful ASCAT animation of the 2019/2020 freezing season. Below is my attempt to delineate areas of export since the September 2019 minimum by tracking features.

Red exits the Fram, blue into the Barents Sea, yellow into Nares Strait, and green into McClure Strait. It wasn't a very active season for Nares or the garlic press.

For me the takeaway is that melt in the Pacific and American sectors is much more consequential for multi-year ice than how far the ice edge retreats on the Atlantic or Laptev fronts.

43
Arctic sea ice / Re: The 2020 melting season
« on: July 14, 2020, 03:31:47 AM »
This is where I think the minimum will be.

The thinner white line it's my operational prediction.

The hazy white is where I see potentially low concentration  ice left.

I feel very confident about this.   And that's crazy.   

44
Arctic sea ice / Re: The 2020 melting season
« on: July 08, 2020, 06:20:53 PM »
The past 3 days have been as destructive to the ice as any three days I have watched including the GAC. The creation of extensive melt ponds across the ice of the high Arctic has happened and the transmissivity of the ice to visible radiation has been increased by the weather. Cooler temperatures will not undo that.

The GAC was destructive because it persisted for about 10 days and mixed up warmer saltier water from below. However, there was one benefit to sea ice of the GAC. The ocean lost heat to the atmosphere. This high pressure over the pole in the beginning of July is adding heat to the central Arctic ocean at an extraordinary rate. The anticyclonic spin of the ice pack under the high is also pulling warm water into the Arctic from both the Atlantic subarctic seas and the Bering strait. As long as the high pressure keeps on spinning the warm water will keep on getting pulled in and the ice will melt at an above average rate.

45
Arctic sea ice / Re: The 2020 melting season
« on: July 05, 2020, 12:53:23 PM »
Сan see how quickly the large ice floe of fast ice 30 km in size disappears into the Laptev Sea.

46
Arctic sea ice / Re: HYCOM vs ASMR2 Imagery
« on: June 25, 2020, 09:44:02 PM »
and the rest. It should be noted that 2014 image was later in the year than the rest.

47
Arctic sea ice / Re: HYCOM vs ASMR2 Imagery
« on: June 25, 2020, 09:41:41 PM »
Just a comparison for this time of year.

48
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: June 25, 2020, 06:46:16 AM »
In lieu of Juan's update.

[ADS NIPR VISHOP (JAXA)] Arctic Sea Ice Extent.

June 24th, 2020:
     9,436,977 km2, a drop of -100,451 km2.
     2020 is 2nd lowest on record, 105,126 km2 behind 2016.
Thanks wdmn  :)

[ADS NIPR VISHOP (JAXA)] Arctic Sea Ice Extent.

June 24th, 2020:
     9,436,977 km2, a century drop of -100,451 km2.
     2020 is 2nd lowest on record.
     Highlighted 2020 & the 4 years with a daily lowest min in Sept. (2012, 2019, 2016 & 2007).
     In the graph are today's 15 lowest years.
     Source: https://ads.nipr.ac.jp/vishop/#/extent

49
Permafrost / Re: Permafrost general science thread
« on: June 17, 2020, 06:45:43 AM »
Article about the research in #96:

https://e360.yale.edu/digest/climate-models-underestimate-co2-emissions-from-permafrost-by-14-percent-study-finds

Scientists estimate there are about 1,500 billion metric tons of carbon locked away in Arctic permafrost, and that 5 to 15 percent of this carbon could be emitted as carbon dioxide by 2100 — enough to increase global temperatures 0.3 to 0.4 degrees Celsius. But these estimates do not include the CO2 that forms when permafrost carbon escapes into Arctic lakes and rivers and is oxidized by ultraviolet and visible light, a process known as photomineralization.

Researchers at the University of Michigan studied organic carbon from six different Arctic locations and found that substantial carbon dioxide emissions could be released through photomineralization — enough to raise permafrost-related CO2 emissions by 14 percent.
...
“Only recently have global climate models included greenhouse gases from thawing permafrost soils. But none of them contain this feedback pathway,”


50
The rest / Re: George Floyd murder and blowback
« on: June 04, 2020, 01:29:15 AM »
The military is choosing sides ...

James Mattis Denounces Trump as a Threat to the Constitution
https://www.defenseone.com/ideas/2020/06/james-mattis-denounces-trump-threat-constitution/165891/

In an extraordinary condemnation, the former defense secretary backs protesters and says the president is trying to turn Americans against one another.

James Mattis, the esteemed Marine general who resigned as secretary of defense in December 2018 to protest Donald Trump’s Syria policy, has, ever since, kept studiously silent about Trump’s performance as president. But he has now broken his silence, writing an extraordinary broadside in which he denounces the president for dividing the nation, and accuses him of ordering the U.S. military to violate the constitutional rights of American citizens.

“I have watched this week’s unfolding events, angry and appalled,” Mattis writes. “The words ‘Equal Justice Under Law’ are carved in the pediment of the United States Supreme Court. This is precisely what protesters are rightly demanding. It is a wholesome and unifying demand—one that all of us should be able to get behind. We must not be distracted by a small number of lawbreakers. The protests are defined by tens of thousands of people of conscience who are insisting that we live up to our values—our values as people and our values as a nation.” He goes on, “We must reject and hold accountable those in office who would make a mockery of our Constitution.”

In his j’accuse, Mattis excoriates the president for setting Americans against one another.

Quote
“Donald Trump is the first president in my lifetime who does not try to unite the American people—does not even pretend to try. Instead, he tries to divide us,” Mattis writes. “We are witnessing the consequences of three years of this deliberate effort. We are witnessing the consequences of three years without mature leadership.

He continues, "We can unite without him, drawing on the strengths inherent in our civil society. This will not be easy, as the past few days have shown, but we owe it to our fellow citizens; to past generations that bled to defend our promise; and to our children.”

He goes on to contrast the American ethos of unity with Nazi ideology. “Instructions given by the military departments to our troops before the Normandy invasion reminded soldiers that ‘The Nazi slogan for destroying us … was “Divide and Conquer.” Our American answer is “In Union there is Strength.”’ We must summon that unity to surmount this crisis—confident that we are better than our politics.”

Mattis’s dissatisfaction with Trump was no secret inside the Pentagon. But after his resignation, he argued publicly—and to great criticism—that it would be inappropriate and counterproductive for a former general, and a former Cabinet official, to criticize a sitting president. Doing so, he said, would threaten the apolitical nature of the military. When I interviewed him last year on this subject, he said, “When you leave an administration over clear policy differences, you need to give the people who are still there as much opportunity as possible to defend the country. They still have the responsibility of protecting this great big experiment of ours.” He did add, however: “There is a period in which I owe my silence. It’s not eternal. It’s not going to be forever.”

That period is now definitively over. Mattis reached the conclusion this past weekend that the American experiment is directly threatened by the actions of the president he once served. In his statement, Mattis makes it clear that the president’s response to the police killing of George Floyd, and the ensuing protests, triggered this public condemnation.

“When I joined the military, some 50 years ago,” he writes, “I swore an oath to support and defend the Constitution. Never did I dream that troops taking that same oath would be ordered under any circumstance to violate the Constitutional rights of their fellow citizens—much less to provide a bizarre photo op for the elected commander-in-chief, with military leadership standing alongside.”

He goes on to implicitly criticize the current secretary of defense, Mark Esper, and other senior officials as well. “We must reject any thinking of our cities as a ‘battlespace’ that our uniformed military is called upon to ‘dominate.’ At home, we should use our military only when requested to do so, on very rare occasions, by state governors. Militarizing our response, as we witnessed in Washington, D.C., sets up a conflict—a false conflict—between the military and civilian society. It erodes the moral ground that ensures a trusted bond between men and women in uniform and the society they are sworn to protect, and of which they themselves are a part. Keeping public order rests with civilian state and local leaders who best understand their communities and are answerable to them.

Here is the text of the complete statement: ...

https://www.cnbc.com/2020/06/03/read-mattis-statement-on-trumps-handling-of-nationwide-protests.html

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