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Messages - oren

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1
Science / Re: Where are we now in CO2e , which pathway are we on?
« on: January 21, 2021, 10:16:31 PM »
Just in addition to my previous post I want to confirm that the increase of CO2eq from these four "NOAA gases" is of slightly exponential nature, although the calculation of the radiative forcings has a square root function in it (a four fold increase of CO2 means a doubling of additional radiative forcing). I doubt that this behaviour is compatible with a RCP2.65 path.

See attached picture.

2
Science / Re: Where are we now in CO2e , which pathway are we on?
« on: January 21, 2021, 09:20:45 PM »
Ken,
please remember that I only cover the "NOAA gases" (CO2, CH4, N2O, SF6) that are regularly reported about on the NOAA website (https://www.esrl.noaa.gov/gmd/ccgg/trends/index.html). There are other (and not too unimportant) greenhouse gases like chlorinated and/or fluorinated hydrocarbons which must be added to the list which make the real CO2 eq higher than I calculate it.
There are some posts about this, including figures and graphs, further up in this thread.

I am no expert in judging the effect of black carbon, soot, aerosols, land use change etc on the CO2eq evaluation so I can not comment this part of your post.

kind regards from Germany Stephan

3
Consequences / Re: Global Surface Air Temperatures
« on: January 20, 2021, 06:47:29 PM »
Claims to be not a denier.
Cherry picks one outlaying data set.
Only UHA gives 0.14.
All the others give 0.19C a decade or more.
https://skepticalscience.com/trend.php
Still claims we can have a hiatus in warming by looking at  noise.
It is the trend stupid .
Global warming  is the long term trend not the yearly weather fluctuations.

4
The forum / Re: Forum Decorum
« on: January 19, 2021, 12:10:24 PM »
One thing is to discuss things in your armchair about upcoming problems in the future (AGW, ice-free arctic). Another thing is to discuss about problems that directly influence your life (i.e Covid). The problem is that people are afraid of death, and despite facing ecological collapse people are not adapted to the idea of dealing with actual collapse in personal lives.

As the climate crisis deepends, in addition to Covid we would get a variety of different discussions with people in panic. Be it poverty, economic crisis, political crisis, uprising, wars, hunger, etc. People lose their mind when they are personally involved in them. As mentioned, it's far easier to discuss about problems in your armchair, when they are still distant. But the issue with AGW is that at some point all compounding problems will reach everybody personally.

So my only suggestion for everyone is to reflect on the ecological catastrophe and make peace with the fact of annihiliation and death that planet Earth has decided to give us (and every other living creature) as we humans have exceeded the planetary carrying capacity with our consumption. Use the time left in your lives to reflect and still learn something useful. Either skills or philosophical conclusions about living a life. Don't be afraid or scared of problems, when they are coming, because in the grand scheme of things they are supposed to happen anyway. These problems are just an important lesson to learn. Living a life as a human being is a temporary experience anyway, for every single soul out there. Use that relatively short time on a cosmic scale to learn something valuable.

5
The politics / Re: The Media: Examples of Good AND Bad Journalism
« on: January 19, 2021, 07:22:14 AM »
Colour me unsurprised: google and facebook collude on ads

Wakabayashi and Tsu at nytimes:

"Google and Facebook accounted for more than half of all digital advertising spending in 2019"

"In the milliseconds between a user clicking on a link to a web page and the page’s ads loading, bids for available ad space are placed behind the scenes in marketplaces known as exchanges, with the winning bid passed to an ad server. Because Google’s ad exchange and ad server were both dominant, it often directed the business to its own exchange."

"A method called header bidding emerged, in part as a workaround to reduce reliance on Google’s ad platforms."

"Google developed an alternative called Open Bidding"

"Facebook disclosed that it had joined Google’s program in one line in a Dec. 2018 blog post. But it did not reveal that Google, according to the draft complaint, provided Facebook with special information and speed advantages to help the company succeed in the auctions that it did not offer to other partners — even including a guaranteed “win rate.”

"Facebook had 300 milliseconds to bid for ads, according to court documents. But the executives at Google’s partner companies said they usually had just 160 milliseconds or less "

"Facebook had yet another advantage: Direct billing relationships with the sites where ads would appear"

"Google agreed to help Facebook have a better understanding of who would be shown the ads by helping the company identify 80 percent of mobile users and 60 percent of web users"

"Facebook also demanded that data about its bids not be used by Google to manipulate auctions in its own favor"

“Unbeknown to other market participants, no matter how high others might bid, the parties have agreed that the gavel will come down in Facebook’s favor a set number of times,”

"they included a clause in the agreement that requires the parties to “cooperate and assist” each other if they are investigated for competition concerns over the partnership."

https://www.nytimes.com/2021/01/17/technology/google-facebook-ad-deal-antitrust.html

I happen to have watched some of this happen, the adexchanges and bidding platforms get set up, and i still have friends in that biz. It don't really surprise that goo and face were colluding, we kinda assumed it anyway and you could see it in the timings for ad auctions. But i dunno whether to laff or to cry at this:

"Facebook also demanded that data about its bids not be used by Google to manipulate auctions in its own favor"
 
Dude, when you gotta put a clause in a contract that sez dont cheat on this contract, mebbe you shouldnt be signing the contract to start with. And i cant believe Zuckerburg thought google would actually abide by any contract, they screwed everyone else.

sidd

6
Consequences / Re: Global Surface Air Temperatures
« on: January 18, 2021, 10:02:16 AM »
Quote
Might we call another global warming hiatus?

You could.
But you would just be confirming  you are a scientifically illiterate denier of reality .

For those of us with some idea .
Interesting new post on real climate looking at the last years global temperatures including the influence  of  ENSO
   http://www.realclimate.org/index.php/archives/2021/01/2020-hindsight/

7
Antarctica / Re: Pine Island Glacier (PIG) Calving and Discussion
« on: January 17, 2021, 07:41:51 PM »
Calculation of the PIG speeds from the data on the site: http://www.cpom.ucl.ac.uk/csopr/iv/index.php?glacier_number=3 for the months of June and December, from December 2014 to December 2020.

Averages used:
To avoid problems related to doubtful variations in the measurements provided between close points along the transect for the same period and between close intervals for the same position along the transect I calculated the average of the existing measurements for :
> the same interval of points along the transect: 20-30 km, 30-40 km, ..., 120-130 km (I considered that the measurements of the other intervals:  > 130, did not provide sufficiently reliable measurements)
> 5 periods for each month of June and December. For the month of December 2016 and for all months starting in December 2017 we have files that calculate the speeds from intervals of 6 days that follow each other regularly (which makes a global interval of 36 days).This is no longer true for the months prior to December 2016 and for the month of June 2017; in these cases I took the 5 periods closer to the month of calculation, with, as a result, an overall interval between 42 and 108 days and with overlaps between the periods used for the velocity calculations. Moreover for the months of June 2015 and 2016, for one of the chosen intervals I find no valuation of the speed and for these two months I calculate the speed using in reality only 4 intervals.  For the month of December 2015 I find no valuation for the points between 20 and 30 km.

Sources of speed valuations along the transect:
> for the period 2014-2019 I based myself on the text files containing the valuations per point and per period, files contained in the global zip that I downloaded. 
> For the month of June 2020 I am based on the individually downloaded text files.
> for the month of December 2020 no text files are available and I based on the image of the downloaded diagram to value the speeds by interval: 20-30 km up to 60-70 km and I dropped the other intervals for which a reliable valuation was not possible (in the first image I give an example of the images used for my valuations)

Results :
> The measures found are presented in the second image and it can be seen that they are consistent with each other.
> There is indeed a more or less constant acceleration from June 2018. To bring it out more clearly I calculated the averages for the 20-70 km interval that I show in the third image.

Click to enlarge

ADD : In the third image it is the average over the interval 20-70, the values for the interval 20-30 are higher, e.g. for December 2020 there are 4.816!

8
Arctic sea ice / Re: 2021 Sea ice area and extent data
« on: January 15, 2021, 04:48:55 AM »
[ADS NIPR VISHOP (JAXA)] Arctic Sea Ice Extent.

January 14th, 2021:
     12,943,114 km2, an increase of 63,835 km2.
     2021 is now 8th lowest on record.
     In the graph are today's 16 lowest years.
     Highlighted 2010's average, 2021 and the 5 years with daily lowest minimum:
          (2012, 2020, 2019, 2016 & 2007)

Source: https://ads.nipr.ac.jp/vishop/#/extent.

9
Policy and solutions / Re: Oil and Gas Issues
« on: January 15, 2021, 01:08:58 AM »
Alberta is Canada's most American province.
It reliably elects conservative governments (except when the regular right wing internecine wars rip the Party apart).
It is far and away the largest fossil fuel producer in Canada, and is the single biggest impediment to Canada achieving its climate commitments.
In recent years an otherwise undistinguished blogger called Vivian Krause concocted a conspiracy theory that radical environmentalists were being funded by a sinister cabal of American interests to shut down Alberta's oil and gas industries so that American O&G could reign supreme.
She got considerable traction in the fringes of Alberta's right wing during a period when they were out of power (subsequent to a split between the far right and the extreme right).
When a federal politician moved back into provincial politics and re-united the conservative factions into the currently reigning United Conservative Party, he did so partly by swallowing whole the conspiracy theory, under the assumption that the centrist party that had been in power was insufficiently enamoured of fossil fuels and thus fellow travellers to the foreign funded radicals.
To fulfill an election promise, the new Alberta government funded a public inquiry into 'Anti Alberta Energy Activities', apparently blind to the unfortunate associations between the name of this inquiry and the anti commie inquisition in America in the 1950s.
This public inquiry spent a lot of money commissioning reports that were intended to back up the conspiracy theory.
Today an Albertan law professor who had been asked to review these reports - by the Inquiry- released his take on the reports.
As one might expect, the conspiracy theories did not stand up to scrutiny.
Alberta's fossil fuel industries continue to decline despite this and other (E.G. changing land use designations so that the Rocky Mountains can be turned into open pit coal mines) initiatives.
https://ablawg.ca/2021/01/14/textbook-climate-denialism-a-submission-to-the-public-inquiry-into-anti-alberta-energy-campaigns/

10
Consequences / Re: COVID-19
« on: January 13, 2021, 09:58:44 PM »
Of course there's absolutely no way to know if these "vaccines" help against the mutations.

They'll have to do all new studies on each of these mutations to actually be able to make that statement.

That doesn't stop them from lying, however.  The truth is they have absolutely no idea if the "vaccine" would have any effectiveness against anything beyond what it was tested on and analyzed on.
None of this is true.  Nobody would run a big clinical trial to measure effectiveness of a vaccine against a specific mutation.
Instead, virus inactivation assays are run.  These involve incubating live virus (original and mutant) with serum from fully vaccinated (and non-vaccinated) people.  If the vaccinated serum inactivates mutant virus as effectively as it inactivates the original strain, then this is quite strong evidence that the vaccine remains effective.

No, it's not absolute proof, it's just a persuasive indicator.  We'll know more definitively as vaccine failures accumulate.  The particular strains/variants responsible for these vaccine failures will be studied carefully.

We should not be surprised if some variant arises that is resistant to antibodies produced by the vaccines.  This will indicate the need for multi-valent vaccines, as we use for other infections.

11
Antarctica / Re: Pine Island Glacier (PIG) Calving and Discussion
« on: January 13, 2021, 10:51:38 AM »
A larger version of Ice Velocity from Images Pairs for an overview. Apologies for the fast speed, it's the only way I know how to compress a slow 53MB gif down to 2.1MB. For analysis, best to download it and view frame by frame. (or better, download the original .png files, the ani is half size, cropped)
jul2018-dec2020
The images differ in size by a few pixels so the ani jumps around a bit

I'm quite new to panoply so the third image should be treated with some caution. It focuses on a smaller area from 0-160m. Some of the settings are included in the capture.
x,y coordinate scaling may not be quite right
STD x,y velocity probably not so interesting.

12
Arctic sea ice / Re: The 2020/2021 freezing season
« on: January 13, 2021, 08:56:49 AM »
January 2-12.

2020.

13
Antarctica / Re: Pine Island Glacier (PIG) Calving and Discussion
« on: January 12, 2021, 05:17:09 PM »
I would like to start by posting the images of the "Along-Flow" speeds that can be found in the articles and that give us a good history :
These 4 images are from Rignot 2008, Mouginot et al. 2014, Han et al. 2016, and Jeong et al. 2016 and cover the period from 1973 to 2016.
One can note the gradual acceleration overall, but also strong accelerations (for example in 2001, 2003, 2005, 2006, 2010 and 2014) and temporary slowdowns (for example in 2002, 2011 and 2012).


Click to enlarge

14
Antarctica / Re: Pine Island Glacier (PIG) Calving and Discussion
« on: January 12, 2021, 04:52:36 PM »
Before switching to speeds "Along-Flow" and "Across-Flow" I would like to show the possibilities we have with the data from "MEaSUREs Ice Velocity (Antarctica)" and the applications Panoply and Gimp :
> The first image is given by pasting the 5 images using the following speed intervals: 0-1000 m/yr, 1000-2000 m/yr, 2000-3000 m/yr, 3000-4000 m/yr and 4000-5000 m/yr.During the pasting the colors of the extreme intervals around 1000, 2000, 3000 and 4000 are lost and these zones appear white (you will find the five color scales at the bottom of the image).
During the pasting the colors of the extreme intervals around 1000, 2000, 3000 and 4000 are lost and these zones appear white (you will find the five color scales at the bottom of the image).
> The second uses the 0-250 m/yr scale to highlight the upstream movements of the PIG and these tributaries.

The possibilities opened to us, from these data, to better know the structures of the PIG and these tributaries seem obvious to me.

Click to enlarge

15
Arctic sea ice / Re: 2021 Sea ice area and extent data
« on: January 12, 2021, 05:04:24 AM »
[ADS NIPR VISHOP (JAXA)] Arctic Sea Ice Extent.

January 11th, 2021:
     12,674,081 km2, a drop of -6,442 km2.
     2021 is now 4th lowest on record.
     In the graph are today's 16 lowest years.
     Highlighted 2010's average, 2021 and the 5 years with daily lowest minimum:
          (2012, 2020, 2019, 2016 & 2007)

Source: https://ads.nipr.ac.jp/vishop/#/extent.

16
Greenland and Arctic Circle / Re: The Nares Strait thread
« on: January 11, 2021, 01:12:33 AM »
Yes an interesting read, Gero. (Vox mundi has also posted a link to this Nature article early in this thread).

I do have one gripe.It is an issue that I have seen mentioned on the ASIF several times before - which is how old these papers are by the time they get published.

This paper on Nature Communications was published 4th Jan 2021 and yet has no mention of 2020. The Nares arches were done and dusted by July 2020. 7 months later and no inclusion of the 2020 data. 2017 and 2019 were bad years for arch formation. In 2020 the arch held for approx 200 days, which is more like the longevity arches of old. It is quite likely the arch in 2021 will last over 200 days also.

I have already put a calculation on arch longevity (2007-2020), within the Nares Strait, in post 2448 of this thread. Because of bad years 2017 and 2019 the 5 year average has dropped considerably but 2020 and 2021 will make it rise again (a little).

Like for so much of the Arctic, time is running out for the arches in the Nares. I was surprised that for both 2020 and now 2021, arch formation has begun relatively early. Whilst the Nature Comms article is a good read. It is not up to date.   

17
Antarctica / Re: Thwaites Glacier Discussion
« on: January 10, 2021, 07:13:53 PM »
As a comparison with last year, here is the land-fast sea ice off of Thwaites Tongue from March 23-25, 2020, with the discussion at:
https://forum.arctic-sea-ice.net/index.php/topic,1760.msg256340.html#msg256340

As it turns out, the sea ice began refreezing in early April 2020, so nothing significant came from that break-up.

The previous year, 2019, was a different story.  The earliest image I have from February 16, 2019, shows the area almost completely free of sea ice.  Shortly afterwards, most of the icebergs at the lower right side of the image floated off en masse.

It sure looks like 2021 will be worse than 2020 (at least in this part of the Antarctica) but too soon to say if comparisons with 2019 are warranted.

18
Antarctica / Re: Thwaites Glacier Discussion
« on: January 10, 2021, 07:06:24 AM »
I've noticed a recent increase in movement of Iceberg B22-A recently, so I thought I would give an update.  I post about B22-A here instead of the Iceberg thread because it is still close enough to Thwaites to affect the sea ice that helps to stabilize Thwaites to some extent.

The GIF below shows the movement of B22-A over the past 22 months.  It can be separated into three phases: 1) March 2019 to April 2020, Northward Movement; 2) April 2020 to October 2020, Westward movement (with calving from the western end); and 3) October 2020 to January 2021, Northward movement again.  All three phases resulting in approximately the same distance moved, so you can see that the velocity just about doubled between each phase (12 months to 6 months to 3 months.)  It is this increase in speed that is most concerning.

There is some rotation during this movement, but it hasn't resulted in a pattern yet.  Alternating between clockwise and counter-clockwise rotation, the orientation hasn't changed much over time.

The second image shows three areas of shallow water that tend to keep B22-A in place.  A peak on the eastern end, shallows on the western end, and another shallow to the Southwest near Bear Peninsula.  One concern is that the recent calving from the older Western end of the iceberg may allow it to rotate away from the shallows.  Of course, further movement to the West could also free it from the Eastern Peak.

The bathymetry under B22-A has never been accurately mapped, so it is hard to make predictions.  But observing the motion over time give us clues to where the iceberg is grounding and how it might float off, or at least float far enough away to change the sea ice off of Thwaites and neighboring glaciers.

19
Arctic sea ice / Re: Home brew AMSR2 extent & area calculation
« on: January 09, 2021, 05:21:19 PM »
Kara Sea.
Compilation of AWI v103, SMOS and Mercator salinity at 34m, oct28-jan8.
Some interference in the Barents on SMOS. Some small colour changes in compilation so the scales are a rough guide

AMSR2 3.125 data from Wipneus. Kara not quite reaching the dip of 2017 yet.

20
Consequences / Re: Origins of COVID-19
« on: January 06, 2021, 12:57:06 AM »
This reminds me of the old lawyer trick when they have a guilty person and they want to get them off the crime.

First you are presented with overwhelming evidence, then the lawyer starts to throw 1001 different unlikely scenarios that could have, maybe, possibly happened to explain alternative reasons for the crime to have happened.

Sure, it is unlikely that an asteroid landed on the house and burnt it down, sure it is more likely to be matches, but you cant 100% rule the asteroid theory out.

Do that often enough from multiple sources, and eventually people will latch onto one of those theories and then they start saying "where there is smoke, there is fire" and then you have a total bullshit line of theories that amount to nothing on their own, becoming something that creates enough doubt in people's minds to think, yeah, it is possible it was a lab escape or experiment or deliberately done..... in spite of the part where the most likely one or two stories are actually correct.

And that is when we get 1001 weird stories having more value than 1 or 2 truths.

It would be nice for someone to produce something that shows us that the lab was responsible for this, rather than a series of unlikely events or blaming gaps in knowledge as the reason they think it was man made.

21
Consequences / Re: Origins of COVID-19
« on: January 05, 2021, 06:17:09 PM »
Just going by the principle "Extraordinary claims requires extraordinary evidence"

One article by two dudes who are at best at the outer margins of their fields and not active researchers does not raise to that standard.

But you've clearly already decided you know the absolute truth about this, so don't let me get in your way! :)

22
Consequences / Re: Origins of COVID-19
« on: January 05, 2021, 07:06:52 AM »
For John Palmer and Harpy, please stop publishing BS about the virus origin. I know it would be reassuring if it was produced by humans, because it would means that with a better control of humans, we would be on the safe side, that we don't need to change our way of life.

Pandemic viruses are a normal evolution, because mutations happens all the times, but most of the mutations can be controlled directly by our body, some can be controlled by our health care system, and once in a while, like every 100 years, probably even less, there is one mutation that just can't be stopped.

Our globalization makes it worse because we mix our populations constantly, if the plague took years to go to most part of the world, few weeks were enough for the Covid19. Furthermore, using each piece of land available on earth is like searching for forgotten viruses.

Until Covid19, we have been very lucky that other viruses like Ebola didn't go all over the world.

23
Antarctica / Re: Halley base shut down and new crack in Brunt shelf
« on: January 04, 2021, 06:58:12 PM »
Animated comparisons of today's clear sentinel images, and almost one year ago. Click to play.

The main rift has widened significantly, but not lenghtened very much, even filled back with snow at the edge it looks like.. However, the smaller rifts coming to meet it from the north *have* lengthened some.

24
Arctic sea ice / Re: What the Buoys are telling
« on: January 02, 2021, 06:43:04 PM »
Uniq et al have been able to effectively color buoy tracks by speed, with direction implicit as tangents to the displacement line. This is a lot easier than calculating velocities from persistent features in Ascat pairs. Buoy tracks are just one dimensional though so it takes a lot of them to get an overall coherent picture of ice movement even if delaunay triangulation is feasible.

OsiSaf provides Arctic-wide velocities, though these are 48-hour vs 1-hour for buoys. neXtSIM provides separate x,y velocity maps over its ice thickness animation without really explaining the axes nor providing any means to combine them into vectors (though this feature has be requested by T. Lavergne).

The two animations below look at the x,y coordinates in a split palette as provided by Cmems/Lobelia. Here the reddish color is positive and the bluish negative. It seems that the Greenwich meridian and north pole may define the x axis, with the y being orthogonal in flattened view.

The second mp4 overlays OsiSaf arrows in an effort to make some sense of the Cmems product as currently provided. The avi for that is attached for those wanting to study individual frames.

The third mp4 tests the hourly setting at the CMEMS gif generator. The 73 frames are run at 20 fps, much faster than the mp4 above. Here they need a menu option for 3,4, 6, and 12 hours.

Technical note: The 'interleave' setting on 'stacks' --> 'tools' in ImageJ is key to interdigitating pairs of stacks, followed by doubling down on montage width framing.

25
Arctic sea ice / Re: The 2020/2021 freezing season
« on: January 02, 2021, 03:07:36 PM »
2020 extent at 2 week intervals, split into the freeze, melt, freeze periods.

Will add the gradual concentration change for the whole year in a day or 2

(large file, click to play)

26
Arctic sea ice / Re: The 2020/2021 freezing season
« on: January 02, 2021, 12:10:16 PM »
A comparison of 2017, 2018 and 2020 freezing seasons using amsr2-uhh

27
Arctic sea ice / Re: What the Buoys are telling
« on: January 01, 2021, 05:37:44 PM »
Quote
hopefully can finalize mid-90's, update the formats and standardize map orientation
Amazing to me how many sites still refuse to cooperate with NSIDC, NASA and AWI/Hamburg/Bremen. These +45, -45, -135 rotations cannot be done as matrix transpositions in the manner of n90 and so alignment inevitably degrades data quality. About 2/3 of the archives are still refusing to provide the underlying numerical netCDFs at all or as open access or in a Panoply-compatible format, though it is just a single unix command line for the source. NOAA-PSL and Climate Reanalyzer won't even use the two agreed-upon projections, polar stereographic 70º and equal area azimuthal EASE2. There are no online tools to interconvert (lacking Geo2D netCDFs); scales and ESPG projection parameters aren't even given.

Climate emergency hasn't been enough to induce cooperation across silos.

The neXtSIM archive currently runs 860 days from 01 Nov 2018 to 07 Jan 2021. As a gif, this runs to 250MB (after cropping down from 2.1GB to the Arctic Basin), still 50x too large for the forum though handled seamlessly at any playback speed on any platform by ImageJ freeware, a thirty second download-install that few here will do. Saved as an avi, the file size drops to 12MB which converts to a forum-friendly 4MB mp4.

The CMEMS neXtSIM archive shows Arctic Ocean sea ice motion very clearly and likely quite accurately given daily satellite assimilation and developed model. Promised, with no firm timeline, is neXtSIM imagery back into the early satellite record.

That will resolve a huge issue for us: continuity of ice feature tracking during the cloudy summer when so many of the visible, infrared and microwave products are incapacitated by moisture artifacts or lack of coverage. Articles generally cite DMSP SSM/I-SSMIS for summer months but that 25x25 km data, at least at NSIDC, is not available anywhere as an image archive.

https://nsidc.org/data/ssmr_ssmi/news.html
https://nsidc.org/ancillary-pages/smmr-ssmi-ssmis-sensors

Below is the entire current record from CMEMS neXtSIM. It provides two complete summers, three Nov-Dec fall freeze-ups, the entire Polarstern year, and seven days of marginally informative forward projection. This is a good resource for characterizing TransPolar Drift variation and Beaufort Arm development (no gyre occurs nor is in formation).

On the technical side, it is difficult to simultaneously optimize display of FYI and MYI. Here the palette squeeze, originally on grayscale, was 0 to 3m. It might be feasible to run the animation request twice, at 0-1m and 1-3m and overlay since we are not interested in actual Topaz4 ice thickness numbers, any more than Ascat sigma-0 brightnesses. As noted previously, the Lincoln Sea is modelled way thicker than it actually is; to accommodate its value would seriously degrade the contrast range of the rest of the ice.

28
Antarctica / Re: Pine Island Glacier (PIG) Calving and Discussion
« on: December 30, 2020, 01:20:49 AM »

Paolo
If I understand things initially you were saying that t11 was contributing significant side pressure as shown in A with significant side pressure somewhere in the middle of the southern shear margin. With arrow length roughly represent pressure. I was thinking that elevation of the southern shear margin indicated the greatest side pressure was near the ice edge and was smaller further away from the ice edge. This is represented by shortening arrows. My diagram does not show that I didn't think this side pressure was very significant. After reading an article on the effects of damage on the southern shear margin that t11 is not (as I thought) providing significant to the main flow. When the pig was flowing slower the side pressure on the shear margin was such that the main flow did not exceed the strain rate. At that time the ice sheared at the shear margin. Something changed and the velocity of the main flow increased enough to exceed the maximum strain rate resulting in tears perpendicular to the shear margin. These tears became the damage zone. The damaged shear zone provides substantially reduced resistance to the main flow because the ice no longer has to shear ice on that side. Further the main flow ice on the shear margin side is free floating. A number of other parameters also influence the main flow rate but sorting out which is cause and effect is difficult.
An interesting article on the subject https://www.pnas.org/content/117/40/24735

29
Arctic sea ice / Re: Arctic Image of the Day
« on: December 30, 2020, 12:28:27 AM »
I thought this one worthy of the forum

30
Arctic sea ice / Re: The 2020/2021 freezing season
« on: December 29, 2020, 01:27:33 PM »
Fall freeze up to date, emphasis on MYI.

31
Antarctica / Re: Thwaites Glacier Discussion
« on: December 27, 2020, 10:05:31 PM »
Just a quick and dirty GIF of the calving front versus almost 2 years ago.  Not seeing much a retreat.

32
Arctic sea ice / Re: The 2020/2021 freezing season
« on: December 27, 2020, 05:48:07 PM »
Below is a quick wrap of the effect of the 08-26 Dec 2020 basin-wide anti-cyclone for the Lincoln Sea / Ellesmere Island area. (The effect on the Beaufort ice is shown over at the Mosaic forum.)

This is something we have seen many times before: the wind would like the ice to rotate with it about the center of the anti-cyclonic high but the shape of the Arctic Ocean basin is too small and asymmetric to accommodate CW rotation of the necessary diameter.

The ice then hits an unmovable object -- northernmost Ellesmere Island in the Cape Columbia / Ward Hunt Island / Cape Discovery area and shears repeatedly into very long arcs. In late December, the ice in the Lincoln Sea responded to stress by shearing transversely to the existing leads (inset on geology map), much like faulting in California earthquakes.

There's probably no long-term significance locally; it won't affect later opening of the Nares Strait and ice export. However, like MYI boundary tracking with the white band, it's part of understanding overall ice motion in the Arctic which is increasing as weaker FYI comes to dominate the overall ice pack.

The timing of ice disappearance cannot be figured from thermodynamics alone as ice breakup, swell damage, advection to warmer seas, and export out of the basin will play large roles in the end game. It looks now that 'Siberian side semi-BOE' will be a key intermediate because Arctic Amplification, Siberian weather and encroaching Atlantification are favorably asymmetric in that sense.

33
Arctic sea ice / Re: The 2020/2021 freezing season
« on: December 27, 2020, 01:57:08 PM »
Quote
white band: previous years yes/no/, where/when, other satellites
These are all useful avenues of investigation. The white band is not somehow 'inevitable' in C-band radar -- no one predicted its existence and no journal article describes or explains it, possibly because Ascat is seriously under-utilized and Sentinel-1AB is fairly new.

Looking back, the white band first appears in the Ascat archive at the end of August near the end of melt season at the seasonal marginal ice zone (MIZ), the transition zone between the ice pack and open Arctic. That cannot be the whole story because the Pacific half of the potential boundary zone doesn't form the white band. Some other tracker is needed there to mark the shape-shifting division between FYI and MYI ice over the freeze season.

The white band is initially far more extensive, forming a border from below the New Siberian Islands all the way around to Svalbard. Only the Laptev portion persists; the Atlantic side is still very subjected to wind effects in late December (uniq's AMSR2 gif above).

In the satellite archives we use, the visible is fairly literal (corrected reflectance) as is the infrared (offered in various false color palettes), not that different from the view out an airplane window with appropriate goggles.

Looking at Nasa's WorldView, there wasn't a clear enough day over the time and location window to determine whether or not the white band is visible at these wavelengths. The white band is not an open lead or polynya so not brighter/warmer in Suomi band15 infrared.

It is no coincidence that  Ascat and Sentinel-1AB both see the white band: they observe at very similar wavelengths of 5.7cm and 5.5cm (5.255 and 5.405 GHz, C-band in radar WWII terminology). Sentinel-1AB resolves much greater detail but coverage is episodic and difficult to tile.

The question is, can the white band be seen on the ground, with instrumented airplane flyovers, or in L-band or other radar products? In other words, the band's electromagnetic reflectance spectrum is key to determining what it is (or at least ruling out what it is not).

Microwave products like Smos are brought into visible 8-bit interpreted products after extensive processing algorithms. Smos looks at a longer wavelength of 21.4cm(1.4 GHz L-band) and can measure distance through the ice (of a half meter or less thickness) to sea water. The white band is not apparent; note though the archive provides only the highly processed view.

The white band cannot be seen in AMSR2, CMEMS, Piomas, Hycom, OsiSaf, SicLeads, Smap, Smos-Smap, Jaxa, cryosat2smos or other products.

Ascat brightness diminishes rapidly with near-surface ice and atmospheric path polarity (dielectric); older ice is farther along in brine exclusion so whiter. However this is not a good fit to the white band along the former MIZ unless that ice is somehow so crumpled that brine channels have already drained. Other forms of elastic scattering can relate to surface roughness or particle size relative to incident wavelength.

Only Ascat sticks to a literal beam reflectance (grayscaled 0-1 or σ⁰ backscatter, lower left corner scale in files). It was never intended for ice; the primary instrument justification has been ocean surface wind speed measurement at mid to low altitude.

We discovered here years ago that Ascat holds hidden treasures: after a series of photoshop-type contrast enhancements, the initially bland imagery can accurately display ice movement as well as regions of brine exclusion maturity (older thicker ice) and other persistent but unexplained interior features. There is no use of Ascat enhancement in the Arctic science community.

Yesterday's before and after are shown below, with emphasis on MYI. Movement of many of the ice substructures can be tracked for months, sometimes deforming but still persisting in time series, so not processing artifact. Click to see at full scale.

There's a lot more going on with the ice pack than just one-parameter thickness.

34
The forum / Re: Merry Christmas everyone.
« on: December 26, 2020, 02:59:51 AM »
Our Christmas was different:  We cooked for each other (2 of our kids, separately, and us) and exchanged containers for eating later.  A pair and a trio (including partners) visited for 1/2 hour spells, all always masked (one set with a porch screen between us and jackets on).  It felt Christmasy as we had a slight frost this morning (2/10 of a degree F!), colder tonight.

I remember my 1972 Christmas in Sydney.  They were having a hot spell (40C).  Bondi Beach was beautiful, but the sand was too hot to stand on and a shark kept us on the shore...  Christmas dinner (made by Aussies) was 'everything we were used to, only cold'.

One Christmas in NZ I hitch hiked from Dunedin northwards.  I hoped to get to Christchurch, but went way further.  Lots of mostly short rides (14, IIRC) and seldom even 5 minutes between them. Nobody, it seemed, wanted to leave a stranger on the road. The first ride was from a nurse taking presents to patients at the mental health hospital just north of town and the last was with a family coming from Dinner (capital "D") with the wife's family and headed for Dinner with the husband's.  That man sure did talk, and he described every dish they'd had and the specialties he was looking forward to.  (Wife and 2 kids were silent.)  I never told anybody that day that I was fasting; it was easy to be with my hosts in their various styles of joy and thanksgiving.  It was a truly blessed day for me!  It ended 'early' as I was left off at a totally rural highway intersection, and I decided to stop.  Beside the road was a copse of trees in which I camped, and a large stream/small river, cobble-bedded.  I meditated in the stream (seated, with water up to my mid-chest) for an hour or so, during that sunny endless summer evening.

I know, it's Boxing Day now for most of you!

Find (and share) the blessings,
Tor

35
Antarctica / Re: Pine Island Glacier (PIG) Calving and Discussion
« on: December 25, 2020, 08:15:35 PM »
There has been a lot posted here about the Southern Ice Shelf, so I thought I would review recent developments and the implications for Pine Island Glacier.

First is a 30-day GIF of the developing rifts on the Southern Ice Shelf.  Movement has been pretty much continuous, so it would appear that a significant calving is becoming imminent.

The Southern Ice Shelf (SIS) is being pushed from the West by the Southwest Tributary (SWT) and supports the "T11" Tributary as it is merges with the main trunk of the Pine Island Glacier (PIG.)  Ever since the PIG Ice Front retreated from its merger with the SWT, the SIS has been weakened by rifts and calving.  The danger is that the loss of SIS will weaken T11.  In particular, the current SIS rifts (red) could extend to the T11 (orange) leading to more calving at the end of T11 (yellow.)

Even a temporary retreat of T11 could lead to the upstream rifts in the Southern Shear Margin (SSM) spreading downstream and which could speed up and weaken the PIG.  Further retreat of the PIG ice front could result in a permanent disconnect between the PIG and T11 just as has occurred with the SWT.

This could also affect the Northern Shear Margin (NSM) if the loss of contact with T11 causes the NSM to pull further away from the stationary Evans Knoll grounding line.

36
Arctic sea ice / Re: What the Buoys are telling
« on: December 24, 2020, 05:42:15 PM »
Haversine formula (first)

vs

Pythagoras (second)

The data is raw (unsmoothed). The Haversine data is extremely positively skewed, there are clearly many errors (I am sub-sampling about 7,000,000 data points so it will happen). But importantly its possible to make out seasonal variability in Haversine, which makes me believe it more

Also uniquorn just clearly explained why not to use Pythagoras for this

Interpretations and questions:
Can we make an interpretation?
Can we identify any predictors by looking at drift speed?
Has this already been covered before in publication?

Ill continue to work on smoothing and add 2016-2020 (they changed the data format slightly so I cant batch it)






//////////last file is smoothing applied to Central Arctic Basin haversine velocity

37
Arctic sea ice / Re: The 2020/2021 freezing season
« on: December 24, 2020, 01:53:48 PM »
CS2SMOS merged SIT oct16-22 to dec14-20. An attempt at measurement rather than modelling.

38
Arctic sea ice / Re: What the Buoys are telling
« on: December 23, 2020, 05:57:52 PM »
This is very interesting work you're doing, Simon!

Is this graph saying that ice (as recorded by buoys) moves in some regions at a fairly steady pace while in the CAB it moves slowly to quickly?  Watching A-Team's movies, doesn't the ice stop moving sometimes - i.e., it moves in a jerking motion?

What are the 13 or so dots on the right side of the graph (way after 2020)?  Data points without a year?

Yes Tor, definitely more within and between-buoy velocity variability in the CAB, though generally the velocity is slower than in some peripheral seas. You can actually follow individual buoys in scatter by following strings of dots.

Doing that is what led me to realise that IABP have discovered teleportation, because many buoys appear to teleport from the Greenland Sea to Chukchi (its clearly bugged)

Regional means per day (1979-2000):


PS, yes I think those are orphaned data points





///////// update i fixed the location bug by adding more flow control, those buoys are the ones moving out of the arctic :)

39
Arctic sea ice / Re: The 2020/2021 freezing season
« on: December 23, 2020, 11:45:30 AM »
You can find ice charts going back to the 1800's here:

http://brunnur.vedur.is/pub/trausti/Iskort/Pdf/

40
The rest / Re: The off topic off topic thread
« on: December 22, 2020, 09:54:19 PM »
There is something new on Ventusky. The airpollution, the pic is about the 2.5 particules. The ones you see in Africa, is the sand the origine of it ?

41
Arctic sea ice / Re: What the Buoys are telling
« on: December 21, 2020, 05:21:44 PM »
Getting there with this, need to add regions- suspicious of the change at 1986

42
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: December 18, 2020, 11:55:37 PM »
To get back to the Convergence question:
      The hypothesis is that the number of years remaining until the zero ice date estimated by the Extent trend will decrease relative to the date estimated by Volume as we get closer to that date.
The hypothesis says that until they meet when both Volume and Extent trends reach zero, it is the Extent date that will shift to meet the earlier Volume date, not vice versa.

      Here are the relative zero date migrations for 1979-2008 vs. 1979-2020 for each month.
The values for Extent and Volume are the number of years earlier the end date became by adding 2009-2020 to the 1979-2008 dataset.

      By subtracting the Volume shift from the Extent shift, a Positive value means that the Extent estimate moved earlier by a greater amount, which is what the hypothesis predicts.  A negative difference means the opposite, that instead of drawing closer to the Volume-based estimate, the Extent-based estimate is moving away from it. 

Jan: -2 (for Extent) minus 13 (for Volume) = -15 
    The Vol. estimate got 13 years earlier, but Extent est. became later not earlier, and thus farther away from the Vol estimate.  This is the opposite of convergence and NOT what the hypothesis predicts.

Feb:   12 minus 15 =  -3
Mar: -22 minus 15 = -37 
Apr: -45 minus 15 = -60  (Wow, Ext estimate became 45 years LATER).
May:   6 minus 19 = -19
Jun:  21 minus 20 =    1
Jul:   24 minus 15 =    9
Aug: 20 minus 11 =    9
Sep: 13 minus 14 =   -1
Oct:  30 minus 9  =   21
Nov: 27 minus 11 =  18
Dec:   4 minus 10 =  -6 

      As you noted, the winter and spring months are doing the opposite of convergence.  While summer and fall are generally showing convergence.  That makes sense in that we would expect the "thin ice" months to show convergence between Extent and Volume before the "thick ice" months.  It is when thickness reaches a critical low threshold that Extent losses increase causing it to begin to catch up to Volume.

      June being a neutral month with respect to the "Extent trend must bend down to catch Volume trend" hypothesis makes sense because it is the transition between the thick ice and the thin ice months.

      But September is a brain twister.  It seems like it should show a full expression of the 'Extent catches Volume as ice thins' trend.  My guess is that those bays in the CAA and other ice traps that are the reason for setting the BOE definition at 1M km2 of residual Extent instead of zero, are already constraining reduction in September Extent.  Those areas may be superficial thin ice that add to the Sept. Extent value without adding much to the Sept Volume because they are so thin.  As a result, the Sept. Extent value does not decline as much as it "should", but Sept. Volume does not as effectively hide the loss of ice.

      It is also a bit mysterious to see the peak "thick ice" months going the opposite direction, i.e. the Extent-trend zero date is getting farther away not closer to the Volume date.  And for March and April, the zero Extent estimate is getting absolutely later, not just getting earlier at a slower rate than the Volume date. 

      My guess is that happens because once the Arctic Ocean fills up with ice, it is full.  Even in the colder, higher ice volume past, it could not add more Extent because the Arctic Ocean is surrounded by land.   These days, the ice Extent comes from thinner low-volume ice, but that change is not reflected in the Extent value.  It still counts for Extent.  The March and April constraint on Extent in the past means that as the ice declines now, relative to the previous years, March and April don't show much if any Extent loss.  So as more years are added to the dataset, with little change in the constrained monthly Extent values for March and April, the trend towards a Zero Extent date for those months is essentially no trend at all with termination dates over 300 years from now vs. decades for the other months. 

      Actually, that point applies to ALL of the maximum ice months of January through May.  For each of them, the zero Extent year estimate is past 2300, and for Feb-May, in the late 2300s.  Thus the negative trend slope is so minor that there really isn't much trend at all due to the constraint on maximum Extent in earlier years.

      The "land bound Arctic Sea Ice" argument conveniently ignores the potential for additional Extent in the peripheral seas not bound by the coast of the Arctic Ocean.  Are your Extent and Volume data for the entire Arctic, including the peripheral seas, or are they limited to the (mostly land bound) central Arctic Ocean?

      If the data are limited to the central Arctic, then I don't have to explain away that potential for additional Extent.  But if your data also include those peripheral areas (Greenland, Okhotsk, Bering Seas) that the "land bound Arctic Ocean" argument does not address, I won't even attempt to concoct some reason to explain them away as I have already used up my daily allowance for fabricating "evidence".

43
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: December 18, 2020, 10:27:43 PM »
Dear Stephan - Nice work and much appreciated.  I think that this addition to your monthly trend posts really gets to the heart of the issue.

       Everybody else - especially Arctic amateurs like me:  Take enough time to understand what these numbers are saying.  What may appear at first glance may appear to be an innocuous table of numbers, in truth says major and disturbing things about the future of the Arctic, this planet, humanity in general, and the not-very-distant future for each us individually and the people we love.

    1) Lots of talk by IPCC and elsewhere about sea level rise by 2100.  No disagreement with that, it is a huge impactful manifestation of our insane management of the planetary life support system.  But also consider what it means to have ZERO Arctic sea ice volume in June, the month of maximum solar energy injection, by 2067.  Moreover, that the date for that catastrophic milestone gets 20 years earlier when you add 12 years to the straight-line trend to go from 1979-2008 to 1979-2020.  Will adding another 12 years, i.e. 1979-2032 put that date at 2047? 
       A planet without its reflective polar cap in June is a different planet than the one we were born on.

    2)  If 2047-2067 is too far off to get your interest, how about 2032-2035?  And what about 2026?  Is that close enough to get your attention as being real?

        ZERO Arctic Sea in August - October is also a radically different planet. While far below June, there is still considerable solar energy input in August.  And an ice-free Arctic Ocean in October (and with much reduced ice in November) venting heat into the atmosphere is bound to have strong effects on mid-latitude weather patterns. 

        The table highlights the fact that adding 12 years to the dataset used to define the trend pushes the zero volume dates 9-14 years earlier.  2032-2035 is already close at hand, but will those trend endpoints continue to get earlier as each new year is added?  Where will those endpoint dates be in just 6 more years in December 2026?  The "trend of the trends" suggests that the estimated ice-free Sept date by then could be another six years earlier, i.e. 2026.  At risk of piling extrapolations on top of each other, does that suggest that we could already have had a zero-ice September by then?

        One of the problems in conceptualizing climate change is that the perceived impacts are in the future.  People already dealing with wildfires, heat waves, droughts, hurricanes, crop failures etc. will have a more immediate perspective, but for many/most of us, the climate changes that worry us are said to be decades ahead and so bring a bit less visceral fear. 

        The dates shown for zero ice volume are nothing new to me, so I've long had the mental concern.  And perhaps I am misinterpreting and over-reacting to seeing the earlier progression of endpoint dates that result from adding 12 years to the dataset.  But my visceral fear just went up.  My emotional operating principle has been that the proverbial poop could hit the fan if global average surface temperature reaches +1.5C over preindustrial circa 2030.
 
       I keep thinking that my understanding of climate change and Arctic Sea Ice decline has reached a level of stability at which I can at least see the horror for what it is, and at least define the problem.  But the damn problem keeps growing like a cancerous tumor.  Seeing that date migration of the Sept. zero ice year has me wondering if I should recalibrate my gut-level fear threshold and "poop in the fan" date more towards August 2026 - less than 68 months from now. 

       Of course, ranting aside, the "Now" is all that we can change to affect the Future.  I hope your data serves as that one additional piece of alarming evidence that tips the scales to wake up the political and business powers to realize that the money won't do any good if there is not a livable planet on which to spend it.  Sorry for such a bleak message as we head into the traditional western holiday season.  I would highlight the fact that some good things are also underway, but this message is already long.  So yes, there are also some good possibilities emerging.  We MUST make those possibilities real.

44
Policy and solutions / Re: Oil and Gas Issues
« on: December 18, 2020, 10:13:43 PM »
For all of its other flaws the one thing capitalism does best is balance supply and demand. It can result in short term pain but whoever acts to fix the imbalance first and/or completely receives excessive profits. Nothing and I mean nothing we use fossil fuels for is irreplaceable.


For fossil fuels I think peak demand will obviously constrain markets but peak supply seams unlikely to do so before we go extinct. One way or another someone will always provide supply as long as there is demand at the right price.

45
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: December 17, 2020, 05:39:48 PM »
Glen,
I just did a "quick and dirty" experiment with a set of reduced data (1979-2008) versus 1979-2020.
I calculated the "BOE numbers" for the time period 1979-2008 and compared it with the full period (1979-2020). I reduced the evaluation on extent and volume and just performed the linear evaluation. Finally I compared the differences (column Delta) for each month (extent versus volume). If the Delta in extent is larger than the Delta in volume, the "BOE numbers" converge. If it is the other way round, the values develop apart.

Conclusions:
1. The slope of almost all months has grown steeper from 1979-2008 to 1979-2020.
2. This results in earlier "BOE numbers" for most, but not all of the months. The "BOE numbers" for extent increased in Jan, March and April!
3. There is a clear season for convergence: summer and autumn, marked in green. In winter and spring the values go even further apart, marked in pale magenta (column "Delta"). June and Sep are more or less undecided.

See attached table.

46
Consequences / Re: COVID-19
« on: December 15, 2020, 01:09:17 PM »
London & the SE sees a new mutation rapidly spreading there.....

Bit more on this:

There is no clear-cut evidence the new variant of coronavirus - which has been detected in south-east England - is able to transmit more easily, cause more serious symptoms or render the vaccine useless.

However, there are two reasons scientists are keeping a close eye on it.

The first is that levels of the variant are higher in places where cases are higher.

It is a warning sign, although it can be interpreted in two ways.

The virus could have mutated to spread more easily and is causing more infections.

But variants can also get a lucky break by infecting the right people at the right time. One explanation for the spread of the "Spanish strain" over the summer was simply people catching it on holiday and then bringing it home.

It will take experiments in the laboratory to figure out if this variant really is a better spreader than all the others.

The other issue that is raising scientific eyebrows is how the virus has mutated.

"It has a surprisingly large number of mutations, more than we would expect, and a few look interesting," Prof Nick Loman from the COVID-19 Genomics UK (COG-UK) Consortium told me.

There are two notable sets of mutation - and I apologise for their hideous names.

Both are found in the crucial spike protein, which is the key the virus uses to unlock the doorway into our body's cells in order to hijack them.

The mutation N501 (I did warn you) alters the most important part of the spike, known as the "receptor-binding domain".

This is where the spike makes first contact with the surface of our body's cells. Any changes that make it easier for the virus to get inside are likely to give it an edge.

"It looks and smells like an important adaptation," said Prof Loman.

The other mutation - a H69/V70 deletion - has emerged several times before, including famously in infected mink.

The concern was that antibodies from the blood of survivors was less effective at attacking that variant of virus.

Again, it is going to take more laboratory studies to really understand what is going on.

https://www.bbc.com/news/health-55312505

47
Arctic sea ice / Re: The 2020/2021 freezing season
« on: December 15, 2020, 11:00:30 AM »
A closer look (750m resolution) at the Chukchi ice edge. Wind blown ice drifting over warm(ish) water. Smaller floes disappearing as they cool the ocean. 1000hPa winds translating to roughly 80km surface winds forecast again for much of tomorrow.
rammb https://col.st/b7feS
stationary frames have been left in to maintain the flow of time,  72% scale to reduce to 6.3MB
further coverage to Wrangel island here


edit: surface winds were a bit lower today than forecast ~70km/h (~90km/h at 1000hPa)

Here's an update with the Bremen concentration. Starting to eat into the ESS coverage now too.


48
Arctic sea ice / Re: What the Buoys are telling
« on: December 15, 2020, 12:57:10 AM »
What some old buoys said. iabp 1979-81
edit: https://iabp.apl.uw.edu/Data_Products/BUOY_DATA/
BuoyID,Year,Hour,DOY,Lat,Lon,BP,Ts

49
Arctic sea ice / Re: The 2020/2021 freezing season
« on: December 14, 2020, 12:31:52 AM »
A closer look (750m resolution) at the Chukchi ice edge. Wind blown ice drifting over warm(ish) water. Smaller floes disappearing as they cool the ocean. 1000hPa winds translating to roughly 80km surface winds forecast again for much of tomorrow.
rammb https://col.st/b7feS
stationary frames have been left in to maintain the flow of time,  72% scale to reduce to 6.3MB
further coverage to Wrangel island here


edit: surface winds were a bit lower today than forecast ~70km/h (~90km/h at 1000hPa)

50
Arctic sea ice / Re: The 2020/2021 freezing season
« on: December 13, 2020, 08:07:28 AM »
November 22 - December 12.

2019.

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