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Messages - oren

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1
Greenland and Arctic Circle / Re: The Nares Strait thread
« on: Today at 07:04:42 PM »
I cannot imagine the arch being able to hold much longer in its current unsupported configuration. The first real stress should break it. I give it 1-2 weeks. If it lasts beyond mid-June i'd be very surprised.

2
The rest / Re: George Floyd murder and blowback
« on: Today at 07:00:01 PM »
Wili, are you okay?

3
Consequences / Re: COVID-19
« on: Today at 06:57:26 PM »
The preposterous claim that lockdown and panic cause thousands of excess deaths can be debunked easily using some critical thinking and a scientific approach. Find countries that had a severe lockdown and lots of panic, but a low rate of actual infection. If half the UK excess mortality is due to panic and lockdown, you would expect these other countries to have thousands of extra deaths due to people avoiding hospitals. If most or all UK extra deaths are due to COVID, you would expect these countries to not have thousands of extra deaths.
Israel is one such country, with a very long and severe enforced lockdown and drummed up panic by the psychopath-in-chief Netanyahu (which once and for all seems to have done something right). I do not have access to mortality data but have read in articles that even with the 284 confirmed COVID deaths, there was no excess mortality at all (or barely so), due to lower death rates from other causes during the lockdown, e.g. traffic accidents, and due to the normal death rate being much higher than 284 over the two relevant months.
So: do panic and lockdown cause thousands of excess deaths? Of course not. Truly bizarre claim.
BTW, I believe Austria is another such country, with panic and lockdown but low infection rate. Anyone has access to Austrian total mortality numbers? Someone living in Austria?

4
Paolo, I added the text from #2274 to #2249.

5
Consequences / Re: COVID-19
« on: Today at 12:19:33 AM »
In Israel a second wave could be beginning. Daily cases went from ~10-20 to ~100 within 3 days, after 3 weeks of stability. Many infections and clusters are school-related.

6
Arctic sea ice / Re: DHACSOO - A Durable Arctic Hypothesis
« on: May 30, 2020, 01:39:37 PM »
In short, WAA can melt snow, reducing its albedo and letting in the real monster, sunlight. So you cannot completely discount it no matter what calculations show regarding total energy transferred.

7
Consequences / Re: COVID-19
« on: May 30, 2020, 10:34:16 AM »
They do say it... under most likely scenario.

https://www.cdc.gov/coronavirus/2019-ncov/hcp/planning-scenarios.html

Symptomatic CFR 0.004
Asymptomatic cases:  35%

0.004 * (1-0.35) = 0.0026

The CDC estimate seems not to fit the data very well.  Not just NYC, but lots of other places.

If CFR is 2-3% in lots of places, then 10 symptomatic cases are out there for every 1 that is 'identified'.  Meanwhile positive test are down below 1 in 10 in many places.  So just where are all these 'dark' COVID positive cases hiding?
The CDC's estimate is 0.4% for symptomatic cases, so the answer does not lie in the "dark cases". Looking at the CDC's table 1, no source is listed for the CFR, except the dubious "Source: Preliminary COVID-19 estimates, CDC".
The bibliography below the two tables is very sparse, with one source for COVID epidemiological estimates and one for influenza. Weirdly, the one source for COVID is a meta-analysis that estimates CFR as 2%...
Bottom line, I find the CDC estimate to be dubious, certainly requiring a more detailed explanation.

8
Arctic sea ice / Re: DHACSOO - A Durable Arctic Hypothesis
« on: May 30, 2020, 10:17:00 AM »
On another note, you seem intent on proving that WAAs are very important to the Arctic, and that they do matter. I am not sure why you think this needs proving, it's quite obvious. The question raised by this thread is whether locations that do not often receive WAAs (away from continental landmasses) are highly likely to retain ice at minimum over the next decade, thus enticing a slow transition. To prove this, even just logically with no supporting quantification, requires more than just proving that WAAs are important.


Also, read the Slow Transition thread from start to finish, very relevant.

You took the words right out of my mouth Oren!

I have perused the Slow Transition thread. It doesn't seem like a discussion that is designed for the lay person.
And regarding that thread - many posters on this forum began their residence as lay persons, myself included. To most intents and purposes I am still a lay person, but I make it my business to learn anything I can, enhancing my own understanding and hopefully enabling some more personal contribution. Despite great difficulties in my first year on the forum, and lots of things being total gibberish to me, I recall trying to follow the discussion and even to post some useful(?) questions in that thread at the time. Make it your business to understand the detailed and difficult stuff, and your contribution to the forum will grow accordingly. Skip the hard stuff, and your contribution will be limited to lots of words with no supporting evidence.
Be aware, anyone can calculate simple formulas learned on the forum, and most anyone can use Excel or OpenOffice to make some statistics. It doesn't take a PhD, it's not difficult, but one must decide they want to invest the time and make the contribution.

9
Arctic sea ice / Re: DHACSOO - A Durable Arctic Hypothesis
« on: May 30, 2020, 10:02:49 AM »
Quote
Let's separate my suggestion into two elements. The first element is the suggestion that we should strive for proactive measures which give a better sense of what the season portends. The second element is the specific suggestion that the measure be (CAB + CAA + Beaufort).

As far as the second suggestion, I would consider it to simply be a straw man. If the best minds think ESS or Greenland Sea s/b included, I think that's a step in the right direction and would be very pleased with that 5 sea indicator of intra season progress relative to the end game.

As far as the first element, what are your thoughts there ? Do you think this is a direction to pursue? How do you feel about the 5 sea comparison which I infer that you might like better? You are the moderator here, I'm happy to defer to your judgement.
We have discussed it on the forum in the past. My position was and still is that as far as area data goes, the most relevant data is an aggregation of all the seas connected to the Inner Basin with import-export ties, plus the CAA because of its peculiar geography and ice retention. This is because the ice in these seas can move to the CAB, or be received from the CAB, thus making them one interconnected system. The same applies to energy and enthalpy in these regions. Seas that should be excluded are seas that mostly see export from the Inner Basin due to prevailing currents and winds and due to high local melt: Baffin, Barents and Greenland Sea. These seas may retain ice at minimum but that ice is not the ice that is there now, rather it's ice that will be exported to them in August or September.
Funnily enough, this is exactly the index tracked by the relentless Gerontocrat in his area updates and other updates: the High Arctic + CAA. Not because I am a moderator (irrelevant) or because that is my position, but because this has been discussed in the past and it makes sense. And because it's Gerontocrat's position of course. I track this index too in my regional PIOMAS updates, when I get around to making them. Wipneus has an Inner Basin chart that excludes the CAA. Each person that publishes statistics regularly can choose his or her own index to track, feel free to do the same. But if the stats are considered irrelevant by most of the forum, such contributions should be short and to the point and not cause too much noise and clutter. 2-3 lines of daily text and data are welcome, loads of text and repetitive analysis every day will be frowned upon. This happened in the past with some users.
Things change in August: the CAB starts crashing, and the single most important index by then is the CAB itself. But changes in the CAB will be a result of 2D developments that took place in the surrounding seas, and 3D processes in the CAB itself, all unseen in the CAB 2D data. Until August, all you see in the CAB area and extent data is noise (and the local variability of the sector near Svalbard-FJL, which should have been excluded from the CAB).
Note the best 2D index IMHO would be a pixel-level aggregation of ice concentration multiplied by the difficulty of clearing ice from that location, as measured by the statistics from the past 10 years. Thus a year that melts ice near the North Pole (such as 2016) gets more points than a year with early advances in the southern Kara. But this index is currently unavailable.

10
Arctic sea ice / Re: MOSAiC news
« on: May 30, 2020, 02:00:50 AM »
Thanks for the update. All are changes for the worse and support the loss of albedo inferred by temps and satellite images..

11
Arctic sea ice / Re: DHACSOO - A Durable Arctic Hypothesis
« on: May 29, 2020, 10:27:38 AM »
Two comments off the cuff:
* In the Chukchi and in the Svalbard-JFL line, we have not just a shallow shelf but also an incoming oceanic current which is warm and salty. These current are prevented from sinking below the cold fresh water, thus enhancing ice melt. Ignoring the effect of prevailing currents in general, and these two currents in particular, can lead one to the conclusion that shallowness is a factor in itself.
Other shallow regions do not have these currents and do not have the tendency of enhanced ice melt. Specifically, the ESS is the shallowest Arctic sea and also the most difficult to melt. OTOH, the deep Beaufort is continually fed by thick ice from the CAB during the melting season, as can be seen in the long-term animations upthread and in animations from various melt seasons. Thus its resilience is partially a mirage of ice import.
* I know you do not consider quantification an essential tenet of the hypothesis. However, once a quantification has been served by others I think it shouldn't be ignored.
"Since over 90% of the season ending ice is expected to be in the CAB, CAA and Beaufort, it would be a simple tweak to create a category for the sum of these three seas instead of the current High Arctic grouping."
I have posted data in the Melting Season thread showing that on average more ice survives in the ESS than in the Beaufort. Besides, 90% of the Beaufort and ESS ice is expected not to survive a given melt season. And what about the Greenland Sea? Thus I think your proposed "survivable ice" measure would not be quite helpful.

12
Antarctica / Re: Pine Island Glacier (PIG) Calving and Discussion
« on: May 29, 2020, 02:26:09 AM »
I'm a little surprised, but I didn't find (by searching with google) any other echo of the calving than this one  :o
Wrong search or it's like this?
Wrong search, at least judging by Steff Lhermitte. Short gif at link.
https://twitter.com/StefLhermitte/status/1265410528454811654

13
Arctic sea ice / Re: DHACSOO - A Durable Arctic Hypothesis
« on: May 28, 2020, 03:17:41 PM »
Quantifying: in the last 10 years there were two August GACs - 2012 and 2016. Both years are also lowest in NSIDC area, similar to each other and far ahead of other years.
Thus, chance of GAC is ~20%/year. Not freak. To break the area record it is probable another GAC will be needed. Ergo, chance of new area record is 10%-20% per year. Or 15%-25%, depending on your assumptions about other factors.
Note: 2012 has a huge lead in min extent, thanks to freak Sep compaction. But area is IMHO more representative of energy in the system.

14
Arctic sea ice / Re: The 2020 melting season
« on: May 28, 2020, 08:34:17 AM »
One can always hope, but I believe no serious correlation has been found between ENSO cycle and Arctic sea ice.
This can be discussed further in Does El Niño affect Arctic sea ice?

15
Lol, my bad. Kerguelen is almost double my distance...

16
I can't comment on the subject, I live about as far away from the Great Plains as possible, but I must say this was an extremely interesting eye-opening post. Well Written.

17
Nice find. BTW, if you look closely, you can see he is holding his mobile and browsing the ASIF.

18
Arctic sea ice / Re: The 2020 melting season
« on: May 27, 2020, 08:07:29 PM »
Has anyone seen the Laptev sea today on Worldview? The inner half is so dark, but it almost looks like a camera glitch because the contrast line is so straight and sharp, like that of a giant shadow. But it shows up on all the true color feeds. Is it real?
I am sure it's real. Temps not far from the Laptev have been soaring in the past few days.

19
Arctic sea ice / Re: The 2020 melting season
« on: May 27, 2020, 06:12:27 PM »
Simon, thanks for the interesting calculation. Bear in mind albedo reductions are not 40 days ahead of other years. As Phoenix said it is more reasonable to assume a week or two-week advantage averaged across the whole pack. This still would result in a whopping 15cm of added melt, which IMHO is a huge extra.

20
Arctic sea ice / Re: DHACSOO - A Durable Arctic Hypothesis
« on: May 27, 2020, 12:02:46 PM »
Thanks, well explained.
The pixel-level analysis you described is something I have wanted to do a long time ago and still want to, however I currently lack the skills and especially time to do so. I know the data is available and that it is a feasible calculation, if I have a couple of free months I know I can do it including acquiring the programming skills. Won't ever happen probably.
For each pixel, what is the probability of being ice-covered or ice-free (or % ice concentration), for each given date, looking at statistics from the last 10 years (since 2010 when the Arctic sea ice statistics seem to have stabilized a bit). Best displayed as a color-coded map of probability, animated over the days of the year.
Even better would be to compare this animated map with one containing the data of previous decades (2000-2009, 1990-1999).
A map for AMSR2 data (since 2012 or 2013), and for NSIDC data (full data available), as these have different pixels and vastly different resolutions.
Missing data would have to be interpolated from preceding and following days.
By the time I get down to actually doing it, the Arctic will probably be post-BOE...

I have made do with aggregated regional data, especially the finer AMSR2 data from Wipneus, but also the NSIDC area data. This gives some crude conclusions and insights but is mostly unsuitable to the huge and diversified CAB, in fact to any region that is made up of different ice behaviors or geographies.
Let's wait and see what this season will bring. If I have further contributions to add, I will post them here or in the "when ice free" thread.

21
Antarctica / Re: Pine Island Glacier (PIG) Calving and Discussion
« on: May 27, 2020, 11:40:46 AM »
I think the best method to show the long term acceleration is to make an animation of the whole front with a proportional timescale, for example 1 or 2 or 4 images per month, over the last 10 years or so.
If images are not available from certain times, one can double the previous image, so as to maintain the sense of time.
I have seen several such animations on Twitter (Steff Lhermite for example) but they do not cover the final acceleration this year. The best animation would be rather large, rather slow, and have a pause at the end, to enable the viewer to take in the developments. A date or year counter would be quite helpful. Animation should be fixed to grid, not to any moving point. This will enable the viewer to follow the gradual dance of forward movement and calving, the net of which is the retreat.
I am not doing this myself unfortunately due to severe lack of time (and abilities), but if anyone is able and willing it would be much appreciated.

22
Arctic sea ice / Re: The 2020 melting season
« on: May 27, 2020, 03:24:20 AM »
Rob Dekker had/has a model predicting the outcome of melt seasons using the continental snow anomaly. I always thought the model too simplistic, but there's certainly a correlation there. Whether the causation is obvious (albedo and other feedbacks) or not so much (warm weather affecting both land snow and sea ice) is another matter.
Just don't start a continental snow/WAA crusade, this can be discussed in more depth elsewhere/in your own thread if so desired.

23
Antarctica / Re: Pine Island Glacier (PIG) Calving and Discussion
« on: May 27, 2020, 03:07:25 AM »
Thank you. I have been following all the updates here in detail, but we have some readers who may be newbies or lurkers who could greatly benefit from the extra information.

24
Antarctica / Re: Pine Island Glacier (PIG) Calving and Discussion
« on: May 26, 2020, 05:50:41 PM »
Yes, thank you Paolo. I recommend adding a legend somewhere though.

25
Arctic sea ice / Re: DHACSOO - A Durable Arctic Hypothesis
« on: May 26, 2020, 04:28:39 PM »
Quote
Next question. Why does ice adjacent to Siberia begin melting earlier than ice in the CAA which is at the same latitude? Insolation s/b the same +/- some cloud anomaly. Water temp s/b < 0 before the ice begins melting. 

I see proximity to heat from land as the trigger to begin melting, preconditioning, etc. Perhaps you see it differently? 
I wish you would attempt to quantify your hypotheses.
Does the CAA start melting later than the ESS? I think not, judging by the AMSR2 area graph.
Why does the Beaufort start melting much earlier than the ESS? Same latitude, same proximity to landmasses, and deeper bathymetry.
The answer to all these questions is prevailing currents and ice movement.
Note if the CAA ice was not landfast, it would have been flushed south and melted much earlier every year. So the CAA is a really bad example.

26
Arctic sea ice / Re: DHACSOO - A Durable Arctic Hypothesis
« on: May 26, 2020, 06:57:10 AM »
Sorry, laziness, theory is a shorter word to type.

27
Arctic sea ice / Re: DHACSOO - A Durable Arctic Hypothesis
« on: May 26, 2020, 05:38:51 AM »
Another thing to bear in mind is that temperature is a problematic indicator over the Arctic. As long as there is abundant sea ice, summer surface temps will be pinned to the ice melting point, while the ice might get thinner and thinner. Besides, the Arctic can get a lot of its melting energy directly from the 24-hour sun, with albedo and cloudiness playing an important mediating role in this process.

28
Arctic sea ice / Re: DHACSOO - A Durable Arctic Hypothesis
« on: May 26, 2020, 05:32:32 AM »
I have seen similar animations of sea ice export over past decades before I found my way to ASIF and acknowledge that ice export is a significant alternative means of transport. Instead of bringing heat to the ice, export transports ice to the heat. I certainly wouldn't rule out the possibility of massive export events leading to eventual BOE.
The point of these videos was not to highlight export but to show the prevailing movement of ice from Siberia towards the CAA, thus explaining why the remaining ice ends up bunched against Greenland, Ellesmere and the CAA in September, with no need for the DHACSOO mechanism of distance from heat advecting continents and shallow open ocean as an explanation. A mechanism which I believe is not a good explanation and will not protect the ice from further warming and more mobility.

Quote
In terms of attempting to prove whether the hypothesis is accurate, I don't have a vision of a classical research paradigm where i'm a principal investigator doing all the work and then presenting my findings for someone else to read.

I'm thinking more in terms of a classroom setting where everyone puts themselves in the role of investigator and putting out an idea for them to consider as we all watch the experiment unfold together.
This could happen if more people felt DHACSOO is a viable explanation and predictor. I am not sure that is the case. If you can't put in the time to quantify your own theory, I expect others, with less conviction than you, will not invest much effort either.
My own initial reaction was skeptical and I've given some reasons (back when this was presented in the "when ice free" thread). Now I see no reason to spend time and effort investigating a theory I haven't seen proof of and am not convinced of its viability.
For example, I believe the location of remaining ice at minimum is not exactly as described in the initial post of this thread, and that deep/shallow plays much less of role than other factors. However, were I to be shown convincing quantified proof of this, I might be more inclined to investigate further.

Quote
I suppose the hypothesis has two separate elements. One element pertains to the outcome (slower rate of progression than the previous linear assumption) and the other relates to the root cause (distance from NA / Asia and non-linear bathymetry). The outcome has the potential to smash the entire hypothesis if the ice moves much further into the Arctic this decade.

If the coming years do not show much further progression of ice loss, then we can be right about the outcome and still wrong about the root cause. In that case, it would be important to evaluate alternative hypotheses which propose to demonstrate that other factors are more important than distance from land based WAA and the transition to deep bathymetry.

I hope others will take these ideas as an invitation to offer their own ideas as to why the melting stops where it does at seasons end. It's an interesting topic.

I care more about the outcome than the root cause. If the ice holds up longer significantly longer than people think based upon completely different factors, I will be very happy. During the interim between now and when the future reveals itself, I'll suggest that there may be merit in promoting possibilities that give people reason to hope that sea ice disaster will be averted. The presence or absence of hope could potentially be a factor in the outcome.
Others have indeed, already, offered their own ideas as to why the melting stops where it does, and why a collapse to BOE is not imminent. But the root cause - and not the end result - is the interesting part. Otherwise we just wait until one year the end result is different. OTOH, a good root cause can be used for prediction, and can be checked against unfolding events.
For example, Chris Reynolds predicted winter volume in the Inner Basin to stabilize, once the long-term process of MYI replacement by FYI is finished, due to freezing season length being stable, FDDs decreasing only slowly, and the low marginal effect of added FDDs on FYI thickening. And with winter volume stable, summer declines should take place much more slowly than expected at the time. A much more convincing and quantified theory than DHACSOO, though with its own weaknesses, exposed during the winter of 2016/17 when freezing was much delayed and Inner Basin volume fell to a new low.
I fear your theory will not see much traction and discussion without a strong initial quantification of its merit.

29
Arctic sea ice / Re: DHACSOO - A Durable Arctic Hypothesis
« on: May 25, 2020, 11:47:52 PM »
Some advice:
As background, take a few minutes to study the dynamic behavior of past melting seasons and movements of multi-year ice.





To corroborate the working theory, find a way to quantify where indeed is ice more likely to survive at the annual minimum. This can be done by gridded computing, by animation, by picking certain locations and manually counting the years (e.g. since 2007) in which they were ice covered, or even by using crude regional area and volume statistics . But not quantifying this at all makes the hypothesis into an assumption.

Also, read the Slow Transition thread from start to finish, very relevant. When Chris Reynolds came up with that theory he quantified a lot of its underlying assumptions and postulations. You can also read the posts on his old blog, DosBat.

30
Arctic sea ice / Re: The 2020 melting season
« on: May 25, 2020, 09:25:35 PM »
Oren , you were alluding to the RATE of sea ice area decline. Would this be absolute or % decline ?
I think absolute decline is more important and is a measure of the energy input into the CAB
Not sure what post you are referring to, but I agree absolute area decline is the more important measure.

31
Arctic sea ice / Re: The 2020 melting season
« on: May 25, 2020, 07:50:43 PM »
2020 vs. 2019
Surprisingly, the CAA looks much worse in 2020. (Hopefully these are just artifacts).

32
Consequences / Re: World of 2030
« on: May 25, 2020, 12:27:51 PM »
Quote
Windmills continue to increase power
Wind turbines, not windmills.

33
Consequences / Re: Places becoming less livable
« on: May 25, 2020, 07:37:29 AM »
There is at least one "population" thread (possibly two or more) where this better belongs. I recommend to move it there.
I should note that it seems widespread agriculture in Africa did not begin with European colonization, but much earlier.
Some relevant info is found here:
https://en.wikipedia.org/wiki/Economic_history_of_Africa
In addition, are you sure about this European-induced shift from communal tribes to single-family units?

34
Arctic sea ice / Re: The 2020 melting season
« on: May 25, 2020, 06:57:16 AM »
Temperature reached +10.1°С in Sterlegov (75.41 N 88.90 E). Previous record of May was +6.8°С in 2011.
Average daily temps normally cross zero in this location in mid-June. This year it happened one whole month early, and is sticking around.
Other locations around the Kara Sea (noted on map) are also abnormally warm.

35
Arctic sea ice / Re: The 2020 melting season
« on: May 25, 2020, 06:20:12 AM »
A better approach would be to limit the amount of posts hashing the same postulation. This is not the first time somebody came up with the idea that the rate of loss will be slower, and you are not a lone voice in thinking that, rather you are a lone voice in voicing it so much.
Wait for new data, or find old data and present it originally. In the meantime, don't try to respond to any and every post that differs from your opinion. If you must respond, do so in one such post per day. If you prefer to post endlessly on your favorite subject, feel free to open a new thread where it will not disrupt.
Using the quoted example, S. Pansa came up with an interesting fact relevant to the thread's subject - Slater's model's prediction is nosediving. The late Slater's model is well known hereabouts and did not need much explanation. Whether its prediction is good, bad, wrong or right doesn't matter. Your response, OTOH, did not provide any new information. Do I think the model is the holy grail? No, the opposite. Did I respond? No, I did not have anything new or interesting to contribute on the subject.
If you believe most people here come for the drama and are ice doomers, you believe wrongly. Most readers of this thread come here with an open mind, have no preconceived notion of what is going to happen, If they have one they change it monthly, and are humble enough to realize the Arctic is greater than them and is always full of surprises.
Maybe you have not read Friv for enough years to realize he is the first to throw a wet blanket on people's new record expectations, as soon as the evidence points in that direction. His personal wishes and love of drama notwithstanding, science is the judge.
From what I have seen so far, it seems you have built a preconceived notion of how the season will end, and constantly look for various reasons to support this conclusion. You are not being reprimanded because of your claims or opinions, but because of the way the discussion is being held. Take a breath, stick to the science, follow up on your claims and items of interest from time to time, bring new perspectives, and keep an open mind.
If you think current Beaufort volume or extent or whatever predicts Beaufort extent at season's end, why not analyze this quantitatively using past data?
If you think extent correlates with continental temperatures, why not quantify past temperature data of various weather stations, correlate with CAA and Beaufort ice, and compare to the current year so far?
I hope I have made this clear enough. You are a prolific poster with a good scientific approach, which is why I took the time to write such a lengthy post of explanation. But you must make some changes, as outlined herein.

36
Arctic sea ice / Re: River ice and Discharge
« on: May 25, 2020, 04:09:03 AM »
Some Lena information. Water level in Kusur, about 200km upstream of the Arctic Ocean, have risen sharply in the last few days. I do not have data to compare it with other years. As can be seen, serious discharge usually starts in June.




One of our Russian-reading users could perhaps crack this website to find if there is more information on current discharge and temperatures, and comparison with other years.
http://gis.vodinfo.ru/

37
I hope you revisit these snow predictions in June and in August. I'll reserve my doubts until then.

38
Arctic sea ice / Re: The 2020 melting season
« on: May 24, 2020, 11:18:47 PM »

Slater's model has picked up the current preconditioning  and thinks it is favourable for strong melting way into July.

It predicts 7.34 m km² for July 13th, currently nosediving ...

LOL. The ice apocalypse is a cottage industry. I'll take the over.  8)

PS - There's a dedicated thread for Slater and another dedicated 2020 prediction thread.
Phoenix, I will not tolerate more such posts with no content and inflaming language that stirs up this thread for no good reason..

39
Greenland and Arctic Circle / Re: The Nares Strait thread
« on: May 24, 2020, 07:52:12 PM »
This loss of important structural support could result in a very early breakup of the arch.

40
Arctic sea ice / Re: The 2020 melting season
« on: May 24, 2020, 05:48:06 PM »
Average AMSR2 area contribution in mid-Sep (sorted, unrounded, km2):
CAB: 3,300,562 (max 3,606,190)
Some people might get confused  because
- the CAB area in the NSIDC analysis is 3.224 million km2,
- the area of the CAB used by Wipneus is larger (the surrounding seas smaller).

And this is where I get confused - I thought the CAB area used by Wipneus was around 3.45 million km2, not the 3.60 million you quote. Do you think you could post the sea areas as used by Wipneus. I think you've done it before (or someone else has).

ps: The Barents, Kara Seas & CAA boundaries are the same, it is the Laptev, ESS, Chukhi & Beaufort Sea areas are lower in the Wipneus analysis, as NSIDC (Stroeve et al) moved the boundaries north by a series of straight lines along 80 North.
The max I gave in the above post was max area in mid-Sep, not total area of the sea, as determined by max over the whole AMSR2 record (in km2). Note the Wipneus map, previously used by Chris Reynolds, was taken from the now-defunct Cryosphere Today (CT) website.

CAB: 4,432,026
Chukchi:  606,637
Beaufort:  529,475
ESS:  934,240
Laptev:  736,842
Kara:  885,647
CAA:  769,964

41
Arctic sea ice / Re: The 2020 melting season
« on: May 24, 2020, 04:52:14 PM »
Extent is the most widely watched measure. Simply put, low compaction (area/extent ratio) signals a high risk of upcoming extent losses.
For a given amount of area, indeed lower compaction means the ice is more vulnerable.

42
Arctic sea ice / Re: 2020 Melting Season Predictions
« on: May 24, 2020, 03:24:13 PM »
Done, sorry hadn't noticed this until Niall pointed it out.

43
Arctic sea ice / Re: The 2020 melting season
« on: May 24, 2020, 03:21:58 PM »
Quote
So, 2012 is one good "hindsight" about how much melt work a season can do. 
Indeed F. Tnioli, and very well explained, good post.

To your point Phoenix, yes it's true that early losses in peripheral seas such as Okhotsk, Hudson and Baffin are less meaningful than the same losses in the Inner Basin.

44
Arctic sea ice / Re: Nullschool Forecasts
« on: May 24, 2020, 02:42:58 PM »
I sympathize Glen. I've learned over the years to recognize some of the hinted phenomena, but I still often find myself cluelessly scratching my head while someone goes gaga about a forecast.

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Arctic sea ice / Re: 2020 Melting Season Predictions
« on: May 24, 2020, 12:38:13 PM »
P.A, do you want the poll to be removed, or activated?

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Arctic sea ice / Re: The 2020 melting season
« on: May 24, 2020, 09:20:50 AM »
Average AMSR2 area contribution in mid-Sep (sorted, unrounded, km2):
CAB: 3,300,562 (max 3,606,190)
CAA: 169,524 (max 244,075)
Greenland Sea: 100,082 (max 179,770)
ESS: 65,956 (max 227,358)
Beaufort: 61,956 (max 189,835)
Laptev: 31,930 (max 112,984)
Baffin: 16,394 (max 31,070)
Barents: 7,976 (max 59,347)
Kara: 6,513 (max 28,714)
Chukchi: 3,619 (max 13,253)

Beaufort is indeed a variable sea, thus important to deciding the minimum, but the ESS is more variable, and the Laptev is also a respectable region of interest. In addition, the actual date of the minimum matters a lot and can vary by 2 weeks.

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Arctic sea ice / Re: The 2020 melting season
« on: May 24, 2020, 08:29:08 AM »
the areas of the Arctic likely to retain ice at the minimum (CAB, CAA and Beaufort).
Get your numbers straight. The areas most likely to retain ice at minimum are the CAB, the CAA and the Greenland Sea. Of the 8 years in the AMSR2 record, 5 had near-zero ice area in the Beaufort in early Sept, the rest had 150k-200k. The ESS had 3 years with 150k-250k, 3 years with 50k, and only 2 at near-zero. The Laptev is also sometimes a contributor, and even the Kara and Barents with some small amounts.
Later I will calculate average contributions to the Sept area minimum, of course you can do that yourself by downloading the file from Wipneus.


https://sites.google.com/site/arctischepinguin/home/amsr2/data/UH_AMSR2_3.125km_Area_Extent-v0.0.txt?attredirects=0&d=1

Moderator Note: everybody understands your theory by now, you don't need to post so many posts defending it, unless new data comes up.

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Arctic sea ice / Re: "Stupid" Questions :o
« on: May 24, 2020, 08:12:54 AM »
A more detailed response to the "June elbow", using the regional NSIDC extent graphs:
* Okhotsk and Bering mostly melt in April and early May.
* Kara and Laptev only start melting in June, the same applies to the Beaufort and Chukchi.
* The landlocked and huge Hudson (forgotten in my earlier response) also starts melting only in June, but then has extensive and predictable losses.
* The only seas losing extent linearly during May are Barents, Greenland and Baffin.

Thus when the main engines die out but the other haven't begun we get the May slowdown, in turn causing the June "elbow".
I get the feeling that if Hudson Bay was taken out of the stats, that elbow could disappear.

49
Arctic sea ice / Re: "Stupid" Questions :o
« on: May 24, 2020, 08:03:44 AM »

50
Thanks for the weather updates and analysis. Just please don't start with that old theory. "Early growth in snowpack by August as most of the rest of the Arctic becomes completely overwhelmed in heat" will not happen.

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