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Messages - F.Tnioli

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101
Arctic sea ice / Re: The 2019 melting season
« on: July 26, 2019, 11:40:45 PM »
...
All that said - we do get consistent and timely measures with equally consistent comparison values for decades of history - we can get wrapped up on daily data variations, but the bigger picture of year over year and decade by decade change is valuable and with all it's limitations seems to be a valid measure of what is happening.
Good discussion. But this particular point, i can't agree with. Decades of history means nothing if you have the system changing its mechanics - not just amounts of this and that. And Arctic does exactly that, especially this melt season, because of earlier and much larger areas of open water during this melt season - if we compare to "decades of history". See, those areas absorb lots of heat which historically was spent to melt ice in those areas - but this season there was no ice to melt then and there, and so that heat warmed up water column instead. And much of it ends up bottom melting more ice - just some place else and quite much later during melt season.

I am convinced amount of this action is both very significant for this melt season, and quite unprecedented anyhow "historically". This year's pacific side was so open so early, etc... We still do not see full extent of all the absorbed heat during last ~50 days, but we certainly see some of it in action now. And bottom melt is exactly the sort least noticeable from above, until things start to fall apart - which then looks very much like that picture jdallen posted, i believe.

Further, warmer water column alters not only ice melting later-on, perhaps even more importantly - it alters weather systems around, thermal gradients near remaining ice, slows or halts any otherwise possible re-freeze processes. You know how land areas around the globe which are near large bodies of water have their local climate "moderated" by such a big water body? Year-round. Well i see no reason for similar effects to not happen in Arctic, and they gotta increase as open water areas appear larger and earlier.

This all exactly invalidates estimates of current situation based on historical measurements. How much it does? How big is the error for every particular date / region / measurement kind? Obviously, hard to tell. But i prefer to err on the safe side of things and limit usage of "historical comparisons", when there are reasons enough to be unsure what are the answers to those questions.

Especially since even largest bodies already made that same mistake, and quite many times. Like IPCC predictions of summer Arctic ice holding up to some 2080s or so, which were official and all-serious not much more than just a decade ago - were much based on "historical comparisons" indeed. I guess you know how different is what was observed and the line IPCC had in that prediction for up to current time? More than humiliating - i'd say, shameful.

So you see, can't quite rely on history anymore. Too fast a change is happening there. The ice desert of Arctic is not quite there anymore...

102
Arctic sea ice / Re: The 2019 melting season
« on: July 26, 2019, 08:48:11 PM »
I already mentined above, jdallen - it much depends on who's parsing the data. There are always some "agreements" as to what actually counts as "water" and what counts as "ice" for area calculations, and tresholds vary from institution to institution. DMI, iirc, is known to often have relatively stricter tresholds for example - means they'll see less of that photo of yours as "sea ice" and more as "water" than most other institutes-and-such out there. Varying grid sizes... Etc.

103
Arctic sea ice / Re: The 2019 melting season
« on: July 26, 2019, 08:24:54 PM »
...
So my major doubts are with the US Navy's HYCOM gifs.
...
Jokes aside, sure, doubt is for every model, some more, some less. But there is one thing unique about US Navy's Arctic Ice matherials - which is, those guys actually go there all the time. They can and certainly do verify their model's results with actual measurements. This among other things is also military matter: certain subs have certain limits about how thick ice they can push through, and thus it's important to know where both sides' subs can possibly appear and fire away.

104
Arctic sea ice / Re: The 2019 melting season
« on: July 26, 2019, 08:12:18 PM »
HYCOM - Arctic ice thickness (CICE) model - July 26 - August 2

<GIF of shitty model here>


If you're looking at that for an estimate of the pack edge retreat, I give you a pass. If you're looking at the thickness and believing, as somebody pointed out, that the thickness at the NP is similar to the thickness at ESS, we are in serious trouble.
"Shitty model" you say. Science.gov website says quite another thing, on this page. Guess who we tend to believe more: your word, or said page?

This ain't to say we diss you. This is to say we diss your post for the lack of substance. And we'll keep doing so unless you bring unbiased and verifyable arguments to the table. Days when people in this sort of debate had the luxury of trusting ones' fair word - are long gone, sadly.

105
Arctic sea ice / Re: The 2019 melting season
« on: July 26, 2019, 08:00:55 PM »
I'm not sure what the best thread for this bit of new information is, as it is a general analysis of melt, but there is a brand new article out in the journal Science, released today that bodes ill for the ice in the arctic and Antarctica. 

"Direct observations of submarine melt and subsurface geometry at a tidewater glacier

    D. A. Sutherland1,*, R. H. Jackson2,†, C. Kienholz3, J. M. Amundson3, W. P. Dryer3, D. Duncan4, E. F. Eidam5, R. J. Motyka3,6, J. D. Nash2
...
I am sure it's very welcome to present the article in this thread exactly like you did, as it may be useful bit of extra understanding of this and other melt seasons for quite many people here. In the same time i am also sure that discussing details of such a paper in this topic - would not be right. So ideally such pieces are to be posted with a link to another topic where anybody who's interested to further discuss it - could do so. For example, this and this threads, while less active, - are to stay active for years, and contain quite a few arguments this new paper could change, sometimes dramatically.

106
Arctic sea ice / Re: The 2019 melting season
« on: July 26, 2019, 07:45:54 PM »
...
*** In a few Old Peoples' Homes, arguments are encouraged. It seems it is good therapy instead of being drugged up in an over-heated room watching DayTime TV.. (I am prepping for old age so research is a part of the process.)
No worries - most of us have an OK sense of humor here. And it sure helps to be prepping for your later days however possible, yep. To this end, here's one super-short tutorial about one particular method of argument. Hope this knowledge will help you, if just a bit, in the future. :P

107
Arctic sea ice / Re: The 2019 melting season
« on: July 26, 2019, 02:49:56 PM »
Likely that both are.
Well i wouldn't say "likely" (also, no scorning, remember? :) ) , - but "possible" both are, yes. Which is why i used "at least" in the post you quoted, you see.

But which way? I mean, if you say it's not 2m+ CAB average and not ~1.2...1.4m CAB average, then what is your idea? Somewhere in-between, or <1m? Intresting!

108
Arctic sea ice / Re: The 2019 melting season
« on: July 26, 2019, 02:37:49 PM »
Guys,guys!

We know why Neven is away and you want him to come back to this???

Take a chill pill, kiss and make up .and lets move on please?
Yep, i concur with Gray-Wolf 100%. Everyone just calm down for Neven's sake, please!

P.S. If someone missed what it's about - it's extraordinary circumstances currently, for Neven: he's enduring through much stressful, very obligating and major family matter, at this time. This is what keeps him away and very busy, for now. Lots on his shoulders now, as it is - and we can help by at very least staying civilized in the forum here.

109
Arctic sea ice / Re: The 2019 melting season
« on: July 26, 2019, 02:30:07 PM »
... Usually what happens now is that scorn is placed upon the data for being awkward.
...
Now who would be the brave soul to claim that on this one, "blue" and "purple / pinkish" colors all mean 2m+ thickness? Rich, wanna volunteer? I love a good laugh. :D
Not sure I believe that figure  ???, its almost implying the rotten ice in southern Hudson has the same thickness as 50% of the CAB ice
Nope, Simon, you can't say that! See, per implied gentlemen's agreement with gerontocrat, we do NOT place any scorn on data for being awkward, this time!

I mean, if he wishes no scorn to be put on data he presented, then none should be placed on data that contradicts his data, too. Means, we just gotta sit and stare and meditate on two sets of data at least one of which is clearly wrong. I don't mind, myself. Meditation is useful! :)

110
Arctic sea ice / Re: The 2019 melting season
« on: July 26, 2019, 11:40:29 AM »
... Usually what happens now is that scorn is placed upon the data for being awkward.
Well, let's do something else for a change then, eh? From very previous page of this topic, here's what tells much different story (unless, of course, you'd be color-blind):



Now who would be the brave soul to claim that on this one, "blue" and "purple / pinkish" colors all mean 2m+ thickness? Rich, wanna volunteer? I love a good laugh. :D

111
Arctic sea ice / Re: The 2019 melting season
« on: July 26, 2019, 01:35:22 AM »
Repeating myself, the continuation of the current wave, days 6 to 10 can be evaluated using 5-day average over ensemble of forecast, to fail in the conservative side.
What the EC ensembles say is that the Greenland ridge will be strengthened, and the corresponding high will be strongly reinforced. Not as bad circulation as present, but not party time for the pack either. And a very bad news for Greenland
Hot damn! HOT DAMN! Friv, where are you? We need your writer's talents, sir. Seems this one is quite a fitting occasion...

This is not just "very bad". This may well be total melt of Greenland surface of unprecedented proportions - as well as similar kind of event for sea ice north from Greenland. Hell...

See, 11...12th June, this year, nearly half of Greenland already melted. This means less snow cover and easier-to-melt layers of refrozen snow/ice mix (those always have less reflectivity than proper snow - so lower albedo). Back in those days in June, Greenland was losing ~12 billion tons of ice/snow per _day_.

Sure it was a bit higher insolation than now, but then whole thing was colder on average, i bet.

But most importantly, that june melt event was done by a high some ~1025 hPa strong (seeing it here). But this one we see developing, i see quite a few days being in 1030s, and i even see 1040+ couple times in the forecast! Wow. And yep it seems extremely stable system, too.

Snow thickness is projected to steadily decline next ~5 days from what i see, across whole Greenland, including every last grid cell in its central regions. Most of central Greenland i see its snow cover going from 48...72 cm to just 24...36 by August 1st, i.e. losing ~half of its snow cover despite all the elevation central Greenland has, - and the high seems not to be going anyware past that date, too. You don't lose those amounts of snow without massive melt event going, me thinks...

I suspect that much of ice retreat we now see directly north from Greenland is powered by melt water bottom melt, already. That water just gets significantly warm while running off the land, and then bottom-melts lots of ice once it's in the ocean. But after this event unfolding, with possibly over a hundred Gt meltwater runoff in a few days (i bet under-ice water bodies of Greenland are already overflowing by now), means up to few dozens Gt meltwater in a few days to the North side of it, and with such an insolation and already warmed up coasts? Can't even remotely evaluate the consequences, other than suspecting they might be devastating like nothing else before in the region.

Next week might well be no less historical than the GAC of 2012, gentlemen.

112
Arctic sea ice / Re: The 2019 melting season
« on: July 26, 2019, 12:11:06 AM »
It takes a 80m high column of water at 4-5deg C to melt a single meter of ice. Melting of ice takes so much energy that it just takes a lot of time. The temperature of sea surface is some factor, but IMHO is not that important.
1st, this is factually wrong: 333.55 kJ to melt one kg of ice, -4.2 kJ to cool 1 kg of water by 1C. Cooling down 80 kg water by 4.5C would release 4.5 x 4.2 x 80 = 1512 kJ, i.e. ~5 times more than needed to melt 1 kg of ice. Means, it's not 80m high column per your example - but only ~16m.

2nd, both me and Oren already asked to stop doing napkin physics in this topic, recently. This topic is for melting season dynamics with only limited and small deviations. Normally you'd be asked to proceed with any more such posts in a more appopriate thread, like science base threads about ice melt physics, which this forum also has - but if you'd keep doing such mistakes, then with all respect and entirely friendly intent, i'd advice to not make them. See, you can mislead others with such posts. It's bad. But for sure it never hurts to ask and to post assumptions asking others to verify - in said ice physics threads. Please, do.

3rd, SSTs are not any much important any well inside ice-covered regions, as long as ice concentration is well above 50% (all the ice keeps SSTs near 0C); but at the edges of any ice cover and in areas with ~50% or lower concentration, especially with large subareas of open water (10+ km2) under clear sky and/or with wind blowing towards sea ice - SSTs become very important, in terms of melt season progress. Water currents also a factor, SSTs in stormy areas vs weak / thin ice cover is a dramatic thing, etc. I.e. SSTs importance is highly variable thing for a melt season and can't be estimated without taking other things into good consideration. Experienced posters often omit those details, only discussing SSTs when they are indeed affecting ice melt much, and simply not paying attention to SSTs when their consequences can't be anyhow foreseen in a definitive way. Which does not mean those guys don't make said consideration, you see. They do.

113
Arctic sea ice / Re: The 2019 melting season
« on: July 25, 2019, 05:44:41 PM »
HYCOM - Arctic ice thickness (CICE) model - July 25 - August 1

RIP Ice :'(


RIP it is. If this is any correct, i'd say we'll have multi-hundred drops early august in the bottom-left quarter alone. So much white there, and i've seen, just couple hours ago, some forecasts of much clear sky in that same quadrant for next 3 days.

114
Arctic sea ice / Re: The 2019 melting season
« on: July 25, 2019, 04:30:37 PM »
...
So what evidence would you look for to prove that a massive heat influx is actually taking place?

The simple answer seems to be that we should see a rapid increase in area loss, reflecting the onset of surface melt.
For area to start dropping, there must be openings larger than grid size for any given method of observation - open water areas or areas with significantly below-100% ice concentration which are dozens or hundreds square kilometers which are counted as "not sea ice", if we talk satellite sensors. Often strong melt happens without such openings forming, which is why massive melt may be taking place even while an area is "officially" remaining 100% area. Much depends on data parsing methods used by each particular research body, which actually differ quite much, too.

High air pressure areas is a major hint, traditionally used by many as a good indication during a melt season. Cloud cover direct observation (by satellites) showing areas without any cloud cover to talk about for significant lengths of time - is proof enough (as long as Sun pushes out high insolation during the season). That's if we just talk sunlight, of course. Bottom melt, rain, air heat waves, GAC-like events all have their own kinds of heat influxes and their own ways to be detected (which are not always possible to do).

115
Arctic sea ice / Re: The 2019 melting season
« on: July 25, 2019, 07:51:54 AM »
...
I'm skeptical that any of them are important ...
I just sent you a PM with a link which should easily remove this scepticism of yours, as well as with further info on your other points. Like i said before, i believe it's best we move this dig into further physical principles and basics away from this topic.

116
Arctic sea ice / Re: The 2019 melting season
« on: July 25, 2019, 07:14:55 AM »
Slow Wing, here's a simple line from this page, which is about actual measurements of insolation at Barrow (which is quite far from the Pole, but still should be good enough to solve your doubts about how much reaches the surface):

"... maximum daily incident solar radiation (330-360 W m-2) at the surface".

P.S. And just to be safe, note that monthly mean insolation for July at Barrow, given on the same page - is appropriately low 120-130 W/m2 at the surface, as it includes all the cloudy days, which for July at Barrow is ~75% days of the month (source). This also well demonstrates how dramatic is the difference between clear skies and clouds in terms of insolation.

117
Arctic sea ice / Re: The 2019 melting season
« on: July 25, 2019, 06:22:14 AM »
Rich, i am not going to answer your questions since you did not answer mine, above. Instead, would you kindly read the last line of this recent post of yours, aloud, to yourself, a few times? Perhaps this will reveal what's going on here, to you. ;)

Been some good fun, feel free to drop another bucket of bolts in response, but i'm not game anymore, as long as you keep at what you're doing last couple pages. Cheers.

118
Arctic sea ice / Re: The 2019 melting season
« on: July 25, 2019, 05:16:59 AM »
...
If someone wants to know where I get my "crazy notions".... they come from this melting season. ...
Huh? Is there "this melting season" weed on the market these days, and you're smoking it? Because that's the only way the statement can be believable, to me (and quite few others i bet).

Jokes aside, Rich, you either can't or don't want to do non-biased discussion here, it seems. Whichever the case, in my experience such manner of posting will not be tolerated by this forum's administration forever, especially not in this topic. Just personal opinion of mine though.

Take care.

119
Arctic sea ice / Re: The 2019 melting season
« on: July 25, 2019, 02:45:15 AM »

SSTs in the ice pack are buffered at 0°C or thereabouts by melting ice. You don't see the SST increase until all the ice is melted. You can't tell how much ice is melting by looking at SSTs until all the ice is gone.

So, I went back and checked the thread to see if anyone posted an image of 2M temps this year in the ESS while it was still covered in ice.

Check post #2368. It's showing 4-5C 2M temps over the ESS while it was still covered in ice. Please explain how that was possible.
You've been told about SST and you're checking 2M temps. Do you know "SST" means "sea surface temperature"? Are you aware 2M is 2 meters above said sea surface? Do you know how much length 2 meters is? And do you realize that sea surface is ice/water, while 2M above it - is only air? Do you know that given air thermal conductivity, the idea of 4-5C air 2 meters above ~0C ice/water is nothing unusual?

I'm just curious where exactly that joint made you slip, you see. Peace. ;)

120
Arctic sea ice / Re: The 2019 melting season
« on: July 25, 2019, 01:30:34 AM »
The dipole has arrived. But it does not come with a lot of heat.

The SST's are very warm around the edges, but in no rush to invade the CAB.

2019 leads in some categories, but area losses are skipping, suggesting lost momentum.

The wind remains impressive, but mostly cold and pointed away from Fram. Some compaction, some dispersion, some export. Nothing record breaking.

The ice is in crap condition, but it won't disappear w/o good reason. Especially from the CAB.
 
I'm rooting for a record and anything else that might occur in the short term that will jolt the world ioward the necessary urgent response to AGW.

Second place doesn't make headlines. That where it looks like we're headed.

What are you smoking? The impending heights and 850 temps are all-time highs as projected by EURO. I also think that the tempering of area losses is due to cloud interference but this is more conjecture on my part. We shall see.
Now this is one interesting question for sure, bbr - what is he smoking? Well, based on such a peaceful part of his post - "Some compaction, some dispersion, some export. Nothing record breaking" - i dare suspect it's labrador joint. It makes one really peaceful, see? :D

121
Arctic sea ice / Re: The 2019 melting season
« on: July 25, 2019, 01:18:05 AM »
I saw couple signs that say that you're absolutely correct about the CAA part, lately. And very true about extent and area, too. Apart from (often difficult, uncertain, or not available) measurements of current ice volume / thickness, i'd say small dips in concentration % could sometimes be one useful hint about such processes. I wonder if you use that as one of quick things to check, yourself.

Well, hints like that help, certainly. One of the challenges, of course, is determining how to section off areas for analysis. That's why I tend to focus on just the Sverdrup Islands, rather than wider areas like the Queen Elizabeth Islands or the whole of the CAA.

Even a small change in one of the satellite-discernible metrics (area, concentration, extent) for the Sverdrups alone is likely to be significant. But changes of similar magnitude for the whole of the CAA are potentially just noise. For example, the CAA's conventional boundaries include the North Water Polynya, at least in part. The CAA also includes smaller areas of continuously (or nearly so) open water, including at the west end of James Sound (at North Kent Island) and in the general vicinity of Bailie-Hamilton Island. Even absent significant regional melt or fragmentation, the exact boundaries of these open water phenomena can easily swamp the signal of more concerning events when considering the region broadly.
Definitely just noise for the whole of CAA, yes. Indeed i meant small dips in concentration detectable for a single "mechanically" region - i.e. an area which has all the ice in it moving in practically same direction (if any), affected by one and same water current under it (if any), and practically same wind direction, speed, precipitation kind/amount above it (if any). And i meant eye-balling it (sats photos) much more than using any processed concentration data, too.

P.S. Pleasure to read your posts. You definitely know what you're doing. I wish you good luck with your further work, sir.

122
Arctic sea ice / Re: The 2019 melting season
« on: July 25, 2019, 12:47:51 AM »
i'd say we can safely settle on very approximate range of ~180...300 W/m2 absorbed at the surface under clear skies (high pressure systems) for late July / early August
So about 5-9 cm of ice per day might be melting under the clear skies of the big high pressure system soon to arrive in the CAB.

Reason: it takes about 35 W/m^2 to melt each centimeter of ice per day:

Energy flux to melt 1 cm thickness of ice per day [in units of W/m^2] = 1 cm x (10^4 cm^2/m^2) x (334 J/g latent heat of melt) x (0.9 g/cm^3 density) / ( 3600x24 seconds/day)
= 35 W/m^2
(Uses the definition W = J/s)

DISCUSSION POINT
Doesn't that seem a bit high?
...
Understandable confusion. What you miss in the basic picture of the process - is basics about how absorption works. You assume that all 180...300 W/m2 goes into melting the ice. In reality it does not: like already mentioned above, some of that energy is lost via evaporation (mostly from liquid water at the surface, but even dry ice actually evaporates slowly).

Further, whenever there is any noticeable open water - most of those 180...300 W/m2 gets absorbed at significant depth of downwards water column, since you know, water is a transparent thing. Noticeable amounts of light are present even at ~200 meters depth if my memory serves, - that's basically how deep significant fraction of absorption happens.

Same effect also happens to a lesser degree through the ice itself whenever there is no snow cover on it, increasingly so when the ice getting thinner: much sunlight simply goes through it and into water column below it, since ice is often significantly transparent, itself.

With water density being the highest at +4 Celcius iirc, a layer of colder melt water often remains near remaining ice, with warmer water sinking down as it's a bit heavier (though this much depends on water column mixing factors present at the location), which is another "sink" for some absorbed heat. "Sink" if we talk immediate insolation effects on ice thickness, of course - but in the same time, often it's also "delayed bottom melt" if we look further into melt season, as quite often large masses of warmer water from below end up getting near the surface and doing said bottom melt to still-remaining ice at a later date. This effect gets really nasty whenever some layers of water end up much warmer then 4C, thus losing density and starting to go up "themselves", without any water current forcing.

Yet one more heat sink which "steals" much of absorbed energy - is IR re-radiation. We know that in the absense of sunlight, Arctic ocean under clear skies cools down quickly and freezes into thick ice, during polar night. Why? Because it loses its surface heat, much via IR radiation right up into near-Earth space. Well, if you'd think about it, then you'd realize that this process is STILL happening summer-time, continuously, removing significant fraction of absorbed energy from the surface in short order. The intensity of this heat loss is not anyhow dependant on insolation, it's merely a function of surface temperature and emissivity of surface matherial. It's just that insolation brings in significantly more energy per second than amount lost via IR emissivity of the surface.

So, if you start to crunch 'em numbers of cm/day of ice lost, you can't neglect this and other heat loss mechanisms, if you want to arrive to anyhow realistic figures. Sadly, this kind of calculations takes more than a single small napkin. But one can try, of course. It's just that this topic is not quite the place to delve deeper into this, i suspect.

P.S. Neven, if you're going to snip this post, i'll understand... But IMHO it's better to achieve understanding about this among gentlemen here, which all the above helps to do in pretty short form, given relative complexity of described processes.

123
Arctic sea ice / Re: The 2019 melting season
« on: July 24, 2019, 05:09:00 PM »
...
The melt pressure on the CAA from the north is perhaps unprecedented. Damage is being done, even if extent and area don't take hits.
I saw couple signs that say that you're absolutely correct about the CAA part, lately. And very true about extent and area, too. Apart from (often difficult, uncertain, or not available) measurements of current ice volume / thickness, i'd say small dips in concentration % could sometimes be one useful hint about such processes. I wonder if you use that as one of quick things to check, yourself.

124
Arctic sea ice / Re: The 2019 melting season
« on: July 24, 2019, 04:30:30 PM »
Insolation at 90 degrees is greater than at the Equator until the first week in August.

Ought to settle this question.
Except that the albedo of the underlying surface is in large part a function of the angle of incidence of the solar radiation. This is true not just for water but also for sea ice.


Source: Hudson, 2011 https://doi.org/10.1029/2011JD015804

At 90°N latitude at this time of year the solar zenith angle is about 70° so that all the time is spent in the high-albedo part of the curve. South of 30°N, once the sun rises, almost all daylight hours have a solar zenith angle less than 70° and for much of the day less it's than 40°; at tropical latitudes it can obviously reach 0° at high noon. The end result is a great deal of time is spent in the low-albedo part of the curve.

I have no idea how to quantify this difference. My point is that it's not as simple as calculating the theoretical 24-hour solar insolation based on latitude alone and calling it a day.
Actually there is even more to it. On top of actual effective albedo, there is also the fact that the greater solar zenith angle is, the longer distance sunlight travels within athmosphere, which means not only losses to optical depth of air itself, but also higher chance for any particular photon to encounter particulates and/or clouds on its way to the ice.

On the other hand, the data you present is most likely made using massively simplified idea of "sea ice", both dark and white. I suspect solid 100% concentration sea ice is meant. Well, nearly whole Arctic ocean is now very different from that old normal. Even few % of open water / melt ponds dramatically lower albedo, "slush" and wave action through broken ice does it too.

But since we do basic discussion here - and not a dedicated paper, - i'd say we can safely settle on very approximate range of ~180...300 W/m2 absorbed at the surface under clear skies (high pressure systems) for late July / early August, depending on ice concentration, condition, wave action, etc etc. And that amount is still higher than Florida when averaged over 24 hours, since it's polar day - i.e. sunshine 24/7, while Florida has darkness of the night for significant part of each 24 hours period - during which, for practical purposes, we should count night time as a sort of "negative insolation" value, since surface rapidly loses heat to near-Earth space (clear skies means clouds don't prevent that loss).

So yep, for forum purposes, i'd say we can be quite sure sunshine is still a monster thing for this melt season, and will remain so for couple more weeks; and even after couple more weeks, it won't become non-issue instantly, but will remain serious melting force for few more weeks forward, too.

I hope now this post closes the matter in an acceptable for all of us way... :)

125
Arctic sea ice / Re: The 2019 melting season
« on: July 24, 2019, 04:08:23 PM »
They just don't, in my book. Assuming that the "high" you mentioned will happen not only "oh-so-high Arctic", of course. So, you can not state both in the same time. But you just did. Care to explain? Thank you very much in advance!

Not sure what you are referring to with oh so high arctic. ...
I was referring to regions not oh-so-close to North Pole. Sorry about that, i assumed this to be very clear reference to the figure of speech you youself used in your post i was replying to: namely, you mentioned, quote, "not-so high Arctic". I apology for any confusion caused by my wrong assumption. And in any case, of course there are no hard feelings whatsoever, we do good thing here even on such occasions: namely, building consensus. Salute!

126
Arctic sea ice / Re: The 2019 melting season
« on: July 23, 2019, 04:41:26 PM »
From ESRL here's the melt forecast at +126, when the dipole is about at its worst with strong melt running up along the boundary zone between the two pressure centres.
I wouldn't be surprised the least to see that strong melt along the boundary, but i'd be indeed hell surprised to see as little melt as they project for the center of that high. So yep, i doubt that particular ESRL forecast like really very much. It's like saying "hey 24/7 sun still high enough for most of its energy to reach the surface - means almost nothing in an Arctic melting season". You know? Really hard to "buy", this sorta thing. Except if there is nearly no ice left there beforehand.

127
Arctic sea ice / Re: The 2019 melting season
« on: July 23, 2019, 04:31:07 PM »
I pointed out before there is far more at play than just solar.
"Far" more? As in, solar is kinda not so significant thing? Nope, can't concur. The proper way to say this, IMHO, is "there is more at play than just solar" - drop "far" word for good. Then it's quite correct.

...
According to the ESRL output there is very little top melt expected under the centre of the high.
...
If ESRL says "very little top melt" under July sun in so wet (as it is now) Arctic - then i'd doubt ESRL 1st, everything else 2nd. I mean, when else there would be anything higher than "very little top melt" if not in July under open sun? Next time, they'll probably tell there is "very little melt" in the Arctic whole summer. Yeah. Sure.... Not!

...
Solar will still be a big factor in the not-so high Arctic.
...
I don't quite see how "a big factor" and "very little top melt" compute with each other. They just don't, in my book. Assuming that the "high" you mentioned will happen not only "oh-so-high Arctic", of course. So, you can not state both in the same time. But you just did. Care to explain? Thank you very much in advance!

128
Arctic sea ice / Re: The 2019 melting season
« on: July 23, 2019, 04:12:19 PM »
...
That's a bad comparison
Oh it depends on agenda, though, Friv. In their goal is to create an _impression_ among not-so-bright and not-so-scholarly about the thing being "not so hot", - then their comparison is actually excellent, you know? Using people's common sense of "winter sun is not hot and it's low over horizon", which in fact is a mistake caused by all the heat loss from the athmosphere during every night there in Boston and such places, - quite very smart, you know. ;)

129
Arctic sea ice / Re: The 2019 melting season
« on: July 23, 2019, 03:45:30 PM »
This looks like the Great Arctic Anticyclone with strong winds and waves and clear skies. The sun still be high in the sky. I expect singnificant ice drop in any metrics.

High in the sky ? Under the anticyclone centre area (at 85N) the sun elevation angle will vary between 15 and 25 degrees.

Ok I know the sun does not set but from elevation angle POV, this is something similar to a January 10th afternoon in Boston, Mass.
Why yes, ~20 over horizon is still high, in terms of fraction of solar energy reaching the surface. Which would be something well over 400 W/m2 average, i believe - with ~500 for 25 degrees and something below 400 for 15. This is from the top of me silly head, so please correct if wrong.

130
Arctic sea ice / Re: The 2019 melting season
« on: July 22, 2019, 02:53:34 PM »
As long as sun is still high, sunshine is the worst for the ice in the long term, but the full effect is not immediate. A lot of the insolation goes through the ice and warms up the water below, and some of that heat may remain stored there for weeks. This is the heat that drives bottom melt in late melt season and provides most of the melting power of storms. Thus storms are most effective in melting the ice when they follow a long period of sunny weather.
All correct in principle, but i'd say you underestimate that heat, still, a bit. I'd rather say that the heat _will_ remain stored in the water column - more precisely, signicant portion of it surely will. There is no "may" about it, always happens when significant portion of sunlight gets absorbed dozens meters below surface (which is - always except highly non-transparent near-surface waters). And much of it will be stored for _months_, not just weeks. Affects freezing season, too.

131
Arctic sea ice / Re: The 2019 melting season
« on: July 17, 2019, 04:31:13 PM »
...
If they would make the same arguments as Friv has done here, I'd say: Sure, you have a point. But just basing it on statistics? I mean, what were 2012's chances to reach the record lows it did at this point in the melting season, based on statistics?

I expect more from the number 1 scientific institute on Arctic sea ice. This is just weak.
...
Not just weak; as you rightfully point out, - simply incorrect, since by their approach 2012's chances to do the thing it did were simply 0%.

Now please do one more step, Neven - the step i did ~7 years ago: please do realise NSIDC is _not_ #1 scientific institute on ASI. #1 political institute on ASI? Perhaps. But not #1 scientific. It is (by far) not the 1st time those guys publish incorrect judgement, and it certainly won't be the last.

P.S. Please get me right: i do not doubt their scientific qualification, i doubt their sincerity. If you deem this far-fetched - simply ask yourself: how much scinetific qualification it takes to understand that the thing they posted is not, in fact, correct? How likely it is they don't have that much (or should we say, that little) qualification to make such a mistake honestly? Answers are quite obvious...

P.P.S. This post is not in any way to "blame" NSIDC about anything, too; the way i see it, they are forced to follow certain rules in there, for which price they then have the means to perform highly important research and produce potentially life-defining results. I will be the last guy to blame NSIDC personnel about doing any "wrongs", for sure.

132
Arctic sea ice / Re: The 2019 melting season
« on: July 16, 2019, 05:28:36 PM »
Clear skies at the pole.  Shot is centered on the North pole. 30°E is straight up. One pixel is just about 375m.

16 hour loop, "natural color"
Click to run
Using this calculator, i see that now (day 196) surface albedo of ~36% would mean equilibrium surface temperature of ~1°C there at the North Pole from insolation alone (before any greenhouse effects). Same calc lists ice albedo as 60%, water albedo as 6%. For the latter, equilibrium surface temperature would be ~29°C. And the place looks rather bluish, to me.

133
Arctic sea ice / Re: The 2019 melting season
« on: July 10, 2019, 03:11:19 PM »
Could any of this anomalous warming in the ESS and Alaska be from localized methane emissions? How soon does methane contribute warming once released?

<Edit Neven: Ask questions like this one in the 'stupid' questions thread, or the methane thread.>
...

<Edit Neven: ... No, it shouldn't be discussed here, because this thread is for near-real time monitoring of conditions in the Arctic. If you can point to reliable near-real time data graphs or maps that have a direct influence on the outcome of this melting season, and that can be compared to previous years, please do so. If not, take it up in other threads.>
Understood, appreciated!

I can "point" to it indeed - the guys who did this neat animation (press "play" button in the bottom right corner; it takes a bit to load) seem to have plenty good data on the subject. And those fellows are quite reliable bunch. But for now i am unable to "compare to previous years" due to particularities of data retrieval they offer. But perhaps someone else can do it for us here?

And please allow me to just briefly answer Oscilidous' questions, as these answers can help more than just him, i'm sure. I promise i won't go any further on this topic, too.

1. yes, quite some of that high heat could well be caused by local (regional) methane emissions, since methane's local warming potential is ~1000 times higher than CO2 and as you can see from the 1st link i gave just above in this post, both Alaska and ESAS have significantly elevated methane levels presently.

2. once methane reaches athmosphere - it starts to contribute extra warming instantly, as surface always emits IR (sunny days more, cloudy days / nights less) and methane is rather dilute presently, means every molecule is pretty effective at adding extra greenhouse effect; some technical info about how it all works can be found here.

134
Arctic sea ice / Re: The 2019 melting season
« on: July 09, 2019, 05:01:19 PM »
Could any of this anomalous warming in the ESS and Alaska be from localized methane emissions? How soon does methane contribute warming once released?

<Edit Neven: Ask questions like this one in the 'stupid' questions thread, or the methane thread.>
With much respect, Neven, i have a related (to the above) question, for which i invariably need a certain much-more-than-5-lines length. Apologies. Complex issue, you know.

The question is: do you personally think that given the following data, interaction between methane emissions in ESAS (at least; possibly other arctic shelves) and local sea surface temperatures (and thus, sea ice melt rates) - should be discussed, among other things, in this here Melting Season topic - and, if you do not think so, then why, exactly, it should not be discussed here?

<Edit Neven: snipped a lot of text that clogs the thread. To answer your question: No, it shouldn't be discussed here, because this thread is for near-real time monitoring of conditions in the Arctic. If you can point to reliable near-real time data graphs or maps that have a direct influence on the outcome of this melting season, and that can be compared to previous years, please do so. If not, take it up in other threads.>

135
Arctic sea ice / Re: The 2019 melting season
« on: July 09, 2019, 03:45:09 PM »
For those interested in more details on volume, I've just posted PIOMAS July 2019 on the ASIB.
Much appreciated, sir. Slight note on wording there, PIOMAS section: instead of "escape the grey bands of standard deviation", i'd rather say "escape the lighter-grey band of 2nd standard deviation", unless it's wrong to think that each color corresponds to one standard deviation (i do). And to answer your question at the end of the piece: why, it's likely 2019 will beat 2012, due to simple consideration: volume (and thus amount) of ice is on par for the moment, but pace of the melt is greatly higher for 2019. Continue the trend, the answer is obvious. Of course, weather "may" have a say and "override" the trend, thus only "likely" above - not more. I guess that's the best answer there may be, at this time.

136
Arctic sea ice / Re: The 2019 melting season
« on: July 05, 2019, 05:06:02 PM »
... One huge blob of moisture is being pushed from Eurasia via the Kara to rotate north of Svalbard, with surface temps around 2C, while the Alaska and Chukotka heatwave pushes warmer air and more moisture in from the Pacific. The melt over the past few days has been very aggressive on that side as we see in the Bremen animation, and that's only going to continue, if not worsen. (Warm?) rain and a lot of longwave radiation, as well as very high SSTs close by
...
And while those systems push warmth into the Arctic, the cold air spills out of the Arctic southwards elsewhere; in particular, Moscow (Russia) is going through a series of record low air temperatures since the end of June, some days being ~12°C tops (which normally is a kind of weather of end of September for the area, rather than end of June / beginning of July).

This is not the 1st time Arctic loses large amount of "coldness" via losing air masses to temperate belt, and every time it happens i think proportionally large extra warming hits the Arctic as well (with everything else being equal). Jet stream weakening in action...

137
Arctic sea ice / Re: The 2019 melting season
« on: July 03, 2019, 06:05:03 PM »
Rutgers Snow Lab has June Northern Hemisphere snow cover fourth lowest on record:
Thanks for sharing, Neven. I've been saying about a month ago in the thread that i see snow cover being catastrophic, wondering if it's just me; and here we go - bad enough to be named so, given the circumstance of higher overal temps around Arctic parts in '19 than it was in '12, which with everything else equal means a bit faster melt for remaining snow. Of course, it's even more important in what condition snow is near mid-june - more than even snow covered area per se, i mean; but usually when it's large negative anomaly, lots of remaining snow cover is wet and darker than normal, i bet you catch my drift.

I called one of recent seasons "soupy" because of all the fragmentation. This one feels quite "soaked", both ice and snow. We'll see...

138
Arctic sea ice / Re: The 2019 melting season
« on: June 26, 2019, 03:13:31 PM »
And the last few winters were at worst bad for freezing, and at best they couldn't reach a level of regeneration that could turn thin, fragmented ice to the solid ice that was the rule a decade or two before.

In the end, the question is, would we continue to be lucky to not get a strong melt season until the ice returns to its previous levels, or would we get a new record low instead. Unfortunately, the second option seems way more likely.
Sorry for double post and kinda off-topic, but this one made me **really** curious! Dear AmbiValent, would you very kindly tell us here, what exactly makes you think that "ice returns to its previous levels" situation would actually happen in any observable future? I have a guess, but i'd really like to hear what you gotta say. And if you'd prefer not to answer this question - then please say so. It'd be hint enough in itself. Thanks!

139
Arctic sea ice / Re: The 2019 melting season
« on: June 26, 2019, 03:01:17 PM »
...
   Z Labe's arctic monthly graph shows 2005 was the warmest June recently with 2007 and 2012 (funnily enough) lying 2nd and 3rd . ...
... It should be noted that:

2005 set the record low sea ice area/extent.

Until.....

2007 set the record low sea ice area/extent.

Until....

2012 set the record low sea ice area/extent.



BUT JUNE ISN'T THE MOST IMPORTANT MONTH?????
Yup.

They'll tell you your numbers are fake, your sources are bad, your brain is damaged and your doubt in their intellectual superiority is criminal offense punishable by hanging, too. If you'd let them. :D

140
Arctic sea ice / Re: The 2019 melting season
« on: June 26, 2019, 02:18:16 PM »
...
further, even though extend wise we have not seen a new minimum, we have seen minima in volume and been very close to the record in 2016 and last but not least the ice has been preconditioned over the last few years
...
The situation when volume is record low while extent is not record low - is actually worse than when both are record low. Because such situation means lower thickness, and lower thickness means extra damage to the ice during a melt season via more cracks forming, greater damage from wave action, less optical and thermal insulation which ice gives to the water directly below it vs sunlight, and faster disappearance of thinner ice under GAC-like conditions.

141
Arctic sea ice / Re: The 2019 melting season
« on: June 25, 2019, 05:39:08 PM »
Spot on, Friv. But say, don't sweat it a smallest, though. Seems we have a fella who sees no connection between before-solstice melt ponding / albedo drop and September minimum. Nor between before-solstice melt - as in greater amount of solid known as "ice" turned into liquid known as "water', - and "ensuing minimum". That, or he does see those things alright, but _claims_ not to - which is even more laughable.  "No correlation", he says. Perhaps someone from Comedy Club? Hehe. Either way, i bet nobody serious ain't buying it-and-such, eh.

142
Arctic sea ice / Re: The 2019 melting season
« on: June 25, 2019, 05:08:49 PM »
My posting said the dates. June 15 for vol and thickness june 19 for area. Merely required the ability to read.
So did the graphs in the Jim's post, which clearly show the growth starting ~10th June, not 15th. So, area and extent between ~10th and 15th are shown as sharply increasing, while volume is not. Oh and Jim, i did not say you said those graphs would suffice, too. It was somebody else who seemingly did such a judgement well before you posted, you know. Certainly your post only helped to make things clearer, in my opinion, so yep, i'm just thankful.

143
Arctic sea ice / Re: The 2019 melting season
« on: June 20, 2019, 06:45:09 PM »
Ah, there we go, beautiful, gerontocrat! So do my eyes decieve me, or do i see "amount" of ice ain't going anywhere one could name "up", on 2nd of those beautiful graphs? I'd say well within known error margins, that hiccup. So perhaps reaction of some forumites to the above "more ice in general in that location" is simply because that's one statement which goes against what those folks know must have been happening there? Like, June 20th, "more ice somewhere in NH" sounding... Silly? ;)

144
Arctic sea ice / Re: The 2019 melting season
« on: June 20, 2019, 06:37:09 PM »
...  Parallel and clear trends in changes in area and extent over the past 10 days?  Yes. ...
Yes, the trend as it was in the past - is clear. This year breaks it. Means something different is going on. Means old "rules" may well not apply anymore. And to your question - if something's going on, i'm unawares; merely commented the content, did not comment the person. I always do that. If Santa dear Claus, best friends of kids whole world around, will come in here and say all kids are to be killed on sight, - heck sure i'll comment negatively, not paying no heed to "who" he is. Same.

145
Arctic sea ice / Re: The 2019 melting season
« on: June 20, 2019, 06:32:37 PM »
The weather models are basically shocking.

Day 1 through 4 see a huge Ridge over the Pacific side very bad for the ice.

But around day 4 this Ridge becomes epic level expansive.

Like what the fuck.

That is all

Whoa. When Friv is stunned into writing short, simple sentences with no wildly descriptive adjectives, that scares the shit out of me. I may not know how to read the weather, but I know how to read the Friv.
Same. Very well put, too.

146
Arctic sea ice / Re: The 2019 melting season
« on: June 20, 2019, 06:11:16 PM »

Look at both the extent and area charts for Beaufort.  They both jumped up.  So not more dispersion, just more ice in general in that location.

Michael Hauber you should be ashamed of yourself.  This is an absolutely incorrect and misleading statement that is contradicted by several images posted above from hard working people who are trying to accurately describe what is actually happening right now.

The high resolution extent and area charts for the Beaufort Sea:
Thank you, Jim, but it just happens that those graphs are utterly insufficient to properly estimate amount of ice there. Amount of ice is defined not just by extent and area, but by the combination of area and thickness (and extent is really not needed). Thickness is missing here.

Besides, each of those measurements is the subject for large uncertainties, especially during melt season. For example, i don't deem it impossible for a satellite / data processing to detect an increase in both area and extent if it's actually a layer of slush, produced by melting ice and significant wave action. Another possible erratic detection of area / extent increase, as mentioned in the forum many times, is when previously on-ice melt ponds get drained into the ocean en masse. Etc.

How on Earth anybody would properly conclude "more ice in general in that location" based on those couple graphs only - i honestly don't know. "Suspect"? Sure, doable. "Likely"? Perhaps. But for sure? Hell no.

147
Arctic sea ice / Re: The 2019 melting season
« on: June 20, 2019, 05:18:33 PM »
...
The forecast shows at least six more days of worsening conditions (read: higher pressure over a larger part of the Arctic), and as others have noted, the forecasts after D6 look truly abysmal. We can only hope that the models have it wrong.

Solstice is tomorrow...
No, we can do not only that. Namely, we - more precisely, some of us, - may actually hope the models are right. I do, for example. More, i think you should, too. Lately, i came to conclusion that the sooner global industrial will go belly up, - the better. Indeed, it being the most responsible entity for the process of dehabitability (for humans) of large portions of this planet, the sooner it'll go - the better. So, i weep about all the lives which will be lost - but i applaud Blue Arctic in the same time, as the sooner it happens, - the _less_ lives will be lost in the end. Future generations, you know.

148
Arctic sea ice / Re: The 2019 melting season
« on: June 19, 2019, 04:33:31 PM »
~3 days ago, coords ~81.1, ~51.1: https://dmitry-v-ch-l.livejournal.com/262525.html. Counts as 100% extent eh.

149
Arctic sea ice / Re: The 2019 melting season
« on: June 05, 2019, 03:25:52 PM »
No, I can't, no matter how hard I squint. It's mostly based on gut feelings, and some experience over the years. I haven't looked properly at how 2019 came out of the freezing season, and then there's ocean heat flux as well.
Copy. Then perhaps A-team or someone could do it. I'll hope.

Meanwhile, Barrow sea ice camera shows quick disappearance of snow and ice remains on shore yesterday, despite very little direct sunlight present there yesterday - looks like less than half an hour - i see the definite shadow only once in the last 24-hour time lapse.   

150
Arctic sea ice / Re: The 2019 melting season
« on: June 05, 2019, 01:22:19 PM »
...

My interpretation for May 16-31:
2012 lost the most volume, mostly because of a strong Dipole. 2010 and 2019 are on a par. 2019 has higher pressure (but again centred near Greenland), but 2010 has all the anomalous heat along all coasts. I would've guessed volume loss for 2016 would be higher, but maybe just not enough high pressure and anomalous heat.

BTW, this is high-level eyeballing. I may have to buy a pair of glasses now.  ;)
Pretty-please do buy 'em, sir. Because i have a question to you glasses could well help answer. Namely: the bolded part in the above quote clearly means (to me) that 2019 melting potential is greatly higher than that of 2010 (since it's harder to melt things in CAB than along the coast, where it's often fractured, thinner, closer to melting point initially, etc) - so, can you anyhow quantify this? I.e., can you anyhow napkin-calc how much harder it'd be to melt an amount of ice "near Greenland" than to do it "near the coasts", 2nd half of May?

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