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Messages - seaicesailor

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1
Arctic sea ice / Re: Home brew AMSR2 extent & area calculation
« on: March 29, 2017, 03:12:51 PM »
There might have been some rain or a brief period with conditions near zero, which at least affects the snow blanket. Not as bad as contrasting implies, but it may qualify as pre-pre-conditioning (half kidding)
Edit. Well there you go, thank you Wipneus

2
Arctic sea ice / Re: The 2017 melting season
« on: March 28, 2017, 06:50:07 PM »
If PIOMAS captures well all the melting that has been going on west of Svalbard, I don't think the volume increase will be in the high range.

What seemed to be a decent block 120 km long and about 50 km wide at widest point, disappeared in just couple of days. Of course it's not surprising, as the warm current has been there for a very long time.
Yes, and I wonder how permanent this is (the warm currents this strong). Can the ice affect the currents somehow in short term? I would say no but locally they may force the salty water sink in a more southernly location permitting the ice pack extend more... or just the opposite reinforce them for this summer (after all more sinking is one of the engines that drives more water from South)

3
Arctic sea ice / Re: The 2017 melting season
« on: March 28, 2017, 05:47:11 PM »
If PIOMAS captures well all the melting that has been going on west of Svalbard, I don't think the volume increase will be in the high range.

4
Arctic sea ice / Re: The 2017 melting season
« on: March 28, 2017, 05:13:11 PM »
ACNFS Hycom Sea ice drift predicted from today to Apr 2.
The situation reminds a bit to Spring 2014, with the ice drifting away from Laptev sea coasts persistently, and a lot of transport toward the Atlantic.

5
Arctic sea ice / Re: The 2017 melting season
« on: March 27, 2017, 09:20:45 PM »
BTW when I said absence of cracks in the American side I meant mostly the Beaufort sea. As seen in that pic posted by A4R, north of the CAA and Greenland is a complete different story, but the danger there is not so much insolation but mobility of the ice toward the Atlantic ocean as explained by A4R.
Well, insolation too, eventually   :-\

6
Arctic sea ice / Re: The 2017 melting season
« on: March 27, 2017, 12:14:42 PM »
I think that at this time, all new cracks refreeze, but will easily re-open soon (1 month?) and absorb sunlight with a very negative impact on ice for the whole summer, which overcomes any beneficial heat loss. It would be a different story if this happened in January.
Likewise, the absence of cracks on the American side for the time being is certainly a positive for the ice.

7
Arctic sea ice / Re: The 2017 melting season
« on: March 27, 2017, 12:45:25 AM »
Tropicaltidbits has a nice visualization of NOAA long-range CFS model and that is always interesting, even when the skill of this model in the Arctic is been challenged in the past and we must take the predictions with a grain of salt.
These are the weekly ensemble average of a large number of runs, of pressure and temperature.
Focusing only on the persistent features, the MSLP shows that the large low pressure anomaly finally gives way to a more usual pattern in April with a high in Beaufort and a normal flow south from the Eurasian continent toward Fram thru the pole.
This translates on temperatures that are going to be anomalously high in all Siberia and all Eurasian Arctic Coast. Anomalously persistent warmth in most of Canada too, coincidentally or not. A lot of snow in both continents might start suffer decimation.
Coldness persists on Nansen basin and Greenland sea, which is associated with the northerlies that unfortunately for the MYI will keep moving it inch by inch toward the Atlantic.
Only good news for the Bering sea.
What will happen with the Beaufort sea persistent high. Repeat of '15 and '16 ?
In general not good for the Arctic but that news as usual. All of this may well be crap (1008 hours of forecast!) but it is always enjoyable to speculate some especially when more crucial moments for the menting season is about to start.
Time will tell

8
Arctic sea ice / Re: The 2017 melting season
« on: March 25, 2017, 01:34:28 PM »
Thanks for the info about bouy Jim.
Strange location to place that buoy, being short of funding they risk to gather like .... four months of data.
Who knows, last year Laptev sea ice, a usual "goner", did not completely melt being less than 2m (and 1m much of it) FYI. It was sealed, was cloudy and cold, it is the closest example I can come up with of the importance of (absence of) albedo feedback.
I guess this is what makes the 60% of that paper :P

9
Arctic sea ice / Re: I'm updating the ASIG next week. Any tips?
« on: March 25, 2017, 01:20:27 PM »
Hey Neven, thee SST page of DMI is now throwing what I believe ice temperatures as well, while the link to ice temps you have does not show an updated map and just links to the DMI in general.
Just in case you want to check it out. I think you can safely throw away the second link and gain some space.

10
Arctic sea ice / Re: The 2017 melting season
« on: March 24, 2017, 02:28:31 PM »
Three animations taken from one of Worldview's sea ice concentration layers (AMSR2 12 km resolution), of the last thirteen days.
First one shows the retreat of the ice at Kara sea.
Second one shows the dispersion of the ice over Fram, Svalbard and Barents in general. In the last two frames, some retreat (or rather melting?) of the ice  near Svalbard and Fram can be observed,
The last one shows an interesting feature forming in Bering sea ice edge during the last few days, its formation not following the general drift of the ice at Bering sea. This is a wedge-like intrusion of ocean that is trying to reach the Bering Strait, more aligned with the Asian coast. Hycom shows ocean flow in that location and direction precisely.

11
Arctic sea ice / Re: The 2017 melting season
« on: March 22, 2017, 11:33:54 PM »
Anyway I remember maps with similar positive anomalies last year in Eastern Siberia and disappeared pretty abruptly. In fact a heat wave in May or June started last years ESS bite. Its really unpredictable.
Models hinting for that Beaufort high forming in five days and coupling with a strong Laptev low for two or three days. We may see some wind-driven sea ice drift clockwise in the Beaufort sea after all ( though the underlying Gyre ocean current seems dead to me, not the slightest displacement this year so far).

12
Arctic sea ice / Re: IJIS
« on: March 22, 2017, 11:08:46 PM »
Instagram, sepia filtering...
No idea ; P
Nice plots!

13
Arctic sea ice / Re: The 2017 melting season
« on: March 22, 2017, 04:18:44 PM »
From last entry of Judah Cohen blog, this speculation I think of interest here, worth being taken into account. Interesting that he does take as valid the excess in accumulated snow (depth, not extent) in Siberia and Canada shown by the models.

Longer term, the global environment favors mild temperatures for the coming months.  The Arctic remains exceptionally warm, aided by record or near record low sea ice; land and ocean temperatures also remain near record warm temperatures.  The only boundary forcing that I can think of that may contribute to relatively cool temperatures is snow cover across the NH.  The amount of snow covering (in mass not extent) the NH is the highest observed over the past twenty years or so.  I hope to be able to tweet out this week a graph of the snow mass this winter across the NH.  A deep snowpack across Canada and especially Siberia will retard warming at least across the high latitudes of the continents that may be transported episodically to lower latitudes.

https://www.aer.com/science-research/climate-weather/arctic-oscillation

14
Arctic sea ice / Re: Stupid Questions :o
« on: March 22, 2017, 12:30:22 PM »
Thank you Jim and epiphyte
They love their fossil fuels as much as any GOP member. They love their guns; they love their version of "small government". They just thought their Party was silly to ignore the obvious, but that wasn't enough to drive them away...
I think this explanation makes a lot of sense. Thanks

15
Arctic sea ice / Re: Stupid Questions :o
« on: March 21, 2017, 11:48:30 PM »
I have a really stupid question from a long time ago and it is, if in Alaska in particular, the warming is say three or four times or more than average global due to Arctic amplification, the impact on environment must be brutally obvious... in half a a decade (not two generations) then why it keeps such a heavy Republican place in majority?
All respect to any individual from Alaska.
Neven feel free to move this elsewhere, just wanted to let the question out.

16
Arctic sea ice / Re: The 2017 melting season
« on: March 21, 2017, 08:30:10 PM »
Thanks LMV.
Too see the Atlantic currents break thru the ice is going to be an spectacle, a lot of thick ice already sitting on top of the Spitsbergen current for instance.
The forecast shows also high pressure system wanting to stay over Beaufort, let us see whether that realizes and especially persists, in which case it would be dangerous to Beaufort sea ice in April.

17
Arctic sea ice / Re: The 2017 melting season
« on: March 20, 2017, 04:43:20 PM »
Before we get too deep into melting season, would some of the more seasoned posters mind giving a handful of things they will be keeping an eye on over the next few months to judge how 'good' or 'bad' the melt is going?


5 fingers worth to start with? Not necessarily in order of time or importance!

1. How soon melt ponds and/or open water hang around in the Beaufort Sea this year. Things started very early last year:

http://GreatWhiteCon.info/2016/04/the-beaufort-gyre-goes-into-overdrive/



Suscrbe all points, emphasizing this one because for the time being weather is being favorable to Beaufort sea ice (relative to last year) .All can change in April obviously

18
Arctic sea ice / Re: The 2017 melting season
« on: March 19, 2017, 06:06:06 AM »
Among other places, it looks like there is melting and thinning out of ice within parts of the CAA.

With current temps there, I doubt we are seeing any thinning out in CAA. More like the usual thickening-in I'd say.
Kara otoh is going south pretty quickly this year.

19
Arctic sea ice / Re: Poll: 2017 PIOMAS Maximum Monthly Figure
« on: March 16, 2017, 06:23:30 PM »
Hasn't ever not been April for highest month on record.

There has never been better conditions for a March highest average month.

Remember we are talking highest monthly average, meaning you are also betting on a significant amount of ice sticking around until MAY.
Most of ice of the Arctic proprr keeps thickening until June, regardless if later it melts precipitously or not. If the daily average temperature stays under -2C, sufficiently far from the edges, the ice layer keeps growing at the bottom, and even when it goes above freezing it takes a while (some days) for the heat to reach the bottom and this stop growing. Something Jim Hunt shows in the forum neatly every year with the buoy data.
I don't think the anomalous warming is still enough to displace the volume max a whole month, but we have been witnessing pretty weird things so...
Edit. Now that we are at it I found the animation of 2015F temperature data last year. This infelice buoy was in the CAB (toward Beaufort sea) and did not see bottom melting until end of June, its surface melting being a few centimeters I think before dying for unknown reasons

20
Arctic sea ice / Re: Poll: 2017 PIOMAS Maximum Monthly Figure
« on: March 16, 2017, 01:27:30 PM »
The 1979-2016 average monthly increase from February to April is 3.058 k km3, so adding 17,400 we have a total of 20,458 km3.

I choose the 20.25-20.75 km3 range.  ;)
+1

21
Arctic sea ice / Re: The 2017 melting season
« on: March 16, 2017, 12:16:12 PM »
I wouldn't count with that 956mb low... just mentioned to keep an eye. It is still in fantasy-land. Peobably the general circulation will hold though.
The 970mb storm just hitting the door is nasty enough

22
Arctic sea ice / Re: The 2017 melting season
« on: March 16, 2017, 10:46:12 AM »
The ECMWF has entered into loop mode and predicts for day 10 another bomb storm entering the Barents and displaying similar circulation to the current one about to mess things up.
Everything can change but worth keeping an eye.
In the Pacific side all seems quiet and nice except for the fact that ACNFS is foreseeing an activation of Bering inflow, probably due to persistent lows over Aleutians (will post animation later)

23
Consequences / Re: The impacts of sea level rise around the world
« on: March 15, 2017, 04:22:21 PM »
A few months old report but kind of fits, the text of the link is a good summary

https://www.scientificamerican.com/article/sea-level-rise-swallows-5-whole-pacific-islands/#

24
Arctic sea ice / Re: Stupid Questions :o
« on: March 15, 2017, 02:40:25 PM »
Let me phrase my stupid question a slightly different way.  What evidence do we have that we are using the right kind of mathematics for predicting what will happen in a discrete discontinuous system over a long period of time?  (Long being over about a month.)
Kinda rhetorical, Jim, but we don't. What we have is the output of the models themselves.

I really don't think the reduction of skill with time is a result of the math. I think it is a result of the inputs, their granularity, and our understanding of the system mechanics.

I'll agree that right now the major error is our lack of data on the initial conditions, with lack of understanding of the mechanics coming in a close second, but it still seems to me that using a math which models temperature as a continuous "Real" variable rather than as billions of discrete changes will simply never be able to make accurate long range predictions.  Discrete Topology simply isn't the same math as continuous vector fields.  In particular, the group of Integers has all sorts of funky subgroups and other properties that only show up with very large numbers.
You must be a god if you want to abandon the thermodynamic equillibria assumptions  and try solve the underlying discrete quantum equations with 10^26 or more degrees of freedom... to end up getting similar results because the thermodynamics models have been working really well for centuries.
Do you know that in every breath you take there is a 99.99% probability of you taking at least one molecule of air that Caesar expelled when he said "et tu Brute"?
I think climate and weather models are well above the head of most of us here and I personally let specialists do their job and deliver their breakthroughs when they come with one.

25
Arctic sea ice / Re: The 2017 melting season
« on: March 15, 2017, 10:42:45 AM »
But wasn't kind of obvious from these past years? We can pick the paper, find/replace Laptev by Beaufort and submit a new paper... ;P
Just kidding, maximum respect to their work

26
Consequences / Re: 2017 ENSO
« on: March 15, 2017, 12:11:56 AM »
Thank you ASLR.
It's March, excessive rains have continued pouring in many regions after January, media keep calling it el Niño. Hoping it abates and does not merge with another real Niño.

27
Arctic sea ice / Re: The 2017 melting season
« on: March 14, 2017, 08:39:00 PM »
I must say my confidence in ACNFS thickness has grown this freezing season, some late tweak in 2015 or 2016 must have improved it since it is not so far as it used to wrt Cryosat and PIOMAS (granted there are differences). Similarities as well with the AMSR2-based product in the shape of the old ice, with ASCAT patterns etc. The same I DON'T feel about the DMI HYCOM.
I doubt the confidence will remain during summer.

28
Arctic sea ice / Re: The 2017 melting season
« on: March 14, 2017, 05:11:19 PM »
Looking closely thru the ECMWF to the "yet another" bomb storm from the North Atlantic in four- five days, I think it is going to make puree. And it comes with friends from Norway Kara and the now native or permanent resident of the Arctic. Storms unleashed until when.

29
Arctic sea ice / Re: Stupid Questions :o
« on: March 14, 2017, 02:37:15 PM »
My stupid question of the day:  Are there any climate models out there that use system dynamics rather than trying to model a natural system for any length of time by pretending it is a linear vector space and using arrays of differential equations?
It is difficult to understand the question Jim, because I see both options you give as equivalent. An array of differential equations applied over a vectorial quantity ("linear"?) or several scalar and vectorial quantities, can be a mathematical model of a dynamical system, suitable for performing computations and developing predictions of the underlying dynamical system.

30
Consequences / Re: 2017 ENSO
« on: March 14, 2017, 12:21:42 PM »
May I ask why so warm in el Niño 1,2? Does this reflect a different phenomenon than el Niño? Cause in Perú they have a bad feeling. Just curious, may somebody following this know.

31
Arctic sea ice / Re: The 2017 melting season
« on: March 14, 2017, 10:32:20 AM »
Yep. Mean temperatures won't be telling half of the story. Kara, Barentsz, Okhotsk, Bering seas suffering anomalous temps especially that wave coming from Eurasia according to GFS (0 -168h forecasts below). The low will be pulling and pushing, with a well defined front of temperature. Those cracks along the Asian coast will eventually  refreeze but chances are we are going to see them a lot in Tealights maps come May.
The only part that is faring well is the young ice of the Beaufort sea at the moment. Quiet and cold.

32
Arctic sea ice / Re: The 2017 melting season
« on: March 13, 2017, 08:39:29 PM »
Btw, Neven, "sis" is usually a colloquialism for "sister". Although I'm sure seaicesailor wouldn't be offended by the monikor.
LOL
I didn't notice (not native in english tongue) so fine with me.

33
Arctic sea ice / Re: The 2017 melting season
« on: March 13, 2017, 03:53:52 PM »
I've been looking at ASCAT radar images and saw some interesting features. Here's an animation for the past week, and those features are in the first frame (white circle and rectangle):



Usually, dark means thin in radar images, and these features have been there since November. The one in the circle looks especially interesting, but I don't know if it means these regions are  thinner. And I haven't compared to other years yet either, but I thought I'd throw it out here to see what you guys think.
FYI and FYI according to the russian service that you point to in the ASIG, Neven. The elongated structure seems trapped FYI between the two surviving arms of ice in September, and the other region has been growing in extension as the surviving ice drifted northwards.

34
Arctic sea ice / Re: Latest PIOMAS update (March)
« on: March 09, 2017, 04:27:38 PM »
Anyway, so the topic doesn't derail again into awful nonsense, I am quoting Wipneus's thickness map updates, which have been lost in the crap:

Here is the animation for February.
This month I present the thickness maps for the last day of the month, instead of the mean monthly map. Should be more relevant.
Here the thickness map for 28 Feb 2017, comparison with previous years and differences with previous years.
What I find quite interesting is that the first year ice in the Beaufort this year is actually thicker than it was last year. Has Beaufort been cooler this year?
A lot of the thin FYI in Beaufort appeared in fact in 2016 during February so it was few-days-old ice. Product of ice drift opening up gaps along the coasts and refreezing immediately. Like Laptev sea this year.
Well, this year there is no drift due to Gyre, no Gyre to speak of, I guess it has been mitigated by so many storms

35
Arctic sea ice / Re: The 2016/2017 freezing season
« on: March 08, 2017, 01:55:25 PM »
Seaice: If Piomas is right about the location of most of the last thick ice, and if that drift forecast is correct, a large volume of ice is just about to get a good push towards the Fram exit.
Yes, i agree, and ice melting near Svalbard and Greenland, probably why Feb volume anomaly stayed flat, regardless of the faster refreezing of late Feb. and the constant drift, refreezing and accumulation of ice at ESS.
This push is actually starting now but not clear it will persist much into next week.
Besides wheres A-Team cry, we should shout "where is the Gyre?" Or "Lo the Anti-Gyre!"

36
Arctic sea ice / Re: The 2016/2017 freezing season
« on: March 08, 2017, 10:54:17 AM »
A nice storm centered in the Arctic by Sunday (ECMWF) and the ACNFS drift predicted for same day.

37
Arctic sea ice / Re: The 2016/2017 freezing season
« on: March 02, 2017, 11:29:45 AM »
Thought people might find this interesting... Beaufort yesterday vs. this time last year (i.e. mid-crackopalypse)...
Last year, there was actually something to *crack*, and other bits of it which were solid enough to resist.

Everything there is FYI, and most of it less than 1.7M; if it gets stressed, it breaks, and spreads out the force, rather than transmit it.
In my humble opinion, there has not been appreciable ice moving compared to the same date last year. If it stays quiet until June, will be healthy. That's a big IF anyway.
This is consistent with the observation that a predominantly low-dominated Arctic weakens the Gyre. Weakening of the Gyre stop positioning MYI in the Beaufort Sea and creates no ocean gaps far so easy. This might be considered as being a negative feedback due to a wetter and stormier Arctic (positive for ice rebound); other negative feedbacks of storminess could be later refreezing, greater accumulations of snow in winter and spring, and overcast skies in May and June.
Right, I commented along similar lines the other day but the thing about the snow is a double edged sword as most know here.
And I never found the late freezing negative feedback all that convincing, but if there is a year with a very late refreezing in the Pacific side, this is it. Will be put to test.
Out of curiosity why stormier Arctic in Fall/Winter is related, or comes hand in hand with a stormier Arctic in Spring/Summer?

38
Arctic sea ice / Re: The 2016/2017 freezing season
« on: February 23, 2017, 11:51:26 PM »
The Beaufort and Chukchi seas will be entering March completely devoid of multi year ice, in danger of a swift runaway of meltout. Will it happen this year?
A reactivation of the Gyre would bring MYI from the CAB but also openings along the coast with bad consequences. A more static situation leaves us with thickening FYI and no open waters... interesting.
ACNFS predicts for the 28th some modest detachment of drifting ice from the coasts West of Barrow, nothing more, but we'll see, ice looks fragile. Thickening progressing fast now. It is pretty early yet.

39
Arctic sea ice / Re: The 2016/2017 freezing season
« on: February 23, 2017, 08:59:33 PM »
We remain on topic here :)
ECMWF and GFS show just a meager warming of Western and Central Arctic within the next 7 days. Even gets some cold air displaced from Greenland and Siberia.
However the Atlantic side gets blasted once again.

40
Arctic sea ice / Re: The 2016/2017 freezing season
« on: February 23, 2017, 04:26:54 PM »
Another lurker who has read this blog for years. This topic is dead. The melt has begun. The past 2 days have seen some serious ice disruption (satellite visual imagery). I have not yet checked the daily image posts, but likely some eye openers for everyone.

sea ice grows from the bottom until summer (for most of the Arctic ocean)
melt has never really stopped this season, the effect of the Atlantic currents flowing by the north of Svalbard is really strong.
 http://forum.arctic-sea-ice.net/index.php/topic,1611.msg101832.html#msg101832

41
Arctic sea ice / Re: The 2016/2017 freezing season
« on: February 21, 2017, 08:21:48 PM »
Look at that sustained Fram export btw, and to balance, the losses in Bering sea.

42
Arctic sea ice / Re: The 2016/2017 freezing season
« on: February 21, 2017, 08:11:57 PM »
ACNFS now picks the effect of the high forecasted over the Pacific side of the Arctic for the next six days. We may see open water near Barrow and maybe Amundsen bay. Curiously, the big gap that had opened in January in ESS will be stuffed with thicker ice now.

43
Arctic sea ice / Re: The 2016/2017 freezing season
« on: February 19, 2017, 11:37:39 PM »
Might that high cause a cracking event (albeit not as big as the one in 2013)?
It will be interesting to evolve toward the summer with similar FYI (although thinner) in the Pacific half of the Arctic as 2013 but a different weather.
To start with the departure, early opening along the Alaskan coasts in Feb-April like last year rather than cracks in the middle of the pack. I guess the strong high forecasted can cause either. But the ice is still really thin in some areas of Beaufort sea particularly close to Barrow point

44
Arctic sea ice / Re: The 2016/2017 freezing season
« on: February 19, 2017, 04:08:16 PM »
TT you put too much confidence in that product.
I guess you mean the Wipneus chart derived from JAXA data. It comes into use. But I look at several products combined with common sense to make a conclusion...
I know, sorry if I sounded condescending.
Wipneus calculations are reliable, what I mean is the ice thickness from ADS NIPR or JAXA is not. It gives valid information but varies at the mercy of air temperature fluctuations, precipitation, and who knows. My honest opinion.
Below the averaged isobars for the next five days. Sustained transpolar drift, 40 or 50 km of accumulated drift at the Pole during these five days, make it double or triple around Fram and Svalbard, with that storm coming. A bad moment for the ice pack be broken into hundreds of floes.

45
Arctic sea ice / Re: The 2016/2017 freezing season
« on: February 19, 2017, 03:24:16 PM »
That gives a glimpse of the old CAB. All that export, and yet concentration and volume both are growing. I don't have any false hopes that it will last, but it's good for it to have at least one last hoorah for the season.

While I don't doubt volume should increase with the colder weather I find it hard to believe volume is greater than this time last year when FDDs this season are 20% lower than at the same time last year, at least above 80N. Could all the snow on t3he ice be fooling the instruments?
TT you put too much confidence in that product.
I really like that JAXA thickness map, it indicates tendencies especially in the edge of the pack, where melt is happening etc, but see yourself the unrealistic fluctuations in the graph... maybe too sensitive to air temperature changes, snow, etc?
Said so, volume may not be far from last year's, there are other factors apart from FDDs
Laptev sea ice is thin because winds have been stripping ice off the sea surface continuously for two months, and new sea ice is formed immediately. The ice seems thin not because of the heat from beneath or above or anywhere, but because it is being reformed continuously. The stripped ice seems to be accumulating in the ESS. That is some creation of ice that the FDDs wont explain.
Ice in Barentsz sea is finally gaining some area (I thought it was gone for good) there you have more ice not following the formula.

46
Arctic sea ice / Re: The 2016/2017 freezing season
« on: February 18, 2017, 09:21:17 PM »
Using the reanalysis, we can calculate also the mean of the downward radiation flux...
So, what if we try with the precipitable water?
It looks way better...

I will not try an argument about chickens and eggs. It is of course difficult to disentangled all the mechanisms ongoing. But at least the increasing of water vapor, linked to warming of the temperatures but also to the decrease of Arctic sea ice, is increasing downward radiations.

The major point is that a warming of 20°C or 30°C is not impossible at surface is thus not impossible. With global warming, the "thin" -a 2 km thick and 20°C inversion is massive for an inversion in the absolute, but compared to the whole atmosphere this it is not so thick nor so cold- the "thin" layer of permanent inversion is set to be destroyed, with only marginal warming above. Usually there is around 5 to 10°C between surface and 850 hPa. Even a 7-8°C lapse rate with a 850 hPa layer around 250K would imply a mean surface temperature a bit below 260K, around -15°C, barely enough cold for sea ice.

Wow thanks for that piece of work! Isn't there something remotely similar published out there?
Pretty scary conclusions. 
This graph shows the warming of the Arctic layers :



The surface 1000 hPa is warming fast and is now warmer than the 850 hPa for the first time since 1981 (and probably since many millenniums...). And the strength of the inversion (or of the now non-inversion) taken as the difference between the 850 hPa and 1000 hPa temperatures :

Killer graph. That yellow line is showing almost 20 degC of warming!

47
Arctic sea ice / Re: The 2016/2017 freezing season
« on: February 18, 2017, 04:12:16 PM »
Another view of the debris left behind by the powerful storm that passed over Fram Strait a few days ago
The Fram situation is amazing and disturbing. What looked like good ice cover turned to an ice cube soup in a few days of battering, and this in February. Were it not for the MYI the whole thing could have become open water. I shudder to think what the summer might bring.
I totally agree, the more images I see of it, the more I think this was an incredible event. Not sure if somebody remember such a mess being done of so much MYI in a handful of days!
Not that this ice was not going to melt out soon anyway, but, I dont think this is going to help to keep MYI precisely now when Fram export typically is maximum

48
Arctic sea ice / Re: The 2016/2017 freezing season
« on: February 18, 2017, 02:20:30 PM »
Feb 13-18,  115 hour loop
Pretty good flow south through the Bering Strait.
Imagery courtesy of the University of Alaska at Fairbanks
 I05 band. Alaska at bottom center
There is an interesting feature in this animation, sort of a Lake Ness monster showing the head in Beaufort sea. There is like a river of water/ice just flowing near the Barrow coasts. Says a lot about how the ice state is in this part of Chukchi/Beaufort seas, recently formed and thin, that an underlying current of warmer water may by breaking through and showing up... at least temporarily.

49
Arctic sea ice / Re: Piomas vs. CryoSat
« on: February 18, 2017, 02:12:35 PM »
I've been able to look some more into this, with the help of Michael, who sent me the data that allowed me to create this graph:
...
Of all this, what amazes most is your eyeballing capabilities. Man, that you were able to detect this from the Cryosat maps with the colors they have ...

50
Arctic sea ice / Re: The 2016/2017 freezing season
« on: February 18, 2017, 01:27:39 PM »
Another view of the debris left behind by the powerful storm that passed over Fram Strait a few days ago (worldview Terra Brightness). https://goo.gl/G0TMbz
First frame is Jan 31 before the storm, then clouds do not allow clear images until Feb 13. Last five frames show transport of the MYI blocks from Feb 13 to Feb 17.
I agree this ice will be moved quite easily, the announced winds will push all this ice to the Atlantic Ocean.

A question to the experts, the fast ice that gets loose from the North Greenland coast (producing the darkest blocks close to the coast) is sea ice or product of glacier discharge?

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