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Messages - Pagophilus

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1
Arctic sea ice / Re: The 2019 melting season
« on: July 08, 2019, 03:28:45 AM »
Most of the southern ESS, from the coast to about 200 - 300km towards the pole, is now a mass of loose floes, in some places with significant open water.   And then a close-up.   Top image unaltered, bottom pushed for contrast on Photoshop.  It seems to be happening scarily fast.

Off (and off-line) to the mountains for a few weeks... back in Sept.  May the ice be with us...

2
Arctic sea ice / Re: The 2019 melting season
« on: July 06, 2019, 06:27:36 PM »
Those rhomboid shaped floes is where PIOMASS sees thick, MYI, some of the thickest ice left in the CAB.
Given the location of much of that thicker ice, and given the fact that there has been much clockwise rotation of the main pack towards the Atlantic, it would follow that ice has been piling up on the poleward side of these islands for some time.   

I therefore cannot help wondering whether the extra thickness on the poleward sides of these islands is at least partly caused by extensive ice ridging in these areas thickening the ice rather than by MYI somehow occurring in relative isolation in these three areas.

3
Arctic sea ice / Re: The 2019 melting season
« on: July 06, 2019, 02:22:33 AM »
Consider it fate, but Gerontocrat posted the daily extent losses for July 2012 on the data thread today. You'll see a couple of intervals of serious losses there as well.

Motivated by your graph, attached is NSIDC extent for July 4 2019 compared with Aug 4 2012.  It gives an idea of what would have to melt out for in the next month to keep pace with 2012.  It looks pretty feasible to me, but others have way more experience.

4
Arctic sea ice / Re: The 2019 melting season
« on: July 06, 2019, 01:51:00 AM »
The fast ice nearer the delta broke up extensively about a week ago (it disappeared long ago right next to the delta).  The ice now breaking up in the image was spotted by grixm yesterday.  Today, there are many more cracks in this area, which to me indicates ice that has passed a certain threshold of integrity and thinness.  Melting may be rapid from here.
Do you think we will be able to use the upcoming piomas data to get the threshold where sea ice breaks apart this season?

An interesting idea!  Maybe this would be done retrospectively first... where did ice break up in the past and what was Piomas 'saying' at that point?  Are there correlations with indicated Piomas thickness and time of fracturing?
   
But all in all, I would be hesitant, since Piomas is modeled, not measured, and its output has a general quality to it (as would be expected).  And I imagine so much probably depends on ice quality as well as thickness when it comes to ice breaking up.  And also, are we maybe talking about fast ice in your question, because much of the pack ice is already pretty rubbly already?  Having shot my mouth off (something of a problem I regret to say) I now step aside and let the experts take charge.

5
Arctic sea ice / Re: The 2019 melting season
« on: July 05, 2019, 11:23:29 PM »
July 8 Nullschool forecast, surface winds and temps.

Looking somewhat toasty for the ESS...

6
Arctic sea ice / Re: The 2019 melting season
« on: July 05, 2019, 11:18:58 PM »
Laptev fast ice breaking up with great rapidity in the region of the Lena Delta.

The fast ice nearer the delta broke up extensively about a week ago (it disappeared long ago right next to the delta).  The ice now breaking up in the image was spotted by grixm yesterday.  Today, there are many more cracks in this area, which to me indicates ice that has passed a certain threshold of integrity and thinness.  Melting may be rapid from here.

7
Arctic sea ice / Re: The 2019 melting seas
« on: July 03, 2019, 11:40:39 PM »
As far as forecast interpretation, Michael’s one was not that outlandish (it’s a tad cooler) and Friv stopped posting, which correlates well with the change of weather.
That as long as outlandish is not “out of what the tribe thinks”.

+1      As long as a poster can back up their ideas and predictions with reasonable evidence and logic, then in my view they should be allowed to post without personal harassment.  If you disagree with someone, then debating that is one of the ways that science progresses -- just make the argument, not the accusation.   

8
Arctic sea ice / Re: The 2019 melting season
« on: July 02, 2019, 06:42:26 PM »


Huge export of ice coming down into the Fram (I wonder how much of that is MYI).



Far less than in years past as there is far less MYI to export.

Good to have this experienced perspective.  It is also true, is it not, that the less MYI remains in the CAB, the more significant the loss of that remaining MYI becomes?

9
Arctic sea ice / Re: The 2019 melting season
« on: July 02, 2019, 05:57:43 PM »

Ice south of the Fram is still counted in extent, area and volume regardless of whether it has a shipping label on it or not.
True but I think people are looking forward to the immediate future when talking about dispersion and ice export. The life expectancy of ice depends on where it is ? It is reasonable to assume that in July open water created in the CAB, for example, by Fram export will not freeze over, while the ice sent down the Fram is doomed to die pdq.

This is a problem that comes up over and over in science and in almost any discussion.  I think much can be clarified by people first defining the system they are analyzing.  So, if we define the system/area we are discussing as the CAB, then it becomes clear that spreading of ice in the CAB can be said to be dispersion, and ice spreading out the CAB can be said to be export.

10
Arctic sea ice / Re: The 2019 melting season
« on: July 02, 2019, 03:36:00 PM »
Sea ice concentration, June 17 – July 1

Huge export of ice coming down into the Fram (I wonder how much of that is MYI).

ESS, Laptev, and Beaufort are lighting up.

CAA is continuing to dwindle away.
Thanks again for these vivid, useful animations.

Your emphasis on the Fram export is I think important.  That export is set to continue fairly strongly for the next three days, with winds driving export fading thereafter, but not reversing.  We only 'see' this Fram export on animations such as yours because the ice melts in the Greenland Sea about the same rate as it arrives.

One can almost sense the 'squeezing' of the main pack towards Greenland, and particularly the Fram area on your animation.  Perhaps subjective on my part

The continued disappearance of ice from the Kara and Chukchi, and the ever-wider yawning of the Laptev bite are also notable.  Will upcoming wind patterns send the ice a little more towards the Siberian side and close that yawn somewhat?


11
Arctic sea ice / Re: The 2019 melting season
« on: July 01, 2019, 03:03:02 AM »
Current forecast continues to be for improved conditions for ice retention.

Perhaps it is worth mentioning of the Atlantic margin of the ice, where the map you posted shows a generally strong positive temperature anomaly.
   
>>  3 day forecast is for winds that ensure sturdy export of ice through the Fram Strait. 
>>  Continued warm winds are forecast to keep entering the Kara Sea, which is rapidly becoming mostly open water. 
>>  The forecast winds will also favor the dispersal and therefore eventual melting of the ice tongues that extended into the Barentz.  These are becoming more attenuated already.




12
Arctic sea ice / Re: The 2019 melting season
« on: June 30, 2019, 06:57:47 AM »
No, the GAC did not compact the ice it MELTED it. The reason the dispersion curve dropped after the GAC is that dispersed ice was more prone to melting than ice piled up on the CAA.

The GAC was not a magic cyclone that violated the Coriolis effect, compacting dispersed ice.

Okay, then, that does seem a sounder explanation ... but it was a beautiful grenade.  And Gerontocrat's extent over area graph could be useful now, considering that 2019 is in 2nd place for the date... thus indicating high dispersion of ice and therefore higher vulnerablilty to melting.  It will be interesting to see how this ratio develops over the next few weeks. 

13
Arctic sea ice / Re: The 2019 melting season
« on: June 29, 2019, 04:48:41 PM »
Can't you just say humanity? I am offended by women exclusion, they're as bad as men.
No, maybe that should be hupersonity to be nonsexist.
No, wait, huperdaughterity?

Can we stop here?  I know it's "just joking around", but intentionally or not, this interchange is acquiring a tone that is mocking of the efforts of women (and men) to produce a world with more equality.  It also communicates a sense that this is forum where men dominate and women must accept their 'second place'.  We should avoid this.  Can we get back to the science? 

14
Arctic sea ice / Re: The 2019 melting season
« on: June 28, 2019, 06:00:05 PM »
...
With a 1,000 miles of continuous 20knot winds blow through the strait, some of that warmth is moving east and then toward the ESS after it hits the Arctic.

How does it impact the ice in the near term? I'm not sure. The Bering Strait is pretty shallow so the heat may dissipate quickly when mixing with deeper water. There's also the possibility that the remainder of the coastal ice in the ESS will blink out pretty quickly.

Something to keep an eye on.
Actually there's another branch of surface  flow from the Bering Sea that feeds the Alaskan Coastal Current and mixes with Beaufort waters...

Woods Hole Oceanus article https://www.whoi.edu/oceanus/feature/a-ticking-time-bomb-in-the-arctic/  addresses a directly related issue: the warming of the Chuckchi sea via insolation, which must have been even more extreme this year given how early ice was lost there.  This issue is described as a 'ticking time bomb' by John Toole, a scientist at Woods Hole.   

The forecast weather event you describe will be layered on top of this.   

15
Arctic sea ice / Re: The 2019 melting season
« on: June 28, 2019, 03:20:29 PM »
Some general global context for all that we see happening now in the Arctic, from NOAA
https://www.ncdc.noaa.gov/sotc/global/201905

"This was the second warmest March–May period for the global land and ocean surfaces in the 140-year record at 0.96°C (1.73°F) above the 20th century average and 0.15°C (0.27°F) less than the record set in 2016 (+1.11°C / +2.00°F)."

"Global land and ocean surface temperatures during the March–May period were warmer than average across much of the world's land and ocean surfaces. The most notable warm temperature departures from average were present across much of the high latitudes in the Northern Hemisphere, specifically across much of Alaska, northwestern Canada, and north-central and Far East Russia. The temperature departures from average in these locations were at least +3.0°C (+5.4°F)."

The NOAA June report is of course not out yet.

16
Arctic sea ice / Re: The 2019 melting season
« on: June 28, 2019, 02:06:58 AM »
ESS and Laptev, June 20-27

Click to animate.

The ESS was blue with meltponding before this, then it went dull gray and began to crumble.  Looks like the Laptev may be following, currently entering the dull gray stage...

17
Arctic sea ice / Re: The 2019 melting season
« on: June 28, 2019, 12:57:10 AM »

there won't be ice in hudson by then.

what would that take away from the 2nd place prediction ?

The Slater prediction has its value, but the Slater map, in my view, is pretty strange.  I would not base any specific interpretations upon it.

I covered this in Reply 1487 in significantly more detail but the Slater map is a map of the current conditions and does not depict the extent predicted.

Thanks for the clarification.  I know a lot of people respect the Slater prediction, so I will certainly respect that.  But given the confusion the Slater map causes, I have to wonder why they publish it all.  It is, as you state in Reply 1487 really just a differently colored version of the current NSIDC concentration map (they should state that this is the case, BTW).  The map only puzzles people who see it (Magna this year, myself last year), at least in this context.  And it made me mistrust what by all accounts is a pretty good predictive tool.   

18
Arctic sea ice / Re: The 2019 melting season
« on: June 27, 2019, 03:31:17 PM »
June 22-26.

Thanks again, Aluminium.  NSIDC extent comparison map showing changes over the last two weeks shown below to add to your animation.

Most notable to me on the NSIDC image, apart from the expected general peripheral ice loss, are the large declines in extent in Hudson Bay and in the Kara Sea.

Much of the Kara Sea loss is attributable to the low that has persistently centered over Novya Zemlya (X, bottom image) for much of the past week, scooping ice out of the Kara (arrow).  There has been melting too, of course.  This low is forecast to disperse after June 28.

Extent (not new ice !!!) has grown in the Beaufort through dispersion as the main pack has squeezed towards the Canadian side.  And the two tongues of ice in the Barentz, again produced by dispersion, remain stubbornly in place, melting out slowly, I believe, because the Barentz sea surface has been cooled by all the ice extruded into it this spring and summer.  How much longer can they persist?   

'Growth' of extent in the Laptev is due, I think, to extensive melt ponding in the Laptev two weeks ago fooling the AMSR2 instrument into showing open ocean there.

19
Arctic sea ice / Re: The 2019 melting season
« on: June 27, 2019, 05:08:51 AM »
Wow

My guesses for 9/1 and 9/20

You can see how all the FYI is about to blink out in everything peripheral to the CAB. The rogue chunks of second year ice in between stand no chance at survival once that occurs.

The areas that appear to be ready to disappear very quickly expanded dramatically yday. A comparison with 2012 shows similarly-shaded bits of ice that year were prone to melt and dispersal within the following 30-45 days.

We must consider that 2012's GAC may have also been the RESULT of so much ice melting at once. The melting of ice gives off tremendous energy. Maybe it would have happened anyways but maybe it occurred precisely because the year was so bad. We have seen GAC-y events in years since as well, earlier and earlier in the summer.

So, we shall see what 2019 holds, but if momentum is any indicator I see no reason why we don't follow in 2012's footsteps with a GAC event, but this year it will probably be earlier in the season due to the greater insolation already absorbed across much of the Arctic Basin.

I am puzzled by these statements.  The melting of ice is an endothermic process. 

20
Arctic sea ice / Re: The 2019 melting season
« on: June 26, 2019, 03:24:50 PM »
The Arctic does tend to surprise us, as for me perhaps the biggest realisation has been how resilient the ice really is. Everything seems to be heading to total oblivion every year, but hey, then it just ends up more or less the same as last year.

But looking at the bigger picture, on average in the 2010s, about 2/3 of the annual max melts out, in other words, the annual melt is double the residual. In the 1980s it was closer to par, slightly more than half the annual maximum melted out.

The decadal average is falling by 1 million km2 each decade, so that gives us 40 years to reach 0 average extent.

To me these numbers imply that the ice is not likely to melt out this year, and that reaching a new record is going to be very difficult (average is 4,4 this decade, the record is 3,2) but reaching second place not so very difficult (4,1) and third place is really just average melt for this decade.
But the 40 year extrapolation  assumes that the melt will proceed in a linear fashion as we get closer to 0 extent.
Many predict that as the ice reduces, positive feedbacks such as lower albedo of open water compared to ice, easier export of less rigid ice masses  and changes to the jet stream mean that ice loss could accelerate and reach a tipping point which could mean 0 ice much sooner.

Agreed.  These feedbacks could easily accelerate. 

In addition, the monster threat of potential changes in Arctic surface ocean temperature (as warm salty waters pour in and threaten the thin, cold, freshwater 'lid') already has its foot in the door, and is itching to make its full entrance and melt the Arctic ice from below.  The more ice is lost in this way, the more exposed the surface waters to wind mixing of these two layers.  Then more ice is lost etc, making this is another positive feedback, potentially a gigantic one. Sometimes, with the focus on atmospheric phenomena, this factor is left backstage.

So, with that 40 year extrapolation... I see why it is made, and I can only hope that it is correct.  Like you, I have little confidence that it is.

21
Arctic sea ice / Re: The 2019 melting season
« on: June 26, 2019, 02:27:08 PM »
Focussing on "the numbers", as you put it, is an example of the streetlight effect. Area and extent are useful in sometimes indicating anomalous regions, regions where one might want to try to figure out what's happening, but nothing more. (Obviously just my opinion.)

Really it just comes down to the weather now.

Area and extent are imperfect indicators, but at least can be directly and fairly reliably measured, unlike, say, volume. Area and extent numbers and maps from the various outfits that produce them (NOAA, uni Bremen, Jaxa ...) stay in general agreement while what volume maps exist are much more idiosyncratic.

Changes in area and extent have to be read in context - time of year, weather conditions, the quantitative(eg thickness) and qualitative(eg solid pack or loose rubble, rottenness) state of the ice. JAXA flatlined because of ice export and dispersion from June12-16 (losing only 40000km2 of extent in that period) while the weather was terrible for ice and volume was clearly taking a hammering - all those deep blue meltponds, and the huge amount of wet ice that appeared around then.

These are subjective and complex judgements to make for anyone. Its easy to get (maybe over)excited by some event. especially for us interested newbies with only a few or less seasons under our belt.

+1

22
Arctic sea ice / Re: The 2019 melting season
« on: June 25, 2019, 01:29:52 AM »
Focussing on "the numbers", as you put it, is an example of the streetlight effect. Area and extent are useful in sometimes indicating anomalous regions, regions where one might want to try to figure out what's happening, but nothing more. (Obviously just my opinion.)

Really it just comes down to the weather now.

How ironic then, that the minimum will be defined in terms of area and/or extent. 

I think that we would both agree that the overall decadal decline in the ice is due to the massive forces of climate change.  Beyond that, however, variations in the behavior of the ice usually come largely down to the weather, so I believe your last comment always applies, Jan to Dec.

To me, the weather, the ice, the ocean currents etc are the phenomena being observed, and it is through measurement that we can quantify what is going on.  I fully agree that extent and area measurements have their limitations, especially at this point in the season.  And we should never put too much store by short term bobbles in data sets.  But, to me, that does not mean area and extent are not a vital part of the picture that I continually try to grasp, aided by you and others on this forum.  Without area and extent measurements I would be left floating more than ever in a sea of assumptions -- so to me, while they can be used effectively as 'streetlights', they also produce a diffused, year-long glow that helps illuminate, and even define, the bigger Arctic picture.   :)

23
Arctic sea ice / Re: The 2019 melting season
« on: June 25, 2019, 12:25:32 AM »

This. Some ice cliffs simply don't show up in the present headline extent number, but they do affect the ice itself. The effect will be felt in the coming weeks until September. This is why I find Gerontocrat's claim of unjustified hyperbole in the melting thread to be unsubstantiated. Bad for the ice doesn't mean inmediate extent and area drops - this can only happen in regions where all or some of the ice is already thin. But in the ESS (for example) ice is quite thick, and to melt it to near-zero area by September requires major melting in June-July that barely affects area, if at all.

I suspect we are all on the same boat, really, thinking that a very low minimum is likely, and that a record low is possible.  That is the case every year now, it seems.  Maybe a record minimum is more possible this melting season with each passing day -- I am certainly worried.  But my understanding of critiquing hyperbole is that imminent weather events are sometimes presented here as the events that are going to take down the Arctic ice, either by direct statement or by implication, and I took Gerontocrat's comments to mean that.  There is, as he reminds us sagely, still a long way to go with the melting.  Gerontocrat is going by the numbers, present and past, and I like very much that somebody does so regularly and reasonably, as it helps keeps me grounded. 

24
Arctic sea ice / Re: The 2019 melting season
« on: June 24, 2019, 06:26:10 PM »
I don't think the melt in the central Arctic around June 17 is from heat from wildfires... that is too small an amount of energy, I believe.  It is more the smoke that makes the difference to the ice.  But on the last frame, June 24, we do seem to see the effects of the ridge that has pulled a huge amount of heat into the central Arctic...

I see! So the rapid movements of red that seem to sheer through are really the smoke from the fires being carried by the winds, correct? And the red that's closer to the shoreline is heat moving in from the actual fires themselves? I know it's not exactly scientific, just making sure I understand what's happening from a layman's point.

I don't know if the 'rapid movements of red' are artefacts from the smoke from the fires, but I suppose they could be. I am not sure even what the instrument producing that red pattern is actually measuring.  I think the red color might be a reflection of the surface condition of the ice (surface water?), as per SMOS imagery but I do not know.   Way above my pay grade here so I leave that to others. 

It is just my strong intuitive sense that the wildfires burning at present form only a small proportion of the total heat coming from the vast expanses of a very warm Siberia and beyond.  Much of Siberia, and the Siberian side of the Arctic ice have been baking in near continuous sunshine for 24 hours a day (or for very long days further south) for two weeks now.   That is an incredible amount of solar energy.  All that said, I myself would really like to learn the answer to your questions.

25
Arctic sea ice / Re: The 2019 melting season
« on: June 24, 2019, 05:42:39 PM »
Sea Ice Concentration, June 9 – June 23 (click to animate)

Look at the melt in the Fram in the last two days!!

Beaufort still seeing significant melting; also looks like more ice is being pushed in from the east.

Laptev melt extending further south.

Kara was holding up better than the others but the melt has started to kick off.

Check out the melt in the central arctic around June 17. I assume this is heat from the Siberian wildfires?

Ice has significantly degraded in Baffin.

Hudson and CAA are melting fast, too.
Thank you, cavitycreep.  Great animation.  Please keep them coming.  A couple of comments.

I agree melt in the South Kara Sea is proceeding apace... ice is very thin there (see above).  Not sure about the north Kara though, although the very blue patch of fast ice there supports your statement.

"Beaufort still seeing significant melting; also looks like more ice is being pushed in from the east." Agree on this, and this is what Michael H. got such heat from some for suggesting a few days ago.

I don't think the melt in the central Arctic around June 17 is from heat from wildfires... that is too small an amount of energy, I believe.  It is more the smoke that makes the difference to the ice.  But on the last frame, June 24, we do seem to see the effects of the ridge that has pulled a huge amount of heat into the central Arctic...

26
Arctic sea ice / Re: The 2019 melting season
« on: June 24, 2019, 05:17:08 PM »
The fast ice next to Kara Lena delta breaking up over the past week.  A considerable area... more than 300km long, up to 50km wide in north, up to 100km wide in south (coastal end).

b_lumenkraft, you have changed my life.  God bless you, sir, and thank you for your clear instructions earlier on how to make a gif.

Click to animate...


27
Arctic sea ice / Re: The 2019 melting season
« on: June 24, 2019, 04:05:03 PM »
Arctic wide sea ice area is now lowest for the date in the high resolution AMSR2 record:

http://GreatWhiteCon.info/2019/06/facts-about-the-arctic-in-june-2019/#Jun-23

And if you exclude the peripheral seas the picture is much more stark:

And, as many have mentioned, the distribution of the ice this year is significantly different to previous years, as these NSIDC comparison maps show (comparisons for the June 22 date between 2019 and 2018, 2016 (near record) and 2012.  So there is soooo much uncertainty ahead.

BTW I find these maps to really help with visualizing what is happening to the ice, especially this season and how unusual the situation is.  The comparison tool is really quick and easy to use. 

With the Pacific side so open, and ice pouring into the Atlantic, much may depend on how quickly the rather stubborn ice distribution on the Atlantic side changes in the coming weeks.

Thank you, developers at NSIDC !   http://nsidc.org/arcticseaicenews/sea-ice-comparison-tool/   

28
Arctic sea ice / Re: The 2019 melting season
« on: June 24, 2019, 06:47:55 AM »
The ongoing, rapid collapse and fragmentation of the ESS fast ice continues...

I'm guessing many of you have seen this before, but it is mind-bending for me to imagine the scale and speed of this as I sit at my computer...

29
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: June 24, 2019, 06:33:02 AM »

Pragma, thank you.  But all the credit has to go to the NSIDC, they can be obtained here:

http://nsidc.org/arcticseaicenews/sea-ice-comparison-tool/

I think they are amazing too, and I am glad to bring them before this forum if they have not previously around.

LOL! I'm laughing and embarrassed. As I have mentioned before, NSIDC is updating their tools all the time and are very receptive to suggestions.

I was going to email them, suggesting a comparison tool.  :-[

Um, er ... never mind  :)

Not at all -- it was a completely natural mistake -- although if you knew how limited my programming skills are you would not have made it.   I myself just stumbled upon these comparison maps.  I had never seen anyone use them here, so I felt like someone pulling out a clamshell phone at an Apple convention, until you kindly responded. 

30
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: June 24, 2019, 12:38:12 AM »
JAXA ARCTIC EXTENT :-  9,728,067 km2(June 22, 2019)

- Extent is 5th lowest in the satellite record.
- Extent loss on this day 87 k, 13 k more than the average loss on this day of 74 k.
- Extent loss from maximum 4,543 k, 156 k (3.6 %) greater than the average of 4,387 k loss from maximum by this day,
- On average 44.4% of the melting season done, with 83 days to average date of minimum (13 September).

We are now entering the period of maximum daily extent loss that lasts until mid or late July.
Until the last 2 days, over the last 2 weeks and more extent loss has been below or well below average.

Will above average daily extent loss be sustained?
Will area loss follow suit and return to at least average daily loss levels?

Like many another, I have been wondering why extent losses have dropped so slowly.  I think much of the reason may lie in the Barentz Sea.  Two tongues of ice have been projecting into the Barentz for some time, as the ice pack rotated away from the Pacific side and towards the Atlantic side, an unusual move.  One tongue projects between Svalbard and FJL and one between FJL and SZ.

The initial reaction was that this ice had gone to 'oblivion', into the 'killing zone', and I too was of that opinion.  In fact the ice tongues have been remarkably persistent (see the first comparative NSIDC map below, comparing June 8 and 22 this year).  No doubt this is partly because new ice is entering the Barentz, but the Barentz waters are cooler this year, and I think this may be in large part because so much ice has melted into the Barentz, forming a cold freshwater layer at the top, at least in the region of the ice.  So there ice hangs around longer than expected in the Barentz, so extent declines more slowly (the Beaufort also plays its role, but others have mentioned that).

Comparisons with June 22, 2018 (second map) and with the silver-medal-holding 2016 show how unusual this situation is.  There is a LOT of ice in the Barentz.  Will the main ice pack melt as far back as in previous years, to the continental shelf to the N of FJL etc?  That might be a big determinant as to how low extent goes this year.   

31
Arctic sea ice / Re: Arctic Image of the Day
« on: June 22, 2019, 09:09:06 PM »
An uncanny cloud face appears in the South Kara Sea in this still from a Colorado State University animation.

Facing to our left, three quarter view.  It was almost shocking to see it pop up.  May be embracing a lesser deity.


BTW, this program produces terrific animations of current weather patterns, I was alerted to it by JayW on the melting thread. 

http://rammb-slider.cira.colostate.edu/?sat=jpss&z=1&im=24&ts=1&st=0&et=0&speed=130&motion=loop&map=1&lat=0&opacity%5B0%5D=1&hidden%5B0%5D=0&pause=0&slider=-1&hide_controls=1&mouse_draw=0&follow_feature=0&follow_hide=0&s=rammb-slider&sec=northern_hemisphere&p%5B0%5D=band_m08&x=13964.5&y=16288

32
Arctic sea ice / Re: The 2019 melting season
« on: June 22, 2019, 04:30:06 PM »
In the light of all the recent weather predictions, for my own purposes I have to make sense of what actually happens as those predictions unfold.  So forgive me if the following seems redundant to some of you... it may not to seem so to less experienced people like myself. Lots of lacunae in my knowledge, happy to be corrected.

Images are from Worldview, unaltered.
1.  The low pressure system remains parked over Novya Zemlya and is forecast to continue to do so.  Ice will continue, presumably, to get dragged in an arc out of the Kara and towards the Barentz.
2.  For fun.  The bluest ice I can remember seeing on Worldview, fast ice in the northern Kara coast. Closeup below the first image.  I am guessing the ice here is melting like crazy and forming massive meltponds in the process.
3.  I presume this is the warm, humid ridge being drawn from Siberia by the joint action of the low on the right of picture and high on the left of picture.  Should be interesting to see how it develops and what it does.  If the clouds are telling the story, it looks like it is just in the process of forming over the Arctic ice.
4. High pressure area.  Lots of solar insolation over this summer solstice.

33
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: June 22, 2019, 03:24:13 PM »
It is unusual for area and extent data to persistently (i.e. more than two weeks) to go in one direction while weather models and other data point in another direction.

Hence the comment " mixed messages".

It is reasonable, to remark when statements in in other threads , e.g. "Panzer divisions" (not my phrase) fail to mobilise and Friv's extravagant forecasts do not materialise in or seem justified by changes in the area and extent data so far. "Looks like it's going to [be] pretty soon that sailing from Pacific to Atlantic w/o an ice breaker. Perhaps June."(NOT one of Frivs)  is a candidate for the future.


Gerontocrat, I read your editorial comments as extremely useful and sensible.  You base them on the current evidence from the Arctic and the past behavior of the ice.  That is what a scientist does.  I don't just like your comments, I need them.  You are anchoring so much of the discussion on this forum. 

On the melting thread, which is a lot of fun, speculations dart all over the place and they are sometimes rather detached from the overall data.  The discussions often resemble those that scientists have after they have had a few beers.  I sometimes get a bit intoxicated myself.  One day an apocalyptical prediction is going to come true, we all know that, but meanwhile I prefer to think like a Casino owner, mostly going with the behavior of the overall system, not the individual bets.  So, please, please continue to make your comments. 

BTW   I agree that discussion of your comments (as opposed to questions about data) should go to other threads.  However, I don't think you need to defend them.  We know who you are, and you are doing more than enough already.   

Over and out.

34
Arctic sea ice / Re: The 2019 melting season
« on: June 22, 2019, 02:35:36 PM »
Fires south of the Laptev Sea are growing, and the high will draw smoke north over the next couple of days.

I've attached a gif (click to animate)of june 19 and 21(20th obscured by cloud) showing the northernmost fires, quite small on the 19th, but now producing a huge pall of smoke or smog. And the Copernicus/WindyTV PM2.5 particle forecast for tomorrow, which I'll assume is a proxy for smoke in the far north

Thank you for the animation. I would like to be clearer in my own mind as to what these fires mean for the ice.  My interpretation is that if the smoke drifts over the Arctic, then the smoke acts rather like clouds and shields the ice from solar radiation.  But if there is rain or snow or something else that brings the soot from the fires onto the ice, then that darkens the ice and top melting might then proceed more rapidly.  So a lot depends on whether the smoke stays aloft or settles  Am I missing something? 

If I have it right, then in these sunny conditions, then it would seem reasonable to assume that this smoke over the Laptev is helping preserve the ice.  Happy to be corrected!

35
Arctic sea ice / Re: The 2019 melting season
« on: June 21, 2019, 03:06:24 PM »
The much-heralded low pressure system, centered just S ('above') of the center of Novya Zemlya earlier today. 

I hope it doesn't hang around there, because it is perfectly positioned to scoop ice in an arc out of the Kara Sea and into the Barentz.  (Later edit: Nullschool has the low parked here for about 4 more days - ouch)  I believe the warm ridge can be discerned as a bank of cloud on the left of the image.

IceShieldz, the low is not nearly as cloudy as I expected it to be... I am already getting schooled by the Arctic.     

Worldview image, contrast tweaked on Photoshop to help differentiate ice from cloud.

36
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: June 20, 2019, 11:46:19 PM »

Quite a lot of hyperbole on the melting season thread on expected sea ice collapse not yet showing in the data NSIDC and AMSR2 data.


Perhaps a graph showing the number of hyperbolic predictions written per day on the melting season thread would be useful?  That would allow comparison with the NSIDC and AMSR2 data and we could see whether there was any correlation or not.   :)

37
Arctic sea ice / Re: The 2019 melting season
« on: June 20, 2019, 09:14:33 PM »
Just for the record, I was asking a question, not making a point.  Pedantry would imply I was imparting knowledge.  I was seeking it.

Indeed, I am the one being pedantic  :)

Just for the record, I was asking a question, not making a point.  Pedantry would imply I was imparting knowledge.  I was seeking it.   Later edit below

My apologies, aperson.  Because of the general tone of some recent posts, I was disposed to taking your remark as being personal to me, and I wrote hastily.  As I reread your message I now see that was not the case at all, and that you are simply providing expert knowledge, which was what I was asking for, so THANK YOU!   

38
Arctic sea ice / Re: The 2019 melting season
« on: June 18, 2019, 11:28:20 PM »
SMOS_beige_pixels.png]a record low dry ice area[/url] for 16 June.

Wow.   Hardly a dry ice in the house.       ;)

(Thanks for the link and explanation to SMOS)

39
Arctic sea ice / Re: The 2019 melting season
« on: June 17, 2019, 05:44:41 PM »
Sea Ice Concentration, June 2 – June 16 (click to animate)

Thank you -- a terrific animation.  The colors of low concentration ice make it particularly vivid.  In particular, for me, it shows:

--- The "bellying-out" out of the ice in the Beaufort, and the two tongues of ice spreading into the Barents Sea over the past few days... Those visuals go a long way to explaining the growing extent of ice on some days even while area has declined steeply.

---  The rapid export of ice through the Fram and the even more frantic squirting of ice through the Nares Strait.

And man, that Baffin Bay ice looks as though it is shrinking very rapidly...

40
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: June 15, 2019, 10:13:40 PM »
For me, the image below illustrates another possible way extent might get greater while the ice is really melting like crazy.  (Remembering that extent includes any target area that contains at least 15% ice):

Large skeins and tendrils of disintegrating, melting ice extend from the main area of the floes and out into the ocean in this image.  You see these repeatedly at the edge of floe fields when melting is occurring.  If these skeins comprise greater than 15% ice (and visually they certainly seem to) then this might well result in a microwave measurement of greater extent, even while melting is proceeding apace.  If this happens all the way along an ice floe front, as it is now for this ice field, the numbers can add up.

The image is from Worldview from today from the ice that has exited the Fram Strait, and now lies on the east coast of Greenland.  This ice is now in direct sunshine and is also subject to warm winds and is taking a tremendous beating.

I am not suggesting this is the whole story (there is obviously much more) but this could be a factor in producing results that show greater extent even while it is logical to think the ice is melting rapidly.

41
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: June 15, 2019, 06:54:30 PM »
Despite the headline extent numbers being what they are, anyone who becomes complacent at this stage is not looking at the whole picture. Look at the ice that is supposed to survive the melting season, the one in the inner basin. Look at its current area.

In fact, anything but complacency is warranted, if you take the current area and extent changes at face value.  Area is dropping, which most probably indicates less ice is present.  Extent is growing, which means that ice is being more widely distributed through the seas.  It follows that this spreading ice is more likely to melt out even faster in the coming days and weeks (as the distributed floes come in contact with waters that have not been precooled by the melting of adjacent floes.) 

So this gain in extent, if it is real, is a warning sign for the future, and an ominous one.

42
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: June 14, 2019, 02:44:22 PM »
JAXA ARCTIC EXTENT :- 10,207,081 km2(June 13, 2019)

Daily extent loss has been below average for the last 10 days.
An increase in extent in June is rare, and none anywhere near as much as 15k has happened this century.

Over the past three days or so, AMSR2 Bremen images have been showing open water in the Laptev where Worldview clearly shows fast ice (very blue fast ice).  It is a considerable surface area.  I love AMSR2 with all my heart, but it can be fooled during the melting season if surface water appears on top of the ice, and it seems pretty certain this is the case here (Worldview optical images are hard to contradict). 

So why the sudden, weird gain in extent?  A rapid flash refreezing of this thin layer of surface water on the fast ice (which might occur simply if temps drop overnight below freezing and AMSR2 happens to make its pass over the Arctic then) would then make it look like there was suddenly a lot more ice on AMSR2.  Recent minimum temps in parts of the Laptev have been listed as below freezing on the Climate Reanalyzer model so a brief refreeze is at least possible.  I am not saying I know this is what happened, and I am certainly not saying you don't have a LOT more knowledge than me (bows humbly in presence of the master), but I would like to put forward this as a reason for the rather unexpected recent gain in extent.

43
Arctic sea ice / Re: The 2019 melting season
« on: June 13, 2019, 08:28:56 PM »
..... and the warmest part of the Arctic Ocean in the next three days is going to be... The ESS ! 

At least according to Climate Reanalyzer (3 day, 2m temp forecast).   The ESS is the only widespread area in the Arctic Ocean that is projected to have both min and max temperatures over freezing.  And the ESS looks set to receive near constant sunshine. 

BTW, can we post more absolute temperature maps alongside the temperature anomaly maps.  Absolute temp maps may look less dramatic, but they do let observers know if temperatures are actually above freezing or not. 

44
Arctic sea ice / Re: Arctic Image of the Day
« on: June 13, 2019, 08:04:17 PM »
A frantic baby elephant makes a dash for the Bering Strait.

Climate Change is scary, and no white elephant.

Okay, I will stop now...

Worldview June 12, 2019.

45
Arctic sea ice / Re: The 2019 melting season
« on: June 13, 2019, 03:21:08 PM »
June 8-12.

The Laptev and the East Siberian seas have really extreme conditions for ice.

2018. Year ago I made first gif. Today it's possible to compare.

Thanks all for post interesting information about ice and weather.

Congrats on this anniversary.  I find your gifs very helpful for visualizing the ice, and with year on year comparisons now even more so.  The gifs that keep on gifing !

46
Arctic sea ice / Re: The 2019 melting season
« on: June 12, 2019, 01:30:38 AM »
Smoke from fires in central Siberia headed directly towards the Laptev, today on Worldview.  There is a distinct possibility these fires could get larger in the coming days, given the hot and sunny conditions.  I know this happens every year, but these seem to me to be the first large smoke plumes this year.

What will be the net effect on the ice?  Will the smoke tend to cool the ice beneath it by reflecting radiation back into space, or will soot from the snow settle on the ice, darkening it and accelerating melting?  Not rhetorical questions... I would like to know.  Does it depend on whether rain/snow takes the soot out of the atmosphere and deposits the soot on the ice?

47
Arctic sea ice / Re: The 2018 melting season
« on: July 08, 2018, 04:31:46 AM »
I'm no saint, no prude and no stranger to vulgarities, but I can say definitively that I believe this sort of language and 'humor' has zero place in any scientific discussion.  Furthermore, I can see this sort of thing as being particularly distasteful to women, or to persons who have been victims of sexual assault or those who have loved ones who have suffered such assault. 

It doesn't matter if some people say "Oh, it's alright with me" -- all members of the forum need to be considered.  Nor is the intent relevant, nor I am interested in castigating who wrote it -- it is the presence of such language, used in this manner.  Neven, I respectfully request that you draw the line here. 


I think he meant ANALysis.

As in, ANALrapist.


48
Arctic sea ice / Re: The 2018 melting season
« on: July 06, 2018, 12:17:58 AM »
Thanks for your highly cogent, informative post.   Do you see ongoing 'Atlantification' as contributing towards that meltout on the Siberian side?

We're likely to see a big melt out on the Siberian side with all the warm air advection, but the Canadian cold and Arctic ocean storms will lead to a good year for ice preservation on the Canadian side of the pole.

http://bulletin.mercator-ocean.fr/en/permalink/PSY4/animation/3/20170228/20180714/2/2

49
Arctic sea ice / Re: Arctic Image of the Day
« on: July 05, 2018, 09:54:13 PM »
Those are clouds formed from Lee Waves

Thanks.  I looked them up.  Fascinating!  Like air in a wind instrument, only gravity-assisted.

50
Arctic sea ice / Re: 2018 sea ice area and extent data
« on: July 05, 2018, 05:46:15 AM »
I expect July melt to catch up some of the ground (un)lost in June, including some century breaks, due to losses in the periphery.

In support of that, the South Kara Sea ice (below, unaltered image) is looking particularly dark and gray these days, and the Hudson ice seems a similar shade.  So albedo is getting lower, and both are currently receiving a good deal of insolation.

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