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Messages - JayW

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1
Arctic sea ice / Re: The 2019 melting season
« on: June 24, 2019, 02:59:53 PM »
The landfast ice in the ESS is simply vanishing - the GIF shows ice one day, gone the next. Look closely at the two last frames, large areas of ice simply disappear, but at the same time, the entire field starts shifting to the right and tearing like tissue paper.

Edit: The image is approximately 200km on each side, or 40.000 kilometres squared as the dude likes to say,  even three or four times in each posting, although always with the same spelling mistake.

2
Arctic sea ice / Re: The 2019 melting season
« on: June 23, 2019, 02:06:25 PM »
This location (arrow pic) in a Sentinel animation (GIF, click to play, 14, 18, 22.06) and the flow of warm waters (pic 2)

3
Arctic sea ice / Re: The 2019 melting season
« on: June 23, 2019, 01:21:25 PM »
Jeez, these SSTs! Also there is currently a pulse of Bering inflow as evidenced by the wonderful observations of JayW here:
https://forum.arctic-sea-ice.net/index.php/topic,2649.msg207094.html#msg207094

4
Arctic sea ice / Re: Arctic Image of the Day
« on: June 22, 2019, 09:55:41 PM »
Melting snowman agrees! Uncanny...

5
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

6
Arctic sea ice / Re: Arctic Image of the Day
« on: June 21, 2019, 05:39:09 PM »
The Freya glacier (Greenland) webcam is online again. Snow cover looks very bad compared to previous years.

https://www.foto-webcam.eu/webcam/freya1/

Really nice webcam images - I like the temp info as well - hits 11.9C on the 16th.  Noticeable that there are lots of blue-sky days as well.

Made an animated gif for the last 30 days:

7
Greenland and Arctic Circle / Re: The Nares Strait thread
« on: June 20, 2019, 09:19:36 PM »
Export from Lincoln Sea to Nares Strait has started up again.  GIF uses DMI Sentinel images from June 17, 19 and 20.

Viewing images at the DMI site down Nares Strait: Hall Basin got the memo and is filling up with ice from the north, but Kane Basin has a gyre recycling its few floes (for now).

8
Arctic sea ice / Re: The 2019 melting season
« on: June 20, 2019, 12:16:59 PM »
I found a paper that I thought is relevant to the discussion here:

Increases in the Pacific inflow to the Arctic from 1990 to 2015, and insights into seasonal trends and driving mechanisms from year-round Bering Strait mooring data

http://psc.apl.washington.edu/HLD/Bstrait/BStraitSeasonalInterannualChange2017/Woodgate2017BeringStraitChanges_28ththJune2017_TextTablesFigureswithfc.pdf

I haven't had time to read the whole thing, but it suggests that the average annual heat flux through the Bering Strait has increased as follows:

1991-2015: 7.2 ± 4.5 1018J/yr (after correction: 5.9± 4.6)
1998-2015: 8.7 ± 5.7 1018J/yr (after correction: 6.9 ± 5.9)
2000-2015: 9.7 ± 6.5 1018J/yr (after correction: 7.8 ±6.80)

It also cites Serreze et al, which I believe has been mentioned on here various times before:

Moreover,  a  recent  study  of  in  situ,  satellite  and  modeling  results  [Serreze  et  al., 2016] conclude the oceanic heat flux through the strait (in April-June) may explain 68% of the variance in the timing of sea-ice retreat in the Chukchi Sea, with model correlations suggesting the Bering Strait heat  flux  is  a  more  efficient  predictor  than  the  atmospheric  forcing  terms  of  wind,  surface  airtemperature,  or  radiation.

Bearing in mind the unprecedented (I believe) heat not just in the Chukchi Sea but also in the Bering Sea, this could be particularly significant this year.

9
Arctic sea ice / Re: The 2019 melting season
« on: June 20, 2019, 09:49:04 AM »
Ice that enters the Beaufort is as doomed as that leaving the Fram, but it will take until August.

It can be noted again that despite cold, cyclonic conditions over Beaufort and archipelago, min temperatures remains near -1°C and max temperatures near 2 -3 °C, SST remains warm for the region (2 - 3°C) and are note cooling, dew point are not strongly negative and soundings don't show temperature inversion. Beaufort sea is now a graveyard for ice. Open too early, warm too much during Spring.

10
The Central Arctic Basin (CAB) made a great leap forward in melting. The total of the Inner Basin as defined by Wipneus (CAB+Beaufort+Chukchi+ESS+Laptev+Kara) is showing a similar behavior, and is threatening to reach a record low.
The CAA, a typical holdout of thick ice, is far from a record low but keeping up the melting.
The Greenland Sea is being fed by all the missing volume in the Inner Basin, keeping up volume at a time of year when it should be dropping.

11
Arctic sea ice / Re: The 2019 melting season
« on: June 20, 2019, 09:31:21 AM »
East Siberia.

Looks like the fast ice cracked here from the weight of the inland freshwater sitting on it.

12
Arctic sea ice / Re: The 2019 melting season
« on: June 20, 2019, 09:25:42 AM »
That fast ice in ESS finally showing some cracks - bigg difference in one day. Click to animate.

13
Arctic sea ice / Re: The 2019 melting season
« on: June 20, 2019, 09:23:19 AM »

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.
LOL don't you see the ice being transported West from the CAB into the Beaufort in that recent GIF from Unicorn or on the daily from Aluminium?
It is correct
Except that there is bottom melt, but that sure be taking off slowly. Who knows, no IMB buoys anymore

14
Arctic sea ice / Re: SMOS
« on: June 19, 2019, 06:38:47 PM »
I imagine (= guess - based on what I've been hearing for years) when the sensor responds with "purple", it is sensing an area that has more dry spots than when it responds with "red", and has 100% nothing to do with ice thickness (except for where it is sensing actually dry thin ice).

Studying the map closely reveals that the story you imagine is probably wrong.

The pixels are arranged in a continuum according to thickness.

The pattern on the map reveals no deviation in the continuum. You don't see any purple areas adjacent to any green areas. Yellow always has green on one side and orange / red on the other. This is exactly what one  would expect to see with a body of ice that is thickest in the center and melting from the shallow sections toward the thick sections.
.
It is unrealistic to expect that surface moisture would appear along a continuum like that. .

This appears to be an ASIF legend that has gotten traction over the years. I'm challenging the legend.
I think I am probably approximately correct, still.  From SMOS (via Oren)
Quote
In the melting season, the thickness of sea ice is highly variable and the emission properties in the microwave change due to the wetness of the surface and occurrence of melt ponds in the Arctic.
My experience of drawing topographic maps from surveying data tells me that a map with a 40 km grid with points of presumed thickness (or wetness) across it can have a topographic-like map drawn over it, creating continuous lines of demarcation between areas of equal thickness (wetness).

Old fashioned reason tells me that the juxtaposition of the thickest ice on the Arctic Ocean (residing perennially in the area north of the CAA) with a zone of SMOS-determined thin ice (presuming non-beige color means variations on thin) is not tenable.  Given that the publishers of the SMOS data declare their data is not useful for thickness determination during the melting season, I can conclude that the colored zones do not describe any aspect of thinness when the surface has degrees of wetness.

This does not mean I am right.  But you are probably wrong.  The ASIF legend lives a little longer!  :)

15
Arctic sea ice / Re: SMOS
« on: June 18, 2019, 11:57:45 PM »
The number of beige pixels for 2019 has been slightly below 2012 in the last 3 days.  But it may also be interesting to have a look at the other colors in the SMOS images.  Note that 2019 currently has relatively many of the purple/violet/red/orange-ish pixels, especially when compared to 2012.  To quantify this, I run a pixel-counting algorithm for several color segments of the SMOS color legend, for the date 17 June, see the bottom chart below (blue pixels are ignored, and I made some heuristic corrections for data gaps for the years 2010 and 2011).






16
Arctic sea ice / Re: "Stupid" Questions :o
« on: June 18, 2019, 03:16:17 AM »
RE Nanning #1886
     The guy who built and runs Climate Reanalyzier (CR) (Sean Birkel) is precise with his terminology.  While I can't be 100% certain since I have not asked him, I'm pretty sure if it was using median he would labeled it "median", not average.  So I can almost guarantee that "average" indeed is the average (mean) for both for 2M temperatures and for anomaly. 

     Furthermore, he says this in an explanatory note on multiple CR pages
"2m Temperature refers to air temperature at 2 meters above the surface. 2m Temperature Anomaly refers to the departure of the current day (or hour) forecasted temperature from a long-term mean for the same day (and hour) of the year. The anomalies here are based on a 1979-2000 reference climatology derived from the NCEP Climate Forecast System Reanalysis (CFSR). This 22-year baseline is used instead of the more common 1981-2010 climate normal because 1979-2000 represents conditions prior to rapid Arctic warming and sea-ice loss."

   Speaking of CR, note that it uses GFS, and that last week after the June 12 transition to the new version of GFS there was an issue with temperature values.   CR had a cautionary note to that effect last week, but now I can't find it, so perhaps the issue has been resolved.  But as of June 17 there is still a cautionary notice on Karsten Haustein's 2M temperature anomaly graph at http://www.karstenhaustein.com/climate.php

17
Arctic sea ice / Re: "Stupid" Questions :o
« on: June 18, 2019, 02:00:31 AM »
RE Lefty Larry "I will keep lurking and keep asking questions."
"I want to know more."

    While ASIF community is great and appreciated, and THE best place to watch the Arctic ice melt, there are better places to understand the big picture regarding scientific consensus and implications of the climate crisis.  Instead of having to figure it out ourselves with limited time, resources, and expertise, wouldn't it be great to convene a bunch of experts in every arena of climate, meteorology, impacts on agriculture, health, economy etc. to look into these very questions?

     Yes, it would.  And it has already been done, repeatedly, by many countries and of course, by the U.N. too (IPCC).  A great example, updated only 6 months ago in fall of 2018 is the U.S. National Climate Assessment at
https://nca2018.globalchange.gov/.  It is written from/for a U.S. perspective of course, but I sense that is your residence and thus of most immediate concern.  The report website provides nice summaries and graphics so you can quickly get to the bottom line.  You don't have to guess at what's going on. 

     People who study this stuff every day for entire careers have given their time to tell us what's going on.  Just because politicians who are ideologically blinded by fossil fuel interest and status quoism ignore blatant facts does not mean you have to be as willfully ignorant as they are.  Indeed U.S. polling shows that despite wildly successful programs to delay response to the crisis by sowing confusion and doubt, a majority of U.S. residents are coming to understand that yes humans can, and are, interfering with the climate system we depend upon for life support on spaceship Earth. 

     Or go to https://skepticalscience.com/  to find scientifically reviewed and credible responses to flawed arguments and bogus "evidence" that have been used in attempts to contradict the scientific consensus.  Read up, think about those grandkids, and decide what is the defensible reply you can give to them, and to yourself, 10 years from now when they ask you what you were doing with your political activity when the climate crisis emerged as a clear and present danger back in 2019.   

     (BTW, the denier industry used the same methods and in some cases even the same consultants as was done in fighting the tobacco smoking - cancer connection, this is not innuendo, but fact.  One of the consultant agency's motto, actually written in a memo: "Doubt is our product." )

18
Arctic sea ice / Re: The 2019 melting season
« on: June 17, 2019, 09:44:36 PM »
As a layman, I don't really know what I'm talking about, so maybe someone can help me out. Frivolous, who seems to speak with some amount of authority/expertise, is posting 5-10 day forecasts; how much attention should we pay to those? I know that temp forecasts beyond a few days out are often wildly inaccurate, are long-range MSLP forecasts typically better?

It depends. Typically there is high variability around D5 on operational runs, e.g. GFS and ECMWF. If there is consistency between multiple runs, it may be indicating a pattern that models have higher confidence on appearing.

For anything past D5 we should only be posting ensemble model outputs instead of operational runs, e.g. GEFS and EPS, but we often don't. These ensemble runs are like their operational counterparts, however the initial conditions are modified slightly for each ensemble member to generate a spread of outputs that can better find divergent states or more confidently show that there is convergence on a given single state. The output for things like 500mb heights in ensembles then represents the blended state across all ensemble members rather than the single expected state that one model run sees.

19
Greenland and Arctic Circle / Re: Greenland 2019 Melt Season
« on: June 16, 2019, 09:32:52 PM »
Looks like another huge melt event just happened.

The whole southern half of Greenland that is.

GIF showing 16.04. ~10:00h to 16:00h UTC

20
Arctic sea ice / Re: The 2019 melting season
« on: June 16, 2019, 02:37:12 PM »
Strong winds blowing warm air off of the Eurasian continent, like we have seen for the past week will be capable of opening up a large area of blue water quickly. This will increase the albedo warming potential if it continues. Rapidly melting out the thin ice on the Eurasian side is a more effective way to reach a record minimum because of the drop in albedo when the ice is gone.

I don't think the CAA is irrelevant but in a year with relatively high ice transport out of the Fram and Nares straits, it's not critical. When the winds are anticyclonic there is little transport through the CAA and when the winds are cyclonic over the central Arctic, it's generally cool.

In conclusion, I don't think the CAA is all that important in reaching a new record minimum if the other more important factors are in place.

21
Arctic sea ice / Re: The 2019 melting season
« on: June 15, 2019, 11:36:49 PM »
Ruth Mottram (a climate scientist at the DMI) posted this image on Twitter a little while ago. 

It is a Sentinel2 image from today of Inglefield Bredning, the location of the sled dogs in Jim Hunts post #1841.

The melting in far northwest Greenland this early in the year is remarkable.

... and to add some historical context, here it is in worldview, along with the same time in 2012 + 2016 ...

22
Arctic sea ice / Re: The 2019 melting season
« on: June 15, 2019, 01:59:52 PM »
SMOS (satellite microwave measurements) beige pixel count on the University of Bremen maps has just dropped to second lowest in the years from with data, beginning from 2010, on the latest date for which the Bremen SMOS map is now available: 14 June 2019.

That ranking is according to the very useful graph that Steven puts out.


The beige pixel count provides a measurement of the area of Arctic sea ice that has NOT yet been wetted by (mainly) melt ponds, and that is therefore still reflecting most of any direct sunlight rather than absorbing it as heat.

So a lower beige pixel count corresponds to more of what Neven calls 'melting momentum'.


For 14 June, this year, 2019, is still well above the anomalous year 2012 and is just below the 3rd lowest year, which is 2016.

A large part of the reason for the drop into second place is the notable appearance of non-beige pixels on the Canadian+Greenland side of the Arctic sea ice on 14 June 2019, indicating the onset of significant surface melting there.

23
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: June 15, 2019, 01:15:20 PM »
No need to resource to a possible change in the ice. The ice has changed, is younger and a 10-20% thinner, or so. But  it's still ice.
There is a surface melting event of (un) precedented reach (since 2012) so NDSIC area goes down because it's too sensitive to surface melt, it even "sees" open ocean where there is not.
Extent is not sensitive, the way it is constructed from same ice concentration data. It does not mistake surface melt by ocean, praised be.
Storms cause ice divergence, a separation of big and small floes between themselves like Mr Wilson and Tom Hanks.
Many of these separations are small growing cracks in regions that had been compacted by the previous anticyclone.
Right now two storms are beating regions very prone to this dispersion and divergence: Beaufort and Kara-Barents.

24
Arctic sea ice / Re: Arctic Image of the Day
« on: June 15, 2019, 06:47:10 AM »
... when we see deep blue on the fast ice on Worldview... is this sometimes what we are looking at???



On worldview, it looks like pic 1
On Sentinel, it looks like this pic 2 (this picture is taken 2 days before, i selected it because of the cloudiness, on 13th it's all blue.)
On RAMMB Slider, in Natural Colour, it looks like pic 3
On RAMMB Slider, in Geo Colour, it looks like pic 4

25
Arctic sea ice / Re: The 2019 melting season
« on: June 15, 2019, 12:49:33 AM »
unihamburg amsr2uhh overlaid onto ascat with 100% ice (normally white) set to transparent. The amsr2 overlay is 70% transparent to allow other features of ascat to show through, notably greenland. It also helps to make the 'weather' over open water less distracting.
Similar to last year the wash of warm weather has revealed fractures in the older ice that were not visible previously.
jun1-13
thanks to A-Team for helpful hints, some of which need further work
https://forum.arctic-sea-ice.net/index.php/topic,2558.msg205561.html#msg205561


26
Comparing meltponds June 14 2019.

27
Antarctica / Re: Halley base shut down and new crack in Brunt shelf
« on: June 14, 2019, 08:01:47 PM »
From Adrian Luckman:  animation of the McDonald Ice Rumples on Brunt Ice Shelf

https://adrianluckman.wordpress.com/2019/06/14/mcdonald-ice-rumples-on-brunt-ice-shelf/


28
Arctic sea ice / Re: The 2019 melting season
« on: June 14, 2019, 01:55:19 AM »
I will apply the term 'catastrophe' to the melting of the ice 'up north' without feeling any sense of exaggeration . The catastrophe of the ongoing thaw/melt in the East Siberian and Laptev seas is that it is another of the boxes ticked on the way to a season melt-fest .
 As A-team points out such weather is secondary to the real story of the season .. the unprecedented export of a large part of the multi-year ice to destruction . The export continues over the coming week with the wind blowing from the ESS/Laptev toward Barnetz/Fram . A large part of the remaining older ice will move into the killing zone to make way for the new ice so it can make way for open water .
  One of the results is that much of the colder air in the forecast is in Barnetz and Kara while the Siberian / Pacific side of the Arctic basin is basking in temperatures we in W Europe would appreciate atm.
 Then there was the snow .. strong arguements that extra snow on shore and ice would help delay the melt. No snow on shore or on onshore ice ..
 So I agreed with AM2's anguish at seeing yesterday's SMOS image . Even if it may not accurately reflect reality , it does reflect ongoing melt and the melt is going on and on , as am I . :)  b.c.

29
Arctic sea ice / Re: The 2019 melting season
« on: June 13, 2019, 07:27:10 PM »
A blowtorch went over the Lincoln Sea and then also Greenland.

This is a GIF showing 11.06. 02:11h to today 13:25 in M8 band. Bottom right is Greenland.

Jay found out what the darkening means exactly in this band. Read all about it here >> https://forum.arctic-sea-ice.net/index.php/topic,2649.msg205401.html#msg205401


30
Greenland and Arctic Circle / Re: Greenland 2019 Melt Season
« on: June 13, 2019, 01:19:41 PM »
North Greenland. That glacier at Nares Land.

(Click to play)

31
Arctic sea ice / Re: The Rammb Slider Thread
« on: June 13, 2019, 01:03:21 PM »
VIIRS potential for snow retrievals

Several VIIRS bands have good sensitivity to snow structure, especially SWIR bands M8,10,11
Overlaid curves show model snow albedo for various grain sizes

Link >> https://collaboration.cmc.ec.gc.ca/science/rpn/SEM/dossiers/2012/seminaires/2012-11-23/Seminar_2012-11-23_Alexander_Trishchenko.pdf

32
Arctic sea ice / Re: The Rammb Slider Thread
« on: June 13, 2019, 08:32:03 AM »
Amazing animation.
So does the dark color represent wet surface or warmed surface?

I don't know if it's surface temperature or snow wetness or a combination of both.

I did saw the ESS darkening in M8 and M10 band like 2 days before melt ponds became visible in Sentinel.

Also the Greenland darkening Jay posted, corresponds directly to rising temperatures.

I made GIFs showing this in detail. First GIF is yesterdays temperatures on the east coast with time stamps. If you compare the Greenland darkening (in M10 band) GIF 2 (Click to play), it corresponds directly to the rising temperatures.

So i guess the question is, would ice and snow melt that fast or is it temperature we are seeing?

33
Greenland and Arctic Circle / Re: The Nares Strait thread
« on: June 13, 2019, 07:41:24 AM »
Warmth just burned over Lincoln. I totally expect the next Sentinel shots to show melt ponds.

8)

34
Greenland and Arctic Circle / Re: Greenland 2019 Melt Season
« on: June 12, 2019, 04:30:39 PM »
Oh, boi.

This is Greenland west coast in the M8 band.

That darkening means melting.

35
Arctic sea ice / Re: The 2019 melting season
« on: June 12, 2019, 12:10:56 PM »
10.06. vs. 12.06. - ESS

(Click to play)

36
Arctic sea ice / Re: The 2019 melting season
« on: June 12, 2019, 11:02:09 AM »
2012.6.12-2019.6.12 which one is worse

37
Arctic sea ice / Re: The 2019 melting season
« on: June 12, 2019, 10:26:25 AM »
The ESS joining the Laptev, with "melt-pond blue" intensifying

Looks like this in M10 band (07.06. 12:45h to 12.06. 05:15h UTC). You can literally see the heat moving.

In this GIF, a lot of frames are skipped to erase the stills. Click to play!

38
AMSR2 animation the scene.

https://twitter.com/seaice_de/status/1138007405369942016

As always click to play

39
Arctic sea ice / Re: The 2019 melting season
« on: June 10, 2019, 11:16:05 AM »
Laptev, ESS and Greenland coasts are getting (and will continue to get) absolutely blow-torched

Case in point:

40
Greenland and Arctic Circle / Re: The Nares Strait thread
« on: June 10, 2019, 06:36:51 AM »
Same boom as a GIF.

41
Developers Corner / Re: Test space
« on: June 09, 2019, 05:28:38 PM »
I am testing below for differences between U Bremen's SMOS vs SMOS-SMAP maps for ice thinness. Recall the M in both stands for soil moisture; their data (like Ascat's) has been re-purposed for sea ice. The latter brings in synergistic data from a second satellite to correct and enhance the former.

Since the advent of v205 of SMOS-SMAP, there seems to be no justification for using plain SMOS, other than it has a much longer consistent archive (ie same algo versioning) and a one day  shorter lag-to-archive posting. SMOS is riddled with flash artifacts. Both are observational data that have been vetted in the field, unlike Piomas.

SMOS-SMAP is provided at a vastly better resolution (2.83x), measured as Gimp pixel counts on the (polar stereographic) line between St Lawrence Island in the Bering Sea and Bear Island in the Barents (these are consistently visible in both pure imagery and in archival base maps).

That distance is 4738 km (2558 nm) as measured in WGS84 on Google Earth Pro. Accurate pixel counts are the key to re-sizing images to matching overlays:

satellite      pxl       %      ~km/pxl    ~km^2/pxl
SMOS          397.5    75.815   11.92      5.06
Ascat         524.3   100.000    9.04      6.67
OsiSaf       1075.5   204.711    4.41     13.66
SMOS-SMAP    1146.0   218.577    4.13     14.59
AMSR2        1197.6   228.419    3.96     15.24


Both satellites max out (to beige) in the central Arctic during the freeze season, as the ice pack quickly thickens beyond their 0.5m sensing capability. However, certain peripheral areas do not thicken to this depth at any time during recent winters. Thus SMOS-SMAP provides nuanced data during months when AMSR2, Ascat and WorldView see nothing but ice surface.

It's not possible yet to see how the two thinness maps compare during melt season, nor is it clear what they measure or conflate in summer, the possibilities being ice thinness, melt ponds, rafted ice, refrozen melted snow, slushy floes, liquid cloud water, or artifacts from passing storms.

Rather than throw the baby out with the bathwater (not use in summer), it might be better to take (locationally consistent) SMOS-SMAP colors as the thin or dodgy ice, that ice most vulnerable to melt-out. This interpretation interpret very well with the peripheral location of thinness colors both during fall freeze-up of 2018 and into early June of 2019.

The mp4 below is a 266-day hybrid map showing SMOS from 15 Sep to 31 Dec 2018 concatenated to SMOS-SMAP from 01 Jan to 07 June 2019. I originally made it to 700 pixel width but because the center stays so dark and is so large, it views better at 550 width. While moderately difficult to make, the final product only takes up 4-5 MB at 16-20 fps frame rate.

Note the very rapid expansion of dodgy ice in the last few days in the Beaufort-Chukchi and above the Svalbard-FJL-SZ line.

The freeze/melt cycle is largely a story of peripheral ice freezing, moving with the wind, and then melting to an extent determined by whatever weather summer brought. In most years the sub-central ice pack is not noticeably affected (though in fact multi-year ice is on a disappearing trend).

This year the lower CAB has experienced unusual displacement towards the CAA, Fram and Beaufort arm. The area has been cloudy enough that the main region of thick old ice has rarely been visible in Worldview, though intact ice with brittle healed leads can be seen after enhancement.

The contribution of SMOS-SMAP is thus to the near-miss zone: ice that thinned to 0.5m and below but did not quite melt out (or become visible as low concentration by AMSR2) by end of season. It is likely more informative than sketchy albedo and melt pond products earlier in the season as these do not measure either top or bottom melt.

The last three weeks of Ascat are also showing weather streaking across the scene, sometimes leaving permanent effects on radar brightness (ice near-surface dielectric), both lightning (less polarizable constituents) and darkening (more saline or more liquid).

42
Arctic sea ice / Re: The 2019 melting season
« on: June 09, 2019, 02:00:57 PM »
Some fast ice is beginning to pulled away in the ESS. (First attachment,  band I1 with I3 overlay.
http://rammb-slider.cira.colostate.edu/?sat=jpss&z=4&im=18&ts=1&st=0&et=0&speed=120&motion=loop&map=1&lat=0&opacity%5B0%5D=1&opacity%5B1%5D=0.5&hidden%5B0%5D=0&hidden%5B1%5D=0&pause=20190609043123&slider=-1&hide_controls=0&mouse_draw=0&follow_feature=0&follow_hide=0&s=rammb-slider&sec=northern_hemisphere&p%5B0%5D=band_i01&p%5B1%5D=band_i03&x=12211.4375&y=18844.78125


Second attachment is the EURO ensemble 5 day average sea level pressure. It screams slow extent loss.  Winds have reversed int the Chukchi already, and an amazing ice edge is visible inch thr RAMMB slider.  We should also see ice getting dispersed in the Beaufort for the time being.  The one constant is the push towards the Atlantic.  The ESS and Laptev will see persistent southerlies, and likely the most impressive extent declines.
  This isn't to say melting will halt, in fact, is should transport ice to areas it could melt quicker.  It'll be interesting to watch the floes reaction in the Chukchi in particular.
I guess this illustrates a cold low over Beaufort and a warm low over Laptev (edit: warm front)
We should expect now some acceleration in area decline, compactness down. Beaufort is still cold but that low scattering the floes and stirring the preheated waters is slow bottom-melt slaughter we have seen other years.

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As the flow exits the fjord, is the light color of the water extending outwards all brash ice or is it also due to sediment?

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A zoom in on the elastic slush.

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Arctic sea ice / Re: The 2019 melting season
« on: June 07, 2019, 03:19:02 PM »
More Lena Delta.

This time from Sentinel

(Click to play)

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Arctic sea ice / Re: The 2019 melting season
« on: June 07, 2019, 10:28:32 AM »
Random floe in the Beaufort Sea. You can clearly see how it cracks along the pinkish ice which i suspect to be a frozen melt pond.

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Arctic sea ice / Re: Do we make too much of 2012 ?
« on: June 06, 2019, 05:53:04 PM »
I don't think that we make too much of 2012, because 2016 looks much worse. And 2012 looks worse than 2007. Neither 07 nor 12 was a one-time event - it's a trend.
True, 2012 had smaller extent than 2016, but if I look at the Uni-Bremen ice concentration maps, I can see, that we had much less "solid" ice in 16 than 12 (sea ice concentration maps on Sep 1, purple is 100% ice concentration, 16 above, 12 below):

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Arctic sea ice / Re: The 2019 melting season
« on: June 05, 2019, 11:37:28 PM »
Sentinel images of Lena water spreading out over ice, over 3 days.

Click to animate

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Arctic sea ice / Re: The Rammb Slider Thread
« on: June 05, 2019, 01:09:12 PM »
80 hour loop of the Lena delta, ending June 5, 0Z

Looks like this in Geo vs Natural

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Arctic sea ice / Re: Latest PIOMAS update (May 2019)
« on: June 05, 2019, 12:35:09 AM »
Thickness Anomaly, but yes the parts that usually have thicker ice and are likely to not melt have less ice and areas that have ended with above average ice thickness are all about to go bye-bye into the Atlantic. Discouraging indeed.

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