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Messages - uniquorn

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1
Arctic sea ice / Re: The 2019 melting season
« on: Today at 01:06:24 AM »
north whirlpole then ;)

2
Arctic sea ice / Re: The 2019 melting season
« on: May 26, 2019, 12:07:54 PM »
< it seems like the Beaufort expanded and solidified, almost as if a refreeze was going on. I would say it's probably a removal of the effect of clouds on the sensor, or a freezing of surface meltwater on the ice, but would like to hear more expert opinions.>
I'm no expert but with air temperatures mostly above zero and a quick look at worldview I wouldn't suggest freezing ;)
worldview, aqua modis, beaufort to fram, may25

3
Arctic sea ice / Re: Arctic Ocean salinity, temperature and waves
« on: May 26, 2019, 12:26:28 AM »
for reference, a rough overlay of global hycom cice ice thickness (GLBb 0.08-93.0) over ascat at 42% transparency.

4
Arctic sea ice / Re: The 2019 melting season
« on: May 23, 2019, 10:55:09 PM »
Please take the polar bear discussion to the appropriate thread, maybe this one https://forum.arctic-sea-ice.net/index.php/topic,2348.0.html

Despite the drift, the atlantic side north of FJL/Svalbard is also not looking good.
edit: worldview aquaterra modis, may21-23 https://go.nasa.gov/2M7P0lt

5
Arctic sea ice / Re: The 2019 melting season
« on: May 20, 2019, 11:00:18 PM »
edit: arctic ocean today. Slight contrast adjustment to highlight fractures. https://go.nasa.gov/2JVe10v

6
Arctic sea ice / Re: The 2019 melting season
« on: May 19, 2019, 10:10:36 PM »
ascat and uni-hamburg amsr2-uhh (both heavy contrast) overlaid onto mercator 34m salinity. Ascat showing approximate ice age, amsr2 showing more fracture detail. Salinity somewhat lost under the other 2 layers but reddy brown is salltier than greeny yellow saltier than blue. sep24-may18.
Note the incoming weather event from the pacific on day117(0427)
tricky to get the scaling and overlay to match up. The ice matches better than the lat/long lines



7
Arctic sea ice / Re: The 2019 melting season
« on: May 17, 2019, 09:58:54 PM »
Comparison of 2019 and 2016 using unihamburg amsr2-uhh, mar20-may16, pacific side.
Some concentration data has been sacrificed during processing so this should only be seen as a guide. Some days are missing data

8
Arctic sea ice / Re: The 2019 melting season
« on: May 17, 2019, 12:41:21 PM »
The whole Arctic pack is rotating clockwise now. The ice has transform faults all around the CAA and Greenland. Faults are continuous in ice on the north of Ellesmere island on today's Aqua image.
A bit of a 'hill start' but ice north of caa definitely joining the rotation now.
Worldview terra modis may10-16. https://go.nasa.gov/2EinfAu

9
Arctic sea ice / Re: Arctic Ocean salinity, temperature and waves
« on: May 15, 2019, 11:01:57 PM »
Yes. Still looking at it. Here's ascat overlaid onto unihamburg amsr2uhh(heavy contrast), apr24-may14. I still think it's the push from the pacific into the chukchi that causes it. There's a compression from the atmospheric weather into the caa then upwelling or disturbance when the waves hit along the coast. Then reflection out into beaufort.
Will try to look more at the hycom ani tomorrow. It's a better illustration of the movement.
edit:not related, but interesting how the fractures north of ellef ringnes match up with the scatter difference.

10
Arctic sea ice / Re: The 2019 melting season
« on: May 15, 2019, 02:29:27 PM »
'On the ice' temperatures from whoi itp buoys. 4 of them reporting above zero temperatures recently. https://www.whoi.edu/page.do?pid=163197

11
Arctic sea ice / Re: The 2019 melting season
« on: May 12, 2019, 11:32:16 AM »
ecmwf and gfs indicating temperature around -4C in that area of Laptev. Refreeze? A bit too cloudy to tell. edit: correction, there is refreeze https://go.nasa.gov/2JBxqDp

uni-hamburg amsr2-uhh, may4-11 showing the fracture spreading west to east along the CAA coast.
Worldview viirs brightness temperature (band15) night appears to show a surge continuing eastward around the north of greenland.
Something else happening as well as the possible currents indicated upthread.
edit: Southerlies on the 7th, cyclone on the 8th dragging more southerlies along the coast maybe? Small cyclone in Lincoln today.

12
Arctic sea ice / Re: The 2019 melting season
« on: May 11, 2019, 10:07:09 PM »
Mercator (model) salinity 0m and 34m indicating a surge of atlantic water around north greenland combined with returning atlantic water from the north. The surge may be temporary, the other isn't.

The CAA coast isn't looking too good either. https://go.nasa.gov/2DYOu2z
@b_l nice, but there are many repeat frames in that ani

13
Greenland and Arctic Circle / Re: The 'Very Big Chunk' poll
« on: May 11, 2019, 07:20:02 PM »
I really want this plucky floe to save the Lincoln sea single handedly. It's only a flesh wound ;)
replaced image with today's aqua, terra, viirs(suomi/npp)
This method does appear to show tidal movement. By the way, does this rule out 'not!' or does it have to stay put for 24hrs ?
edit: added this morning's image to the animation. It's a shame it's so warm there today.

14
Arctic sea ice / Re: The 2019 melting season
« on: May 11, 2019, 07:11:22 PM »
Lincoln Sea ice not looking good today.
Worldview aqua modis, may10-11 https://go.nasa.gov/2E47pcm

15
Walking the walk / Re: Gardening
« on: May 10, 2019, 04:20:59 PM »
I've been getting ideas from this thread for a long time so I think it's time to join in. Early fava (broad,field) beans are doing really well but so are the ants farming blackfly. I spray with a mixture of soap, neem and teatree to slow them down. Any suggestions? Early peas and spinach failed this year as did the flax for some reason. Fenugreek survived. It's a lottery.

A couple of pictures of the plot.
Top. Last years spinach. Beans to the right of hops in front of rhubarb and asparagus. The poly was a gift from someone moving.
Bottom. 2nd year we've tried potatoes in mulch. These are on top of 2years of alfalfa. BIG roots! Soon we'll put old hay on top (no straw here). Leeks, onions, garlic and brassicas above. We try no till but with my planning skills we mostly end up digging. You can just see the four sheep at the top keeping the field down (or gazing into space, chewing). 5 hens and a cock probably being naughty somewhere. It's never tidier than this.

16
Arctic sea ice / Re: The 2019 melting season
« on: May 09, 2019, 09:31:01 PM »
Actually, just saw on Aqua / MODIS, there even is a third crack directly alongside the Canadian coastline.
Yesterday's worldview aqua modis of the same area, close to prince patrick. A small cyclone moving eastwards from amundsen gulf has lifted what should be some of our thickest ice from the CAA coastline. More disturbing (to me) are the fine lateral fractures which have little chance of refreeze.
3 more days of southerlies are forecast. Default and enhanced contrast.

17
Arctic sea ice / Re: The 2019 melting season
« on: May 09, 2019, 05:36:30 PM »
I don't think they rise to the surface. That area was the last to melt last year. The ess arm has been
if not rise to the surface, what about reach the surface by displacement, is that a term that would suit your opinion or do you assume that things stay the way they are now?
You would have to describe in more detail what would be displacing what. It's possible there is some mixing, but looking at the bouy data it takes a big event to disturb the halocline layers.

18
Arctic sea ice / Re: The 2019 melting season
« on: May 09, 2019, 02:38:30 PM »
Not much warmth in the pacific inflow as yet, just salinity. Atlantic water more dominant in the Laptev than last year (according to the model) Mercator salinity 0m, mar1-may7
That's basically where the Atlantic waters turn the corner after flowing along the Eastern continental shelf of the Nansen basin, heading back north. I wonder if there is a) shoaling causing deeper waters to rise and b) if that water is warmer than usual.
I don't think they rise to the surface. That area was the last to melt last year. The ess arm has been stretched and refractured all last freezing season. It's probably just thin ice.
salinity/ascat here: https://forum.arctic-sea-ice.net/index.php/topic,2417.msg193927.html#msg193927
bathymetry/ascat: https://forum.arctic-sea-ice.net/index.php/topic,2417.msg193927.html#msg193927
Perhaps it hasn't really been that cold on the pacific side last freezing season.
polarportal ice surface temperature, sep24-may8
edit - forgot scale

19
Arctic sea ice / Re: Arctic Ocean salinity, temperature and waves
« on: May 08, 2019, 10:08:52 PM »
whoi itp110 for Bruce Steele. The warm layer getting thicker again as 110 drifts south west.

20
Arctic sea ice / Re: Arctic Image of the Day
« on: May 08, 2019, 12:37:20 AM »
South west tip of Greenland today  https://go.nasa.gov/2Jlwh2Q

21
Greenland and Arctic Circle / Re: The 'Very Big Chunk' poll
« on: May 07, 2019, 07:42:29 PM »
A zoom on the Nares Strait using AMSR2 data 2013-2019.
https://twitter.com/seaice_de/status/1125354599282610177
Thanks seaice.de. I spent a long time looking at those animations. For those who didn't click on the link here is the sentinel ani.

22
Arctic sea ice / Re: Arctic Ocean salinity, temperature and waves
« on: May 07, 2019, 01:45:30 PM »
update on amundsen gulf, worldview aqua modis (clearer) may7, heavy contrast. This area only frozen fast since apr1.

23
Greenland and Arctic Circle / Re: The 'Very Big Chunk' poll
« on: May 06, 2019, 07:25:43 PM »
Well, to be fair, it doesn't look that solid on the ice age map either. That's the end of my optimistic voting for this year.

24
Arctic sea ice / Re: The 2019 melting season
« on: May 06, 2019, 12:32:53 PM »
I like the long range forecasts. The melting season threads have always been full of them (as far back as I've gone). I would like them a lot more, and learn more, if the OP posted reanalysis on them 10days later. or20d ;)

25
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: May 06, 2019, 10:30:49 AM »
2019 for all intents and purposes, is currently following 2016's track.  The difference is well within the margin of error.
Extent numbers are similar, the location of the ice is quite different. Click to run

26
Greenland and Arctic Circle / Re: The Nares Strait thread
« on: May 05, 2019, 02:17:09 PM »
Possibly the most turbulent while the others have fast ice.

27
Arctic sea ice / Re: Arctic Ocean salinity, temperature and waves
« on: May 04, 2019, 09:32:37 PM »
nasa nsidc daac ease-grid sea ice age v4.1 for 2018 (cropped to >1yr ice to reduce file size)
OT but here for ref

28
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: May 04, 2019, 05:53:21 PM »
Amazing how much of the ice exiting and set to exit the Fram is 1st year ice.
Refreeze between fractured 2-4yr ice perhaps

29
Greenland and Arctic Circle / Re: The 'Very Big Chunk' poll
« on: May 04, 2019, 01:16:48 PM »
maybe vbc is over 4yrs old... parts of it
OT edit:surprised there's no 1-2yr in the chukchi

30
Arctic sea ice / Re: Arctic Ocean salinity, temperature and waves
« on: May 03, 2019, 10:06:07 PM »
Worldview terra modis amundsen apr1-may2
uni-hamburg amsr2-uhh mar19-may2 2016 overlay

31
Arctic sea ice / Re: The 2019 melting season
« on: May 03, 2019, 06:39:27 PM »
A comparison of 2019 and 2016 using uni-hamburg amsr2-uhh apr1-may2.

32
Arctic sea ice / Re: The 2019 melting season
« on: May 03, 2019, 11:19:41 AM »
On the ice temperatures from the whoi itp bouys 104-110. Interesting that they indicate slightly warmer temperatures than nullschool today. (I rarely compare them)
Both 107 and 110 briefly >0C recently   https://www.whoi.edu/page.do?pid=163096
itp103 hasn't reported since apr30 :(

33
Greenland and Arctic Circle / Re: The 'Very Big Chunk' poll
« on: May 02, 2019, 08:31:53 PM »
The white dot on ascat image day2018260 is an attempt to trace vbc back to the begiinning of the freezing season. (please check)
https://forum.arctic-sea-ice.net/index.php/topic,176.msg197396.html#msg197396
That area was far enough north to escape export into the CAA in 2017-18 (see 2010-feb 2019 to check
https://forum.arctic-sea-ice.net/index.php/topic,2417.msg188990.html#msg188990 )

Tidal range is low at the moment, light winds. Maybe vbc has a chance to hold together for a few days. Todays lift off from the eastern side of the Lincoln sea doesn't bode well though.
https://go.nasa.gov/2DLPZRG

34
Greenland and Arctic Circle / Re: The 'Very Big Chunk' poll
« on: May 01, 2019, 09:15:33 PM »
ok. Voted without discussion ;)

35
Arctic sea ice / Re: The 2019 melting season
« on: May 01, 2019, 12:26:00 PM »
This image is based on yesterday's Modis image with bands 7-2-1 overlayed with the daytime ice surface temperature using a compressed palette. Yellow has been calibrated to around 273 K (with orange-red being warmer), so the idea is to an alternative indication of where surface melt is likely:
Thanks for this, useful in areas where there are no clouds.

36
Greenland and Arctic Circle / Re: The Nares Strait thread
« on: April 30, 2019, 11:56:21 PM »
Fancy equipment  :)
Probably more detail on sentinel but here is worldview terra modis local contrast today of 'very big chunk'. It has a few faults. Fast ice at the entrance is starting to look a bit challenged. edit: I see it already lifted off and probably won't refreeze properly now.
Also ascat freezing season to present. The arches haven't survived for long.

37
Arctic sea ice / Re: The 2019 melting season
« on: April 30, 2019, 09:51:57 PM »
On the ice measurements from whoi itp103-110.
itp107 closest to Chukchi latest reading -0.625C   https://www.whoi.edu/page.do?pid=163096

38
Arctic sea ice / Re: The 2019 melting season
« on: April 26, 2019, 10:35:21 AM »
Combining 2 images - April 25th on the left, and April 21st on the right to take out cloud -  you can see the broken ice is joined together now. I looked back in the years, and don't see this any other year doing that at this time of year. 2010 comes close on May 4th. A cracked and fractured icesheet from Nares to Fram now.
Agreed. edit: I should add that it is still cold enough for refreeze in those fractures, but the drift is too fast to make much difference.
Worldview terra modis, north greenland, apr8-24. Contrast enhanced to show fractures. 7days/sec.
More about nares here https://forum.arctic-sea-ice.net/index.php/topic,176.msg196830.html#msg196830

39
Arctic sea ice / Re: The 2019 melting season
« on: April 25, 2019, 08:33:41 PM »
JAXA RGB, jan1-apr24.

40
Greenland and Arctic Circle / Re: The Nares Strait thread
« on: April 23, 2019, 09:07:35 PM »
HapHazard must be psychic. Here is a dotty idea for Nares.
NOAA bathymetry overlaid onto ascat day95-107 with dots running down Lomonosov ridge. 7days/sec.
edit:scale doesn't apply as overlay changes hues but blue=deep, green=mid, sepia=shallow
No idea if any sort of wave moves at that speed hence dotty.

41
Arctic sea ice / Re: Arctic Ocean salinity, temperature and waves
« on: April 22, 2019, 09:47:54 PM »
mercator-salinity-0m-34m-92m-318m--arctic-jan1-apr21.
Had this set up for nares, posting full arctic for ref..

42
Greenland and Arctic Circle / Re: The Nares Strait thread
« on: April 22, 2019, 08:32:30 PM »
This animation cycles through mercator salinity(model) at 0m, 34m, 92m and 318m for jan1-apr21 centring on the nares/lincoln. Cooled, mixed atlantic water from the north on the atlantic side inhibiting the flow towards Lincoln sea of fresher water from the west. Turbulence at entry to the Nares causing mixing all the way down to 318m. Water leaving the Kane basin at 318m is fresher than at entry to the Nares. At 0m and 34m more saline. (If the model is correct)
Perhaps high tides push mixed water that is warmer and more saline back into the Lincoln?

btw do these mp4 work for mac?

43
Arctic sea ice / Re: The 2019 melting season
« on: April 22, 2019, 12:51:17 PM »
uni-bremen smos ftp stops latest data is apr17

On a positive note, ice continues to be compacted into the triangle north west of Greenland.
Worldview terra modis apr1-21. Heavy contrast to show fractures. A faster frame rate helps to look 'through' the clouds. (11days/sec)
edit: replaced gif with mp4

44
Arctic sea ice / Re: The 2019 melting season
« on: April 21, 2019, 04:29:20 PM »
50 days of ascat hopefully working better for mac users
Thanks to Sleepy for the ffmpeg conversion.

45
Arctic sea ice / Re: The 2019 melting season
« on: April 20, 2019, 12:01:47 AM »
Worldview terra modis, amundsen gulf, apr10-19.
Worldview terra modis, amundsen gulf, apr18(or nearest) 2010-2019.

46
Arctic sea ice / Re: The Rammb Slider Thread
« on: April 19, 2019, 10:54:58 PM »
Looking for something about Amundsen Gulf tides found this journal from 1986.

International Hydrographie  Review,  Monaco,  LXIII (2),  July  1986CANADIAN  ARCTIC  TIDE  MEASUREMENTTECHNIQUES  AND  RESULTSby  B.J.  TAIT,  S.T.  GRANT,  D.  St.-JACQUES  and  F.  STEPHENSON (*)
https://journals.lib.unb.ca/index.php/ihr/article/viewFile/23426/27201

Quote
The  tide  in  the  southern  Beaufort  Sea  and  in  Amundsen  Gulf  propagates counterclockwise  about  an  amphidromic  point  situated near the  southwest  corner of  Banks  I.  It  propagates  quickly  along  the  coast  from  Alaska  to  a  point approximately midway along the Tuktoyaktuk Peninsula where it slows significantly,  reaching  Sachs  Harbour (site  4,  Figure  2)  on  Banks  I. about  six  hours  later.  In Amundsen  Gulf the  tide  travels  east  into  Dolphin  and  Union  Strait  and  Prince Albert  Sound  and  northwest  into  Prince  of Wales  Strait.The  tidal  propagation  patterns  in  the  waterways  between  the  eastern  end  of Amundsen Gulf and the southern end of M’Clintock Channel are complex and not yet  well  defined.  Further field  surveys  are  planned  for these  areas.

First image is fig2 from the journal.
Original rammb animation 35MB (80 frames) when cropped was 5MB and very small. Enlarged 2x took it to 18MB. Converting to mp4 gets 384kB. (click to play)
ffmpeg -i rb2.gif -pix_fmt yuv420p -vf "scale=trunc(iw/2)*2:trunc(ih/2)*2" rb2.mp4
Worldview terra modis apr18 (or nearest) 2010-2019posted on melting season (deleted here to help save the planet)

47
Arctic sea ice / Re: The 2019 melting season
« on: April 17, 2019, 11:36:39 AM »
uni-hamburg amsr2-uhh, greenland, apr10-16.
wipneus regional extent  https://sites.google.com/site/arcticseaicegraphs/regional
Southerlies likely to be dominant for the next two days.

48
Arctic sea ice / Re: Arctic Ocean salinity, temperature and waves
« on: April 16, 2019, 11:37:37 PM »
The good people at the woods hole oceanographic institution are once again posting active itp buoy data. This animation only showing those with full depth profiles.
https://www.whoi.edu/page.do?pid=163196

49
Arctic sea ice / Re: Arctic Ocean salinity, temperature and waves
« on: April 14, 2019, 11:18:18 PM »
A comparison of mercator(model) 318m salinity, feb1-apr13, 2018 and 2019. The reason this thread was started.

50
Greenland and Arctic Circle / Re: The Nares Strait thread
« on: April 13, 2019, 12:08:18 PM »
update using worldview viirsbt15n, mar18-apr13. A short slow down in export during mar29-30 probably due to strong southerlies during those days.

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