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uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #100 on: November 23, 2018, 07:25:03 PM »
A very good view of the eddy north of Svalbard yesterday on polarview. Definitely some rotation there.
« Last Edit: November 23, 2018, 07:40:45 PM by uniquorn »

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #101 on: November 26, 2018, 10:24:00 PM »
Quite a storm brewing on the atlantic side this week.
ecmwf wave forecast from windy, nov27-dec5

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #102 on: November 26, 2018, 10:44:46 PM »
Forgot about ice surface temperature.
DMI polarportal, sep14-nov25

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #103 on: December 01, 2018, 06:19:04 PM »
Update on the whoi buoys ITP103-110. Their drift track has been more in line with the annual ice drift recently. ITP107 is showing a deeper lower salinity layer as it drifts closer to the gyre. ITP109 is also starting to show a change in profile. Im not sure how to read ITP110.

Shared Humanity

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Re: Arctic Ocean salinity, temperature and waves
« Reply #104 on: December 02, 2018, 06:17:10 PM »
Quite a storm brewing on the atlantic side this week.
ecmwf wave forecast from windy, nov27-dec5

Those waves have to wreak havoc on the ice in the Greenland Sea. Especially with sea surface temperatures between 0C and -1.5C lurking nearby.
« Last Edit: December 02, 2018, 06:25:41 PM by Shared Humanity »

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #105 on: December 03, 2018, 10:30:30 PM »
More stormy weather is forecast. I'll revisit this one in a few days.
windy-wam-dec3-forecast-for-dec12, atlantic side.

A comparison of mercator temperature at 0m and 34m depth with JAXA RGB from nov1-dec2 in the Chukchi sea. While the JAXA images that I can easily download are smaller (lower resolution) than amsr2 products they do give a better representation of differing ice types.
When the newer thin ice in the Beaufort meets the eddies on the edge of the gyre the interaction can be seen from ~10-17nov. After that, the thicker ice (in blue) is not so responsive and has picked up a lot of momentum from the continuous 25-40km/h winds over the last week.
Chukchi and Beaufort, Mercator temperature 0m and 34m, jaxa rgb, nov1-dec2

edit:added mercator temperature scales
« Last Edit: December 03, 2018, 11:28:47 PM by uniquorn »

oren

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Re: Arctic Ocean salinity, temperature and waves
« Reply #106 on: December 04, 2018, 01:56:47 AM »
Superb graphics/animations, thanks uniquorn.

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #107 on: December 08, 2018, 01:56:59 PM »
Worldview, viirs, bt15day doing a great job yesterday in relatively clear weather with a cyclone over the Beaufort gyre (click on the image for full size). Ice lifting off the CAA tending to confirm the mercator model indicating upwelling east and west of the Mclure strait.
Mercator, CAA, 0m and 30m salinity, nov1-dec7.
edit:added salinity scales. (some of the 0m salinity increase should be brine exclusion from freezing ice, but probably not in the Amundsen gulf or along the CAA coast)

worldview link: https://tinyurl.com/yaszxycm

edit2: Added ascat to the salinity animation.

« Last Edit: December 08, 2018, 08:25:30 PM by uniquorn »

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #108 on: December 09, 2018, 04:19:26 PM »
Ice near the Mclure Strait rotating anticlockwise during the passage of the last cyclone. edit:Probably temporary.
Worldview, viirs bt15n, dec7-9  https://tinyurl.com/y8qnzkyr
« Last Edit: December 09, 2018, 04:24:54 PM by uniquorn »

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #109 on: December 10, 2018, 04:45:14 PM »
Update on Mercator 0m salinity model showing an atlantic push eastward during the recent stormy weather, possibly causing upwelling on the southern Kara sea coast.
The model also indicating upwelling on the CAA/Beaufort and Chukchi coast. I don't know if the increase in salinity along the CAA is due to brine exclusion or upwelling. Wind driven lift off from the coast is visible on Worldview, but it's been very cold so it's likely the fast ice has been weakened from below. Comments very welcome.
Mercator 0m salinity, nov20-dec9 (scale same as above)
« Last Edit: December 10, 2018, 05:14:59 PM by uniquorn »

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #110 on: December 11, 2018, 06:34:05 PM »
The ecmwf wave forecast on dec3 wasn't too bad that far out, though there are pretty large waves most days at the moment. Barents/Kara getting a battering tomorrow but not the CAB.
windy ecmwf wam dec12

edit:
Polarview image yesterday of lower concentration ice north of FJL. Mercator 0m salinity and amsr2-uhh ice concentration inset.
« Last Edit: December 11, 2018, 09:40:29 PM by uniquorn »

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #111 on: December 13, 2018, 10:36:22 PM »
Thanks to Brigantine for the heads up on the ARGO float 3902910 currently north of FJL.
The first image shows the drift trajectory and the cycle (report) number. The projection could be better for the arctic but Svalbard is clearly identifiable centre left, FJL under the 80N text.

The animation shows temperature and salinity charts for cycle 65,70,73 and 83-87 (latest). From my limited understanding of the charts, this float appears to have drifted along the ice front in the warm current at depth, surfacing sometimes into cold meltwater, other times into the warm current.
2 days ago SST was 2.5C salinity34.85, today -1.6C salinity 34.15

http://www.argo.ucsd.edu/How_Argo_floats.html
Quote
Argo is an international collaboration that collects high-quality temperature and salinity profiles from the upper 2000m of the ice-free global ocean and currents from intermediate depths. The data come from battery-powered autonomous floats that spend most of their life drifting at depth where they are stabilised by being neutrally buoyant at the "parking depth" pressure by having a density equal to the ambient pressure and a compressibility that is less than that of sea water. At present there are several models of profiling float used in Argo. All work in a similar fashion but differ somewhat in their design characteristics. At typically 10-day intervals, the floats pump fluid into an external bladder and rise to the surface over about 6 hours while measuring temperature and salinity. Satellites or GPS determine the position of the floats when they surface, and the floats transmit their data to the satellites. The bladder then deflates and the float returns to its original density and sinks to drift until the cycle is repeated. Floats are designed to make about 150 such cycles.

data here http://www.argodatamgt.org/Access-to-data/Description-of-all-floats2
choose 3901910

"These data were collected and made freely available by the Coriolis project and programmes that contribute to it (http://www.coriolis.eu.org)."
edit: slowed the gif a bit
« Last Edit: December 13, 2018, 10:51:43 PM by uniquorn »

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #112 on: December 16, 2018, 12:53:29 PM »
An amateur attempt to match argo float 3901910 to amsr2 to see how close to the ice edge it travelled, aug18-dec14. It reported weekly until nov30 and has reporting daily since. Report (cycle) numbers are overlayed onto Greenland, bottom left.
edit:added temp labels

Approximate data based on eyeballing the attached charts is in text below. Timing the temp/salinity data to the animation makes the gif too large. Easiest to download both gifs and step them manually for analysis. (or even better, advice from someone with netcdf skills pls)

The main observation for ice watchers is that the warm current alongside the ice front is ~2.5C at surface recently.

cycle   lat              long          temp C    sal      date
60   80.06547      5.16783      2.75      32.4      0818
61   80.20849      5.23104      5      34.45   0825
62   80.38986      4.78623      2.6      33.65   0901
63   80.48555      6.0284      4.5      34.42   0908
64   80.49247      6.82373      3.8      34.1      0915
65   80.58095      7.16061      4.3      34.1      0922
66   80.44863      8.30625      3.8      34.4      0929
67   80.43952      9.16231      4      34.75   1006
68   80.37718      7.56771      1.5      34.4      1013
69   80.51731      11.28802      0.3      34.1      1020
70   80.84061      14.77375      3      34.75   1027
71   80.85687      16.35878      1.5      34.6      1103
72   81.43671      17.30993      1.6      34.64   1110
73   81.56787      21.71607      -1.2      34.15   1117
74   81.61883      26.34895      -0.7      34.35   1124
75   81.62392      31.29192      -1.5      34.26   1201
76   81.82774      34.03102      -1.1      34.32   1202
77   82.01424      35.80637      -1.6      34.26   1203
78   82.1778      38.04842      2.5      34.82   1204
79   82.28333      39.82095      -1.6      34.23   1205
80   82.29029      39.77042      2.3      34.77   1206
81   82.28489      39.64985      1.8      34.74   1207
82   82.29791      39.56938      2.7      34.86   1208
83   82.25532      39.58456      0.8      34.61   1209
84   82.22805      39.50098      2.7      34.86   1210
85   82.20667      39.35864      2.5      34.86   1211
86   82.21352      39.10944      1.2      34.45   1212
87   82.21687      39.05996      -1.2      34.29   1213
88   82.21415      39.16856      0      34.49      1214

data here http://www.argodatamgt.org/Access-to-data/Description-of-all-floats2
choose 3901910
« Last Edit: December 16, 2018, 08:37:06 PM by uniquorn »

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #113 on: December 18, 2018, 12:05:10 PM »
The argo float must have gone back to a weekly cycle hopefully. Nothing new since 14th.
It should be down there somewhere.
Worldview, viirs, bt15n, dec18 with amsr2-uhh, dec17 inset. North of FJL, more choppy weather coming up.

Brigantine

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Re: Arctic Ocean salinity, temperature and waves
« Reply #114 on: December 19, 2018, 02:35:24 AM »
If ARGO floats suspect sea ice, they won't surface & transmit the new profile. They just save the data and transmit it next time.

Also I don't know how long the batteries will last with no sunlight.

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #115 on: December 20, 2018, 11:12:34 PM »
Thank you Brigantine.
Update on the whoi ITP buoys. ITP103-5 not drifting much. ITP107 and 109 reporting very low salinity down to ~50m nearer the gyre and 109 still reporting the thick layer of warmer water from ~50-100m with 107 and 110 possibly indicating the boundary of that layer. (will have to look more closely at the data sometime to show that)
Looking at the path of ITP109 compared to mercator model 92m temperature suggests the warm layer is from the Pacific.

whoi ITP103-110, dec20
mercator model 92m temperature, oct1-dec20 edit: should be rotated to match whoi map
mercator model 92m scale
« Last Edit: December 20, 2018, 11:31:22 PM by uniquorn »

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #116 on: December 21, 2018, 12:28:44 PM »
Using mercator 30m salinity here to show the Atlantic current in the Kara Sea. Note the old ice dipping north west of SZ. Didn't really find what I was looking for but posting it anyway for background info.
ascat, smos uni-bremen, mercator 30m salinity, oct17-dec20

johnm33

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Re: Arctic Ocean salinity, temperature and waves
« Reply #117 on: December 21, 2018, 02:58:24 PM »
I took a closer look wanting to see what was happening in the strait at the southern end, I was actually struck by the vorticity north of FJL. http://bulletin.mercator-ocean.fr/en/permalink/PSY4/animation/3/20181101/20181220/2/2

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #118 on: December 28, 2018, 12:42:13 PM »
Update on the persistent low concentration area north of Svalbard.
amsr2-uhh, aug1-dec28, contrast enhanced on rhs.

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #119 on: December 28, 2018, 11:02:24 PM »
A closer look using worldview, viirs, bt15n, dec23-28.
Low concentration area in the centre, Svalbard far right. Winds are forecast from the west for a few more days so the ice front may reach across the warm current to Svalbard again this year.  The cloud streets thickening up with the increasing temperature difference perhaps.

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #120 on: December 30, 2018, 05:56:16 PM »
Laptev Sea, amsr2-uhh default and high contrast, oct23-dec29.
Using Mercator 34m salinity here to compare with the underlying current from the atlantic.
salinity scale same as above

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #121 on: January 01, 2019, 06:52:31 PM »
It's been a quiet couple of months on the north Greenland coast compared to the last 4 years. Here we are looking for signs of upwelling by increasing contrast to highlight low concentration on amsr2-uhh. Wind driven 'lift off' of ice from the coast is apparent in 2014, 2016 and 2017 but no conclusive evidence of increased upwelling this year.
amsr2-uhh, nov11-dec31, 2014-2018.
days are not quite synchronised due to missing some missing data

edit: Today's worldview image of nth greenland for comparison https://tinyurl.com/ydxhk7sc
« Last Edit: January 01, 2019, 07:33:39 PM by uniquorn »

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #122 on: January 05, 2019, 04:31:03 PM »
Polarview image north west of Svalbard jan5 showing some of the area of warm atlantic water upwelling and what may be evidence of surface currents.

Nullschool version of surface currents jan5.

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #123 on: January 06, 2019, 10:53:37 AM »
Update on the whoi ITP buoys. http://www.whoi.edu/page.do?pid=163197
ITP103 showing a steady increase in salinity at depth
ITP104 showing a steady increase in salinity at depth (recent data may smooth out)
ITP105 no profile since jan2. Dec31 profile showed a lesser increase in salinity at depth
ITP107 decrease in salinity to ~50m confirming gyre
ITP109 decrease in salinity to ~50m confirming gyre. 50m-100m warm layer
ITP110 confirming 50m-100m warm layer

edit:no further reports from the argo float yet
« Last Edit: January 06, 2019, 11:20:54 AM by uniquorn »

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #124 on: January 09, 2019, 11:32:50 AM »
Atlantic current beneath the ice on it's way to the Laptev.
Worldview, viirs,bt15,night,jan7-9.
Mercator 34m salinity, jan7

edit: polarview image, jan11 for future reference.
« Last Edit: January 11, 2019, 12:28:40 PM by uniquorn »

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #125 on: January 15, 2019, 12:58:58 PM »
The warm current north of Svalbard dominates the ice on the atlantic front despite the cold winds from the SSW. Cloud streams highlight the temperature difference (estimates: air ~-30C, water ~2C) and wind direction. Acceleration of ice towards the Fram Strait opening up the already numerous fractures all the way to the Lincoln sea.

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #126 on: January 17, 2019, 12:57:12 PM »
Using mercator 0m salinity compared with amsr2-uhh sea ice concentration here to show possible upwelling of warmer water along the canada/alaska coast. Nov17-jan16
« Last Edit: January 18, 2019, 04:02:49 PM by uniquorn »

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #127 on: January 18, 2019, 04:08:18 PM »
Update on DMI polar portal ice surface temperature, nov1-jan16.

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #128 on: January 18, 2019, 05:07:33 PM »
Update on the whoi ITP buoys. http://www.whoi.edu/page.do?pid=163197
ITP103 still showing an increase in salinity at depth
ITP104 little change
ITP105 is reporting again :)  The data may need smoothing.
Both 104 and 105, most northerly, are drifting  further north against the annual drift.
ITP107 decrease in salinity to >50m confirming gyre
ITP109 decrease in salinity to ~50m confirming gyre. 50m-100m warm layer
ITP110 confirming 50m-100m warm layer

argo float 3901910 state is inactive  :(

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #129 on: January 23, 2019, 09:57:47 PM »
quick update on whoi itp107 which may have reached the outer extent of the gyre or some other event.
Sharp increase in salinity close to surface.
Not sure about the rest till it settles down.
click for full size

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #130 on: January 23, 2019, 11:15:13 PM »
Adding my theory that belongs to me about the Lincoln sea here, updated to jan23. (but it could be the super blood wolf full moon)
Worldview, viirs, bt15n, jan14-23 with NOAA bathymetry map.
will it go beyond the channel?
« Last Edit: January 24, 2019, 12:29:56 AM by uniquorn »

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #131 on: January 24, 2019, 12:41:25 PM »
Using mercator salinity at 0m and 30m here to show current as the temperature gradient isn't enough to give much detail. Atlantic water flows south along the Lomonosov Ridge line and then has to circumvent Greenland.
The Mercator model appears to be somewhat validated by the recent ice movement in the Lincoln sea. Note the increase in salinity (and possibly temperature) entering and exiting the Nares Strait, probably from deeper water.
The indications are that warmer saltier water, some of it from much deeper than 30m, flowing into the shallower Lincoln Sea is weakening the ice and taking it into the Nares.

Mercator salinity 0m and 34m, dec1-jan23, every 3days
added today's worldview image.  https://go.nasa.gov/2UbWItX

edit: except that everything about that image suggests current from the pacific side of Lomonosov.
« Last Edit: January 24, 2019, 08:45:09 PM by uniquorn »

uniquorn

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uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #133 on: January 27, 2019, 09:54:04 PM »
Off topic but testing ascat interferometry (A-team) here as it's 10MB. Showing december as well as it's more interesting pre SSW. Surprised that the line north of Greenland showed up (from quite early on) so it probably is low concentration ice that moves more than the ice surrounding it.
The old ice line is pretty clear too so may be useful for tracking over longer time frame.
3 days difference so the last 3 dates are invalid.
ascat interferometry(A-Team) 2018343-2019023
« Last Edit: January 27, 2019, 10:04:32 PM by uniquorn »

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #134 on: January 28, 2019, 06:00:03 PM »
Mercator current 92m, jan2018-jan2019 for reference.
I didn't realise how strong the current from Kara to Laptev is.
ITP107 confirming turbulence north of utqiagvik (barrow)
whoi ITP103-110, jan28

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #135 on: January 29, 2019, 07:49:18 PM »
Tracked the north Greenland dark line back to nov17 using worldview viirs brightness temperature (band15)night. Posting here as it's 6MB. There are many other parallel fractures heading towards the Fram Strait and some larger ones out of crop on the Beaufort side of the Lomonosov. Possible they are related to the ridge. I don't know why this one stands out so clearly.
With a clear line to focus on, it looks like a lot of ice melted and exported.
« Last Edit: January 29, 2019, 07:57:32 PM by uniquorn »

Shared Humanity

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Re: Arctic Ocean salinity, temperature and waves
« Reply #136 on: January 29, 2019, 08:48:55 PM »
Tracked the north Greenland dark line back to nov17 using worldview viirs brightness temperature (band15)night. Posting here as it's 6MB. There are many other parallel fractures heading towards the Fram Strait and some larger ones out of crop on the Beaufort side of the Lomonosov. Possible they are related to the ridge. I don't know why this one stands out so clearly.
With a clear line to focus on, it looks like a lot of ice melted and exported.

When you look at how much ice has moved towards the Barents, it is amazing how little ice is there.

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Re: Arctic Ocean salinity, temperature and waves
« Reply #137 on: January 31, 2019, 12:40:43 PM »
In previous years I've been intrigued by the persistent upwellings in the Beaufort say around 150/76 this year although there are signs of them on the salinity animation none on the lead opening animation. though there are signs of persistent internal waves emanating from the Pacific[?].
So I took a look at the compressive strength animation where they [IWs] are far more obvious, there's also an interesting sheer line caused by the rotating pack, springing from Prince Patrick island and close enough to suggest it's following the contours of the Canadian basin.
Finally looking at the Ice thickness animation it seems the tides in Amundsen are forcing the ice to rotate much faster than in previous years, perhaps it's moving too fast for the upwellings to make an impact on the surface.
I've left the links to the animations because sometimes I 'get' more watching the animation develop.

uniquorn

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Re: Arctic Ocean salinity, temperature and waves
« Reply #138 on: January 31, 2019, 08:32:22 PM »
Thanks johnm33, some new things (for me) to look into.
A nice intro to internal waves from whoi here https://www.whoi.edu/oceanus/feature/the-waves-within-the-waves

johnm33

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Re: Arctic Ocean salinity, temperature and waves
« Reply #139 on: January 31, 2019, 11:51:21 PM »
Welcome, the 'Importance of Waves' thread has some good links too, which may be of interest, plus a variety of views.

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Re: Arctic Ocean salinity, temperature and waves
« Reply #140 on: February 02, 2019, 03:53:20 PM »
Nice thread. Any comments on this? ascat day28-32 (middle of the new dark ice)
It matches the compressive strength map pretty well, but what causes it?
edit: went back 50 days. Looks like it may be moon related.
« Last Edit: February 02, 2019, 07:44:26 PM by uniquorn »

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Re: Arctic Ocean salinity, temperature and waves
« Reply #141 on: February 02, 2019, 10:35:44 PM »
"Any comments" Still thinking, but the presistent high [slp] over the Arctic in january would cause some drop in overall sea level, then we have a significant low in Bering which would force tides a little higher. So maybe some Pacific water forced in pulses through the strait, that and some other factor, the thickest ice surged back rather than following it's usual [recent] trajectory towards Amundsen. It may be the other factor was a surge of Atlantic water falling out of St Anna trough creating a pressure wave against Greenland, accelerating the flows through Fram and Nares, once forced those currents would suck more water in their wake.
The ingress of Pacific water has caused some warming, if it was anywhere near as warm as the Atlantic we could see some serious evaporation. As it is we may see it break open some leads towards McKenzie once the new moon gets Amundsen pumping again in the next few days.
 The sheer line may be the result of a returning/reflected wave meeting the incoming but why would it be straight?
« Last Edit: February 02, 2019, 10:42:17 PM by johnm33 »

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Re: Arctic Ocean salinity, temperature and waves
« Reply #142 on: February 03, 2019, 12:19:06 AM »
Maybe it's related to the shear in the thicker ice on the edge of the Chukchi. Will try to tease out more detail tomorrow.

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Re: Arctic Ocean salinity, temperature and waves
« Reply #143 on: February 03, 2019, 12:29:12 PM »
If the waves are carried by the salinty layer that straddles 100m depth, then perhaps that layer is rotating faster than those below. Then the sheer  could be caused by a reaction between the incoming waves and any vortices induced on the northern 'front' of that rotating layer, in some sense the waves may be accelerated beyond coherence by there own accumulating torque as they approach the axis of rotation, and their energy added to that of the vortices present. ?
I'm gong to look back over the buoy data to see if anything shows there.

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Re: Arctic Ocean salinity, temperature and waves
« Reply #144 on: February 03, 2019, 03:59:53 PM »
Not sure that layer reaches so far but it's an idea. Did my best with an enlarged version.
ascat day15-33
« Last Edit: February 03, 2019, 04:06:06 PM by uniquorn »

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Re: Arctic Ocean salinity, temperature and waves
« Reply #145 on: February 04, 2019, 09:19:27 PM »
Verifying with worldview viirsbt15n, jan21-feb3. Could be a combination of waves as there are parallel fractures both sides.
« Last Edit: February 04, 2019, 09:24:35 PM by uniquorn »

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Re: Arctic Ocean salinity, temperature and waves
« Reply #146 on: February 04, 2019, 11:26:47 PM »
Mercator does have a large salinity difference along that line at 0m, almost parallel with another further north. Similar at 34m. Could it be a thrust into the less dense water, sending a wave northwards, possibly reflecting back?
mercator 0m salinity, dec20-feb3

update on ITP103-110, feb4
« Last Edit: February 05, 2019, 12:00:14 AM by uniquorn »

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Re: Arctic Ocean salinity, temperature and waves
« Reply #147 on: February 05, 2019, 12:19:19 AM »
That looks like Atlantification spreading from the CAA, surprising. A different salinity would affect the rate of propagation. I'm still not sure what caused the waves, too many over a short period to simply be tidal, the sheer line may be the northern front of the gyre. I'm not even certain what layer the waves are in.
 Take a look at this, zoom in and decide if the twists in the waves are artifacts or real, then I have to wonder if the persistent grid perpendicular to the sheer could be real too, neither are common features.
I'd assumed the saline layer that straddles 100m reached to Lomonosov, it looks more likely that it's continuous over all the Arctics basins. 
Have to admit I'm baffled, as usual, about what goes on beneath the ice.

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Re: Arctic Ocean salinity, temperature and waves
« Reply #148 on: February 05, 2019, 06:48:34 PM »
Animated compressive strength charts to see how they match up (with post 144), jan27-feb4.


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Re: Arctic Ocean salinity, temperature and waves
« Reply #149 on: February 05, 2019, 06:52:41 PM »
Looking back through ascat to 2010 there are lots of surges but only one similar, less obvious, event in 2014, day 98-109. Anecdotally, the pack appears less mobile in previous years. Not sure how to quantify that.