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Messages - uniquorn

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51
Arctic sea ice / Re: What the Buoys are telling
« on: October 05, 2020, 09:36:13 PM »
buoys north of 45N, apr-oct. Best viewed at half speed.
moved to test space

52
Arctic sea ice / Re: What the Buoys are telling
« on: October 03, 2020, 11:06:09 PM »
iabp drift update
whoi buoys not updated again

53
Arctic sea ice / Re: 2020 Sea ice area and extent data
« on: October 03, 2020, 01:42:40 PM »
Wipneus' Central Arctic Basin extent has recently been creeping beyond the limit set by 2012.
data to sep30
cryosphere today regional map

54
Arctic sea ice / Re: Arctic Ocean salinity, temperature and waves
« on: October 03, 2020, 01:34:08 PM »
It's not just the salinity, Atlantic water returning from the Arctic Ocean is also cooler with higher density.

Key Physical Variables in the Ocean: Temperature, Salinity, and Density


Quote
Figure 1: A vertical profile of temperature and salinity at 39°N, 152°W in the North Pacific (data courtesy of the CLIVAR and Carbon Hydrographic Data Office, cchdo.uscd.edu).
a) Vertical profiles of in-situ temperature t, potential temperature θ, and Conservative Temperature Θ. Inset shows an expanded view of deep ocean values. Potential and Conservative temperature are within 0.0003°C in the deep ocean. Note that heat content (proportional to Θ) actually decreases with depth, but pressure effects cause a rise in the in-situ temperature t. b) Vertical profiles of Practical Salinity SP (with no units), Reference Salinity SR, and Absolute Salinity SA. c) Vertical profiles of in-situ density (σ), potential density referenced to the sea surface (σθ), and potential density referenced to 4000 dbar (σ4). Most of the in-situ density increase with depth is due to pressure effects, which are removed in the calculation of potential densities, showing how weakly stratified the ocean actually is.
© 2013 Nature Education All rights reserved. View Terms of Use

or a simpler way of looking at it, though not that relevant to the arctic.

Also an 'interesting' section of itp110 drift path showing how density changes with temperature and salinity, 7m-80m from 2019, day123-218 (best viewed at half speed)
density green, temperature purple, salinity red
temp    -1.8 to 0.6C
salinity  27.5 to 31.2
density 1021.5 to 1025kg/m^3

http://www.csgnetwork.com/water_density_calculator.html
Quote
The equation used in this calculator can be found in:
Millero, F, C. Chen, A Bradshaw, and K. Schleicher, 1980: A new high pressure equation of state for seawater, Deep Sea Research, Part A, 27, 255-264.
doi:10.1080/15210608209379435

It would be nice to have someone else check the calculations:
Quote
function CalcDen(form) {
//function sig=sigma(p,t,s)

// calculates in situ density.
// millero et al 1980, deep-sea res.,27a,255-264
// jpots ninth report 1978,tenth report 1980
// units:
//       pressure        p        decibars
//       temperature     t        deg celsius (ipts-68)
//       salinity        s        nsu (ipss-78)
//                       sigma    (10.**-3)g/cm**3
//
// r. schlitzer  (5/18/89)


var p = document.denform.pressure.value;
var t = document.denform.temp.value;
var s = document.denform.conc.value;
// change pressure from input units of decibars to bars
// square root salinity.
p=p/10;sr= Math.sqrt(Math.abs(s));
// density pure water at atm press in kg/m3 = (10**-3)gm/cm3
r1=((((6.536332e-9*t-1.120083e-6)*t+1.001685e-4)*t-9.095290e-3)*t+6.793952e-2)*t- .157406;
// seawater density atm press.
r2=(((5.3875e-9*t-8.2467e-7)*t+7.6438e-5)*t-4.0899e-3)*t+0.824493;
r3=(-1.6546e-6*t+1.0227e-4)*t-5.72466e-3; r4=4.8314e-4;
sig=(r4*s + r3*sr + r2)*s + r1;
// compute compression terms
e=(9.1697e-10*t+2.0816e-8)*t-9.9348e-7;
bw=(5.2787e-8*t-6.12293e-6)*t+8.50935e-5; b=bw+e*s;
c=(-1.6078e-6*t-1.0981e-5)*t+2.2838e-3;
aw=((-5.77905e-7*t+1.16092e-4)*t+1.43713e-3)*t+3.239908;
a=(1.91075e-4*sr+c)*s+aw;
b1=(-5.3009e-4*t+1.6483e-2)*t+7.944e-2;
a1=((-6.1670e-5*t+1.09987e-2)*t-0.603459)*t+54.6746;
kw=(((-5.155288e-5*t+1.360477e-2)*t-2.327105)*t+148.4206)*t+19652.21;
k0=(b1*sr+a1)*s+kw;
// evaluate pressure polynomial and return
k=(b*p+a)*p+k0;
sig=(k*sig+1000*p)/(k-p);
// sig remains unchanged since is (10**-3)gm/cm**3
document.denform.density.value = perRound(sig+1000);
}

55
Arctic sea ice / Re: Arctic Ocean salinity, temperature and waves
« on: October 02, 2020, 05:21:52 PM »
Nice. Underwater waterfalls.

56
Developers Corner / Re: Test space
« on: October 02, 2020, 01:07:03 AM »
finally starting to get my head around macid's code for this
will probably have to be mp4. Maybe possible to label the years. Cairo might fix the colours or work out how to make them discrete.

edit: whoi itp7,8 and 9 produced over 9million variable and took 6hrs to load so looking at loading them into MySQL and querying from there. I wonder what computer macid was using.

57
Arctic sea ice / Re: The 2020/2021 freezing season
« on: October 01, 2020, 04:36:51 PM »
Up to sep29 this year, 2012 still defines the worst case scenario for Wipneus' CAB

58
Arctic sea ice / Re: Home brew AMSR2 extent & area calculation
« on: October 01, 2020, 01:59:18 PM »
daily ImageJ pixel count on v103, sep4-30. Might be interesting to run it on Beaufort tail only

59
Arctic sea ice / Re: What the Buoys are telling
« on: September 29, 2020, 11:39:16 PM »
iabp buoy drift update, 5days. I think this will be the size, just need to think about the crop.
itp120 and 121 not on iabp yet

drift speeds of the first 5 buoys

60
Arctic sea ice / Re: What the Buoys are telling
« on: September 29, 2020, 12:56:27 PM »
T78 and T81 temperature charts at ~89.3N today

61
Arctic sea ice / Re: The 2020 melting season
« on: September 29, 2020, 12:15:08 PM »
It's a fair question but for me also it is too early to come to a conclusion. Too much movement and not enough data. Next analysis will be yearly paths with 50m temperature to see what that shows. It's likely to be warm pacific incoming from the Chukchi plateau as there is no rough topography at ~78N-140. Maybe the buoys will show us how 'wide' the warmer area is. Mercator at 34m and 92m depth misses the peak. Maybe Aslan can help with that.

OTG has plenty of suggestions ;)

edit: latest data from itp121 is a bit cooler at 50m

%ITP 121, profile 18: year day longitude(E+) latitude(N+) ndepths
2020  273.25141  -138.1066  77.2762  375
2020  273.25303   44   -0.0354   30.0949
2020  273.25311   46    0.3879   30.2224
2020  273.25319   48    0.4206   30.3668
2020  273.25328   50    0.4183   30.5225
2020  273.25336   52    0.2941   30.6820
2020  273.25345   54    0.5035   30.8875
2020  273.25353   56    0.5986   31.0057
2020  273.25361   58    0.5534   31.1116
2020  273.25369   60    0.6788   31.2080
2020  273.25377   62    0.7504   31.2909
2020  273.25385   64    0.9152   31.3495
2020  273.25394   66    0.8092   31.3845
2020  273.25403   68    0.6351   31.4414
2020  273.25411   70    0.3613   31.5064
2020  273.25419   72    0.2022   31.5450
2020  273.25427   74    0.0279   31.5973
2020  273.25435   76   -0.0417   31.6361

62
Arctic sea ice / Re: The 2020 melting season
« on: September 29, 2020, 01:53:33 AM »
2020, 2018, 2015, 2012, and 2009. Roughly the same days, similar location.
Conclusion?
More people should assess the data.

63
Arctic sea ice / Re: What the Buoys are telling
« on: September 29, 2020, 12:40:04 AM »
great. Thanks to Ignatius and Wendy, WHOI itp buoys are back on IABP. So here is a larger presentation showing overview and close up. It's one day shorter to keep file size down. This is probably close enough to show inertial oscillations. A bit like osi-saf on steroids.
itp103 looks very straight
updated below

64
Arctic sea ice / Re: The 2020 melting season
« on: September 29, 2020, 12:26:22 AM »
itp121 is here     https://www.whoi.edu/page.do?pid=166917
The older buoys can be found in completed missions. whoi provide a .dat file for each profile. I load them all and make a chart for each profile using octave in this case. I haven't converted it to R yet.

Every profile will make a nice chart in excel or open source libreoffice if the first 2 lines are removed (then space as separator) so a day273 comparison shouldn't be too arduous. The biggest step is downloading the data and actually looking at it. It's only a text file labelled as .dat
Quote
is there an easy way
maybe.
download and install notepad++
Download the buoy .zip file (I have to right click and open in new tab)
extract all
right click on one .dat profile and open in Notepad++
delete the first 2 lines
save as test.csv
open in excel with 'space' as separator
make chart


65
Walking the walk / Re: Gardening
« on: September 28, 2020, 11:37:45 PM »
Vetch is cheap too.

Some feedback on planting potatoes in shredded/chipped wood. We got a good crop from the plants at the edge of the mulch. I think it was too deep in the middle and only half of the potatoes made it to the surface. However the yield was similar to another bed we planted under 15cm of hay topped up with grass cuttings.
Another possible upside is that even after recent heavy rain, the potatoes under woodchip and grass cuttings are still quite dry so it looks like we can keep them in the ground a bit longer. Some that we stored have already started chitting so I planted them (beneath the ground for once) to see what happens over winter. Also put in some very early garlic as a test.


66
Arctic sea ice / Re: MOSAiC news
« on: September 28, 2020, 10:02:40 PM »
  Lat  Long  YY-MM-DD  UTC     Wind       T(C)  N  h  VV  wwWW  ICE  Pnn(hPa)
  82.9   22.6 20-09-28 18:00    6  300     -8.1  8  5  93  4842 52/91 1012.1

48 -- fog, depositing rime, sky visible

Wispy bow radar

PS in pancake ice

67
Arctic sea ice / Re: The 2020 melting season
« on: September 28, 2020, 09:44:17 PM »
2020, 2018, 2015, 2012, and 2009. Roughly the same days, similar location.

68
Arctic sea ice / Re: The 2020 melting season
« on: September 28, 2020, 12:08:30 PM »
whoi itp33 was deployed in 2009 in a similar location to itp121 but 15 days later. The animation compares the first 16 profiles.
In that location the salinity gradient was steeper in 2009, temperature was clearly much, much lower.
Depending on itp121's future drift path, this could be a combination to follow further.

69
Arctic sea ice / Re: What the Buoys are telling
« on: September 27, 2020, 11:23:55 PM »
Ignatius Rigor from the IABP talks about testing buoy sensors and buoy deployment.
http://www.apl.washington.edu/project/project.php?id=arctic_buoys


70
Arctic sea ice / Re: The 2020 melting season
« on: September 27, 2020, 10:26:21 PM »
Occasional sharp peaks above 2C are not uncommon at 50m in the Beaufort over the last year but you have a point, today's broader peak at 48m-56m on itp121 does look significant. I would wait a few days before claiming that the halocline is bust though, particularly at the beginning of the freezing season.

%ITP 121, profile 13: year day longitude(E+) latitude(N+) ndepths
2020  271.00141  -138.6742  77.2639  374
%year day pressure(dbar) temperature(C) salinity
<>
2020  271.03226   42   -1.0367   29.9797
2020  271.03216   44    0.3501   30.0927
2020  271.03207   46    1.5122   30.3881
2020  271.03199   48    2.0639   30.5199
2020  271.03191   50    2.2932   30.6454
2020  271.03182   52    2.2169   30.7789
2020  271.03172   54    2.1873   30.8761
2020  271.03163   56    2.0021   30.9866
2020  271.03154   58    1.6610   31.0456
2020  271.03146   60    1.6165   31.1104
2020  271.03138   62    1.5137   31.1871
2020  271.03128   64    1.2485   31.2670
2020  271.03119   66    1.1310   31.3255
<>
Quote
And it's now centered at under 50m depth. Used to be over twice as deep.
I don't think so. The composite plots overwrite many of the profiles. I find it more useful to look at them individually as an animation. Beaufort peaks are normally at 50-70m imho. Maybe I will have time to run some older buoy profiles for comparison.

71
Arctic sea ice / Re: What the Buoys are telling
« on: September 27, 2020, 01:17:03 PM »
experimental large presentation of the last 6days of iabp buoys showing overview and close up (by zooming and scrolling). whoi itp buoys haven't updated on iabp since sep21.
updated below

72
Arctic sea ice / Re: The 2020 melting season
« on: September 27, 2020, 12:22:44 PM »
Nice charts but I don't agree with the interpretation. The halocline doesn't appear to be bust yet.
Data shown starts at 7m depth.
The halocline in that location looks similar to previous years. Beaufort temperatures at 50m depth are a concern for the future that have been well noted on this thread and others.

@interstitial - more thickness data
SIMB  https://www.cryosphereinnovation.com/443910  (no charts yet. edit: working with chrome, not firefox)
Quote
ITP120 was deployed on a 1.15 m ice floe in the Beaufort Sea on September 21, 2020 at 78° 54.0 N, 142° 21.2 W as part of the Beaufort Gyre Observing System (BGOS) during the JOIS 2020 cruise on the CCGS Louis S. St. Laurent. On the same icefloe, a US Army Cold Regions Research and Engineering Laboratory (CRREL) Seasonal Ice Mass Balance Buoy 3 was also installed. The ITP is operating on a standard sampling schedule of 2 one-way profiles between 7 and 760 m depth each day.
SIMB  https://www.cryosphereinnovation.com/441910
Quote
ITP121 was deployed on a 2.3 m ice floe in the Beaufort Sea on September 20, 2020 at 77° 22.3 N, 137° 16.4 W as part of the Beaufort Gyre Observing System (BGOS) during the JOIS 2020 cruise on the CCGS Louis S. St. Laurent. On the same icefloe, a US Army Cold Regions Research and Engineering Laboratory (CRREL) Seasonal Ice Mass Balance Buoy 3 was also installed. The ITP is operating on a standard sampling schedule of 2 one-way profiles between 7 and 760 m depth each day and includes a fixed SAMI PCO2 with PAR and SBE-37 microcat with dissolved oxygen at 6 m depth.

Added whoi itp121 microcat1 at 5m depth

73
Arctic sea ice / Re: What the Buoys are telling
« on: September 26, 2020, 05:27:25 PM »

74
Arctic sea ice / Re: What the Buoys are telling
« on: September 26, 2020, 03:12:36 PM »
Mosaic T78 and T81 at 89.6N both almost flatlining again at ocean temperature.

75
Arctic sea ice / Re: Arctic Ocean salinity, temperature and waves
« on: September 25, 2020, 12:01:58 PM »
Images of the area of 'flash freezing' in the Beaufort.
Worldview terra modis true colour (adaptive contrast) with amsr2-awi-v103 overlay
Polarview S1B with worldview true colour overlay (click)
A cropped comparison of 2 small areas of interest.

76
Developers Corner / Re: Test space
« on: September 24, 2020, 10:10:09 PM »
155 arctic buoys, mar-sep

77
Arctic sea ice / Re: MOSAiC news
« on: September 24, 2020, 12:51:30 PM »
@interstitial - Many of the new buoys have thickness and some additional information like 'placed on ridge' listed under buoy info here

78
Arctic sea ice / Re: MOSAiC news
« on: September 24, 2020, 12:24:28 PM »
  Lat  Long  YY-MM-DD  UTC     Wind       T(C)  N  h  VV  wwWW  ICE  Pnn(hPa)
  86.0   59.5 20-09-24 09:00    8  130     -0.3  8  2  96  7872 57/9/  985.1
  86.0   59.5 20-09-24 08:00    8  120     -0.6  /  /  //  //// /////  985.5
  86.0   59.5 20-09-24 07:00    9  120     -0.4  /  /  //  //// /////  986.1
  86.0   59.5 20-09-24 06:00    9  120     -0.4  8  1  94  1052 57/9/  986.9
  86.0   59.5 20-09-24 05:00    9  110     -0.4  /  /  //  //// /////  987.8
  86.0   59.5 20-09-24 04:00   10  110     -0.4  /  /  //  //// /////  988.5
  86.0   61.4 20-09-24 02:00   10  110     -0.3  /  /  //  //// /////  990.1


edit: jp2 (some gamma alteration)
overview with rough PS location highlighted

79
Arctic sea ice / Re: Arctic Ocean salinity, temperature and waves
« on: September 23, 2020, 11:54:58 PM »
Thanks for those articles.

2 new whoi itp buoys, 120 and 121

80
Arctic sea ice / Re: MOSAiC news
« on: September 23, 2020, 11:51:29 PM »
I think you mean just north of 86 north old boy?
aye aye capn, merci
Should have mentioned wind at 75km/hr
86.1N   88.0 20-09-23 00:00   21(m/s)

81
tbuoy update. The quick 'refreeze' on T78 might be the porous layer at the bottom cooling.

82
Arctic sea ice / Re: Home brew AMSR2 extent & area calculation
« on: September 23, 2020, 02:38:54 PM »
v103  daily pixel count shows the return of the possible harmonic at 50% concentration. 0% tending to agree with the jaxa minimum extent.

I wonder if seaice.de might comment on amsr2 representation of the Beaufort Sea recently. Was it perhaps freezing rain showing up more noticably over open water? Air temps of ~-2C on sep17 according to nullschool gfs

Worldview terra modis with amsr2-uhh inset, sep17
Beaufort, v103, sep4-22

83
Arctic sea ice / Re: MOSAiC news
« on: September 23, 2020, 11:28:22 AM »
No interest in snow then ;)

PS just north of 80N 86N on Polarview S1B at 03:19 this morning, track history from sailwx
weather at the moment
24 -- freezing rain
-0.2C
ice:
5 -- Very close pack ice 7/8 to < 8/8 concentration
5 -- All thin first-year ice (30-70 cm thick)
yesterday's fomo pic.

84
Arctic sea ice / Re: The caa-greenland mega crack
« on: September 23, 2020, 11:11:46 AM »
amsr2-awi-v103, caa, sep4-22 (PM)
click for clarity and motion

85
Arctic sea ice / Re: Arctic Ocean salinity, temperature and waves
« on: September 22, 2020, 02:23:37 PM »
Overview of available iabp buoys north of Greenland and a closer animation of 300234065497190, 300234068810610 and 300234068027940.
csv data attached as text.

https://betterexplained.com/articles/an-interactive-guide-to-the-fourier-transform/

86
Arctic sea ice / Re: The 2020 melting season
« on: September 22, 2020, 02:12:06 PM »
Quote
Arctic sea ice decline stalls out at second lowest minimum

Strange title.

87
Arctic sea ice / Re: MOSAiC news
« on: September 22, 2020, 10:45:22 AM »
Any volunteers to keep an eye on a new snow buoy, 2020S98, close the the pole?

Also 2020S106, 2020S107 and Also 2020S108
The ever improving meereisportal makes it visually simple.

For latest lat/lon it is still necessary to look at the data tables.
meereisportal here

or the iabp daily table here
though you need to know the buoyID
for example
  300234066087160   NA   2020   Snow_Buoy   AWI
   MOSAiC   09/21/2020   89.16   109.45

88
Arctic sea ice / Re: Arctic Ocean salinity, temperature and waves
« on: September 21, 2020, 10:29:13 PM »
Overview of iabp buoys, will be taking a closer look at some of them tomorrow

89
Arctic sea ice / Re: Arctic Ocean salinity, temperature and waves
« on: September 21, 2020, 08:46:01 PM »
Thanks to u300673 for this great article from 2012
Sea ice inertial oscillations in the Arctic Basin
F. Gimbert, D. Marsan, J. Weiss, N. C. Jourdain, and B. Barnier
https://tc.copernicus.org/articles/6/1187/2012/tc-6-1187-2012.pdf
Quote
As observed from buoy drift data, the sea ice  mean  speed  over  the  Arctic  increased  at  a  rate  of  9% per decade from 1979 to 2007, whereas the mean deformation rate increased by more than 50 % per decade over the same period (Rampal et al.,2009). These two aspects of recent sea ice evolution, i.e. strong decline in terms of ice extent and thickness, and accelerated kinematics, are strongly coupled within the albedo feedback loop. Increasing deformation means increasing fracturing, hence more lead opening and a decreasing albedo (Zhang et al.,2000). As a result, ocean warming, in turn, favours sea ice thinning in summer  and  delays  refreezing  in  early  winter,  i.e.  strengthens sea ice decline. This thinning should decrease the mechanical strength, therefore allowing even more fracturing, hence larger speed and deformation. A consequence is the acceleration of the export of sea ice through Fram Strait, with a significant impact on sea ice mass balance (Rampal et al.,2009,2011; Haas et al.,2008), and ice age (Nghiem et al.,2007). Moreover, sea ice mechanical weakening decreases the likelihood of arch formation along Nares Strait, therefore allowing old, thick ice to be exported through this strait (Kwok et al.,2010).

90
Arctic sea ice / Re: MOSAiC news
« on: September 21, 2020, 08:17:44 PM »
<>has uniqorn been showing us animations of tidal oscillation or inertial oscillation? And does that mean that there is no (or at the very most negligible) tidal movement in the Arctic?
You may be right binntho. The drift paths from the F Gimbert paper look very similar to the buoy animations except for a larger possible component of inertial oscillation this year. The maths is above my pay grade also but I may work up to it in time. I think tides have a part to play in the arctic, more importantly at the shelf breaks. An increase in inertial oscillation due to thinning and fractured ice cover adds another (previously unknown to me) feedback loop that deserves more consideration from the forum.

Also shown is P163 drift speed. Calculating the time between 12 peaks in the centre gave an average of 23.29hrs/peak which is too short for a lunar cycle so I'm open to other explanations.
P163
09 06 2200 to 09 12 1330
279.5hours, 12peaks = 23.29hrs/peak

I may take a look at north Atlantic buoys on another thread though a comparison of some in the central arctic from previous years would be more interesting. Meanwhile here are some of the remaining Mosaic buoys in the Greenland Sea. awi amsr2 inset to show rough ice location. (graticule belongs to the animation)


91
Arctic sea ice / Re: Arctic Ocean salinity, temperature and waves
« on: September 20, 2020, 11:14:07 PM »
I hoped dissolved oxygen on 117 might mean more to you than it does to me. Actually it could be a battery problem, it has been going for a year.

92
Arctic sea ice / Re: Arctic Ocean salinity, temperature and waves
« on: September 20, 2020, 09:42:39 PM »

93
Arctic sea ice / Re: MOSAiC news
« on: September 20, 2020, 09:11:14 PM »
drift update from P176.
2 submarine landslides a day seems unlikely. I think I'll stick with tides.
Absolutely (grrmble grrmble) and the gif is fantastic, almost like a Micky Mouse picture.<snippage>
No update from meereisportal buoys today.
Now, how to identify an inertial oscillation ice drift component, a tidal ice drift component and a wind driven ice drift component?
Note that the more northerly mickey mouse is flatter than the others.
For each buoy, You could use a plane x,y (coordinates in your plot for instance) instead of lat lon to avoid arctifacts for being so close to the pole, then FFT the x and y components, get amplitude and phase for different frequencies and isolate translation and different modes of oscillation (x and y in phase or 180) or rotation (x and y in +/- 90 deg phase) in the 2D plane.
The wind drift won’t have a frequency in resonance with Earth rotation frequency (day)
ok. You seem to know how to do it. Here is gif of latest movement with data as txt. x and y are lon.utm and lat.utm. Let me know if you need anything else.

94
Arctic sea ice / Re: MOSAiC news
« on: September 20, 2020, 07:28:34 PM »
PS heading south, sailwx
updated

95
Arctic sea ice / Re: MOSAiC news
« on: September 20, 2020, 03:08:40 PM »
drift update from P176.
2 submarine landslides a day seems unlikely. I think I'll stick with tides.
Absolutely (grrmble grrmble) and the gif is fantastic, almost like a Micky Mouse picture.<snippage>
No update from meereisportal buoys today.
Now, how to identify an inertial oscillation ice drift component, a tidal ice drift component and a wind driven ice drift component?
Note that the more northerly mickey mouse is flatter than the others.

96
Arctic sea ice / Re: The caa-greenland mega crack
« on: September 19, 2020, 11:19:53 PM »
as the sunlight fades, https://go.nasa.gov/2FKBrpB

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tbuoy update

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Arctic sea ice / Re: Arctic Ocean salinity, temperature and waves
« on: September 19, 2020, 10:38:32 PM »
@Bruce Steele, whoi itp117 temperature spike on SAMI
edit: similar spike on itp105, Mackenzie river water?

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Arctic sea ice / Re: Arctic Ocean salinity, temperature and waves
« on: September 19, 2020, 09:58:07 PM »
mosaic iabp buoy names and relative locations for ref

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Arctic sea ice / Re: MOSAiC news
« on: September 19, 2020, 05:53:55 PM »

EDIT: The speed of drift swings between 10% and 20% of normal walking speed. And the tidal swings are only a few hundred meters each way. The circular movement I guess has more to do with changing wind direction than anything else.

Great. As you guessed that one hopefully you will run the numbers to prove it. Hourly wind direction from PS is here   P169 is near if you need buoy data.
I suspect it is the combination of both since wind drift appears to be of the same order of magnitude as 'tidal drift' and it's a more likely explanation than continuous tight wind vortexes at multiples of walking speed. 

Here attempting to overlay the tight group of buoys onto bow radar. Maybe they are either side of a fault line or along a ridge. click for animation.

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