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uniquorn

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Re: MOSAiC news
« Reply #350 on: December 01, 2019, 04:07:01 PM »
drift update, 3 Pbuoys closest to PS, ~9days in 100frames.
This ani includes an estimate of PS location based on 10/17 distance between p201 and p207. Some coordinates taken from polarview images have been added in red to verify the rough path. The timing of the path passing close to the polarview points still needs to be verified.
Tech  note: PS points in red taken from a list collated by A-Team using the method here
« Last Edit: December 01, 2019, 04:32:20 PM by uniquorn »

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Re: MOSAiC news
« Reply #351 on: December 02, 2019, 04:46:56 PM »
Quote
coordinates taken from polarview images in red and collated
Coordinates  were shared earlier from the 106 Sentinel-1AB images available since the Polarstern moored on Oct 4th. These were hand-digitized using the fast and accurate new PolarView plugin.

No new S1AB images have appeared during the last 48 hours, very unusual. It means during all 16 orbital passes over the Polarstern, the sensors were either shut down, malfunctioning, taking scenes in interferometric mode, or taking images but suspending distribution. This happens every time the Mosaic floe is encountering disintegration issues. Coincidence?

The P-buoys give the ship's position 2-3 times a day, always in the early morning UTC hours. The accuracy is about a third of the ship's length. The timestamps refer to nadir or satellite passage over the center of the scene. While these are more accurate than we need (to the second), the minutes can be anywhere between hours.

Like most buoys, the three close-in P-buoys call in their GPS coordinates 24 times a day, every half hour on the half hour. Since 4 dp accuracy is important to measure ice pack deformation, the issue arises of how to best collate them with the erratic timestamps of Polarstern S1AB images.

The Polarstern's lat lon is seldom co-temporal with the buoys, only 15 times out of 106. However the other 91 can be linearly interpolated back to the nearest half hour using the rate of change of lat lon. The ones below are already synched to the buoys and do not need interpolation:

S1B   2019 11 29 T 0400   86.1220   115.0394
S1B   2019 11 22 T 0230   85.7352   120.8192
S1B   2019 11 19 T 0700   85.8011   120.5766
S1A   2019 11 18 T 0530   85.8556   120.8340
S1B   2019 11 17 T 0400   86.0595   122.4405
S1B   2019 11 10 T 0230   85.8219   115.9915
S1B   2019 11 07 T 0700   85.9198   116.7922
S1A   2019 11 06 T 0530   85.9191   117.7247
S1B   2019 11 05 T 0400   85.9509   118.8770
S1B   2019 10 26 T 0700   85.4533   127.4991
S1B   2019 10 19 T 0530   84.9215   133.1910
S1B   2019 10 14 T 0700   84.7783   134.5386
S1A   2019 10 13 T 0530   84.8574   135.0090
S1B   2019 10 07 T 0530   85.0846   134.3174

The Pbuoy dataset has various repairable glitches (shown below) not repaired by the buoy owner; the month-old errors are simply passed on 'as is' to the Meereis and sailwx portals to be ingested into Uniq's animation algorithm.

Since 94 - 12 - 3 = 79 other Mosaic buoys are currently reporting -- and some of these will have glitches of their own -- there is a need to repair the damage and regularize the data.

The best way to go is set up a master clock, say on the half hour back to the beginning, then hang all the data off it to synchronize analysis. Although Mosaic experiments often produce complex data types that don't fit in (below), they still be indexed in if that serves some purpose.

For example, a source like GFS nullschool only reports at 3 hr intervals so has gaps at 5 out of 6 positions, whereas sailwx and awiMet shipboard weather report hourly. Ascat reports 3 times a day but swath timestamps are hard to come by for the concurrent PS location. OsiSaf reports a rolling window of ice movement every two days between 12:00Z. Most satellite products (such as Amsr2 ice concentration or cryo2smos ice thickness) report every 24 hours.

On these forums, we are looking for scalability, transparency, regularization and portability:

Scalability: Any number of buoys or images can be tied to the master clock's indexing field; indeed all put into a single common file. The issue is keeping file size manageable over the course of the Mosaic year. If not, the latency on common operations like 'sort' or 'fill down' becomes unworkable. The key here is keep image collections such GFS weather pictures elsewhere, still indexed though by the master clock.

Transparency: This means suppling the data in human-readable data or image format such as plain txt, comma separated variables, netCDF, kml, gif, png, jpg or mp4 visible in the post itself or as an attachment anyone with an old cheap computer can download, open in free software and process for themselves. More and more climate change sources are using arcane binary formats the average person cannot work with.

Regularization: Errors, gaps and glitches should be repaired just once, rather than 50 people making the same tedious repairs 50 times over. To a certain extent, this is enforced by keying to the master clock. I will post repaired P-buoys, synched S1AB and reconciled sailwx/awiMet in a bit.

Correction and collation of databases can be done very rapidly if you still have a 25 year old Mac running MS Works 1.0; it has gotten much harder since.

Portability: The data should be immediately importable into other open software for specialized projects, such as Excel, Gimp, ImageJ or R for statistical analysis, charting, slide shows, animations and movies.
« Last Edit: December 02, 2019, 06:18:01 PM by A-Team »

A-Team

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Re: MOSAiC news
« Reply #352 on: December 02, 2019, 05:15:02 PM »
Co-leader M Shupe has an excellent new on-site blog out; note that despite the Nov 27th tag the storm event being discussed only covers the 18-23 Nov 2019. More has happened since then

We could see the damage just looking at S1AB time series but it is great to have confirmation and  specific details beyond satellite resolutioon. Note buoys are not on the Mosaic floe and may be affected differently or not at all.

I don't think things would have gone better had they selected another floe; the ice was garbage everywhere at their latitude on Oct 5th and still is. Had they gone closer to the pole, transpolar drift would have become even more problematic than it is now: the GFS wind forecast translates heuristically to more south and east backtracking of their trajectory.

85.9  113.8 19-12-02 09:00    8  250    -27.1
85.9  113.4 19-12-01 21:00    8  300    -24.1
86.0  113.1 19-12-01 09:00   10  310    -21.8
86.0  112.8 19-11-30 21:00    8  340    -27.0
86.1  112.9 19-11-30 09:00    9   20    -28.0
86.1  113.5 19-11-29 21:00   10   30    -25.8

Quote
Postcards from a frozen icebreaker – Part 14
By Matthew Shupe 11/18/19
https://blogs.agu.org/thefield/2019/11/27/postcards-from-a-frozen-icebreaker-part-14/

I was startled by the phone call shortly after midnight. Trouble at Met City. Felix had just arrived on the bridge for his night watch from 12-4am. He always takes a look around camp when arriving for his duties. And there was no 30m mast. Simply gone.

We had seen the crack before, and apparently it got active and pulled on some of the guy lines, ultimately pulling the mast down. The sonic anemometer failed right away, possibly from just being unplugged. Upon later inspection it is bent, can likely be straightened, re-calibrated, and put back into operation.

Our met sensor remained operational the whole time, including [while lying on the ground] after the fall. We will test both of these instruments against others, but it is looking like they will both live to see another field measurement.

The mast itself might also be salvageable. Some bent legs the ship can likely fix and a few damaged sections that will just be taken out of service. Thus, it may become a 25m mast but that would be better than nothing. Now we just need the ice to settle down so we can think about a redeployment.

The chaos has contributed to this feeling. Major ice dynamics running from the northwest to the southeast of us, across the bow of the ship. They have sheared our camp, and the Fortress, in half. This was part of a regional event with lots of ice motion, likely driven by a strong storm with very high winds.

Initially the lead opened many meters across, followed by some shear with the far side of camp moving towards the ship, then away again. In the last days it all moved again perhaps 500m.

Met City is almost directly in front of Polarstern while Ocean City remains approximately where it was (after a slight move to stay away from the ridge). A much longer daily voyage for us to get to Met City, and now it means bringing fuel cans to run generators. Met City is now very dark.

“Continuity” is a very important concept for MOSAiC. But it’s also a huge challenge in the current Arctic conditions. In the last week we’ve had so much ice movement, right out in front of the ship. We watched Met City move back and forth across the view from the bridge.

Intermittently we are able to reach it, going from floe to floe. While at other times there is no access possible. And this limited access impacts the continuity of our measurement on the ice. We are running Met City on a couple of generators but the runtime is such that we must refuel twice per day.

Last night the ice movement left us no route to Met City so the generator fan went out at 4:30 am local time. This limited access is leaving its mark on the Met City data stream but others experiments are also impacted.

Sampling sites have move further away or broken up entirely; the Ocean City hut had to be moved; the whole Remote Sensing installation will need to be relocated, and more. Continuity of the observations has definitely been compromised.
An outdated map of the Ice Camp layout was included, not attached below because it is one we have seen before, now presented at a blurrier resolution. It does not show the layout of the cracks and ridges discussed in the post.

Once again there is nothing but 404's in trying to locate the original full resolution file. Neither the new lidar elevation map nor ice bottom ROV imagery have been released in any form.

Last time I wrote the help desk, they got back to me saying the ship could only be contacted intermittently, even though we know today it had a 100 mbps internet connection ever since leaving Tromsø.
« Last Edit: December 02, 2019, 06:09:05 PM by A-Team »

gerontocrat

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Re: MOSAiC news
« Reply #353 on: December 02, 2019, 07:06:21 PM »
The MOSAIC expedition was designed, funded and implemented on a simple single basic assumption, namely that there would be a nice big thick solid floe that would remain intact throughout the entire freezing season as it drifted around the Arctic.

Re-reading the early posts, it is difficult not to conclude that the floe chosen was the best of a very bad lot as there was no time left to look further.

Barneo 2019 was abandoned.

Mike Horn and Borge Ousland have had and are having an awful time on their little North Pole skiing expedition
Quote
Horn lamented the changing sea ice: “[It] is not only shrinking in size, but it has also become younger and thinner in recent years. This causes the ice to break up and move a lot faster than it used to, which are two of the biggest challenges we have encountered so far.”

So perhaps the MOSAIC expedition's basic assumption no longer holds? i.e n years too late?

Perhaps the methodology, i.e. continuous measurements on and of a single floe, no longer reflects the polar winter ice reality?

Perhaps the new reality is continuous change as ice moves, breaks up, reforms into different patterns?
_____________________________________________________________
Mike Horn's expedition...
https://forum.arctic-sea-ice.net/index.php/topic,2886.msg239192.html#msg239192
https://explorersweb.com/2019/11/26/ousland-and-horn-to-be-evacuated/
https://explorersweb.com/2019/11/29/ousland-and-horn-dig-deep-150km-to-finish/
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

uniquorn

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Re: MOSAiC news
« Reply #354 on: December 02, 2019, 09:21:27 PM »
drift update, 3 close Pbuoys and PS estimated location, ~10days in 50frames

uniquorn

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Re: MOSAiC news
« Reply #355 on: December 02, 2019, 09:51:39 PM »
Perhaps the new reality is continuous change as ice moves, breaks up, reforms into different patterns?
Indeed. Late refreeze and rapid extent gain maybe has it's own problems. More obvious stretch marks perhaps.  https://go.nasa.gov/35U33jv  nov27-dec2, ctr

A-Team

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Re: MOSAiC news
« Reply #356 on: December 02, 2019, 11:33:23 PM »
Quote
Mike Horn and Borge Ousland have had and are having an awful time... Perhaps the whole concept of continuous measurements on  a single floe, no longer reflects the polar winter ice reality?
The two adventurers are looking at very unfavorable ice movement for the next four days that will take them north and west faster than they can walk. The same thing happened to Nansen's foot party. The image below plots their nrt position at 08:29 utc 02 Dec 19 over nullschool GFS.

The idea of rescuers reaching them by sailboat or bringing food on skis seems very naive looking at the massively fractured ice leads (https://go.nasa.gov/2raOaKW). The two are within helicopter range and discussing airborne rescue before the winds worsen as predicted; visibility and pilot safety are additional issues. 

The Polarstern lost a helicopter pilot in Antarctica a few years back with multiple scientists injured.

It's not clear what to measure to show/not show the ice is shearing, compacting and diverging more than it did, to what extents this year is natural and unnatural variation off a weak 2018-19 winter, and whether the mechanical properties of the ice have deteriorated.

We've previously looked at the August, September and early October history of this floe. Basically it was newly formed from collisions and a barely consolidated mess as late as the Oct 2nd S1AB. Still, what were they going to do after eight years of planning and grant-writing. Wait for the ice to freeze solid, then set up in the dark?

http://bslmagb.nerc-bas.ac.uk/iwsviewer/?image=DataPolarview/111_S1jpeg2000_201910/S1B_EW_GRDM_1SDH_20191002T070002_5B93_N_1.8bit.jp2

Up thread, I laid out Plan B options. The best idea is probably to pull in all the remote equipment, set out more buoys from the relief icebreaker arriving, draw up the ice anchors, squirrel the shp around make an open patch of water, point the bow (where the key instruments are) into the wind to avoid the massive air pollution affecting them now, and change locations under powered drift.
« Last Edit: December 04, 2019, 09:15:02 PM by A-Team »

gerontocrat

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Re: MOSAiC news
« Reply #357 on: December 03, 2019, 01:33:24 PM »
I guess the MOSAIC expedition is having another rotten day.
"Para a Causa do Povo a Luta Continua!"
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uniquorn

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Re: MOSAiC news
« Reply #358 on: December 03, 2019, 02:25:41 PM »
Quote
It's not clear what to measure if the ice is shearing, compacting and diverging more than it did
Had a look at osisaf for today but it only goes back to 2015 and wouldn't be representative (ctr). Is there a monthly drift somewhere that might give an overview of possible increase in mobility over the years. (or average the arrows over a month somehow?)

A month of meandering mosaic drift, nov2-dec3. Another acceleration yesterday. ~31days in 150 frames.

Woods Hole Oceanographic Institution, owners of itp102, part of the mosaic buoy network, give a nice overview of drift on their site and at the moment mosaic align quite well with annual drift. https://www.whoi.edu/page.do?pid=165676
« Last Edit: December 03, 2019, 03:18:36 PM by uniquorn »

Tor Bejnar

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Re: MOSAiC news
« Reply #359 on: December 03, 2019, 03:20:54 PM »
The 'dance' is beautiful to watch.

 Is there some way to indicate how much (if any) the distance between buoys changes over time?
Arctic ice is healthy for children and other living things.

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Re: MOSAiC news
« Reply #360 on: December 03, 2019, 03:34:04 PM »
Quote
Is there some way to indicate how much (if any) the distance between buoys changes over time?
Yes. Put the three buoy lat lon columns in a spreadsheet, making sure their half-hour time stamps are in register. Add the haversine formula (http://mathworld.wolfram.com/Haversine.html) as 7th-9th columns to calculate sides. Add a 10th column that sums these to a triangle perimeter. Use the SSS formula sqRT (s(s-a)(s-b)(s-c) with s the semi-perimeter for the area. Draw each triangle using an online triangle tool, capture, bin-color in proportion to area, float as otherwise transparent layers and animate. YES YOU CAN

date   hour   lat-P201   lon-P201   lat-P204   lon-P204   lat-P207   lon-P207
01 12 19   03:00   85.9394   113.4152   85.9400   112.7791   86.0074   112.4806
01 12 19   02:30   85.9413   113.3999   85.9420   112.7633   86.0093   112.4640
01 12 19   02:00   85.9432   113.3855   85.9438   112.7479   86.0111   112.4486
01 12 19   01:30   85.9450   113.3719   85.9457   112.7335   86.0128   112.4341
01 12 19   01:00   85.9467   113.3608   85.9474   112.7194   86.0146   112.4214
01 12 19   24:30   85.9485   113.3505   85.9491   112.7078   86.0163   112.4103
01 12 19   24:00   85.9503   113.3405   85.9509   112.6973   86.0180   112.3994

The tool below will put your choice of inter-buoy distance along the bottom rescaled to a constant length. Then you can see the relative shape change in the other two sides.

https://www.triangle-calculator.com/?q=a%3D3+b%3D4+c%3D5&submit=Solve

Quote
average the ice motion arrows over a month somehow
In the past we have tried loading the month as grayscale in gimp and using the 'average layers' command on a duplicated stack (image menu). That gives a so-so wind rose at each grid point that could be compared year on year by image subtraction to give a 2015-19 animation.

It may be that OsiSaf ill-advisedly puts the center of the arrow over the grid point (as mosaic_multi does) instead of the tail. So we need to first redraw the arrows with no heads using the OsiSaf netCDF than no one can get to work. Alternatively Panoply (or command line) dumpNC would give numeric x,y values at grid points or regions of interest that could be passed on to Excel which has a good wind rose chart.

The next three days or so on GFS look like more of the same: moderately strong winds at a fixed bearing. Below, the png assumes a mid-range coriolis angle of 25º of ice movement CW to the direction of the wind. Zonal and meridional components r,θ = lat lon are shown for the 05:00Z nullschool of today roughly scaled to the cube of 100 hPa wind speed from comparing response at periods of constancy.

In three days time, my expectation is the Polarstern will drift to 86.2  121.9 (ie on 09:00 on 06 Dec 2019 according to sailwx tables). Thus 1/6th of the trip will be over without any real indication of Fram-ward transpolar drift.

Sentinel coverage of the Mosaic floe has resumed. Daily instability suggests very little of it is fit for purpose.

S1B  2019 12 03 T 0643  17  210  -17.1  86.0017  115.6685   

http://bslmagb.nerc-bas.ac.uk/iwsviewer/?image=DataPolarview/111_S1jpeg2000_201912/S1B_EW_GRDM_1SDH_20191203T064336_4414_N_1.8bit.jp2


Technical note: nullschool provides a clean 1º graticule over land if wind is set to none. AwiMet provides the green location circle. Setting the scale parameter to 3000 maximizes resolution. Longitude has been increasing by 0.05 deg/day over the last 24 hours but latitude by only 0.005, setting the wind scaling. (Mean recent change or tangent to the PS position curve could be determined more accurately with high resolution S1Ab or buoy data.)

The tangent vector is set by rotating to vertical using the Polarstern's current longitude, drawing a perfect horizontal, then rotating back. The wind direction is drawn as the tangent vector to the radial vector of the osculating circle to the curving wind sprite at the PS. Dropping the perpendiculars then gives the desired breakdown of motion in terms of lat,lon. Here taking the ratio of r,θ component vectors causes the wind scaling factor to drop out.
« Last Edit: December 04, 2019, 12:08:24 AM by A-Team »

uniquorn

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Re: MOSAiC news
« Reply #361 on: December 04, 2019, 03:27:36 PM »
drift update, 3 close Pbuoys, ~7days in 50frames. Retracing at speed.
small steps, Tor, small steps :)
edit: updated below
« Last Edit: December 05, 2019, 10:44:27 PM by uniquorn »

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Re: MOSAiC news
« Reply #362 on: December 04, 2019, 04:33:17 PM »
Quote
take the time to get it right Tor.
Given the very small patch occupied by the three buoys, it would be ok to forget the WGS84 ellipsoid and for that matter the spherical earth and just work on its tangent plane at a buoy triangle centroid. So, using the buoy positions as lat, lon = r,θ of plane polar coordinates = rcosθ, rsinθ (lat in S1AB pixels, lon in radians) = x,y cartesian, it is a matter for high school trigonometry.

What about using mean wind speeds from reanalysis as a proxy for ice motion to make a month on month comparison to Nov 2019? That data is readily available quite a ways back. We could wonder how accurate it is for the Arctic Ocean given the near-total lack of instrumentation but that might not much affect anomaly or trend estimations.

However wx'ers steer clear of near-surface wind wind prediction whereas that is precisely where wind stress on the ice arises. And for that, ridges and floe edges (aka freeboard, thickness) provide the primary frictional surfaces. How much do we know about these even in the Polarstern year? Next to nothing. Assuming they're the same defeats the whole purpose of the wind proxy: more wind but less surface friction would look very similar to less wind and more friction.

Three Sentinel-1B came in this morning. The Polarstern ducks being all in a row already, there wasn't much to do (1st image) except translate them sideways to tomorrow's prediction based on strong steady winds forecast at GFS-null.

The animation of the 3x close-ups do not indicate any rifting or ridging though the turmoil continues on the Mosaic ice camp area (which was a jumble of unconsolidated blocks to begin with). The faint white diagonal indicates the direction of travel to left.

However the ship is entering an area in the anti-cyclone lee of SZ, suggesting ridging if winds converge, or shear if wind speeds differ (4th image). Winds faster than 14 m/s are considered gale force (table below). Use keyboard 'k' to advance 3 hrs, 'shift-k' to advance 24 hrs on GFS:

https://earth.nullschool.net/#2019/12/05/0900Z/wind/isobaric/1000hPa/orthographic=-45.00,90.00,3000/loc=118.600,86.100

We have no accurate way of placing the Polarstern (green circle) latitude forward on GFS predictions, a significant issue given sustained wind speeds. Sailwx sishowing the ship a whole degree of longitude east in the 9 hours since the last S1AB):

  86.1  119.1 19-12-04 15:00   16  230    -16.7
  86.1  118.1 19-12-04 06:00   12  240    -14.7

D 2019 12 04 T 0546   86.0937   118.1062 which is 434.4 km from Pole
C 2019 12 04 T 0408   86.0891   117.9333 which is 434.9 km from Pole
B 2019 12 04 T 0230   86.0839   117.7657 which is 435.5 km from Pole
A 2019 12 03 T 0643   86.0017   115.6685 which is 444.6 km from Pole

DC Distance:   1.411 km in 1.633 hrs for 0.864 km/hr or 20.7 km/day
Initial bearing:   248° 20′ 42″
Final bearing:   248° 10′ 21″

CB Distance:     1.397 km in 1.633 hrs for 0.855  km/hr or 20.5 km/day
Initial bearing:   245° 38′ 14″
Final bearing:   245° 28′ 12″

BA Distance:   18.51 km in 19.78 hrs for 0.934  km/hr or 22.4 km/day
Initial bearing:   239° 54′ 19″
Final bearing:   237° 48′ 47″

DA Distance:   21.3 km in 22.55 hrs for 0.945 km/hr or 22.7 km/day
Initial bearing:   242° 31′ 00″
Final bearing:   240° 05′ 05″
« Last Edit: December 05, 2019, 02:49:16 AM by A-Team »

A-Team

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Re: MOSAiC news
« Reply #363 on: December 05, 2019, 01:58:38 PM »
The Polarstern continues to drift very rapidly east (ie the wrong way) and slowly north. The winds have been in the double digits for the last 61 hours, averaging a 14 m/s gale force push at~50 km/hr. The direction of the wind has been remarkably steady at 240º.

GFS-null shows this drift will continue for 2-3 days as the anti-cyclone center elongates to the north as it dissipates. Wind vector constancy presents an opportunity to determine the 'Nansen angle' of ice drift relative to wind under these conditions and to predict Polarstern drift a few days out.

The issues here are the ground accuracy of GFS and the optimum scale for angle measurements as nullschool. The url can be fed the nrt position data from sailwx, currently 86.1  121.1  11:00   14  240. At maximum resolution, a rapidly moving Polarstern moves noticeably on GFS nullscape.

Here position-specific daily (or 3-hour) urls at the time of S1AB, say 05:00z can be manufactured by a simple merger of AWImet and any initial GFS url. It would be great to have this back to the mooring date of Oct 4th at a couple of scales as an mp4. Note gimp side panel thumbnails show high velocity winds at a glance. Production at 3 hr intervals would require an automated procedure as 8 per day * 60 days * 2 scales = 960 is out of reach of manual methods.

https://earth.nullschool.net/
#2019/12/05/0500Z/
wind/isobaric/1000hPa/orthographic
=-45,90,3000/    Greenland down, north pole centered, scale
loc=121.1,86.100 longitude and latitude of Polarstern

The two new Dec 5th Sentinels show continuing turmoil within the Mosaic experimental area. A relief icebreaker is on its way, sort of. There is currently a 949 hPa cyclone in the north Atlantic between this ship and the Arctic Ocean.

Quite a few scientists from leg 1 will be returning to shore. Leg 2 is seen as the most difficult because of unrelenting cold, darkness and wind. It appears a new communications officer is coming on board; that might help us stay better informed.
« Last Edit: December 05, 2019, 04:03:00 PM by A-Team »

gerontocrat

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Re: MOSAiC news
« Reply #364 on: December 05, 2019, 06:41:22 PM »
It seems the Russian icebreaker, "Kapitan Dranitsyn" has now left port  (Tromso) and is on its way.

It also seems it will divert, if necessary, to help getting Horn and Ousland off the ice, and maybe rescue  the Norwegian research ship «Lance» which has got stuck trying to get to the two men.

https://thebarentsobserver.com/en/arctic/2019/12/russian-icebreaker-set-out-tromso-course-ice-locked-german-research-ship
A Russian icebreaker set out from Tromsø with course for ice-locked German research ship
The «Kapitan Dranitsyn» is bringing equipment, supplies and 95 researchers to the «Polarstern» as part of great international research expedition MOSAiC.


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Re: MOSAiC news
« Reply #365 on: December 05, 2019, 08:23:00 PM »
The whole ending strikes me as highly contrived, all about filming a meet-up with two buddies and later them eating ribs and french chocolate. The Lance has a helicopter pad but they are not using it so the adventurers will be able to say they went boat to boat per the original plan.

The tent camp is also well within reach and capabilities of the Svalbard helicopter service that extracted the crew from the grounding in the Hinlopen Strait last December.

The Lance does not really have to chops for this job and keeps getting frozen in the 30 cm ice but they are scripted to moor along an ice edge so the two do not have to be seen being picked up from a zodiac even though they are having to be rescued as they don't have the food or fuel to continue under current ice conditions and more weeks of unfavorable floe drift.

There is a Norwegian icebreaker at the scene but they are not using it. The Polerstern's relief icebreaker is not likely to be headed towards Svalbard -- way out their way and through more ice than necessary. These ships have all turned off their GPS beacons; sailwx is only receiving the Polerstern's.

Updates -- and some pointed questions about an actual purpose for the trip -- can be found in the comment section at this Norwegian site which updates almost hourly:

https://direkte.vg.no/nordpolen_ousland/news/5de62459d45a8b0011b1677f

Quote
Just before Lance left Longyearbyen, a research ship also left north. I see on Marine traffic that this ship is on standby on the ice (on starboard side of Lance), probably be the new state-of-the-art icebreaker for the Norwegian Polar Institute, "Crown Prince Haakon" a research assignment in the area and can contribute if necessary. The name may be icebreaker Haakon Magnus "is located just to the east of you, can't they break a real trap for you?

How much does it mean for the expedition to go "unsupported", which is not possible with post-supplies? And how do they manage to meet in the icy, dark and snowstorm. Even with GPS and satellite phones, this must be a major challenge. The two teams of polar explorers have agreed on a common point on GPS that they both are heading towards.

Bengt Rotmo and Aleksander Gamme, friends coming on foot to the tent camp, have emergency rockets and a signal gun too, so they can use it to show where they are. There is a doctor on board the Lance though no issues are expected.
« Last Edit: December 05, 2019, 08:42:30 PM by A-Team »

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Re: MOSAiC news
« Reply #366 on: December 05, 2019, 10:49:40 PM »
drift update, 3 buoys close to PS, ~8days in 70frames.

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Re: MOSAiC news
« Reply #367 on: December 06, 2019, 12:38:31 PM »
Some large scale north-south extensional fissures have opened up, a long 600m wide crack to the east of the Polarstern and a (so far) smaller one right through the Mosaic floe a few tens of meters west of the ship.

Even a small displacement in Ice Camp disrupts power lines, towers, generators, experimental equipment and repair access. Here the lead is approximately 100m wide (2-3 pixels on S1AB 40m).

This followed 72 straight hours of wind speeds in excess of 10 m/s at the ship's location, attributable to its position in the north-central winds of a persistent anti-cyclone centered in the New Siberian Islands.

On the next post, the relevant GFS nullschool sequence shows that sharp curvature in the applied wind stress from the tightly coiled anti-cyclone was incompatible with increasingly brittle ice, which then shattered along north-south lines to accommodate to applied forces.

The 05:30 scene will apparently be the only S1AB today as the 07:00 orbital pass was either not taken or suppressed. It is hard to believe that both A and B satellites would have higher scheduling priorities at such an obscure location during a dramatic moment in an historic Arctic expedition. Surely AWI has closer connections to schedulers at ESA Copernicus than foreign researchers; eight years of planning went into Mosaic.

In any event, we don't know if the 05:30 caught the beginning, end or middle of the lead opening. It could be growing to the size of the one to the east; alternatively it may have peaked earlier and now be closing. Previous images show that this is not a new fault but rather reactivation of an older lead.

Note a second fissure comes in from the west (3rd image). This too has opened and closed repeatedly over the last two months.

The final image shows a rare cloud-free swath of heat map of the area around the Polarstern a few days back. The white lines are leads that, despite being frozen over, still leak more heat to the atmosphere than surrounding thicker ice and so are brighter when imaged in the infrared.

Neither lead can be attributed to the PS and AF icebreakers maneuvering about during the initial mooring to the Mosaic floe, though we might wonder how the relief icebreaker Kapitan Dranitsyn will get in close enough to refuel the Polarstern.

Insulting official expedition communications from 'Follow Mosaic' feature inane pictures of omelets and baked goods from the Polarstern kitchen, along the lines of arranging deck chairs on the Titanic. Shupe's AGU blog, the only real source of information, has not been updated since November 18th. It has a nine day lag between its writing and its posting.

A new Helmholtz post on PS site mitigation appeared on Dec 4th but seems dated, non-specific and smiley-faced about disruptive floe events, insuperable problems obtaining data continuity over a year and tainting of air quality data by the ship itself. (On past expeditions, the PS stayed pointed into the wind, allowing fresh air to reach bow instruments).  One interesting point however about wastewater:

Quote
When it comes to the outlet for our filtered wastewater (technically clean water), a pump system was installed on Polarstern that reintroduces the salt previously removed from it, before discharging the water at a depth of ca. 150 m. The times at which these ‘dumps’ are made are documented, allowing any potential influences on them to be identified after the fact.

By far the best reportage is coming from Martha Henriques at BBC. The Dec 3rd post links back to the others. Byron Bloomquist of CIRES NOAA is also posting detailed damate reports.
https://mosaic.colorado.edu/blogs. AWI, the expedition lead, gives out no information whatsoever.

https://www.bbc.com/future/article/20191129-what-will-an-ice-free-arctic-look-like?
https://mosaic.colorado.edu/blogs

Quote
Markus Rex of AWI, expedition leader, shows me the trajectory of the drift so far on a screen in the Red Saloon, one of the ship’s common rooms. There is a pattern in the meandering line on the screen that shows one reason that cracks and pressure ridges have been appearing in the camp.

“You see these cycles here?” he traces a line in the shape of a scalloped edge. “It’s fast here, then it’s always slow, slow, slow.” He stops at a pinch point on the line. “These are the points when we get the high pressure.” That’s when the floe is twisted and pulled in different directions.

At least there is some predictability in these cycles but still, but as Rex watches the screen inside the Red Saloon, it’s clear that there is little the team can do but hope the damage to instruments and infrastructure each time won’t be too great.
« Last Edit: December 06, 2019, 05:53:18 PM by A-Team »

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Re: MOSAiC news
« Reply #368 on: December 06, 2019, 01:48:34 PM »
To me it looks like the MOSAIC project has had some windy times but not a real humdinger. So I did a google to see if they should expect one.

Perhaps they should, especially in this month.

https://www.nature.com/articles/s41598-019-45574-5
Winter storms accelerate the demise of sea ice in the Atlantic sector of the Arctic Ocean
Introduction

Quote
The strongest storms in the Arctic Ocean typically occur during winter and originate from the North Atlantic Ocean1,2 (Fig. 1). The number and intensity of Arctic winter storms has increased over the period 1979–2016. These storms often generate strong southerly winds that transport heat and moisture into the Arctic from the mid-latitudes, contributing to record breaking winter temperatures.

https://iopscience.iop.org/article/10.1088/1748-9326/aa7def
Extreme cyclone events in the Arctic: Wintertime variability and trends
Abstract

Quote
Typically 20–40 extreme cyclone events (sometimes called 'weather bombs') occur in the Arctic North Atlantic per winter season, with an increasing trend of 6 events/decade over 1979–2015, according to 6 hourly station data from Ny-Ålesund. This increased frequency of extreme cyclones is consistent with observed significant winter warming, indicating that the meridional heat and moisture transport they bring is a factor in rising temperatures in the region. The winter trend in extreme cyclones is dominated by a positive monthly trend of about 3–4 events/decade in November–December, due mainly to an increasing persistence of extreme cyclone events. A negative trend in January opposes this, while there is no significant trend in February.
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Re: MOSAiC news
« Reply #369 on: December 06, 2019, 05:08:52 PM »
Below, a summary of weekly blog posts from Byron Blomquist, CIRES and NOAA. The event this morning appears catastrophic even relative to earlier havoc at the Mosaic floe. An update can be expected Monday. Dec 9th.

The scientists' persistence to stay operational under difficult weather and ice conditions is only to be applauded but as with a poker hand, there is a time to hold 'em and a time to fold 'em.

The event this morning may prove a tipping point. The original plan, conceived eight years ago, is no longer viable in the ice of today. It is time for Plan B.

GFS foresees a lull for the next five day: slow drift north but in the direction of Ellesmere Island, not the Fram Strait.

https://mosaic.colorado.edu/news/weekly-update-byron-7

“December 2. The Dranitzyn left the coast of Norway yesterday to begin the transit to our location and should arrive within a week to 10 days. AWI estimates it will then take about 5 days to transfer ~50 tons of cargo between the two vessels and pump over the fuel, weather conditions permitting. We were not able to accomplish everything we planned for leg 1 having to overcome a series of setbacks related to ice dynamics.

The route to Met City was reestablished over the past week and the main power lines reconnected, so most of the instrumentation there is back on line. The ship's machinists repaired damage to the collapsed 30m met mast and we hope to reinstall it as a 23m mast sometime next week.

Air sampling from the bow is often good for several days running, then unsuitable for several days as the wind direction shifts to the stern of the ship.

The anemometers, CO2/CH4 flux system, fast ozone, slow ozone, NOx, GCMS, and mercury instruments have all been running well. The DMS mass spectrometer ran for a few weeks, but a power supply failure will keep this system off line until leg 4.
 
Nov 25, 2019. The passage of two arctic cyclones last weekend was a unique opportunity to make atmospheric observations of a poorly understood weather system. There were no major shifts in the ice pack over the last several days but the situation remains dynamic, with leads opening and closing on a daily basis.

The remote sensing site has been dismantled and will be rebuilt at a new site. The ROV site is partially operating on generator power. The Ocean City site was dismantled and moved to avoid an ice ridge, but is mostly operational again.

The situation at Met City is tenuous. Met City is still without a power line but instruments on the tower are operating part of each day on generator power and we've been able to access the site twice daily to refuel. It is sometimes possible to reach Met City by snow machine, but often access is by foot only.

The exact route changes daily, depending on ice conditions. Met City is currently only about 400m from the ship, but the route over ice is probably closer to 1 km. Our measurements there are still shutdown and we don't have a good estimate yet for when the power and data lines will be reestablished.

After the large shift in the ice floe on 19 Nov, the Met City, ROV and remote sensing sites moved about 600m to the SE, across the bow of the ship. Met City is now located directly in front of the bow and the remote sensing site will be reestablished in this same general area. Ice in front of the ship is now a complex system of blocks and ridges. The ROV site is now off the port quarter of the bow.

The formerly compact Central Observatory site now spreads over a much greater area and the bow of the ship is largely surrounded by on-ice infrastructure. If the ice solidifies in this state, this will be the arrangement for the remainder of the project. This will impact the clean wind sector for measurements from the bow of the ship, but there should still be many hours per day with minimal activity on the ice.

November 15-17. A powerful winter storm blew through the scientific cities set up on the ice around the ship. Intense winds tore new cracks in the ice floe next to the ship, sending some ice-based instruments adrift. It’s possible that the floe will drift back together and freeze again. I think about the word “mosaic” and how it implies a breaking in order to be put back together.

Eventually the drift slowed down. The instruments moved in a U-shape around the bow of the ship. ROV Oasis is now off to the left. Remote Sensing not far by. Met City is directly in front of the bow. Ocean City and Balloon Town stayed in relatively the same position, but a long lead opened directly next to their tents.

The Atmosphere Team’s flux stations, part of the distributed network, are doing great, overall, although we had one disruption that involved a polar bear. We have snapped cables and a dismembered exhaust system to repair. We are working to rig new connectors and cables, and have ordered a new exhaust pipe that will hopefully arrive with the next leg of participants in December.

Due to a major storm in the last few days, we have also had lots of cracks around the ice, and one has opened up so wide that in order to get to our instruments, one has to use a kayak to cross to the other side.

The 30 meter tower has tipped over. An assessment of the instruments and damage done to the tower are still on-going. Our other 11 meter tower is still standing tall, but another smaller crack has opened beneath one of the guy-wires that holds up the tower.

Nov 19, 2019. The last several days have seen some dramatic developments and some setbacks.  On Saturday a strong arctic cyclone moved through the area, bringing sustained winds up to 20 m/s for many hours, first in an westerly direction, then veering to northerly. Our drift rate increased to > 0.5 kts to the E and then to the S, at one point up to 0.8 kts. We are now well S of our position a week ago and are once again on a track toward Siberia.

The large multiyear floe which was selected as the backbone of our Central Observatory split in two on Sunday, with a significant shear zone developing just in front of the ship in a port-starboard direction.

This lead has opened and closed a few times over the past 48 hours and the shear between the two halves is currently offset by as much as 70-100 m. The block with Met City, ROV City and the Remote Sensing Site are on the opposite side of the crack and a large ice ridge is developing between Remote Sensing and Ocean City.

The Remote Sensing site was heavily damaged by ice movement and a number of large instruments were moved to safety on Sunday. The site will need to be reestablished at another location when the situation stabilizes.

The power and data links to Met City and all other sites on the opposite side of the lead were severed early AM on Sunday. Further ice movement brought down the 30m met tower at Met City early this morning. Otherwise, most of the equipment installed at Met City is intact and appears to be on stable ice, but only a few instruments are operating, powered by intermittent backup generator supply.

Our CO2/CH4 flux system at Met City is down and will not operate until ship power is restored to the site. Met City was originally located about 800m off the starboard beam of the ship at a 2 o'clock bearing, but as of today is drifting toward the 1 o'clock position. Because the ice is still moving we do not know when power and normal operations will be restored.”
« Last Edit: December 06, 2019, 05:51:35 PM by A-Team »

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Re: MOSAiC news
« Reply #370 on: December 06, 2019, 05:43:00 PM »
^^ There might be the answer why we don't get more data... :(
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Re: MOSAiC news
« Reply #371 on: December 06, 2019, 07:34:57 PM »
Quote
why we don't get open data from Polerstern / Mosaic?
I looked into a Freedom of Information request for the ship's log, gps location and heading at ten minute intervals and so on. I have done these requests before in the US, followed by successful but time-wasting lawsuits when inevitably they don't comply.

This probably wouldn't go anywhere with NSF grantees like Shupe and Blomquist who are already posting quite a bit of timely disclosure in their realms. The US kicked in $26m; grants will be monitored.
Now a FOIA could get some BS stonewalling such grantees have a right to first use of experimental data, at their leisure (ie 2023 in Mosaic planning documents).

However after much commotion, NIH at least requires immediate disclosure in genomic DNA sequencing. There, a robotic sequencer ftp's its reads directly in real time to a public web archive, just like the 92 Mosaic buoys do today including those of AWI.

Here Mosaic is doing shotgun environmental sequencing and any US grantees would fall under compliance obligations. The original rationale was human health research should not be delayed; the same could be said of planetary health.

Germany/AWI of course does not fall under US domestic law but they may have something similar on the books. AWI presumably owns the navigational instruments on the bridge; on previous expeditions -- but not here, no explanation --  has always published a detailed weekly Polarstern report. It would probably take a filing from a German citizen or reporter to meet the requirement of standing.

What gets me is the deliberate dumbing down of the Polarstern's GPS location. That required a deliberate decision to actively intervene because in factory default mode and in actual onboard use, the instrument would be sending 5 decimal points instead of one. No one navigates through Arctic sea ice on 1 dp.

It all reminds me of the EA189 engine at the center of the Dieselgate scandal that continues even today with the successor EA288.

We are to believe that AWI and 600 polar scientists were surprised to learn upon arrival that the best floe around was only 30-50 cm thick instead of 1.2m. Oh sure.

A satellite unknown to science measured ice thinness during late summer but got it wrong? They made that one up.

A $150m experiment and they didn't have an old tramp steamer out there in late August drilling floes? Not to be believed.

Russianss ran 5 tourist trips to the north pole in late summer but didn't tell AWI partners about ice conditions or why they pulled the plug on Borneo? Highly implausible.

AWI knew perfectly well in advance about the problems ahead, just like VW knew about its NOx problem. Why else would you turn off ship beacons and dumb down its GPS upon leaving port?
« Last Edit: December 06, 2019, 08:30:01 PM by A-Team »

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Re: MOSAiC news
« Reply #372 on: December 06, 2019, 08:40:31 PM »
Drift comparison of p201, p204 and p207 setting the start of each track in the same place on oct11. An attempt to show distance change between buoys over time until something better comes along.
ctr
tech note: data missing on oct31 as mentioned upthread
« Last Edit: December 06, 2019, 08:47:43 PM by uniquorn »

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Re: MOSAiC news
« Reply #373 on: December 07, 2019, 08:25:37 AM »
Translation of the Arctic Drift Podcast #7 - Sturm
Release Date: 03 Dec 2019

STORM

<Narrator>

Arctic drift,  the audio log book.

The first big storm has afflicted the MOSAIC expedition in the Arctic. The ice camp around the icebreaker Polarstern was exposed to a hours lasting storm with wind speeds up to 9 (Beaufort scale). The head of expedition Markus Rex talks about the repercussions of the storm.

<Markus Rex>

Yes, last weekend we had our first big storm with harsh wind speeds up to 20 meters per second. Such a hefty blow. While the storm was forming we could see that a big crack developing but then the sight was too bad to see it. The next night the storm had clearly left some marks on the ice. The crack that developed the night before was now a shear zone, a fault zone with smaller floes and pieces of ice. All of a sudden, the whole other half of the camp magically drifted with high speed eastwards. It looked like a train scrolling by. First ROV city, then remote sensing site, then MET city passed the bow and then they vanished in the dark. This is, of course, a drastic event for our camp. After 600 meters offset it stopped.

<Narrator>

Because of the storm and the offset of the ice also the route of drift has changed. The Polarstern is still frozen to an ice floe and moves without its own engines.

<Markus Rex>

Since the storm, we moved north towards the pole but we will have westerlies according to the forecast. Which means that we are moving along the western part of our drift scenario. This is all still in a margin where we feel good about but we would like to come north more quickly. The overall way we made so far is in the upper expected range.

<Narrator>

Also, the infrastructure of the camp is partly damaged. Power and data cables are cut and need to be repaired. Until this is done fewer data can be gathered.

<Markus Rex>

Since the shear zone moved right through our camp and cut power lines, we installed emergency generators to power the equipment. But we are on a reduced measurement schedule. We are now in the process of developing a new town plan. We know what should be located where now and in the next days after we see some stabilisation we will deploy the new power and data infrastructure.

The future town plan will differ from what we have now. At the moment all the sites are in a linear line along the ice and a pressure ridge easily to protect with a tripwire against polar bears. We will though, out of necessity, have a radial layout in the future. This will be harder to protect against polar bears, but this is what nature has given us and we will live with it.

<Narrator>
Even though the negative aspects of this storm are plenty, there are also positive ones. Never before where measurements made from the inside of an Arctic storm so intensely.

<Markus Rex>

From a science perspective, such a storm is a thrilling event. This is why we are here. We want to find out how the weather systems in the Arctic work together. We have complete measurements of multiple parameters from before, during and after the storm. Energy flow, heat flux,  snow thickness, radiation, what it did to the ice. This is a unique dataset and we are amazed when we look at it. This will allow us to improve weather models. Yes, it's problematic that we will have a new town layout and that we have to rebuild a lot, but this data is what we are here for.

<Narrator>

Fortunately, there are parts of the camp that are undamaged and work fine.

<Markus Rex>

The storm has affected almost all of our sites but one. The core of our observatory, the Balloon town, which we call the town hall, is still in the same place and can be used as before even though the landscape has changed dramatically. We now have a big pressure ridge in the background and a crack in the ice behind it. I would say this has become a very attractive site with direct water access and mountains. And we can still launch our balloon.

The balloon can, of course, only be launched with moderate wind speeds, so during the storm, the balloon took no measurements.

<Narrator>

And again, this week a polar bear family visited.

<Markus Rex>

A mother with her two almost adult curbs came by. They tripped over the wire which caused two flare bombs to start. That startled them a little and the mother became cautious. They circumvented the camp in a wide bow and they did what they are supposed to do - move along in the dark. But while they were near one of the curbs couldn't resist exploring everything it could. It tried to overturn every flag and play with everything. The mother returned a few times to collect the imp. The other curb stayed with the mother all the time. You could see the curbs were only one year old but had their own personality already.

<Narrator>

When the work is done, the scientist have time for personal activities. May it be sports or just watching northern lights.

<Markus Rex>

Friday night we have opened the ice for personal use. Some played with the frisbee disc,  a soccer game took place, some went off with skis and made a tour. Of course, it was black outside, but a black with a few northern lights. We are too far north to see plenty of them, but sometimes we have them.
« Last Edit: December 07, 2019, 12:19:22 PM by blumenkraft »
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Re: MOSAiC news
« Reply #374 on: December 07, 2019, 09:46:00 AM »
Vielen Dank, Blumenkraft!
I think you are doing a very valuable job making this information on Mosaic accessible to the English-speaking world. If you can't manage to do it in future, let me know. I'm an English native speaker, but I'm fluent in German.

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Re: MOSAiC news
« Reply #375 on: December 07, 2019, 11:30:51 AM »
Vielen Dank, Blumenkraft!
I think you are doing a very valuable job making this information accessible

Thank you! :D

Quote
If you can't manage to do it in future, let me know.

Well, the translation took more time than i anticipated. I wasn't too sure i can keep it up like that. Perhaps a list of bullet points is easier to do and gives the reader the same Infos.

The new one (episode 8 ) is in my podcatcher now and i planned to translate it tomorrow in the bullet list form. If you want to do the next one (episode 9) that would be cool. I can help of course if you want. :)
« Last Edit: December 07, 2019, 11:37:01 AM by blumenkraft »
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Re: MOSAiC news
« Reply #376 on: December 07, 2019, 12:04:10 PM »
Don't think this was posted before. Makes sense to have a picture of the site when reading the podcast.

Link >> https://www.mosaic-expedition.org/expedition/ice-camp/
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Re: MOSAiC news
« Reply #377 on: December 07, 2019, 12:13:05 PM »
That would be the 03 Dec 19 podcast though which of several storms is hard to say. Note 'pressure rig' translates to 'pressure ridge'. The follow-up 'Nach dem Sturm' is dated Dec 6th but I am quite certain it does not address the worst storm yet of the same date.

https://www.podcast.de/podcast/708698/

We remained throttled down to 1 Sentinel per day out of the 8 daily orbits passing over the Polarstern. Today the ship was just barely included on the far eastern edge of the 02:45 image. The Mosaic floe is so distorted after the massive lead openings seen at 05:30 the previous day that it is hardly recognizable, though its identity is certain from neighboring floe context.

This event likely undid much their previous ice camp restoration as well as bringing all kinds of new disruptions. The weather will be very mild the next five days so there will be an opportunity to catch up. However, going by past years, there is no reason to believe this will be the last severe anti-cyclone of the winter, on the contrary (see gerontocrat #368 above).

The ice is slowly getting thicker according to the 4 Simb3 buoys which might help subdue ice dynamics at the Ice Camp. As the ice becomes more brittle with deeper cold, that will change the character of disruptive events to less plastic fractures.

The two images below show what has happened. As noted above, the ship was situated at a hairpin of sharp wind curvature; the stress was too high at prevailing wind speeds for rigid ice to go with the flow.

I am seeing a lot of misunderstandings about ice advection in the Arctic Ocean on the part of the atmospheric physicists. Going north will never get them to the Fram Strait on the expedition time frame because a gigantic immobile block of multi-year ice is in the way.

They need to drift west to catch the circumpolar drift ('around') which is too often confused with less frequent transpolar drift ('across'). Flow has largely been zonal in recent years, not meridional (over the pole). Last year's displacement of the FYI/MYi boundary line was somewhat exceptional, with ice on the NP-Wrangel line passing over the pole (but not getting far).

So far this year, ice in the central Arctic is just milling about, the Polerstern's aimless drift is representative of a far larger region. You can see this just animating Ascat masked by Amsr2; we have that on another forum for the last nine complete years.
« Last Edit: December 07, 2019, 01:09:13 PM by A-Team »

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Re: MOSAiC news
« Reply #378 on: December 07, 2019, 12:16:35 PM »
Thanks a lot, A-Team! Fixed it.

And yes, the timeline you point out is correct. I added it to the OP.
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Re: MOSAiC news
« Reply #379 on: December 07, 2019, 01:05:22 PM »
Quote
makes sense to have a picture of the site
That one is a mirror image, an old conceptual layout. We do have the original site plan from the 126 page planning document up-forum as well as a later as-built map in radial coordinates centered on the ship. We also have the modified site plan they just released up-forum; it is no longer radial and quite blurry at all the places it has been posted.

None of these maps are at all appropriate to the pending redeployment of the Ice Camp -- if there is one -- after yesterday's big rearrangement.

uniquorn

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Re: MOSAiC news
« Reply #380 on: December 07, 2019, 02:07:30 PM »
Rapid drift to a grinding halt for direction change. Almost a handbrake turn.

edit: added a drift comparison. Spatially quite similar though one or more buoys appear to temporarily race ahead during the more rapid drift. It's possible that could be an artifact of generating the animations separately though.
« Last Edit: December 07, 2019, 03:49:49 PM by uniquorn »

gerontocrat

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Re: MOSAiC news
« Reply #381 on: December 07, 2019, 03:14:34 PM »
The weather will be very mild the next five days so there will be an opportunity to catch up.

Not so sure about that - no storm but windy enough for discomfort given the parlous state of the floe & environs?

Nullschool says 30 kmh wind tomorrow.
Gradual reduction over the next few days to 20 kmh and gradual direction change from 135 to 180o
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psymmo7

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Re: MOSAiC news
« Reply #382 on: December 07, 2019, 04:35:10 PM »
Hi Blumencraft
Leave Episode9 to me.
Glad to be of assistance.

A-Team

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Re: MOSAiC news
« Reply #383 on: December 07, 2019, 06:15:34 PM »
Quote
Leave Episode9 to me
Thanks, helpful!
Quote
Not so sure about that - no storm but windy enough for discomfort given the parlous state of the floe & environs?
Maybe but there is no double digit velocity in sight on GFS (the hourly ship wx uses m/s). All the major events so far have been at sustained gale force winds, 14 m/s or 50 km/hr.

Since the last S1AB, the ice has presumably had a chance to consolidate because of the calmest conditions yet of the expedition.

  86.2  122.1 19-12-07 10:00  4  120  -21.2  1022.1
  86.2  122.2 19-12-07 09:00  4  110  -21.0  1023.0
  86.2  122.2 19-12-07 08:00  4  100  -20.8  1023.8
  86.2  122.2 19-12-07 06:00  3   90  -21.2  1025.0
  86.2  122.2 19-12-07 05:00  2   60  -20.2  1025.7
  86.2  122.2 19-12-07 04:00  2   50  -18.3  1026.2
  86.2  122.2 19-12-07 03:00  2   70  -21.1  1027.0
  86.2  122.2 19-12-07 02:00  1   80  -21.7  1027.5
  86.1  122.2 19-12-07 00:00  2  120  -22.3  1028.7
  86.1  122.3 19-12-06 23:00  3  100  -23.1  1029.2
  86.1  122.3 19-12-06 22:00  3  100  -23.2  1029.9
  86.1  122.3 19-12-06 21:00  2   90  -23.6  1030.4
  86.1  122.3 19-12-06 20:00  2   80  -24.2  1031.0
  86.1  122.3 19-12-06 19:00  0  360  -24.5  1031.5
  86.1  122.3 19-12-06 18:00  0  360  -24.9  1032.0
  86.1  122.3 19-12-06 17:00  1  280  -25.3  1032.1
  86.1  122.3 19-12-06 16:00  3  260  -25.5  1032.6
  86.1  122.3 19-12-06 15:00  3  250  -25.9  1032.9
  86.1  122.3 19-12-06 14:00  4  260  -26.0  1033.2
  86.1  122.3 19-12-06 10:00  6  260  -25.7  1034.4
  86.1  122.3 19-12-06 09:00  5  260  -25.4  1034.4
  86.1  122.3 19-12-06 08:00  6  260  -25.2  1034.3
  86.1  122.2 19-12-06 07:00  6  260  -25.1  1034.0

That's because wind stress on the ice is not linear but grows roughly as the cube. So upcoming 7 m/s winds forces will provide only 1/27 (4%) the stress of peak 21 m/s winds seen so far.

In order to use 3-hour nullschool wind, the future position of the ship won't be at where it is today so the wind reading will be at the old location isn't applicable unless the new location can be predicted and the green circle repositioned.

However the main thing to look for at GFS nullschool is uniformity of the wind currently coming up in parallel constant-color sprites from the south. It is really abrupt changes in direction, speed and above all, curvature, convergence and divergence of the sprite lines that forecast ice disruption.

In other words, look at time series deltas using the 3000 scale in HD (high density) at the most recent ship wx position. It is these cyclones passing overhead that really check all the boxes.

Right now, the most up to date GFS with known PS position shows elements that would be problematic for the Mosaic floe, just not at very low wind speed.

Best practice with nullschool is to embed the url and popup in the image itself which just takes a couple of clicks past the screenshot.

As we've seen, not a day goes by without some apparent rearrangement of the recently formed ice jumble of the Ice Camp. Some of this may be attributable to satellite viewing angle or changing surface salinity rather than actual ice movement.

Pressure ridges and open leads are not always within satellite resolution. For example, a 10 cm crack and slight shear that took down the met tower guy wire is not observable on Sentinel.

Further, we don't know anything about current sensitivity -- is the floe so damaged now that it is preconditioned to the point that minor ice stress now has an effect?

Sometimes obscure changes at the Ice Camp cause major damage while major upheavals might not actually affect experimental areas. I wonder how much those onboard know about real time floe distortion away from the ship -- we are too high but they are too low for a good view.

They have done two fly-overs with lidar that we know of; only one was released but with flattened overlays. Otherwise it is dark and no one is allowed off the safety perimeter, all the more so since it had to be linearized.

While the ship does have forward-looking ice radar on the bridge, being moored on the starboard side with the Ice Camp at right angles and more to the ship axis may block a full assessment. In any event, none of that radar has been streamed our way despite the ship's fast internet. Mostly they are concerned with continuity of data collection.

That hasn't been great to date despite incredible efforts to keep instruments up and running.

Secondarily, they are concerned about evolution of a single floe over a year. That is already off the table as an attainable objective.
« Last Edit: December 07, 2019, 07:02:03 PM by A-Team »

uniquorn

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Re: MOSAiC news
« Reply #384 on: December 08, 2019, 11:53:06 AM »
Drift update.

blumenkraft

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Re: MOSAiC news
« Reply #385 on: December 08, 2019, 02:45:14 PM »
Translation of the Arctic Drift Podcast #8 - (Nach dem Sturm)  After the Storm
Release Date: 06 Dec 2019

<Narrator>

Arctic Drift, the audio log book.

<Markus Rex>

In the last weeks, we've made some circles around here. We moved north, south, west, and east but netted not much way. At the moment we are on the move towards north-east which we like. This puts us back towards the middle of our drift corridor. From here on it will likely, and averaged over weeks, going forward towards the north pole.

<Narrator>

The MOSAIC expedition survived the storm that haunted them last week. In the meantime the infrastructure was rebuild and the scientists can do measurements as usual. The camp is a whole science town on the ice. The different science teams are assigned to different parts of the town. It's like districts. The site expands over several kilometres on the ice around the icebreaker Polarstern.

<Markus Rex>

As you know the hefty storm last week has caused some damage. The layout of our town has changed. Power lines were cut which forced us to switch to power generators causing the measurement equipment to not work fully. But we've built new ways and streets with provisional bridges to reach all the locations safely. We use pulks to overcome smaller cracks. We have reached a certain stability and are back in the game. Also, the 30-meter tall meteorologic mast that fell during the storm will be rebuilt soon.

<Narrator>

The first phase of the expedition has almost concluded, which means that soon the first big swap of science personal and material will happen. Many of the scientists that are on the Polarstern since the end of September will leave the ship, new crew members will come aboard. At the moment icebreaker still can do the job of supporting the ship and swap people.

<Markus Rex>

The members of the first phase of the expedition will soon go home and a new team arrives. This happens via the Russian icebreaker Dranitsyn which left Tromsø on 27th of Nov. They had to wait out a storm on the northern coast of Norway though. Tomorrow night they are expected to leave their fjord. Travel time for them will be around ten days. The exchange of freight will take a few days and then they will already be on their way back.

<Narrator>

In the future such swaps have to be done via aeroplane. The ice is getting thicker by the day and soon no ship will be able to reach them. In the next week, a runway will be built.

<Markus Rex>

For the first time, the ice has reached a kind of stability that you can consider building a runaway on it. The focus is on smaller planes right now so that you can evacuate people should there be a medical emergency. I checked the ice today and i think i found a suitable location. I think we will have an emergency runaway very soon. In the spring we will build it so that even bigger planes like an Antonov can land normally and not only with skis.

<Narrator>

Wintertime in the Arctic doesn't only show in the growing ice thickness. While you see a lot of animals in the summertime, during the winter you only see them infrequently.

<Markus Rex>

The central Arctic in winter is a rather lifeless region. Normally, when you are on an expedition to the Arctic ice, you are seeing plenty of species. You see birds in the sky and seals on the ice all around in both of the Arctic regions. But now, here in the central Arctic during winter it's actually dead. Over weeks we don't see any animal and the ones we see are polar bears. But just recently a very cute polar fox with his black button eyes, white fur and that bushy tale came by, inspected things nervously but then quickly moved on.  It's not clear what their diet is. Often time polar foxes follow polar bear and nourish from what their friends left behind. Of course, we watched out for the foxes big bear friend but we couldn't see any. And since the fox was gone so quickly we assumed he followed his friend to not lose him.

<Narrator>

In the next episode, you'll learn when the next crew members will come on board and who the next navigational chief is.



* blumenkraft is handing over the baton to Psymmo :)



Refugees welcome

A-Team

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Re: MOSAiC news
« Reply #386 on: December 08, 2019, 08:50:43 PM »
This :) was written on Nov 27th but dated Dec 6th and does not address the most damaging storm of the trip on 03-06 Dec 2019. Pulks are sleds being used along with wooden palettes to bridge small leads. Presseisrücken are pressure ridges.

Co-leader Shupe is now over two weeks overdue on his weekly blog. Cires is not blogging the storm, Helmholtz quit in mid-October. Not substantive use is being made of twitter.

No news is a variant on fake news and historical revisionism: if they don't report the Dec 6th storm, it didn't happen. (Those satellites are sooooo annoying: 4 S1AB scenes today + clear Terra Modis.)

Quote
we will have an emergency runaway very soon. In the spring we will build it so that even bigger planes like an Antonov can land normally and not only with skis.
I sincerely doubt this looking at increasingly disheveled Mosaic floe which has not stabilized since the Dec 6th storm. Rex doesn't indicate where this runway will be located nor how thick the ice is; in the original plans, this was to be bladed by Piston Bullies in the flat dark areas (former melt ponds). However Mother Nature got there first.

If he is looking for volunteers to drive the bulldozers out on thin ice, like at Borneo, i am opting out. Surely Rex knows how slowly and unevenly ice thickens in the autumn; if not, a quick look over the ship's 100 mbps internet at the nearby Simb3 ice buoy graphs suffices. Those show 1.254 m snow + ice today -- the ice thickness they expected at mooring on Oct 5th some 66 days ago.

https://www.cryosphereinnovation.com/387850

The Polarstern is looking at five days of inconsequential wind not strong enough to do any more damage. The ship will drift a bit north from its present record of 85.3º N but also a bit east from 121.2º E. We don't know at this point whether the weather will be calm or windy when the relief icebreaker arrives.

The Kapitan Dranitsyn's call sign is UCJP; the other numbers are IMO 7824405 and MMSI 273138300. We will be following the ship closely to see how much unavoidable damage and ridge/lead preconditioning it does in approaching the Polarstern. However it last reported on Dec-03 at 11:30 UTC, meaning it turned off its new state-of-the art navigation beacon after heading up from Murmansk.

This accomplishes nothing for Mosaic because we can still see the ship's stacks and tracks on Sentinel and RAMMB infra-red.

https://www.sailwx.info/shiptrack/shipposition.phtml?call=UCJP

Contrary to their inept static drift model, this is not favorable for reaching wind fields that would bring them towards the Fram Strait. At high latitude, the ship will never get past that gigantic immobile block of MYI documented in the previous post.

The Polarstern is currently 1477 km from Svalbard whereas at mooring on Oct 4th the ship was 1646 km away on Oct 4th. If this rate keeps up (it won't), it would take 579 days drifting on a WGS geodesic (won't happen) to reach Longyearbyen (won't happen in 2020-22).

I've attached the updated archive of S1AB images of the Mosaic floe. In addition to timestamp, rough and precise lat,lon, wind speed, wind direction and ship temperature each entry has direct links to both GFS nullschool and the jp2 image at bslmagb.nerc-bas.ac.uk/iwsviewer/. The former is built out of the preceding variables; the only technical tricks involve nullschool using lon, lat order and rounding odd times down (eg 02:59 to 00:00) which is easily fixed with modular round-off relative to the 3-hour spacings (eg 01:31 to 03:00). That's MROUND(RIGHT(timestamp,4),300) in your spreadsheet.

It's quite feasible to add thumbnails of the Mosaic floe, P-buoy tracks and regional wind the Polarstern is experiencing to each timestamp row in the S1AB database without growing file size too badly. A better alternative might be to make a mp4 at various scales out of every 3-hour nullschool GFS since mooring and flash those that have associated imagery.
« Last Edit: December 09, 2019, 10:39:38 PM by A-Team »

uniquorn

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Re: MOSAiC news
« Reply #387 on: December 08, 2019, 09:41:04 PM »
This ani runs at approximately the speed that it was written. Lat/Lon and distance to 4dp for enthusiasts to check. No coloured lines. Fortunately it's not equilateral so it should be obvious, for now, which distance is which.

Tech note: I think there is still an issue with the animation timing. Some of the distances are very accurate, others are just close. The distance calcs are done separately (finally found mapply) before the ani so I think some frames show distance from an adjoining line of data. Could go back to Octave where there is full control of the ani (but no projection as yet) or investigate other R ani options. Reducing accuracy to 2dp would probably cover it though

hav.dist <- function(long1, lat1, long2, lat2) {
  R <- 6371
  diff.long <- (deg2rad(long2) - deg2rad(long1))
  diff.lat <- (deg2rad(lat2) - deg2rad(lat1))
  a <- sin(diff.lat/2)^2 + cos(deg2rad(lat1)) * cos(deg2rad(lat2)) * sin(diff.long/2)^2
  c <- 2 * asin(min(1, sqrt(a)))
  d = R * c
  return(d)
}

psymmo7

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Re: MOSAiC news
« Reply #388 on: December 08, 2019, 10:38:13 PM »
* blumenkraft is handing over the baton to Psymmo
baton received - waiting for audio log book entry Nr. 9

blumenkraft

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Re: MOSAiC news
« Reply #389 on: December 09, 2019, 06:18:08 PM »
@Psymmo 👍🏽

RAMMB-SLIDER not updating. :(

(Meaning i can't confirm Uniquorn's GIFs ATM so better take them with a grain of salt. </kidding>)
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uniquorn

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Re: MOSAiC news
« Reply #390 on: December 09, 2019, 08:44:15 PM »
drift update. Thanks for the translations.

blumenkraft

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Re: MOSAiC news
« Reply #391 on: December 09, 2019, 08:47:52 PM »
Welcome, Uniquorn. My pleasure. :)
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Jim Hunt

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Re: MOSAiC news
« Reply #392 on: December 09, 2019, 09:02:52 PM »
The Kapitan Dranitsyn..... last reported on Dec-03 at 11:30 UTC.

CruiseMapper reveals the current position of Kapitan Dranitsyn and numerous other icebreakers:

https://www.cruisemapper.com/?imo=7824405

No history seems to be available however.
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

uniquorn

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Re: MOSAiC news
« Reply #393 on: December 09, 2019, 09:45:32 PM »
Thanks Jim, 84.26N108.9, that would put it about here.
edit: widened the area in case it is fast moving.

84.26N108.9
84.33N109.44
84.33N109.6
84.5N113.6
« Last Edit: Today at 10:33:57 AM by uniquorn »

A-Team

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Re: MOSAiC news
« Reply #394 on: December 09, 2019, 11:04:09 PM »
https://www.cruisemapper.com/?imo=7824405

Nice! Note that the GPS is to five decimals, unlike the one that Mosaic shares. Still no history at Sailwx after Dec 3rd. Cruise Mapper only works in certain browsers (such as Mac Chrome but not Mac Opera). Mousing around on the lat,lon bar does move the ship around but the time associated with that move is not shown. What time there is, is "local time" in the middle of nowhere, not utc! That might be either Murmansk or Tromsø.

On a cruise ship, meal times are in local time. The Polarstern also does not keep utc but instead it has been walking it back so as to synch mealtimes when the KD arrives.

This is great that the two ships are already on the same tile at Polarview. I don't see a bright dot yet for the KD but it should be down there. The captain has 35 years of icebreaker experience so is no doubt taking the easiest route.

GFS shows good weather for the rendezvous, the first real break Mosaic has had. No way could they transfer all that diesel with km wide leads opening and closing. The Polarstern is moving north somewhat left of the wind which may be attributable the deflection by the massive ice pack and fixed CAA islands ahead.
« Last Edit: Today at 02:57:25 AM by A-Team »

uniquorn

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Re: MOSAiC news
« Reply #395 on: Today at 10:45:31 AM »
A bit easier to spot KD today.

A-Team

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Re: MOSAiC news
« Reply #396 on: Today at 11:50:39 AM »
Nice spotting. It is on all three Polarstern S1AB today, including the PolarView plug in with its precision lat lon mouse-over.

Rendezvous weather five days out remains bland. The Polarstern will be more or less in the same position it is now. The personnel there now will have ample time to have equipment deployed on the ice brought back into working order before turnover (to the extent that's possible).

http://bslmagb.nerc-bas.ac.uk/iwsviewer/?image=DataPolarview/111_S1jpeg2000_201912/S1A_EW_GRDM_1SDH_20191210T040827_2F21_N_1.8bit.jp2   

https://earth.nullschool.net/#2019/12/10/0300Z/wind/isobaric/1000hPa/orthographic=-45.00,90.00,1100/loc=120.9,86.5
« Last Edit: Today at 12:43:06 PM by A-Team »

JayW

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Re: MOSAiC news
« Reply #397 on: Today at 11:54:36 AM »
RAMMB-SLIDER not updating. :(

Updating again, you can see the icebreaker KD approaching in this shot.
Click to run.
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A-Team

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Re: MOSAiC news
« Reply #398 on: Today at 12:58:55 PM »
The white dot seems to be in the wrong location(?). The KD is not preceding due north as shown but rather mostly east.