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Author Topic: DATA HEAVY MP4 ANIMATIONS A year in the life of SIMB3 443910  (Read 694 times)

uniquorn

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DATA HEAVY MP4 ANIMATIONS A year in the life of SIMB3 443910
« on: October 03, 2021, 07:52:18 PM »
A year in the life of SIMB3 443910  15MB
scale -79.1C to +55C
« Last Edit: October 05, 2021, 02:44:46 PM by uniquorn »

Tor Bejnar

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Re: DATA HEAVY MP4 ANIMATIONS A year in the life of SIMB3 443910
« Reply #1 on: October 05, 2021, 04:33:31 PM »
Very interesting!  Wind seemed to be a dominating force only occasionally.
Arctic ice is healthy for children and other living things because "we cannot negotiate with the melting point of ice"

uniquorn

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Re: DATA HEAVY MP4 ANIMATIONS A year in the life of SIMB3 443910
« Reply #2 on: October 05, 2021, 07:45:44 PM »
Wind effect might be obscured by the resolution and the nullschool location circle. This gif shows more drift detail.  5.4MB

A-Team

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Re: DATA HEAVY MP4 ANIMATIONS A year in the life of SIMB3 443910
« Reply #3 on: October 07, 2021, 04:59:20 PM »
Quote
The answer is blowing in the wind?
Uniq's two products above represent significant advances in time series presentations, unavoidably at the price of a bump in file size if locational and time resolution in the graphics are to keep pace with the quality of buoy data.

The drift gif is very different from the weather/temperature in that its bathymetric background is strongly binned to 3-bit and identical for all 2250 frames except for the thin velocity track. This favors gif's compression which  is mainly just differencing of consecutive frames (leaving one new velocity dot).

That and large frame number do not favor mp4 so much because the 256 distinct track colors occupy a negligible percentage of total pixels (though could be binned to say5-bit). Note file size could be reduced by dropping from 1200 pixels down to 800 (or even 600) by making the track somewhat thicker at the price of resolution loss in location. However the 2250 frames pushes the limits on common desktop graphic cards.

The recognizable land reference here is Banks Island. It is 45º CW from 'Greenland down' or 90º from Greenwich meridian. A small Arctic Ocean locator in the corner would not increase file size. The issue here is how to present say 'five years in the life of a buoy series' while maintaining realistic accessibility.

The wind acts globally, simultaneously and inconsistently on the whole ice pack, meaning an individual frozen-in floe is not at liberty to respond independently or instantly to the ever-changing local wind force field applied to it.

The ice pack (or 100 km floe) has significant inertia and physical connectivity and can only move compatibly with those. In terms of momentum transfer, the wind ‘catches’ very unequally across the ice depending on ridges and edges and their orientation.

The applied wind force changes over a much shorter time frame than ice movement: just as it begins to respond, the wind changes direction and speed. So somehow the nullschool display needs a time-averaged wind field over whole pack, plus unavailable surface friction and under-ice currents.

The resultant of all this is provided by OsiSaf. However OsiSaf is incapable of tracking the buoy's overall trajectory because there's no good way of combining consecutive gridded two-days, meaning errors would overwhelm accuracy over a week, not to mention a full year.

Ascat ice pack motion for this same year was recently posted but as an mp4 as the gif had was well over 100 MB in size. The image below shows bathymetric depths replaced by day 277 of Ascat with the final day of buoy motion as overlay. Smos/Smap or AWI concentration could also be used.

It would be quite challenging to do this for a full year short of a gigantic file size (or small image dimensions) -- no problem on one desktop but no way to distribute to the forum.

The observed detail in buoy movement is very instructive -- especially the many aimless shifts in direction. The track does not look that different from a random walk -- proof that nothing resembling an ice gyre took place over the year.

The buoy only made one brief excursion out of the abysmal depths so it seems implausible that tides, near-inertial forces, or coastal currents contributed to its motion. Given the state of the ice pack, its motion is entirely attributable to the wind.

The second image shows open water in blue and AWI leads of 07 Oct 2021 in conjunction with the year-long buoy track and Beaufort bathymetry.

While the buoy drift time series is very worthwhile -- the suspense makes the viewers realize they have no idea whatsoever what it will do next -- that motion at these locations may be a lot less constrained during ice season. 

Thus as a compromise to a daily satellite image underneath and massive file, that image might only need to change monthly or so. It is feasible to show Modis visible as the cutout, either entirely, in areas of interest, or just in a circle about current buoy position.
« Last Edit: October 07, 2021, 09:49:20 PM by A-Team »

uniquorn

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Re: DATA HEAVY MP4 ANIMATIONS A year in the life of SIMB3 443910
« Reply #4 on: October 08, 2021, 12:17:47 AM »
Some good ideas there though my head is deep into water temps at the moment. Here is a better look at whoi itp121 since deployment.
https://www2.whoi.edu/site/itp/data/active-systems/itp121/

Very similar time period so the weather is roughly the same but the starting point makes a huge difference. Looks a bit like a gyre  ;)
itp120 is co-located with 443910 above, edit: only reports at 00 and 06hrs so ani is not so smooth. The rawlocs file has over 18000 entries and would need sorting

Cross posting 7m to 24m temps (-1.55C to -1.0C)
« Last Edit: October 08, 2021, 10:46:19 AM by uniquorn »

uniquorn

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Re: DATA HEAVY MP4 ANIMATIONS A year in the life of SIMB3 443910
« Reply #5 on: October 29, 2021, 02:46:43 PM »
A year in the life of SIMB3 443910  15MB
scale -79.1C to +55C

Adding a thickness update to go with the weather. 443910 has survived while most of the ice didn't. Started the freezing season at around 90cm thick, then thickens to ~180cm over the freezing season, then almost melts out completely.
Now ridging back to roughly 25cm (ignoring the large swings in surface measurements)

Added thickness vs pressure as a reminder of the wild swing from 1070.8 to 992.8hPa
« Last Edit: October 29, 2021, 04:33:31 PM by uniquorn »

uniquorn

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Re: DATA HEAVY MP4 ANIMATIONS A year in the life of SIMB3 443910
« Reply #6 on: November 07, 2021, 03:13:12 PM »
mercator modelled salinity at 34m depth, sep2018-nov2021 (5MB)

uniquorn

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Re: DATA HEAVY MP4 ANIMATIONS A year in the life of SIMB3 443910
« Reply #7 on: November 07, 2021, 05:00:08 PM »
same thing as above with gmrt bathymetry overlaid at 21%. Mostly looking at the modelled effect of Gakkel ridge on incoming atlantic water for itp129  (5.3MB)
« Last Edit: November 07, 2021, 05:14:21 PM by uniquorn »

uniquorn

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Re: DATA HEAVY MP4 ANIMATIONS A year in the life of SIMB3 443910
« Reply #8 on: December 03, 2021, 03:22:42 PM »
Rammb of ice drift north of FJL/Svalbard, nov24-dec2, every 51min. 3.7MB

Shows the effects of wind, the warmer water of the WSC and tidal induced 'turbulence' near the shelf break.