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Messages - uniquorn

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Some people have good use for the updated regional data files.


The gridded velocity data was not updated (yet?), so Fram export graph cannot be updated.

Here are the volume and volume and volume-anomaly graphs. Colors have been a bit tweaked, a light grey background added to make the yellows a bit readable, and shared with existing area/extent graphs.

[edit: gave 2020 a thicker line as suggested by charles_oil]

PIOMAS has updated the gridded thickness data upto the 15th. Calculated volume at 2020-2-15 was 19.67 [1000km3], This is fifth lowest for the day, exactly the same as the volume on that day in 2016, the "final official" volume data may change that exact match.

Here is the animation for February so far.

Arctic sea ice / Re: Latest PIOMAS update (February 2020)
« on: February 04, 2020, 08:19:07 PM »
Here are volume and volume-anomaly graphs.

It is getting harder to find a new color for a new year. I am trying a new color scheme that I found here:

Have a look, I am not sure myself yet, comments are welcome.

Arctic sea ice / Re: Latest PIOMAS update (February 2020)
« on: February 04, 2020, 07:21:45 PM »
Thickness map on 2020-01-31, compared with recent years and the diff's. Click for full size.

Arctic sea ice / Re: Latest PIOMAS update (February 2020)
« on: February 04, 2020, 07:11:15 PM »
PIOMAS has updated. Volume on 31st January was 18.282[1000km3], this is fifth lowest behind 2011,2013,2017 and 2018.

Here is the animation.

Arctic sea ice / Re: Arctic Ocean salinity, temperature and waves
« on: January 25, 2020, 11:48:22 PM »
Worth the read.
"We conclude that tidal shear stresses at the bottom and the ice‐ocean interface facilitate the transport of warmer and saltier AW to the surface layers, while the effects of tides along the Siberian shelf result in mixing of fresh river runoff waters with saltier water below the eroding halocline. Mixed layers, being much thicker due to the effects of the critical latitude on the clockwise component of tidal currents, entrain saltier waters to the surface boundary layers. Along the Siberian coast with strong river runoff, thicker boundary layers result in mixing in halocline and penetration of freshened waters to depth. Finally we find that, in this particular model, tides are responsible for ∼15% of the ice volume reduction and the presence of more salt waters at the surface in average by ∼1–1.7 PSU (Figure 14). Tides significantly modify the freshwater pathways along the Siberian shelf, resulting in saltier water along the Greenland coast. Tides affect the fresh water and heat content in the AO, with a reduction in the former by 7% in the upper 100 m"

Arctic sea ice / Re: Latest PIOMAS update (January 2020)
« on: January 04, 2020, 10:09:31 AM »
Thickness map on 31st December 2019, compared with recent years and their diffs.
Clicks are needed for full size.

Arctic sea ice / Re: Latest PIOMAS update (January 2020)
« on: January 04, 2020, 10:02:35 AM »
Updated Fram volume export.

Arctic sea ice / Re: Latest PIOMAS update (January 2020)
« on: January 04, 2020, 09:59:48 AM »
Here are the updated volume and volume-anomaly graphs. Click for full size.

Arctic sea ice / Re: Latest PIOMAS update (January 2020)
« on: January 04, 2020, 09:31:31 AM »
PIOMAS gridded thickness data was update. On the last day, 31st December, volume is calculated to be 14.52 [1000km3], which is fourth lowest behind 2016, 2012 and 2017.

Here is the December animation.

Arctic sea ice / Re: Latest PIOMAS update (December 2019 )
« on: December 04, 2019, 11:45:22 AM »
The Fram-volume export graph. Average export was low, compared with average November export.

Arctic sea ice / Re: Latest PIOMAS update (December 2019 )
« on: December 04, 2019, 11:39:10 AM »
Updated volume and volume-anomaly graphs. Click for the better picture.

Arctic sea ice / Re: Latest PIOMAS update (December 2019 )
« on: December 04, 2019, 11:29:36 AM »
PIOMAS has upgraded the gridded thickness data. Last date, 30th Nov, the calculated volume was 10.35[1000km3]. That is third lowest for the day (behind 2016 and 2012).

Here is the animation for November 2019.

Some people have use for the updated regional data files:


Fram volume export. Big negative spike on the last day can be seen in the animation above.

Updated volume and volume-anomaly graphs.

PIOMAS has upgraded its gridded thickness data upto 15th November. Calculated volume at that date was 8.54 [1000km3], which is third lowest behind 2012 and 2016.

Here is the animation of the first half of November.

Arctic sea ice / Re: Latest PIOMAS update (November 2019)
« on: November 04, 2019, 09:42:14 AM »
Thickness map, comparisons with previous years and their diff's. Click for full size.

Arctic sea ice / Re: Latest PIOMAS update (November 2019)
« on: November 04, 2019, 09:35:13 AM »
Update Fram volume export graph. The export is increasing, not quite as fast as expected.

Arctic sea ice / Re: Latest PIOMAS update (November 2019)
« on: November 04, 2019, 09:30:19 AM »
Update volume and volume-anomaly graphs. 2012, 2016 and 2019 are very close.

Arctic sea ice / Re: Latest PIOMAS update (November 2019)
« on: November 04, 2019, 09:20:44 AM »
PIOMAS gridded thickness data has updated. Volume calculated from thickness was 6.52[1000km3] on 31st October, third lowest for the day. 2012 and 2016 had a lower volume.

Here is the animation.

I think I took a wrong turn somewhere & ended up in a thread about corn?

Some people have use for the updated regional data files:


Fram volume export is still summer-low.

Updated volume and volume-anomaly graphs.

PIOMAS has updated the gridded thickness data up to 15 October. Volume was 5.16 [1000km3], second lowest (after 2012) for the day.

Here is the animation for October thus far.

Thank you all for not just laughing at me.  Although it is kind of funny.  What I have posted on this thread is truly thrown together by a completely unqualified researcher in full batshit mode.  There will be a more thorough and thoughtful write up, in time.

Operating theory is "we are in a runaway abrupt climate flip" and I want to disprove it to myself, but bear it in mind that I am completely unconstrained in my thinking & language.  Full power Dunning-Kruger.  This is from a lone mind bent on survival.  I don't have any allegiance or hesitancy based on academic norms.

I managed to click on the running mean AO index from 1950-present over here

Added Paint.exe black line connecting the Jan 1 position for the last couple of years.  It would seem reasonable to guess that the AO index will be hovering around neutral on Jan 1 2020.

Arctic sea ice / Re: MOSAiC news
« on: October 11, 2019, 01:47:19 PM »
Animations of buoys drift speed attached, code on my github, it should be possible to take a set of buoys and calculate their movements respective of each other.. interesting idea

there's accelometer data in the buoy data as well, I assume this can be related to wave height or ice bits bumping into each other?

Also if anyone has good data files for ice concentration/movements please let me know. I saw AMSR2 has hdf files but they're a bit of a pain, preferably something with coordinates.

Arctic sea ice / Re: MOSAiC news
« on: October 11, 2019, 12:16:54 PM »
WV graticule? need final set of buoys? buoys too near the Polarstern? Physics of materials?
Spectacular VIIRS above ... but when I went to the link, it had been over-written by something unrecognizable. That happens all the time at WV as swath updates roll in. I suppose the bright networks of veins are leads (resp. thin ice) with warmer water showing through. These might be worth mapping as lead openings are recurrent weaknesses.

The 43 page explainer for the Visible Infrared Imaging Radiometer Suite is here:

WorldView doesn't do graticules well, 80º is the first latitude out from the pole with 30º increments on longitudes. Better if NASA provided options for controlling the OpenStreetMap vector graticule and fixed code so animations captured it. It's possible but inconvenient to capture the timestamp on a per swath basis which is critical to synching with other satellites.

While WV does have very accurate mouse-over lat/lon in the corner, those don't stay tied to a floe after image save or screenshot. Mosaic Multisensor offers a very nice graticule on their higher resolution images (from Oct 7th on).

For WV, if your save includes long lines intersecting the 80º circle, that chord length is enough to accurate rescale AMSR2_Large and capture its graticule as overlay for 75º and 85º plus 1º longitude increments.


The ship itself is one big fancy drift buoy, not only reporting its GPS but also whatever parameters those six containers of atmospheric instruments in the bow are recording. Plus its azimuthal heading which the surface velocity profilers do not provide.

A rigid body can undergo translations (GPS) and rotations (azimuth changes) that are not relevant to the brittle failures of concern (opening and closing of leads, over-rafting of floes, slip-strike shearing and pressure ridges/keels).

Mosaic actually likes leads because they release ocean heat to the atmosphere and are important to study for overall energy flows, just not leads that cut LAN and power lines and strand personnel at field stations.

Taking any three buoys that define a good triangle (not co-linear, no overly acute angles), the lengths of the three sides and area enclosed do not change over time in a rigid ice pack. If the area increases, it means leads have opened under extensional forces; if the area decreases, compressional collapses have occurred.

If say 70 buoys are deployed, a goodly system of coupled triangles (the perimeter being the convex hull) emerges for monitoring regional ice deformation. Here ice brittleness increases non-linearly with colder temperatures. Since the SVPs record air temperatures at the ice surface and since the seawater underneath the ice is clamped to -1.7ºC, the temperature profile through say 2m of ice can be estimated.

Mosaic has two different buoy scales, high resolution local on and around the chosen floe and more sparsely regional. There aren't enough buoys out there to do the whole basin. There has been talk of large-scale air drops of passive devices like radar corner reflectors that would show up as points of light on Ascat etc. Hasn't happened.

Someone posted a great animation (can't relocate :() of the ice temperature profile behavior under an upper sinusoidal (seasonal) boundary conditions, plus an explicit solution of the governing heat equation. Thus if the a curve is fitted to the buoy's hourly temperatures, each term in its fourier expansion will have an exact solution -- and these are additive solutions.

However real ice has many issues such as surface snow and its complex aging status, frozen-in air bubbles, variable salinity inclusions, brine pockets, crystal dislocations, adherent algae and copepods etc etc meaning that the heat conductivity parameter isn't constant or known. So it is easier just to freeze in a string of thermistors below the buoy.


We can do a lot better than that cramped meereisportal visual just with a drag-n-drop of all the buoy lat/lon columns onto google earth pro. The advantage of GEP is the liquid rescaling to any zoom, a free parameter for temperature or thickness and mouse-over popups; the disadvantage is there does not seem to be a digitized daily ice edge line around. However there is a way of auto-generating that from say the AMSR2 blue edge.

GEP barely pauses loading a kml file with 250,000 lat/lon waypoints. That would be 30 buoys reporting hourly for a year. Hourly is a bit much given slow drift speeds but it is great for dynamic triangles. There is very little overhead to drawing lines between buoy pairs with the same timestamp.


The AMSR2 images below compare the ice edges on the Siberian side south of the Polarstern on Oct 10th for 2013-2019 (the 2012 is not provided by the UHH archive). The large format 3.125 km does notably better on growing landfast ice. This narrow strip is difficult to image because of the irregular coastline can occupy part of rectangular gridded pixels.

Clearly autumn 2019 is off to a very slow start; the magenta overlay line on earlier years shows how much open water is still left in the Laptev, the star at bottom shows the Polarstern location. I don't expect the 500 km reach of open water to freeze over any time soon because shallow shelf water been increasingly affected by Atlantification. The Laptev had frozen over completely in 2012-13 by the first of the year.

Developers Corner / Re: Test space
« on: October 09, 2019, 02:16:29 PM »
Salinity data needs to be taken from the dat files and added to the data frame first,
 tdata$salinity <- as.numeric(txdata$Salinity)
in the .dat import loop, same place temperature is added, then replace color = ~tempC with color = ~salinity in the plotly setup (it takes columns from the data frame specified at the start)

One problem I'm running into is that you can only use one colorscale per plot, still trying to hack my way around that, until then not sure how to display both data, maybe as circle lines, or offset slightly in one direction to make a two sided curtain..

I made the bathy work on ITP 116 which is floating around the north pole and just crossing the Lomonosov ridge, you can see the buoy got stuck for a while in spot where there's an almost 2km vertical cliff / cutout in the ridge. Takes a bit to load but worth it: (hover over a bathy point to see depth in meters, not to z-axis scale..)

Arctic sea ice / Re: The 2019/2020 freezing season
« on: October 09, 2019, 01:52:51 PM »
I'm surprised the extent numbers are low after yesterday's polar crossing waft ripped the ice apart, polar view 8 to 9 oct around 100°E / 84-87°N approximately overlapped (click to play)

Dr. Judah Cohen at the AER Risk Assessment has identified a coupling of tropospheric and stratospheric polar lows, looking forward about 10 days time.  This would create a proper basin in atmospheric heights over the Arctic for a positive arctic oscillation mode, with a slightly less "wavy" jet stream, or at least one that isn't dissolving as much

This forecast is an improvement and it would, for the first time, interrupt the 5 straight months of high anomalies over vast reaches of the Arctic.  We would get less severe weather, and I think zonal flow would start to strengthen.

It was famously predicted, here in this thread, that there will be jet streams at the north pole 4 times, 8 days apart.  I didn't want to predict anything because of how much of a complete nonsense Dunning Kruger I am on this, but I went down the rabbit hole to see for myself, so might as well see what it's worth.
2018/2019 was a cold winter on this chart, never expected it to be so well behaved again?

Well what have I heard a dozen times?  That the recovery enables the big anomaly.  A big melt year will be preceded by a recovery year.

In systems thinking you could also identify a return to normal right before an outright crash.  Resistance right at the breaking point.

What I do, is just like... we could be experiencing mixed modes of ice age inter-glacial vs. Eocene Hothouse and be losing angular momentum as a result.  That would, complete wild guess, be a feedback that is not assessed.  Climate models are tested for retained atmospheric angular momentum, because it is a value that is assumed to be conserved in our future.  Well if there's this much mixing, where's the friction?  Adiabatic heating and wave interference along with heavier storm bursts.  Raising the tropopause 15 meters worldwide was a really bad idea.  It allows waves from the tropics to cross over the north pole.

So I am extremely interested in how this forecast plays out.  I want to be wrong about there being perpetual splashes of jet stream across the Arctic four or eight days apart, making it look like the whole atmosphere is stalling. 

It never should have lasted this long.  Since May 1 2019.  I thought it would not have lasted this long, but stratospheric polar vortex was always gonna stomp all over this thing in the end.  There will be a stratospheric PV formation just like every winter.  It will catch a wave and begin to pinball around the Arctic in November, and it will experience a messy destruction in January or February with cruel cold Arctic outbreaks in the Upper Plains & Great Lakes, and this will be completely normal and boring compared to the past five months of 2019.

I know some predictive tools have been bullish on a very strong polar vortex signal with definite AO+ NAO+ going back 6 weeks.  Now it's showing up in the weather models.

If this is coming true, then there will not be a large heat anomaly and accompanying jet stream ridge breaking off into a cut off high in the vicinity of the North Pole on October 16-18 and there is hope for a real change in the pattern.

and if not*, I will bug out early, see you in Patagonia where we will eat beavers and wait for land to open up in Antarctica

I will be watching the ocean heat anomalies

I will be watching the polar cap height FOR SOME BLUE

The AO index and predictability:

And I will be watching very closely for evidence we aren't bleeding AAM like we're dying

Developers Corner / Re: Dev library
« on: October 07, 2019, 12:15:30 AM »
hmm doesn't sound like you're seeing what I see, only tested with chrome, less then GB mem use & 20 secs loading or so, data download should only be 10MB.

The controls are supposed to let you pan/zoom/orbit the thing

Sample of ITP116 attached (one of the nicest)

Developers Corner / Re: Dev library
« on: October 06, 2019, 10:54:16 PM »
In the spirit of sharing I stole the genius of the best libraries around.. plotly does more than I could have dreamed of and exports to WebGL, takes some time to load but worth it :D

Smallest example:
check the rest on, the biggest ones have crashed my browser on occasion, would like to hear how it works for other people. Could optimize with averaging some data points if needed or other 'd0h' moments.

code updated on much quicker and awesome

Arctic sea ice / Re: MOSAiC news
« on: October 06, 2019, 02:24:20 PM »
Below are some floe tracking images that tie precise lat/lon positions into the WorldView visible dates when floes are more intuitively portrayed in clear weather. The first provides 16 days of daily displacements of the PS Floe based on their archived mix of radar images. Based on a fairly strong anticyclonic OsiSaf today, I expect Floe movement to the 'right' overnight.

The Floe is embedded in a larger context that moves as a semi-rigid block; indeed the whole ice pack is still exhibiting coherence but daily morphological plasticity as can be seen in the translucent greenish animation from earlier in Sept. (Ascat arrives as grayscale but two other channels for color can be made from fourier bandpass filtering that emphasize different scales of contrast variability.)

Sentinel imagery that Uniq has been posting is far higher quality but involves handling large initial files in unpopular jp2 format. The 16bit depth provides much more latitude in contrast adjustment though the gains are not as phenomenal as with 8bit Ascat. At the end of the day, everything has to be posted in 8bit x 3.

In the file names, 20191004T064336 parses out to 2019 Oct 04 at UTC time 06:43.36. The two images are then 06:27 - 06:43 apart or 16 minutes short of 48 hours, critical to accurate measurement of floe motion. It's possible to make 'interferometric' color images from just two frames in ImageJ; these have excellent prospects for displaying deformation over the whole region. As always we are very dependent on satellite providers for spot-on pixel geo-registration.


The dark blob in the center corresponds to the ice oddity in the first image of #77. It has stood out for since last autumn out as a relatively white region in plain Ascat; it is one of the last regions of thick MYI; it barely experienced TPD last winter.

The third image illustrates tracking of an unrelated floe in Modis Terra. Note daily or better coverage is needed to define motion as the 'shortcut' shown does not capture details of multi-day motion.

The fourth image shows the all-weather forward view from the bridge. The dark triangle is aft. While the floe shapes seems terribly distorted, publications have used it in the past to measure floe jostling and ice deformation. This clip is from an earlier voyage. The PS may have it turned on while moored but is not uploading it to a public archive as far as I know. ship radar N-ICE2015

Arctic sea ice / Re: Latest PIOMAS update (October 2019)
« on: October 06, 2019, 10:38:20 AM »
Finally a linear trend. The 2019 data point lies near perfect on the trend line. That means that the zero ice extrapolation has not shifted either and stays at 2032. That, and the fact that is has not changed much for many years gives some confidence to this date.

So for comparison I have added the same graph that I posted in 2012: also a 2032 zero ice extrapolation. The 'prediction' for 2019 is spot-on.

Arctic sea ice / Re: Latest PIOMAS update (October 2019)
« on: October 06, 2019, 10:29:10 AM »
Same as the previous but now a Gompertz regression, preferred by some. The Gompertz function approaches but never reaches zero, but still the same postponement to later and later dates is clear.

Arctic sea ice / Re: Latest PIOMAS update (October 2019)
« on: October 06, 2019, 10:15:12 AM »
Here is the exponential fit. The 2019 minimum is above the trend, shifting the extrapolated zero ice after  2025 where with only data up to 2018 it was 2014.

Arctic sea ice / Re: Latest PIOMAS update (October 2019)
« on: October 06, 2019, 09:57:04 AM »
Continuing with the graphs...

Here is the updated Fram volume export graph. September export was below normal.

Arctic sea ice / Re: MOSAiC news
« on: October 05, 2019, 10:05:14 PM »
Right, the big issue now is how fast the Polarstern's safety zone will grow to the south (towards New Siberian Islands). A buffer for long reach swells would really improve their situation, as would solidified adjacent ice.

Sept 2019 is an especially unfavorable for late open water/slush in the northern Laptev mooring area as the PS team is well aware (3rd and 4th graphics). The latter appends Oct 2018, though that scarcely provides a prediction for this autumn.

I found some trackable features for Oct 04 back to Sep 21 enveloping the Chosen Floe (which itself is not so trackable) and was able to follow them back into Modis/Worldview daylight. The ice has been going around in an aimless circles with no sign of TransPolar Drift onset. Despite leads opening and closing, this region of ice has been moving mostly like a rigid block.

Last May, we found the best way to quantify deformation was via Delaunay triangulation. That is, if three features form a triangle, its changing lengths and angles -- whose values ImageJ conveniently tabulates in CSV -- describe ice deformation since triangles unlike quadrilaterals etc are rigid. This method was used in a recent N-ICE2015 article for the same purpose.

Sentinel-1 does not fly over every day by any means. They seem to be using other sources of imagery in a mix-and-match manner. For example, Sept 25th is a just an exact copy of Sept 26th in the region shown.

The satellite usage table below from Mosaic's main planning document shows the options (needs a click to be readable; color legend is screwed up). Naturally, they have a budge gto buy commercial coverage as needed.

Arctic sea ice / Re: Latest PIOMAS update (October 2019)
« on: October 05, 2019, 09:13:14 AM »
More graphs to prepare (the ones with annual minimum), but that will be much later. Paint job to do.

Arctic sea ice / Re: Latest PIOMAS update (October 2019)
« on: October 05, 2019, 09:04:04 AM »
The volume and volume-anomaly graphs.

Arctic sea ice / Re: Latest PIOMAS update (October 2019)
« on: October 05, 2019, 08:57:45 AM »
PIOMAS gridded thickness data has updated. Volume calculated from thickness was 4.57[1000km3] on 30th September, second lowest for the day.
The 2019 minimum was around the 10th, 4.06[1000km3]. As these number are not exactly the same as the official PIOMAS volume numbers, wait for the release of those.

Here is the animation.

Here are the updated volume and volume-anomaly graphs. Click to enlarge.

The PIOMAS gridded thickness data was updated to the 15th of September. Volume (calculated from thickness) on that date was 4.06 [1000km3], second lowest for the day. The number  have been nearly constant at 4.05-4.06 for several days. Because my calculation sometimes differ with the official volume data by 0.01 I do not know if we have reached the minimum (my feeling is, it has).

Here is the animation of September thus far. 

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