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Messages - johnm33

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1
Arctic sea ice / Re: The 2020 melting season
« on: Today at 02:38:04 AM »
Here is Hycom thickness

2
Arctic sea ice / Re: The 2020 melting season
« on: July 10, 2020, 06:10:09 PM »
RE: #2478 bathymetry

3
Arctic sea ice / Re: The 2020 melting season
« on: July 08, 2020, 10:57:50 PM »
The graph below is a projection of the 2020 NSIDC daily sea ice extent, based on the daily losses since 2000, with the oldest years being lighter grey lines and most recent being darker gray. The years with the lowest minima are coloured. It also includes the date and value of all previous daily minima in circles.
Based on the projections it appears almost certain now that we'll finish in the bottom 6, but will still require and one of the largest losses on record to beat 2012. This is, of course, ignoring the conditioning of the pack, low volume and the continued forecast for high pressure.

4
Arctic sea ice / Re: The 2020 melting season
« on: July 02, 2020, 06:34:20 PM »
In case anyone is interested in an on-the-ground perspective on this year's melting season, I put together a time-lapse video using still images from the observatory's webcam here in Alert.  The video covers 12 days from June 18-30, which includes the record-breaking June high temperature of 18.6°C recorded on the 28th.


5
Arctic sea ice / Re: HYCOM
« on: June 28, 2020, 08:46:10 PM »
If I may add, the ice distribution in Hycom is very weird, with all the thick ice up to 5m bunched very near to Greenland and the CAA, and the rest of the CAB at a measly 2-2.5m. I find it very hard to believe this represent a true gradient, and Cryosat-SMOS does not support this either.

It now occurs to me that an ASCAT animation, showing where the old ice is and covering the period leading up to mid-April, could be very useful here as well. There should some animations available that uniquorn has posted through the winter and spring, will look for a suitable one.
Perhaps we should remember that smos has a 40km grid resolution, and cryosat cannot resolve leads and ridges below a scale of 200-300m. It is unlikely that smos is contributing in the area you reference anyway as it is good at sub 1 m thickness, whole cryosat is better when ice is thicker than that.
So cryosat may assume ridge fields tops as continuous freeboard when things are far more complex at scales below Its resolution. A pity both are confounded during melt season, smos by wet ice, and cryosat by atmospheric moisture, especially cloud and fog, snow, particularly with melted and refrozen layers can cause both to oberestimate freeboard also.

Overall I am fairly impressed by the match between Hycom and crysmos in the april comparison. I am not sure why you find it so weird that the thickest ice is where it gets crushed and stacked by drift pressure against these coastlines, where also it experiences the coldest, with Katabatic winds dropping off tall ice sheets and mountains in midwinter?
At the end i guess, probably the truth may be somewhere in the middle. With unknown it is good I think to keep minds open to All informations, and individuals must balance how many "grains of salt" should each source be taken with.  :P

6
Arctic sea ice / Re: The 2020 melting season
« on: June 10, 2020, 09:16:20 PM »
quantifying the effects of mixing on melting?  ;)

Here is an overlay of uni-hamburg amsr2-uhh concentration onto gmrt bathymetry from jun3-9.
First to note is the probable rain highlighting individual floes along the Nansen basin close to Severnaya Zemlya, somewhat masking the already present lower concentration there. Low concentration ice continues around the 'top' of the basin, probably due to upwelling of incoming atlantic water. Keen eyes will also spot more low concentration ice where the basin meets the Lomonosov Ridge, probably also due to upwelling.
In the Kara Sea the low concentration ice above the St Anna trough has been visible since may10

Sea ice concentration has been contrast enhanced a little to allow it to show over the bathy.
0% concentration, normally dark blue, has been set to transparent.

7
Capturing a trillion tonnes of excess CO2 in rock using the power of natural wave energy

https://projectvesta.org/

Project Vesta is a non-profit, founded on Earth Day 2019. Our vision is to help reverse climate change by turning a trillion tonnes of CO2 into rock. We will do this using the power of natural wave energy at green sand beaches. Today, we know that reducing carbon dioxide emissions alone will not be enough to solve the climate crisis: we need to remove carbon dioxide from the atmosphere. Fortunately, nature already has a way, billions of years old, to do this – by weathering volcanic minerals. When rain falls on volcanic rocks and washes them into the ocean, this causes a reaction which removes CO2 from the atmosphere and locks it up in limestone at the bottom of the ocean.

Accelerating a Natural Process

Project Vesta’s approach dramatically accelerates this ancient natural process. We make green-sand beaches with an abundant volcanic mineral, olivine. There, wave action speeds up the carbon dioxide capture process while de-acidifying the ocean. Thirty years of scientific research has demonstrated that this works and has provided strong evidence that it is a highly affordable and scalable solution. The process captures 20 times more carbon dioxide than the extraction and transportation of the olivine. If deployed on just 2% of global shelf seas, could capture 100% of annual human emissions.

An Open-Source Scientific Approach

Our mission is to further the science of enhanced weathering and galvanize global deployment. To that end, we are planning experiments to pilot green-sand beaches. All scientists in the field are welcome to contribute to the design of these experiments, and all are welcome to analyze the resulting data. Once we have finished the experiments and published the data, we will be able to deliver to the world a blueprint and integrated model for deploying green sand beaches. The Enhanced Weathering Integrated Assessment Model (EWIAM) will enable any government or private organization to measurably remove carbon dioxide from the atmosphere at scale.

History - Where We Came From

Project Vesta was born out of a climate change think-tank called Climitigation. This group investigated as many carbon capture solutions as possible, searching for one that had received too little attention and investment. Climitigation found that coastal enhanced weathering was a process with enormous potential for cheap, permanent carbon capture at massive scale. Further, they found that the technology was stuck in the lab, despite real-life beach pilots being the clear next step. No one was bringing together the combination of multidisciplinary science, government support, funding, and sheer force of will that would help this technology ‘cross the chasm’ between theory and maturity. Project Vesta was founded to do exactly this.

The Project Vesta Ethos

We are an open-source project. The work we do will be available to all in service of maximum speed and efficacy of global deployment. We are doing this for the planet, not for ourselves or for any individuals.

We are fundamentalists about our commitment to scientific rigor. We believe that the path to global scale is paved with robust science, transparency, and the credibility that comes from these.

We consider the entire life-cycle of the impacts of our actions. We aim to capture 20 times the CO2 we emit. We measure the ecological effects of our entire process from quarries to marine ecosystems, and wherever possible seek to have a regenerative effect on local ecosystems and communities.

Scale is paramount. Our goal is to remove tens of gigatons of carbon dioxide per year. We believe that to be seriously impactful, CO2 removal solutions must be able to achieve gigaton+ scale by 2030.

Inspiration

The team would like to thank R.D. Schuiling and Poppe De Boer, whose passion for olivine weathering and insightful research provided significant inspiration for the Project Vesta vision, and whose work in many ways continues to guide this promising field.

How It Works

8
Arctic sea ice / Re: The 2020 melting season
« on: May 18, 2020, 07:11:03 PM »
    Excerpts from:  The Largest Arctic Science Expedition in History Finds Itself on Increasingly Thin Ice.  By Michael Kodas. May 17, 2020 in Inside Climate News. https://insideclimatenews.org/news/16052020/arctic-coronavirus-climate-science-mosaic-research 
    The statements below from a great article about the MOSAiC expedition give insight to the current state of the ASI and the 2020 melt season to date.  The article appears to have been written when the May 11-15 weather was in the forecast, but had not happened yet, so the effects of that weather were not known.  The May 11-15 "clear-sky / warm-up / Fram-flush" almost certainly exacerbated the conditions described in the article.

--------------------
     " Even before the expedition had finished setting up its camps and instruments in November, the ice started cracking. Then, a storm sent huge rifts through the floe and knocked out the power system for several days. Cracks revealing open water repeatedly isolated Met City, sometimes forcing researchers to walk for more than an hour around the fissure to reach the site, a few hundred yards from the ship.

     "We just didn't know that we were going to face this much cracking," Shupe told me. "It really did take us by surprise, even though we knew the ice was thin, we knew the Arctic was different, it still snuck out ahead of us somehow." "

----------------------
     " An unusual weather pattern, which included the opening this spring of the largest ozone hole ever measured above the Arctic, produced winds that pushed MOSAiC's ice floe across the pole much faster than the expedition's organizers expected.

     "We have this kind of flow regime in the Arctic right now that's been really static," Shupe said. "It's stuck where it is and it's blowing us across the Arctic faster than anticipated, faster than any of the past 12 years that we used in our analysis to figure out where we would go." "

--------------------
     "Maybe the ice would slow down or even reverse direction, as it had early in the expedition, he thought. Colder weather might freeze some of the leads of open water that had fractured MOSAiC's floe. Maybe the ice would stabilize. But, increasingly, Shupe was having to come to terms with the fact that the ice floe he had hoped would be the expedition's home for a full year was unlikely to survive the summer.

     "I went into it ready to be surprised, and it still got out ahead of me," he told me. "How fragile the ice has been. I knew it was gonna be thin, but it's still thinner and more fragile than I thought it would be."  "


9
The politics / Re: Economic Inequality
« on: April 10, 2020, 12:13:31 AM »
David Sirota on free COVID treatment in the USA: Fear is the key

"in a political system owned by billionaires, workers are only permitted to get the absolute minimum amount of free health care that may prevent them from infecting billionaires."

"they and their families are indeed personally jeopardized by that grocery worker being unable to afford COVID testing and treatment"

"that same affluent political class opposes Medicare for All because they cant get cancer from poor people"

"the peasantry is only allowed to be given the minimal amount of free health care that makes sure the gentry don't get infected—nothing more. "

" the rich and powerful will only act out of fear, never out of a sense of moral solidarity"

https://www.commondreams.org/news/2020/04/07/top-sanders-aide-david-sirota-explains-why-billionaire-class-will-support

sidd


10
Lots of action in the past few days, clearing of fast melange, and calvings. Click to play.

11
Arctic sea ice / Re: The 2020 melting season
« on: March 29, 2020, 08:42:49 PM »
nothing out of the ordinary
One thing that is different, or that I haven't seen before, is the large leads that have developed since feb15 making their way around north greenland so early in the season. With >80km/h winds forecast on apr1 we are likely to see them open up more.
Kaleschke SIC leads, oct1-mar29

12
Walking the walk / Re: Gardening
« on: March 27, 2020, 09:17:17 PM »
Most likely "damping off". Fungal disease that suddenly kills seedlings. Google it and you'll see solutions (for next time, these ones are finsihed).

What I do is that I put the seeds into the pot, and water them in with cold chamomille tea (which is a weak fungicide), later waterings are with normal water. After planting I put some freshly ground cinnamon powder on top of the soil (also fungicide and helps plants grow faster). This way even if your soil is not sterile damping off usually does not happen.  Do not overwater.

One more trick (for melon seeds): soak them in milk for one day before planting. Also helps fend off fungal diseases.

Bonus trick for later: you can spray tomatoes, melons, grapes and even apple trees with 1:5 milk-water. This (google it, there are studies) creates good bacteria/fungi on the plants' leaves and there remains no room for the bad guys. it works

13
Consequences / Re: COVID-19
« on: March 19, 2020, 04:59:40 AM »
99% of all elderly who died from the virus in Italy (median age 80) had other serious illnesses – 50% had 3 serious conditions.
And 100% of all 50 who died aged below 40 had serious underlying conditions.
More evidence that deaths “from Coronavirus” is only to a limited extent actual incremental deaths – statistically.

"99% of Those Who Died From Virus Had Other Illness, Italy Says"
https://www.bloomberg.com/news/articles/2020-03-18/99-of-those-who-died-from-virus-had-other-illness-italy-says

Thoughts: Which means that we close down whole regions and countries, shutting borders, forcing numerous businesses into bankruptcy, and in essence now start a global recession just in order to save some sick, old people? Where is the cost benefit analysis of that?

Oh, we will all die, eventually. [/sarc]

Seriously, I think the current policies of quarantines and shut downs etc., are wrong.
I think the old and sick should be maximally protected and quarantined, but the rest of population should be let free to live their lifes.

Expect some serious discussions on this topic in the coming months, as the social costs of shut-downs will rise and rise and rise.
 

14
The forum / Re: Forum Decorum
« on: March 14, 2020, 04:14:02 PM »
Just my advice pietkuip, it is one thing to be right and one thing to be smart about it.
State your opinion clearly once (use less harsh language) and certainly don't continue back-and-forth arguing, especially if it's a one-on-one discussion. Readers here have eyes to see and brains to think and they will come to their own conclusions, have no fear. Even more importantly, don't make it personal and don't take it personal.

15
Arctic sea ice / Re: The 2019/2020 freezing season
« on: March 08, 2020, 03:45:08 PM »
Your weekly updates. Ice drift map first for a change.

CAA is remarkably static. The low winter temperatures in this area are showing.

Polarstern continues its drift towards Fram after a day with handbrakes on.

16
Most beautiful satellite glitch <3

17
Arctic sea ice / Re: The 2019/2020 freezing season
« on: January 15, 2020, 04:13:56 AM »
Hi all,

As an amateur observer, I've paid quite close attention to the Arctic this season, so maybe others can elaborate on some things i've noticed.

1) Cyclones in the North Atlantic. For the last 2-3 weeks, deep developing cyclones have been a constant. A couple have reached 940mbar, real monsters. Pulling right down the Greenland current, and undoubtedly affecting Arctic inflow with Atlantic water. Sidenote: I have to imagine these winds and 15m waves hitting Greenland, probably has some affect on underwater melting via mixing?
 
https://www.severe-weather.eu/recent-events/north-atlantic-onroll-intense-extra-tropical-cyclones-mk/

2) Incoming collapse of the Beaufort High. The typical anti-cyclonic gyre wind and pressure is getting increasingly encroached by cyclonic low-pressure. I don't know enough about this, but the research i've seen has insinuated the effect on ice formation in the Pacific ice, Beaufort/Chukchi/ESS, but can also affect the CAA.

Zack Labe actually had a picture in the melting season, that showed the significant meridional anomaly right up the Bering for the year (pic link right below). I'm guessing it was the high pressures from the Pacific contrasting with the Aleutian lows. I haven't watched enough years for precedent data, but there's also been some cyclone formation closer to the land masses on the Pacific this winter season. That can advect some real warmth.

https://pbs.twimg.com/media/EB5d4YuU4AAgalW.jpg

And just my opinion, but baroclinity and cyclone formation + the low pressure patterns they arise from (and contrasting high pressures) with baroclinity differences seem like they may be understated in the grand scheme of things. We've seen the effect in late summer, the effect it can have over the Barents, and the water flow + advection they can perform, which could serve to only exacerbate the situation. Long term, anyway.

The US has also been getting hit by severe weather, and more coming the next 5-7 days. So if you're interested in snow extent, snow depth, etc, may want to check on that the next week. There was also a minor chance of a vortex disruption, but who knows. The last few have occurred around early February for US weather, I believe.

https://www.severe-weather.eu/global-weather/15-day-outlook-ridge-cold-usa-europe-fa/

18
Arctic sea ice / Re: MOSAiC news
« on: December 29, 2019, 11:55:48 PM »
Two significant new offerings at Meereis Portal: the interactive buoy GIS display discussed earlier in #437 and release of sea ice motion radar cam scenes looking out from the Polarstern bridge  (link in #454).

Note the comparable radar on the antique RV Lance digitized an image a minute with a 360º view and range of 9 km during N-ICE2015 whereas with Mosaic the 280º field of view excludes the Ice Cam, reports every six hours (ie at 1/360 the frame rate) with only 5.2 km of range.

Note the 06:00 daily nadir S1AB coincides with the 06:00 oblique ship radar, meaning the two cannot be color-composited though the Sentinel at 200% can fill in the missing ice camp (2nd image).

We looked at marginal ice zone action and a radar cam article back in #83: https://doi.org/10.1002/2016JC012387

Presumably the PS has more sophisticated radar than they're letting out because you can buy better recreational boating radar for a few $k on ebay. The blackout on the Ice Camp could plausibly be attributed to rfi with all the other equipment out there. Dedicated instruments and strain panels monitor conditions there but that data has not been shared except anecdotally (and via S1AB analysis here). 

The full dataset is sent daily over the Polarstern's fast internet (still being denied on Dec 27th) to Bremerhaven where it is bundled into rolling windows of two weeks extent (14 days x 4x = 56 frames served as slow avi movies). The archive goes back to Nov 1st but increments daily. No explanation has been offered for the delayed upload on Dec 15th and first mention on "Follow Mosaic" on Dec 28th.

It's not clear if the Oct 4-31 floe motion is being held back or just delayed. The ice would have been in total chaos back then going by the chaos of the last two months in strengthened thickened ice, below. The minute-by-minute research grade terabyte dataset is not available which is appropriate.

The archive began duplicating the avi with identical and fully interchangeable m4v formatted videos on Dec 15th, reminiscent of the head-scratching duplication of 'mosaic_multisensor' with all-purple sea ice concentration overlays.

The file sizes are kept to a few MB using avi even though they are really just gif slide shows. ImageJ is very unusual in having an avi reader. This opens them as image stacks, with helpful options for grayscale and 180º rotation (to better align with S1AB and other 'greenland down' satellite imagery).

ImageJ is also very good at sharpening the periphery, reducing the overly bright returns from ice near the bow, changing palette, and concatenating bimonthly bites into a single image. Surprisingly converting the avi to forum-friendly mp4 at https://cloudconvert.com give as very helpful further reduction in file size.

The smaller gif at the bottom features the dramatic lead that opened a few km south of the Polarstern on 15 Dec 2019. Moderate benefit can come from contrast enhancement, sharpening and an indexed palette.

The bridge radar is confusing on first view, so set it on loop and (after download) click repeatedly on the double arrow to speed it up. The white scale bar is intrusive. Its central tip is the center of the fixed polar coordinate frame in which the bridge radar is stationary. It isn't clear if the bow-stern axis is also fixed nor if it points north-south. (The integrated navigation system records this information but it is not provided.)

The timestamp would be better with seconds and minutes rounded away, repositioned lower into vacant black space. The stern may wag about causing the view to shift when little is actually happening; the ship is also drifts and rotates quite a bit over the 60-day time frame of the video.

Overall, it is astonishing that scientists have been able to keep equipment deployed on the ice running at all. Actually, we have no idea how Leg 1 data collection went as little can be gleaned from short :) reports.

Expeditions like this were already being squeezed out of the picture by advanced calibrated satellites, massive buoy arrays and long range autonomous gliders. The ice seems too far gone for the floe platform concept to work.

Just because the ship will be drifting aimlessly until early January (when winds sweeping up from Siberia will finally send it Fram-ward) doesn't mean the ice will be quiescent. Worse, record lows have arrived with -34.7ºC recorded on 19-12-28 at 23:00 utc, making damaged equipment that much harder to repair.

And it seems that we are far short of the 8-10 extreme weather events expected in winter at the Polarstern's location (below or see #368). It's been quite stormy in the North Atlantic but so far extreme weather has not moved up past Svalbard to any extent.

19
Policy and solutions / Re: If not Capitalism... then What? And, How?
« on: December 29, 2019, 08:54:32 AM »
Matthew:13:12 KJV

"For whosoever hath, to him shall be given, and he shall have more abundance. But whosoever hath not, from him shall be taken away even that which he hath."

Brought to you by Supply Side Jesus: Rejoice !

https://imgur.com/gallery/bCqRp

sidd

20
Arctic sea ice / Re: The 2019/2020 freezing season
« on: December 20, 2019, 12:28:41 PM »
Thanks johnm33, I hadn't seen these before.

https://www.uaf.edu/cfos/research/institute-of-marine-scien/zygmunt-kowalik-publicati/Kowalik-Tides.pdf
Quote
The  largest  component  of  the  tide  in  the  Arctic  Ocean  is  the  semidiurnal  M2 (period  12.42h).  Since  the  tide  producing force for this constituent in the Arctic Ocean is very  small,  the  origin  of  this  wave  is  an  incoming  tide  from  the  Atlantic  Ocean.  The  M2  tide  entering  the  Arctic  Ocean  between  Greenland  and  Scandinavia  is  divided  by  Spitsbergen into two branches. The main wave enters through the Greenland Sea and the secondary wave propagates around Scandinavia  towards  the  White  Sea.  The  latter      has  amplitude at Northern Norway of about 1m. In the White Sea at the entrance  it grows to  about 2-3m and in the shallow Mezen Bay the amplitude is greater than 4m.   The  M2 wave  in  the  main  basin    of  the  Arctic  Ocean  propagates  during  one  period,  counterclockwise  around  an  amphidromic point located off the Canadian Archipelago. The tidal  amplitude  is  zero  at  an  amphidromic  point,  and  it  increases    towards  the  shoreline.  While  traveling  in  the Arctic Ocean the M2 wave undergoes transformation. When it impinges  on  the  North  Siberian  Shelf  its  amplitude  diminishes  through  the  bottom  friction.  Along  the  North  Siberian  Shelf  the  amplitude  is  about  20-30cm  and  further  the amplitude decreases to 5-10cm at the Alaskan shore. The M2   tidal currents in the deep basin are quite small of the order of 2cm/s. The strong currents were observed along the coasts in the shallow water of the Barents Sea, especially over  Spitsbergenbanken  and    close  to  the  Bear  Island.  The  strongest  currents  often  up  to  2m/s  occur  at  the  entrance    to  the  White  Sea.  Along  the    North  Siberian  Shelf, 
especially  in  the  region  of  the  New  Siberian  Islands,  the  M2   tide  currents  are  often  of  the  order  of  50  cm/s.  The  variability of the tidal currents is much stronger compared to  the  tidal  levels,  because  currents  depend  on  the  local  conditions, e.g., the currents along Alaska Beaufort coast are  of  the  order  of  5-10cm/s,  but  in  the  narrow  entrances  to the coastal lagoons they  can be enhanced several times. Amplitudes of the second semidiurnal constituent S2 (period 12h)  are  much  smaller  but  the  general  picture  of  the  wave  propagating  counterclockwise  in  the  main  basin  is  very  similar to the M2 wave. 
https://www.researchgate.net/figure/The-schematic-pattern-of-the-model-M-2-energy-flux-in-the-Arctic-Ocean-and-adjacent_fig5_44021887

21
Arctic sea ice / Re: MOSAiC news
« on: December 19, 2019, 05:43:16 PM »
I was wondering why the MOSAIC podcast "Arctic Drift" is in German. Now i heard Markus Rex speaking English and i'm wondering no more.




22
Arctic sea ice / Re: What's new in the Arctic ?
« on: November 15, 2019, 12:16:57 AM »
Couldn't figure out where to put this so ...

Sea Ice Movements Trace Dynamics Transforming the New Arctic
https://phys.org/news/2019-11-floe-sea-ice-movements-dynamics.html

Research led by the University of California, Riverside, is the first to use moderate resolution imaging spectroradiometer, or MODIS, satellite imagery to understand long-term ocean movements from sea ice dynamics. (... I think A-Team might beg to differ)

... "No one had bothered before to use MODIS because the satellite is sensitive to clouds and it's hard to identify ice," Martinez said. "Our algorithm automatically filters clouds and uses other image processing algorithms that give the velocity and trajectory of the ice floes."

"MODIS data is one of the longest records of earth ever compiled," said first author Rosalinda Lopez, a graduate student in Martinez's lab. "This means that we are able to expand our analysis to almost two decades to observe the variability of sea ice as dramatic changes transform the region."



R.Lopez-Acosta, et.al. Ice Floe Tracker: An algorithm to automatically retrieve Lagrangian trajectories via feature matching from moderate-resolution visual imagery, Remote Sensing of Environment (2019)

Abstract:

Satellite observations of sea ice along marginal ice zones suggest a strong coupling between sea ice transport and the underlying ocean turbulent eddy field. Moderate Resolution Imaging Spectroradiometer (MODIS) satellite imagery spanning over almost two decades of daily observations at a resolution of up to 250  m provides a good resource for deriving long-term ocean kinematics from sea ice dynamics.

In this paper, we present a newly developed automatic algorithm to retrieve dynamic measurements of sea ice from these images. We describe the methodology by presenting results acquired along the East Greenland Current (ECG) for 6.5  weeks in the spring of 2017. During this period, our ice floe tracker was used to identify and track ice floes with length scales ranging from 8 to 65  km. By effectively filtering atmospheric conditions from MODIS images, ice floes were tracked for up to ten consecutive days, and a total of 1061 trajectories were retrieved.

 A southward mean sea ice flow associated with the ECG was observed along with deviations in both direction and magnitude, suggesting the effect of an underlying turbulent eddy field. The absolute position and tracking errors associated with our method are 255  m and 0.65  cm/s, respectively, each derived from a comparison between manually and automatically identified ice floes. Going forward, our methodology will be employed to process longer time sequences to analyze nonlinear interactions between drifting ice floes and the upper ocean turbulent eddy field in the ECG as well as to investigate other prominent regions of the Arctic Ocean.

23
Arctic sea ice / Re: The 2019/2020 freezing season
« on: November 12, 2019, 10:48:00 PM »
The Chuckchi sea (and the Bering) can really start the next melt season with the record low volume (again). But it won't be a catastrophe because the CAB still have the pretty thick ice that will mostly survive the melt season.
This is wrong. The Chukchi and Bering are, IMO, directly tied to the freezing season in North America and its duration. If the Chukchi and Bering's volume remains at record lows through the freezing season and into the spring, there is a very good chance winter will not abate until May, or even June, across the most productive food-growing regions on the planet.

We already have a catastrophe unfolding after this year's late start and early finish. If 2020 repeats the same pattern (or worse) there will be major shocks to food prices beyond what is already likely in the pipeline due to this year's harvest.

If the CAB has ice when people start to starve, BOE will be trivial at that point. The impacts are already well underway due to certain regions becoming increasingly ice-free, and we may not even need an ice-free CAB to see catastrophe unfold in the form of spiraling food prices.

24
Permafrost / Re: Northern Hemisphere Winter 2019-2020 Snowcover / Misc Obs
« on: November 12, 2019, 10:37:35 AM »
  an early freeze would reduce snowfall in the vicinity by killing lake effect snow .. b.c.
It doesn't eliminate LES, strong winds move ice around and re-open the Lakes until at least Feb / Mar, and even with full 100% coverage this will still happen. It does cut down on LES.

But with the Chukchi now open in all of November and Bering the same for DJF, there is probably enough offset from up north for the difference to be less relevant than it would be otherwise (and this is the primary reason for the supremely FRIGID temps of late, as the +precip / +snowfall in areas that are close to desert is enough to drop their temps dramatically, which translates downwind). This is specifically in reference to the elevated "Triangle of Coldness" between the Northern Rockies, Hudson Bay, and the GL.

By springtime, as the ice begins to melt, I think the flux and extant ice are very much supportive of much more snowfall as a percent of overall precip when the lakes are covered (at least in their vicinity +/- a few hundred miles).

25
Arctic sea ice / Re: Arctic Ocean salinity, temperature and waves
« on: September 22, 2019, 11:53:23 PM »
if anyone has suggestions for a better calculated value to display, let me know please.
Very nice. As the data is quite old it may be more interesting to animate depthwise, rather than date. Perhaps a 10m average down to, say, 350m? If you are prepared to share code it would be most welcome on a dev thread.
This approach may also work well with the mosaic buoys.
L3 data time series would be handy for comparison with more recent data in similar locations though. Can you provide a link pls?
edit: I read the small print and see data goes up to 2019

Thanks, your suggestion turned out nice and I want to go deeper but ran out of time, so 0-350m it is for now. I'll post the R code over at the dev thread with some warning of amateur practices. Only for the final.zip data again, the others have different structures but next on the list.


26
Arctic sea ice / Re: Arctic Ocean salinity, temperature and waves
« on: September 20, 2019, 11:55:48 PM »
Great news :)
Reposting  whoi itp110 7m-50m from 2018, day264 to 2019, day120 (at location -134.8350  73.6623N) with location insert.

edit: corrected label and added part2
whoi itp110 7m-80m from 2019, day123-218
density green, temperature purple, salinity red
temp    -1.8 to 0.6C
salinity  27.5 to 31.2
density 1021.5 to 1025kg/m^3

27
The forum / Re: GIF size, your Internet, and what is usable?
« on: September 09, 2019, 11:19:44 AM »
Please, everyone doing GIFs:

In general, produce GIFs. They would work on any platform. If it's a big file (>2.5mb), canvas size should be >700 pixels so that it doesn't autoplay.

If there is no way around mp4 for you, consider uploading to Youtube and link it.

If you don't like Youtube for some reason, at least make it >700px big so they wouldn't autoplay and eat up data budget for users.

Thank you. :)

Pro-tip concerning screenshots. Even screenshots can be very big in file size. Upload them to EZgif, adjust canvas size to 700px, optimize it at 35 and then download as a GIF. You can easily make a 2.5mb file to be 150kb. Better for the forum server, the users and the CO2 consumption. Everyone is happy.  ;D

28
Arctic sea ice / Re: The 2019 melting season
« on: September 01, 2019, 08:23:54 AM »
August 27-31.

2018.

Additionally: August 1-31 (fast).

29
Arctic sea ice / Re: The 2019 melting season
« on: August 30, 2019, 10:47:39 PM »
The latest five day forecast looks like a disaster for the ice if we were still in the melting season... But this is my first crossover into the freezing season, so I have no idea what this mess will do to the ice. It sure looks bad!

I hope you Like it! It's Free! ;)

30
Arctic sea ice / Re: The 2019 melting season
« on: August 30, 2019, 12:29:27 AM »
Mercator 0m sea temperature with unihamburg amsr2-uhh overlay at 60% transparency. amsr2 0% concentration (open water, normally dark blue) has been set to fully transparent to show sst, mar21-aug28. (best viewed full screen, double click or right click) Note the amsr2 concentration wil be affected by the overlay and should only be seen as a guide.
Processed satellite data overlaid onto model data is somewhat questionable but the images dovetail pretty well at the ice edge. (model details here https://www.mercator-ocean.fr/wp-content/uploads/2017/02/SYSTEM-sheet-_PSY4V3R1_2017.pdf)
I don't know if the jet from the Ob river to the LaptevCAB exists but it aligns with the bathymetry and the surface ice drift.
The west spitzbergen current has struggled more this year against fram export.
CAA/CAB crack will probably continue to be low concentration ice for a while even if the winds turn northerly.
Southern end of the Beaufort arm is likely to succumb to the warmer waters of the Amundsen Gulf.
Low concentration CAB areas - Who knows? Sterks mentioned something about particle size and fluids before leaving. 'It's sea ice Jim, but not as we know it' ;)


31
The forum / Re: Forum Decorum
« on: August 13, 2019, 11:03:06 AM »
My interpretation:
Sterks shouldn't have posted his personal fight with Neven here for all to see. I think that's disrespectful and unconsidering (We know Neven is in a difficult and stressful period because of family reasons).
Yes, Sterks had good contributions so that's too bad.
Warning: stay away from political discussions!  ;D ::)

I agree.

I don't touch any threads outside this one, the forum humour thread, and the Cryosphere sub-forum. From what I've seen of sterks & teapotty is their off-colour crud is quite similar. You know what? You shouldn't engage in such childish crap. Don't acknowledge it at all; simply report it & move along. They will be the one getting the boot, in time. That's the smart & more civil way to handle it. Don't let them drag you down to their level. Seems that's what happened here.

Personally, I post like my mom might be reading. Not like how I drive.  8)

32
The forum / Re: Forum Decorum
« on: August 12, 2019, 01:18:09 AM »
pot · kettle · black

I'd ban all kitchenware from the Cryosphere sub-forum, at this point. Or just scrap the forum entirely & stick to the blog only. Seems our primal instinct of throwing feces at each other from our respective branches is far from behind us yet. All we've done is name the behaviour [ego] & make excuses for it. So sad to see it propagating on such an objective/science-oriented board such as this.

 :-\

33
Arctic sea ice / Re: The 2019 melting season
« on: August 10, 2019, 04:12:56 PM »
July 13 - Aug 9 (4 weeks)

This animation is a 5-day minimum, not median.

Using the minimum introduces some artifacts. Areas of low concentration ice that are moving will leave a 5-day memory on every pixel they cross; for example, areas of part water and part moving ice, such as the Beaufort edges or ESS, will look like they have more open water than they really do. Similarly, if there are low concentration cloud artifacts, they will also be preserved for 5 days. Also, if new ice were forming, it would likewise not show up for 5 days; but no new ice is forming yet.

However, in my experience, the vast majority of artifacts in these maps are high concentration cloud artifacts, and using the minimum does well at removing most of those. If you follow the evolution of the ice edge this seems to do a good job and maybe hints at what might be coming, such as a continued edge retreat in the Beaufort (minus advection) and NW of the Laptev bite.

Maybe think of this map as something like a worst-case scenario. Use the originals (on the right) as a guide to aid interpretation.

Large file - click.

34
Arctic sea ice / Re: The 2019 melting season
« on: August 08, 2019, 10:16:22 PM »
Quote
'cold air has been flowing persistently to northern Finland from the Arctic ocean'
and doing its best to take the ice with it. Not that it gets far into atlantic waters.

Today looking at mercator 0m sea temperature with unihamburg amsr2-uhh overlay at 60% transparency this time to allow some of the mercator model's higher coastal SST's beneath the ice to show through. I didn't notice that before doing this overlay. That would explain the rapid melt of ESS/Laptev fast ice. amsr2 0% concentration (open water) has been set to fully transparent, jun1-aug7.
Attention is unsurprisingly mostly on the Chukchi/Beaufort and Laptev at the moment but note also the heat building up to the east of the Fram Strait.
The CAB beginning to resemble a ripe stilton

35
Arctic sea ice / Re: The 2019 melting season
« on: August 07, 2019, 10:21:13 PM »
Looking at the Parry channel there would seem to be a connection between ice break up over the shallowest part, south of Resolute, and ice break up at the mouth of the Mclure Strait. That probably doesn't surprise anyone, but it also looks like, this year, there may be a connection to sudden melt over beaufort deep water west of Mclure Strait. One possible reason is that a larger volume of water has been drawn into the Mclure Strait, causing upwelling close to the shelf further west. Or it could just be coincidence.
whoi itp103 passed by the Mclure Strait recently and the microcats detected a significant temperature spike, but no increase in salinity, perhaps due to meltwater from above.
itp103 location on day560    -129.8953  76.6136, west of Mclure Strait

gmrt bathymetry with unihamburg amsr2-uhh overlay at 75% transparent. Open water, normally dark blue, set to fully transparent, parry channel area, jul1-aug6.
gmrt bathy for reference
whoi itp103 microcats, mounted at 6m and 7m depth
whoi itp103 drift track

edit: unfortunately no scale with my favourite bathymetry map but point and click depths are available at their veiwer here https://www.gmrt.org/GMRTMapTool/np/  blue is deep, beige/grey is shallow. Heavy contrast here to bring out the contours.

36
Greenland and Arctic Circle / Re: The Nares Strait thread
« on: July 27, 2019, 08:56:52 PM »
Stiff winds blowing down the Strait.

37
Arctic sea ice / Re: The 2019 melting season
« on: July 27, 2019, 03:10:39 PM »
Bearing in mind some of the comments on the ice thickness products upthread, here is ascat overlayed with unihamburg amsr2-uhh at 55% transparency. To allow the ascat features to show through, amsr2 100% concentration ice, normally white, has also been set to fully transparent.
Although weather/other interference obscure many ascat features recently, I think the animation still gives a rough guide to the position of the older and possibly still thicker/more resilient ice that remains.
mar21-jul26.
ffmpeg -crf 27 switch to reduce file size. Where ascat data is missing or poor quality the nearest days have been duplicated, causing some stutter

38
Arctic background / Re: Arctic Maps
« on: July 22, 2019, 09:07:57 PM »
Thanks again everyone.
johnm33, I occasionally get incomplete contours, so I suppose I will try again, although if I zoom in that far it will be tricky to patch all the images together.
mitch, I've seen the letter sized map, I was hoping for something larger. Though it is pretty good when zoomed using acrobat. I'll try patching that together too.

I tried heavy contrast on the previous compilation and surprise, the contours are there. They are nearly all the same colour though. Here is the heavy contrast version, which satisfies me for now.

39
Arctic sea ice / Re: The 2019 melting season
« on: July 22, 2019, 01:19:53 PM »
Perhaps more of a worry is that the low concentration area is at the tip of the atlantic current, here shown using mercator salinity at 34m. Note also the lower concentration area above the current further west.
edit: forgot scale

40
Arctic sea ice / Re: The 2019 melting season
« on: July 20, 2019, 07:58:48 PM »
After testing yesterday here is large version of unihamburg amsr2-uhh, jun1-jul19.
mercator(model) SST inset, also jun1-jul19.
Best viewed full screen.   edit:click on the square arrows icon bottom right.thanks Niall

41
Arctic sea ice / Re: Arctic Ocean salinity, temperature and waves
« on: July 06, 2019, 05:42:58 PM »
mercator(model) 0m salinity with uni-hamburg amsr2-uhh overlaid at 40%. Open water(blue) set to transparent. mar21-jul4.
glitch at the end is due to 4 mercator forecast days instead of analysis, will fix that for next time

42
Policy and solutions / Re: Space colonization
« on: July 05, 2019, 10:28:09 PM »
After carefully studying the documentary "Earth Girls are Easy" I'ved determined that the scientific breakthrough that will most benefit mankind is the ability to shrink humans.


Once properly sized the problems of sending brave, but tiny humans to Mars colonies shrinks to a manageable size.


Envision a colony capable of housing a million souls that weighs but a few kilograms and fits easily in a size 9 shoebox!


We could start by simply cross breeding Pygmy tribes with members of the Little People of America organization - but this is too slow a process, wouldn't result in the needed size reduction and might retain undesirable traits such as the squeaky voices so prominently featured in films such as the original version of the Wizard of Oz.


CRISPER technology is where we should be looking.


Once we've reduced humans to the size of small kittens we may find that we've genetically engineered our way out of the food, water and housing crises that we're soon to face.


McMansions with 10 square feet of living space will require little heating or cooling. Electric trains and EVs will run off a few "C" cell batteries, and a thin goat could provide sustenance for hundreds.
Christ's feeding the masses a few loafs and fishes will seem wasteful.


Robots will take over all the jobs requiring strength. Our sciences will continue to develop better and smaller micro-technology and micro men. Our problems will shrink away until we will no longer dream of leaving our so recently relatively enlarged home planet.


Are we men, or are we mice. Squeak up boys.
Terry

43
The 2019 sea ice area and extent data thread would be a whole lot better if the meaningless chatter was here instead of there.

44
Arctic sea ice / Re: The 2019 melting season
« on: June 15, 2019, 12:49:33 AM »
unihamburg amsr2uhh overlaid onto ascat with 100% ice (normally white) set to transparent. The amsr2 overlay is 70% transparent to allow other features of ascat to show through, notably greenland. It also helps to make the 'weather' over open water less distracting.
Similar to last year the wash of warm weather has revealed fractures in the older ice that were not visible previously.
jun1-13
thanks to A-Team for helpful hints, some of which need further work
https://forum.arctic-sea-ice.net/index.php/topic,2558.msg205561.html#msg205561


45
Greenland and Arctic Circle / Re: The Nares Strait thread
« on: June 02, 2019, 06:42:16 PM »
This rather big floe that just entered the Nares Strait has melt ponds.

(GIF requires a click to play)

46
Arctic sea ice / Re: What's new in the Arctic ?
« on: May 31, 2019, 12:33:55 AM »
I made a quick and lightweight sea ice comparison page for the entire NSIDC data set. At the moment it's just for the 1st of the month, but soon I add the 15th of the month as well.

https://cryospherecomputing.tk/PastSIC

47
Arctic sea ice / Re: Arctic Ocean salinity, temperature and waves
« on: May 26, 2019, 12:26:28 AM »
for reference, a rough overlay of global hycom cice ice thickness (GLBb 0.08-93.0) over ascat at 42% transparency.

48
Greenland and Arctic Circle / Re: The 'Very Big Chunk' poll
« on: May 11, 2019, 08:00:17 PM »
This method does appear to show tidal movement.

Yupp, see GIF. Click it!
Funny how the wave coming from the south (or something) is causing gyres in the strait right now. Have never seen it that pronounced.

Quote
By the way, does this rule out 'not!' or does it have to stay put for 24hrs ?

Has to stay put for at least 24h. Otherwise, it's 1-3 Days.

49
Arctic sea ice / Re: The 2019 melting season
« on: April 27, 2019, 07:47:45 AM »
00z Good-for-sh*t has 576DM ridging over Beaufort @ hr 120 :o

Thanks for your updates on this Bbr. One question though. Could you provide a little more commentary in plain language, so non-meteorologist can understand you too?

50
Arctic sea ice / Re: The Rammb Slider Thread
« on: April 19, 2019, 10:54:58 PM »
Looking for something about Amundsen Gulf tides found this journal from 1986.

International Hydrographie  Review,  Monaco,  LXIII (2),  July  1986CANADIAN  ARCTIC  TIDE  MEASUREMENTTECHNIQUES  AND  RESULTSby  B.J.  TAIT,  S.T.  GRANT,  D.  St.-JACQUES  and  F.  STEPHENSON (*)
https://journals.lib.unb.ca/index.php/ihr/article/viewFile/23426/27201

Quote
The  tide  in  the  southern  Beaufort  Sea  and  in  Amundsen  Gulf  propagates counterclockwise  about  an  amphidromic  point  situated near the  southwest  corner of  Banks  I.  It  propagates  quickly  along  the  coast  from  Alaska  to  a  point approximately midway along the Tuktoyaktuk Peninsula where it slows significantly,  reaching  Sachs  Harbour (site  4,  Figure  2)  on  Banks  I. about  six  hours  later.  In Amundsen  Gulf the  tide  travels  east  into  Dolphin  and  Union  Strait  and  Prince Albert  Sound  and  northwest  into  Prince  of Wales  Strait.The  tidal  propagation  patterns  in  the  waterways  between  the  eastern  end  of Amundsen Gulf and the southern end of M’Clintock Channel are complex and not yet  well  defined.  Further field  surveys  are  planned  for these  areas.

First image is fig2 from the journal.
Original rammb animation 35MB (80 frames) when cropped was 5MB and very small. Enlarged 2x took it to 18MB. Converting to mp4 gets 384kB. (click to play)
ffmpeg -i rb2.gif -pix_fmt yuv420p -vf "scale=trunc(iw/2)*2:trunc(ih/2)*2" rb2.mp4
Worldview terra modis apr18 (or nearest) 2010-2019posted on melting season (deleted here to help save the planet)

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