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Messages - gerontocrat

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The forum / Re: Arctic Sea Ice Forum Humor
« on: December 29, 2020, 02:23:18 PM »
I just did some skimming through the Consequences sub-forum. (I tend to stick exclusively to the Cryosphere bit, & here) I found some humour there, albeit not in the normal form I see posted in this thread.

I find many people posting there who simultaneously embrace science while rejecting technology. I found myself giggling quite a few times.

But I'm weird, so IDK.

I think you're confusing the notions of technological advances with technical progress. Don't forget that science without conscience is only the ruin of the soul (and eventually of the planet).
I give you a clue: a savage armed with a club or a savage armed with an AR15, technological advance or technological progress?

Arctic sea ice / Re: MOSAiC news
« on: December 01, 2020, 03:01:53 PM »
Lobelia has added flexible gif and mp4 time series generation downloads to the CMEMS ocean page linked to by a 'social media' icon next to 'add layers' that also allows iframe embedding (not supported here), tinyUrls and static pngs.

Uniq has already posted excellent examples on the main and test forums. Lobelia-CMEMS is a very important new resource for the Arctic Ocean but over the last six weeks only 2-3 of the 1795 site registrants have used it. As is said about the lottery, you can't win if you don't play.

Below, grayscale palette gif output from Lobelia has been run through ImageJ, Gimp and CloudConvert to add some graphic refinements, notably for freedom to change palette to an arbitrary LUT, move the date to a better place, recolor ocean blue, crop, rotate to Greenland down, overlay the Polarstern drift path and so on.

The mp4 shows 84 days of ice thickness as modeled by nextSim from Sept 15th out to a predicted Dec 7th. The scale has been set to range over 0-3m which has the effect of not displaying thinner ice optimally; that would require a scale setting of 0-0.5m which would not display the main ice pack at all.

It's not completely clear what the 'floes' and 'leads' actually represent down on the ice as these features are below the resolution of any of the satellite tools used by nextSim. Whatever, they do seem to allow an accurate depiction of ice movement, notably the pick-up in Fram export in mid-November.

The second mp4 shows the full range of 111 weeks contained in the archive. It is a little jumpy but the daily scale would make for quite a large file and the hourly would be way out of bounds.

The third mp4 shows ice thickness for the full year of the Mosaic expedition restricted to the Svalbard area to emphasize the vigorous TransPolar Drift and Fram export compared to the virtual lack so far this season. The file size is still quite small meaning 2x the dimensions would be about 8 MB.

These mp4 were initially made as gifs where resolution is better (because mp4 involves lossy compression). After loading and study of most effective frame rate in ImageJ, 'hourly' can easily be changed to 'six hourly' or daily' can  to 'every other day' etc. This avoids choice limitations in the Lobelia panel. However, ordering more frames slows down product delivery which is a lot slower now than Nasa's WorldView.

"The Arctic Sea Ice Analysis and Forecast system uses the neXtSIM stand-alone sea ice model running the Maxwell-Elasto-Brittle sea ice rheology on an adaptive triangular mesh of 10 km average cell length. The model is available back to 01 Nov 2018

neXtSIM uses surface atmosphere forcings from the ECMWF (European Centre for Medium-Range Weather Forecasts) and ocean forcings from TOPAZ4, the ARC MFC PHY NRT system (002_001a). neXtSIM runs daily, assimilating OSI-SAF sea ice concentrations (both SSMI and AMSR2) from the SI TAC and providing 7-day forecasts.

The output variables are the ice concentrations, ice thickness, ice drift velocity and snow depths, provided at hourly frequency. The adaptive Lagrangian mesh is interpolated for convenience on a 3 km resolution regular grid in a Polar Stereographic projection. The projection is identical to other ARC MFC products."

A Maxwell elasto-brittle rheology for sea ice modelling
V Dansereau et al 01 Jul 2016 free full text Maxwell 1867 key feature of viscoelastic model

A new rheological model is developed that builds on an elasto-brittle (EB) framework used for sea ice and rock mechanics, with the intent of representing both the small elastic deformations associated with fracturing processes and the larger deformations occurring along the faults/leads once the material is highly damaged and fragmented. A viscous-like relaxation term is added to the linear-elastic constitutive law together with an effective viscosity that evolves according to the local level of damage of the material, like its elastic modulus.

The coupling between the level of damage and both mechanical parameters is such that within an undamaged ice cover the viscosity is infinitely large and deformations are strictly elastic, while along highly damaged zones the elastic modulus vanishes and most of the stress is dissipated through permanent deformations. A healing mechanism is also introduced, counterbalancing the effects of damaging over large timescales.

In this new model, named Maxwell-EB after the Maxwell rheology, the irreversible and reversible deformations are solved for simultaneously; hence drift velocities are defined naturally. First idealized simulations without advection show that the model reproduces the main characteristics of sea ice mechanics and deformation: strain localization, anisotropy, intermittency and associated scaling laws.

The availability of ice buoy and satellite data has allowed three all-important characteristics of the deformation of sea ice to be revealed: its strong localization in space (heterogeneity), its localization in time (intermittency) and its anisotropy.

The anisotropic nature of sea ice deformation is made evident by the analysis of satellite-imagery derived ice motion products which shows that high strain rates concentrate along oriented, linear-like faults, or leads, often termed “linear kinematic features” (Kwok, 2001). The signature of the strong heterogeneity and intermittency of sea ice deformation is the emergence of spatial and temporal scalings in the deformation fields over a wide range of scales.

The rest / Re: What is your likeability?
« on: November 05, 2020, 06:49:42 AM »
worth  a reply i guess.
I have a high like ratio on this blog.
About .5
In the real world my views are  marginalized and I find it hard to relate to the "normal" person I encounter.
First and foremost I have what they call Asperger syndrome this simply means  I dont think like "normal" person. I/100 ...
2nd is IQ apparently mine is something like 2 sd to the right . another 1/100....
On this forum both of my differences are approaching normal hence what I have to say often resonates  with  the average person on here.
What does  my high like ratio mean to me ?
It makes me feel I am among my peers and a valued contributor with views worth considering rather than feeling alone in an incomprehensible uncomprehending world .

Arctic sea ice / Re: The 2020/2021 freezing season
« on: October 18, 2020, 10:12:02 AM »
There's a reason scientists studying climate change use complex models not tea cups
Worst freeze season ever underway ...
Concur.  As I observed in the extent and area thread, the numbers on the eastern side of the basin - Kara, Barents, ESS and Laptev - are terrifying.

As FooW observes, this is already having an impact on northern hemisphere circulation and weather.

While the Beaufort and Chukchi numbers are not at record breaking levels, they are not good, and the sea surface temperatures are very much so.

Looking back at another question up thread about the influence of this all... you touch on it by way of stating the heat to melt the ice year round is already present in the Arctic, it just isn't accessible... the net enthalpy in the Arctic is rising almost exponentially, and combined with the observed destruction of the haloclines in the Atlantic side of the Arctic is a dire portent for the very near future. 

The buffers which used to keep a lid on that heat are gone.  Lack of ice growth will merely be a symptom.  The real story will play out in the changes we are going to see in winter weather in the northern hemisphere.

What happens with the weather next spring will be definitive in ways humanity has not experienced in over 10,000 years.  There is simply too much heat loose in the northern hemisphere.

The analogy I think of is one which actually came from my study of geology/vulcanology.  It ties back to the observation of events prior to a phreatic explosion at the rim of a atoll volcano.  Prior to the explosion, there were major jets of steam venting from the area which would later explode.  Someone asked if that would be sufficient for the energy to dissipate.  The point made then was that the steam jets were akin to a giant sticking his finger through the hole in the roof of a hut.  There was no way the giant was going to climb through it, nor would the roof of the hut be enough to contain him.

So it is with the increase in enthalpy in the Arctic.  What we are seeing now in fact is the culmination of years of build up and Atlantification, probably starting before 2012, probably before 2007. 

The last few years, we've watched the giant sticking his finger through a hole in the roof.  I think we are about to see him emerge.

Consequences / Re: Ocean Temps
« on: September 25, 2020, 06:48:18 PM »
Major Wind-Driven Ocean Currents Are Shifting Toward the Poles

"Satellite observational sea surface temperature anomaly during the last five years (2015-2019), reference to the first five years (1982-1986)". Credit: Alfred-Wegener-Institut/Gerrit Lohmann

The severe droughts in the USA and Australia are the first sign that the tropics, and their warm temperatures, are apparently expanding in the wake of climate change. But until now, scientists have been unable to conclusively explain the reasons for this, because they were mostly focusing on atmospheric processes. Now, experts at the AWI have solved the puzzle: the alarming expansion of the tropics is not caused by processes in the atmosphere, but quite simply by warming subtropical ocean.

To date, experts assumed that processes in the atmosphere played a major role—for instance a change in the ozone concentration or the aerosols. It was also thought possible that the natural climate fluctuations that occur every few decades were responsible for the expansion of the tropics. For many years researchers had been looking in the wrong place, so to speak.

"Our simulations show that an enhanced warming over the subtropical ocean in both the Northern and Southern Hemispheres are the main drivers," says Hu Yang, the study's lead author. These subtropical warming patterns are generated by the dynamic of subtropical ocean gyres, measuring several hundreds of kilometers in diameter, which rotate slowly. These currents are especially well-known in the Pacific, because the majority of floating marine litter is concentrated in them. "Because the currents in the region bring together the surface warming water masses particularly intensely, it's easier for the subtropical ocean surface to accumulate warmth than in other regions—and the same applies to plastic," says Lohmann. As a result of this warming of the subtropical ocean, the tropical warm ocean regions are expanding. According to his calculations, this phenomenon is the catalyst for the tropics expanding to the north and south. "Previous researchers had been taking an overly complicated approach to the problem, and assumed it was due to complex changes in the atmosphere. In reality, it's due to a relatively simple mechanism involving ocean currents."

What led the experts to explore this avenue: data on ocean gyres that they happened to come across five years ago—data on ocean temperatures and satellite-based data, freely available on databases. Both sources indicated that the gyres were becoming warmer and more powerful. "That's what led us to believe that they might be a decisive factor in the expansion of the tropics," explains Hu Yang.

The AWI experts were right: their findings perfectly correspond to actual observations and the latest field data on tropical expansion. Just like in reality, their climate model shows that the tropics are now stretching farther to the north and south alike. In the Southern Hemisphere, the effect is even more pronounced, because the ocean takes up more of the overall area there than in the Northern Hemisphere.

Hu Yang et al, Tropical Expansion Driven by Poleward Advancing Midlatitude Meridional Temperature Gradients, Journal of Geophysical Research: Atmospheres (2020)

Arctic sea ice / Re: The 2020 melting season
« on: August 23, 2020, 12:51:28 PM »
Updated version (improved colour scheme) of the comparison between the extent and concentration changes for the first 3 weeks of August.

Greenland and Arctic Circle / Re: The Nares Strait thread
« on: June 26, 2020, 11:38:46 PM »
2 day gif of Kennedy and Kane Basin.  (needs a click to run)

One example of billions of that.... When the cod fisheries were collapsing on the great bank, then President Reagan responded by supporting the fishermen buying and building bigger and better boats with better equipment to catch more fish to maintain their lifestyle and their catch. That of course accelerated the destruction of the ecosystem and the evolutionary response to fish becomming smaller than the nets could catch, and smaller than were economically viable. This only stopped when there were simply no more fish to catch. At no point were those in charge or involved able or willing to recognize the right answer. They had to not just dramatically reduce the catch to allow the stocks to recover, they had to stop fishing for them entirely. Instead they chose precisely the opposite action and destroyed the ecosystem, and with it any potential of returning to "normal" in anyones lifetime.


As an engineer I concur with your various assessments, and I note that not only does your example of conservative President Reagan counterproductive efforts to help cod fisherman work to accelerate the degradation of the environment, but the linked article discusses how left-wing efforts to implement green technology can also work to create a rebound effect that encourages the general public to consume more goods and thus to work to further degrade various Earth Systems:

Title: "Green technology will not save us"

Extract: "The UN also warns that using green technology may be less beneficial (and in some cases, more harmful) than expected. It’s called the rebound effect - instances where technologically-driven advances in energy efficiency increase, rather than decrease, consumption leading to net-zero (or worse) emissions. For example, because electric cars cost less to run, consumers may drive them further and more often which wipes out the eco-advantage these vehicles have over their gasoline-powered counterparts. According to the Breakthrough Institute, a research centre that promotes tech solutions for environmental and human challenges, this effect means that “for every two steps forward we take in energy savings through efficiency, rebound effects take us one (and sometimes more) steps backwards.” This may erode up to 50 per cent of the eco-benefits promised by green technology by 2030, according to a paper by Barker, Dagoumas and Rubin."



I can go you one better - closer - in terms of impacts on climate change. The Powers that be (TPTB) decided that electricity use for lighting was low hanging fruit that they could attack to reduce energy consumption in the battle against climate change. New lighting was developed with a discovery in Japan that allowed for the energetically efficient production of blue light using photodiodes. This discovery was combined with phosphors (mostly pure orange) place on top of the diodes to absorb some of the blue and remit it as orange to produce a light that appears to humans to be sort of white. Depending on the mix of blue and orange the light is either harshly blue, or orangish (warm).

The technology advanced and the devices went into mass production. Governments around the world then mandated that these highly energy efficient lights be used and that "wasteful" incandescent lights be banned. The US passed this in the 2007 Energy and Infrastructure act.

Unfortunately no one seems to have thought this through. The safety standards for the lights are based off of retinal heating lessons involving lasers and bright light sources, with some minor recognition of the blue light hazard. In the case of LED lights they chose to set a "safe" standard of 1,000,000 watt-seconds/square meter/steradian. They then set a series of groups RG0, RG1, RG2 that allowed different illuminance values (100 watts/square meter/steradian for RG0) and allowed exposure times per day (10,000 seconds for RG0). The thinking was I suspect that 10,000 is a big number and 100 is sufficiently bright, that that seems a good combination to define as "exempt".

10,000 seconds is 2 hours and 47 minutes. After that period of exposure, no additional exposure is safe for the rest of the day.The body needs time to recover from the photobleaching of the retina.  Almost all of the lights being sold commercially are of this type. One manufacturer, SORAA, has lights that are somewhat different. They are based on producing violet light and using a broader range of colored phosphors.

A number of factors were not considered.

1) How people actually use light. (more than 10,000 seconds a day, and computer and device use adds to the exposure).
2) That once this level of exposure is exceeded that retinal injury IS occurring - and that that leads to insidious progressive blindness as the blue light bleaches the retina and triggers the body to order cells showing excessive damage to commit suicide.
3) That blue light also impacts the intrinsic photosensitive retinal ganglion cells (ipRGC) which control the circadian rhythm response
4) That the conversion of AC power to DC with inexpensive circuitry results in light that oscillates at twice the power frequency (100 or 120 hz in most of the world), AND shifts back and forth from intensely blue to intensely orange as the diodes drive the phosphors out of phase with themselves. This results in all manner of eye stress, guaranteed inability to focus as the eye tries to focus at two different focal lengths, and loud tinnitus, optical migraines and migraines as the brain sees motion everywhere in the visual field and activates the default mode network warning of danger.
5) That the LED lights do not have the throw of the lights they replaced, necessitating twice as many street lights
6) That the disruption of the circadian rhythm would inevitably lead to increase rates of hormone sensitive cancers, heart disease, obesity, type 2 diabetes, depression, suicide, behavior disorders, performance disorders, etc...
7) That advertisers would quickly realize that they could use this technology to light entire sides of buildings in full color displays, thereby increasing light pollution, circadian rhythm disruption and light pollution.
8 ) That the increase in blue light would destroy the night sky and astronomy
9) That animals, plants and insects would respond adversely to such light at night (e.g. salmon will not migrate upstream at night under bridges using LED light; that bird migration is disrupted, that insects are highly disrupted)
10) That people vary in the way they see and respond to light, with some being highly sensitive, and some much less so, that they have strong differences in color and light level response, that these change with age (young and old are especially vulnerable), or that some people are distinctly different in having eye diseases (AMD) or immune system disorders that are strongly impacted by intense blue light
11) That green light (which these lights generally do not produce) is incredibly important in reducing pain, and thereby offsetting opiate needs
12) That red light is essential in driving mitochondrial function through skin and tissue exposure to red light
10) and on and on and on

Lets look at just two of these aspects.

1) The sleep disrupting effects of blue light impacting the ipRGCs is well documented. The most recent study from Barcelona, Spain last year documented an actual observed 47% increase in the rate of breast cancers and a 105% increase in the rate of prostate cancers from the introduction of LED streetlights alone. Indoor use in the home of LED lighting further increased these rates by 50%.

Applied to the United States for example the first 15 years use of LED lighting (the expected life of the lights), should result in an increase of 20 million cancers and 4-5 million cancer fatalities. At some point attorneys will likely realize that their clients and their families can and should assert that the light injured them through the sleep impacts. Because the increase is so large (105% for prostate cancers), that it is more likely than not that the cancers were -caused- by the lights, making the lighting manufacturers potentially liable for ALL prostate cancers. I am not a lawyer, and this is for the courts to decide. But that seems all too obvious and preventable. For people with macular degeneration, no exposure is acceptable. They are effectively denied their rights to free travel and free association. They are injured everywhere these lights are used.

2) The flicker of the lights is causing differential impact to a small fraction of the population. For them the impact is extreme. They can no longer safely leave their homes at night, shop in stores, or participate in public functions or government. And they cannot safely work. The tinnitus, migraines and optical migraines essentially end their productive lives.

What should be clear is that the solution is to eliminate blue from all light use at night. because of the impact to sensitive people (infants, the elderly, those with AMD ...) that likely means essentially eliminating blue light from all lighting.

Interestingly, the increase in prostate and breast cancers occurred after fluorescent lighting entered the scene. It is conceptually possible that a large fraction of the base rate of these cancers may have been caused by the blue light from fluorescent lamps. This is unproven. But the direct impact of the LED lights on observed cancer rates, and the mechanistic understanding of how that works via the circadian rhythm impacts make that suggestive.

What is needed then to resolve this is the elimination of blue light from LED lighting, and the elimination of flicker. More over, to be effective the base of LED lighting already produced would need to be recalled and destroyed.

ALL of the energy used in the manufacture, distribution, recall, and destruction of these lights is then a sunk energy cost that cannot be recovered by using the lights through to the end of their lives.

Rather than saving energy, the conversion to LED lighting will have cost energy and worked against us in the battle to fight climate change.

Additionally, the Jevon's Paradox is fully on display. The intended reduction in energy use hasn't materialized because of the increased use of the lights compared to their predecessors and because of their use for new purposes.

But the simple idea that these lights are more efficient, therefor better, combined with the incredible complexity involved in understanding how light affects us, makes this a nearly impossible discussion.


Arctic sea ice / Re: The 2019/2020 freezing season
« on: December 16, 2019, 03:37:01 PM »
Watching that animation all I can think of is that the solstice is the 21st of December.

Arctic sea ice / Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« on: December 07, 2019, 02:22:39 PM »
Binntho, there will be no convincing you until events convince you, which IMO they will. But have you at least read or heard Bobby Kennedy's iconic GDP speech from 1968? GDP is now widely recognized as a deeply flawed measure that fails to capture much of what human beings actually value in life.  It's well worth a read. Here's an excerpt:

But even if we act to erase material poverty, there is another greater task, it is to confront the poverty of satisfaction - purpose and dignity - that afflicts us all.  Too much and for too long, we seemed to have surrendered personal excellence and community values in the mere accumulation of material things.  Our Gross National Product, now, is over $800 billion dollars a year, but that Gross National Product - if we judge the United States of America by that - that Gross National Product counts air pollution and cigarette advertising, and ambulances to clear our highways of carnage.  It counts special locks for our doors and the jails for the people who break them.  It counts the destruction of the redwood and the loss of our natural wonder in chaotic sprawl.  It counts napalm and counts nuclear warheads and armored cars for the police to fight the riots in our cities.  It counts Whitman's rifle and Speck's knife, and the television programs which glorify violence in order to sell toys to our children.  Yet the gross national product does not allow for the health of our children, the quality of their education or the joy of their play.  It does not include the beauty of our poetry or the strength of our marriages, the intelligence of our public debate or the integrity of our public officials.  It measures neither our wit nor our courage, neither our wisdom nor our learning, neither our compassion nor our devotion to our country, it measures everything in short, except that which makes life worthwhile.  And it can tell us everything about America except why we are proud that we are Americans.

An update from Freya Gletscher, E Greenland:
It has become quite cold. The sky is clear, but the valley with the glacier in it does not receive any sun beams, because the sun is already too low.
In that part of Greenland there are only a few cm of snow in the higher altitudes.
See attached photo.

Arctic sea ice / Re: The 2019/2020 freezing season
« on: October 19, 2019, 12:17:23 PM »
Even for the Arctic Ocean, we will be hard press to end the winter with at least a 2m first year ice, putting the risk of a memory of this summer. The islands on the russian side are nearing or breaking record which are only a few years old, like Ostrov Vrangel :

versus 2016 :

Or Ostrov Kotelnyj :

versus 2018

Or Ostrov Vize :

versus 2016 :

And again, a layer of low level clouds is keeping in check the refreze, as shown for example with Ostrov Vrangel between 300 and 600 meters since the end of the Summer :

And SSTs are still extrememly warm, locally up to 7 or 8 (!) °C. And with the clouds in place, cooling is going to be slow. It is a sure bet that southern Chukchi would not freeze before December or January, and it is increasingly likely that this sea could not fully refreeze before the end of the winter.
For now, the downward IR flux at surface is a bit less averaged over Arctic comapred to record holder 2018 and 2016, meaning a bit more heat is escaping the furnace of the Arctic. But we are starting with an ocean wich is way warmer than in 2016 or 2018 and to cool down this thing this small diff is not enough...

Arctic sea ice / Re: The 2019 melting season
« on: September 05, 2019, 09:16:47 PM »
August Area, Extent & Volume losses may have been low, but SST anomalies continued to climb and expand.
I wish I had saved the images from the beginning of the melting season. But I did not. mea culpa.

A quick search didn't reveal DMI's SST file locations. NOAA's SST products going back to 2015 can be found here with a link to the archives.

A daily, high-resolution, real-time, global, sea surface temperature (RTG_SST) analysis has been developed at the National Centers for Environmental Prediction/Marine Modeling and Analysis Branch (NCEP / MMAB). The analysis was implemented in the NCEP parallel production suite 16 August 2005. It became fully operational on September 27, 2005.
The daily sea surface temperature product is produced on a twelfth-degree (latitude, longitude) grid, with a two-dimensional variational interpolation analysis of the most recent 24-hours buoy and ship data, satellite-retrieved SST data, and SST's derived from satellite-observed sea-ice coverage. The algorithm employs the following data-handling and analysis techniques:
    Satellite retrieved SST values are averaged within 1/12 o grid boxes with day and night 'superobs' created separately for each satellite;
    Bias calculation and removal, for satellite retrieved SST, is the technique employed in the 7-day Reynolds-Smith climatological analysis;
    Currently, the satellite SST retrievals are generated by a physically-based algorithm from the Joint Center for Satellite Data Assimilation. Retrievals are from NOAA-19 and METOP-A AVHRR data;
    SST reports from individual ships and buoys are separately averaged within grid boxes;
    The first-guess is the prior (un-smoothed) analysis with one-day's climate adjustment added;
    Late-arriving data which did not make it into the previous SST analysis are accepted if they are less than 36 hours old;
    Surface temperature is calculated for water where the ice cover exceeds 50%, using salinity climatology in Millero's formula for the freezing point of salt water:
        t(S) = -0.0575 S + 0.0017 S3/2 - 0.0002 S2,
    with S in psu.
    An inhomogeneous correlation-scale-parameter l, for the correlation function: exp(-d2/l2) , is calculated from a climatological temperature gradient, as
        l = min ( 450 , max( 2.25 / |grad T| , 100 )),
    with d and l in kilometers. "grad T" is in oC / km
Evaluations of the analysis products have shown it to produce realistically tight gradients in the Gulf Stream regions of the Atlantic and the Kuroshio region of the Pacific, and to be in close agreement with SST reports from moored buoys in both oceans. Also, it has been shown to properly depict the wintertime colder shelf water -- a feature critical in getting an accurate model prediction for coastal winter storms.

     Description of changes effective November 1, 2016
        The analysis now uses satellite SST retrieval data from the GOES satellites. In addition, the values of "SST" over land areas are now generated by an SOR Laplacian solver, which replaces the legacy "weaver" code.
    Description of changes effective August 26, 2016
        Handling of satellite SST retrieval data in the analysis was modified so the analysis will proceed in the absence of satellite data.

    Description of changes effective July 15, 2015
        Hot spots in the Sea of Azov and Caspian Sea were replaced by more temperate values of SST. Cool Congolese waters were replaced using a climatology from Robert Grumbine.
Here showing sep4, 2015-2019 for comparison.
edit: dates were in the wrong order, forgot scale
@bbr - hudson bay quite cool the last 2 years

Arctic sea ice / Re: Latest PIOMAS update (July 2019)
« on: July 06, 2019, 07:33:01 AM »
Fram export  was higher than average in June.

Arctic sea ice / Re: The 2019 melting season
« on: June 16, 2019, 05:11:54 PM »
University of Bremen link still not operational.

IMO this is by far the best substitute for what you were looking for and for several reasons

try out the various features including large and very large image.

AFAIK the source is the same as well, hence no significant change of result between platforms to be expected

Arctic sea ice / Re: AMSR2 Snow & Ice Volume/Thickness
« on: June 02, 2019, 01:01:30 AM »
Volume continued below the mean, but thickness went up at the end of the month. It looks like the Beaufort gyre compacted sea ice against eastern Siberia and Hudson Bay ice was compacted against the southern coast.

Full size images and May animation at:

Policy and solutions / Re: Nuclear Power
« on: May 30, 2019, 02:35:04 PM »
New nuclear plants should not be built.  Existing nuclear plants should be maintained as much as possible until most FF plants are retired.

Arctic sea ice / Re: AMSR2 Snow & Ice Volume/Thickness
« on: May 03, 2019, 11:29:48 AM »
Another month of low overall gain, but above average thickness.

Full size images and April animation at:

Science / Re: Underground temperatures trends
« on: April 02, 2019, 08:52:07 PM »
A slippery slope: How climate change is reshaping the Arctic landscape article about study by Antoni Lewkowicz, University of Ottawa, published in Nature Communications
Increasing ground temperatures in the Arctic are indicators of global climate change, but until recently, areas of cold permafrost were thought to be relatively immune to severe impacts. A new study ... shows that areas of cold permafrost can be vulnerable to rising summer temperatures.

… recorded an astounding sixty-fold increase in the number retrogressive thaw slumps—landslides caused by the melting of the ice in the permafrost—on Banks Island over the past three decades.

Arctic sea ice / Re: Arctic Image of the Day
« on: March 23, 2019, 09:42:14 AM »
A pod of narwhal in the Arctic

Antarctica / Re: PIG has calved
« on: January 26, 2019, 05:56:57 PM »
Pine Island Glacier: 18 months of flow and calving

Antarctica / Re: Sea Ice Extent around Antarctica
« on: January 01, 2019, 06:36:02 AM »
It seems that the climate scientists have not come up with a generally accepted reason for this third year of much lower Antarctic sea ice extent, though there has been much speculation about this in this thread

The conventional wisdom (not just from Hansen by any means) is that as Antarctic ice sheet melt increases, additional fresh and cold water should encourage an increase in sea ice. The last 3 years data is in contradiction to that. I can find no science paper on this contradiction at all. When the GRACE mass data re-starts (from early 2019), perhaps this will tell us the extent to which the rate of Antarctic ice sheet mass loss has increased or decreased over the last 3 years.

Those still alive will see in another decade or two. Meanwhile, adding Hansen's latest mailing.
As yet the rate of freshwater injection onto the Southern Ocean may not have yet reached a level large enough to counter the loss of sea ice due to global warming, as judged from the large sea ice area reduction that has accompanied the warming of the past few years.

 Nevertheless, it is clear that amplifying feedbacks will produce increasingly rapid sea level rise if fossil fuel emissions and global temperatures continue to increase unabated. Even in the case of slowly changing paleoclimate forcings, ice sheet disintegration on a number of occasions achieved a rate that produced meter and multi-meter sea level rise in a century, confirming the existence and the potential large magnitude of amplifying feedbacks. Once the global warming effect on ice sheets is sufficient to strongly spur the amplifying feedbacks, we would expect the rate of mass loss by the ice sheets and the rate of sea level rise to grow nonlinearly, at a faster and faster rate.

 A capable means of assessing possible Greenland and Antarctic ice sheet mass loss became available with the first precise monitoring of Earth’s gravitational field from a satellite (Fig. 17). Early results from the gravity satellite showed shockingly rapid growth of the mass loss rates for both the Greenland and Antarctic ice sheets, for Greenland through 2012 and for Antarctica through 2015 (Fig. 17). Doubling times for mass loss rates were only of the order of a decade for both Greenland and Antarctica. However, in Greenland in 2013 and Antarctica in 2016 the rapid growth of mass loss was interrupted by a negative feedback: increased precipitation (snowfall).

 Decreased summer melt and increased snowfall over Greenland were associated with a change of summer weather patterns. The 2012 summer was characterized by sunny weather and a steady stream of warm air streaming from the south over Greenland, but subsequent summers have had a high proportion of cloudy days with moist marine air. Increased snowfall over Antarctica in the past two years was associated with reduced sea ice in the adjacent Southern Ocean, which coincided with rapid global warming during that period. The magnitude of the sea ice loss may have been related to the coincident strong El Niño. On the longer run, it has been predicted that increasing ice discharge from Antarctica, especially in the Western Hemisphere from the Ross to Weddell seas, will tend to cause an increase of sea ice cover, altering the precipitation feedback (see Fig. 16).

The rest / Re: Unsorted
« on: December 14, 2018, 10:48:08 AM »
When you mentioned Carson in February I downloaded it, no library nearby.

Permafrost / Re: Arctic Methane Release
« on: November 22, 2018, 06:02:17 AM »
During the Sangamon interglacial, rivers flowed north into the Arctic dumping organic material onto the shelves. At the start of the last glacial, ice dams formed, forcing the rivers to flow south. The sea level in the Arctic dropped exposing the shelves. The shelves remained exposed throughout the last glacial, and as the Holocene began, glacial meltwater turned the shelves first into a wetland, then with the rise of sea level, the shelves were submerged.

The permafrost that formed throughout the last glacial began to degrade even before the shelves were submerged as thermokarst lakes and rivers formed taliks. Much like is happening to terrestrial permafrost today.

Once submerged, the new warmer subsea environment, the salinity (think what happens when you put salt on a frozen doorstep), and geothermal flux from below, worked over the last 8,000 years to degrade the permafrost to the point that it now is pourous, and even totally gone in places, over an area of 2 million sq km.

Much of the methane hydrates that formed over the last 100,000 years since the Sangamon, dissociated, leaving a large reservoir of free methane gas under pressure, prevented from releasing only by the layer of permafrost which until now had acted as a cap.

Since the shelf is on average about 50 meters deep, any methane released does not interact with the water column, but releases directly to the atmosphere.

This is the end result of a geological process that has been going on for thousands of years and is a part of a natural cycle.

Over the last decade, the size of the areas releasing methane has increased and the amount being released has accelerated.

The release of just 1% of the available free methane on the shelf is enough to cause catastrophic warming.

Since there is no way to refreeze the degrading permafrost cap, the methane release is inevitable.  There is no way to shut it off.  And the methane will continue to release until there is no more left to release.   

Whoever is questioning the decades of observations and research conducted by Semiletov and Shakhova haven't got a clue.  Semiletov is the head of the far eastern branch of the Russian Academy of Sciences.  Dozens of scientists have participated in this research.   

If you have research papers providing rebuttal to their work, post it.

Just saying "some people say" doesn't cut it around here.
Here, we present research papers and discuss them.         


Arctic sea ice / Re: The 2018-2019 freezing season
« on: September 19, 2018, 03:34:20 PM »
In the freezer it goes, and I'll pull it out again once JAXA goes 25K above the preliminary minimum reached yesterday. Traditions are there to be respected.  ;)

Walking the walk / Well done but it's not over.
« on: September 08, 2018, 07:36:49 AM »
For my t-shirt hobby (it's far away from a business, I was looking for ideas to create a T-shirt about non violence.

I first arrived on the web site of the King Center that have an interesting glossary where I kept 2 key words :
  • Ahisma, which means more or less non violence (« a » for non and « hisma » for violence)
  • Satyagraha which is best defined by a quote “Satyagraha is literally holding on to Truth and it means, therefore, Truth-force. Truth is soul or spirit. It is, therefore, known as soul-force.” M. K. Gandhi

When googling both words, I followed different links and had the feeling that in Gandhi’s concept, holding on to the truth seems more important than non violence. Non violence would be to be the way to act, but holding the truth is the corner stone that is required if non violence is to be used.

About satyagraha, I found 2 interesting links,

Here are some quotes

"Gandhi believed in the scientific method of:
  • accumulation and presentation of evidence;
  • review of the logical processes employed for arriving at a conclusion;
  • joint examination of these processes and evidence;
  • replaying that tape by which one has arrived at a conclusion so that one may detect the point where divergence commenced;
  • investigating whether the refusal to see evidence and logic is the result of ego-centric attitudes and perceptions and if it is found that this is what leads to intransigence, then
    divesting oneself of ego-based considerations that have only a limited place within the unalterable paradigm of interdependence that rules humanity;
  • reassuring the “adversary” that the effort is not to deny his needs and interests, while promoting introspection in the adversary through love and the readiness to suffer (voluntary suffering).

In spite of all these efforts on one’s part, one may not be able to dissolve intransigence on the other side. Such a situation where all efforts of persuasion seem to have failed would demand Direct Action."

"Nonviolent non-cooperation and Civil Disobedience can be effective only if operational conditions are controlled to prevent the outbreak of violence, and loss of control by the leadership of a struggle. Gandhi firmly believed that two antagonistic forces could not work to supplement each other. »

I just wanted to say that it looks like we are doing a good job, that it is important to go forward. I feel that always more people are aware that things have to change. I believe that we are right, that we have to hold to it and that, walking the walk, we are somehow doing a direct action to change the game. Let's continue.

Arctic sea ice / Re: 2018 sea ice area and extent data
« on: July 15, 2018, 11:47:14 AM »
Thanks Geron!

They also have a great 10 day ice concentration map that I like to keep tabs on.

Click image to play

Arctic sea ice / Re: How soon could we go ice free?
« on: June 18, 2018, 12:25:28 PM »
I think Figure 1 from Tietsche et al 2011 is important.

This shows two things - firstly, the general shape of the (modelled) decline in Arctic ice over the coming decades, and secondly the time taken to recover from extreme events such as the summers of 2007 and 2012.

For the latter, the conclusion is quite simple - the Arctic has a "memory" of about two years, and so any major excursion will bounce back to the long-term trendline within a couple of years.  They only modelled downward excursions, but my guess is that it holds the other way too - even if by chance we have a particularly good year for ice retention, it'll be gone in another couple of years.  The paper discusses the mechanisms for this, but fundamentally it's quite simple - if you have a massive loss of ice one autumn, that means a correspondingly massive extra heat loss in the following winter.  By the end of spring, first year ice has grown back. A low summer minimum has very little effect on the following maximum.  This is believable, and we've seen it after every major loss year for more than a decade now.

For the longer term decline, look at the shape of the curve.  Note how it's staggered and stepped.  This reflects the shape of the Arctic ice basin. There are shallow seas around the edge, and a deep central portion that covers about 5 million square km. So, as ice loss progresses, there's an initial period of rapid decline that plateaus at around 4.5 to 5 million until about 2020.  That's exactly where we are now, in that plateau, where the summer minimum roughly covers the deep parts of the Arctic Ocean but the peripheral seas melt out each summer. Subsequently, there's another period of rapid decline that plateaus again at 1.5-2 million.  This is the "remnant above Greenland" stage.  The final collapse comes after that.

The shape looks entirely plausible to me, all that we need to work out is the scaling on the X axis, and to be honest I'd be surprised if they're far off. Right now we're on the verge of the second period of decline - but it'll plateau again in another couple of decades, probably before hitting the "ice free" threshold of 1 million.

It may be we need to squash the X axis up by 10% or so to fit reality - someone with more time than I can probably make an overlay - but it's really not far off.

Arctic sea ice / Re: 2018 sea ice area and extent data
« on: June 16, 2018, 05:51:27 AM »

June 15th, 2018: 10,236,731 km2, a drop of -81,224 km2.
2018 is the fifth lowest on record.

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