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Messages - Rubikscube

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Consequences / Re: COVID-19
« on: August 01, 2020, 12:33:36 PM »
The study also found that a large section of people had been infected and survived with no or little symptoms, leading to a low fatality rate in these areas - one in one thousand to one in two thousand. This also lowers the city-wide death rate from Covid-19.

And more women were found to have been exposed to infection by the virus in both slum and non-slum areas.

more on:

This is very important work which I wish was done in many other places, including villages. As for the assertion that the fatality rate was 0.1-0.05%, I find that extremely dubious (unfortunately BBC does not actually link to the survey they cite. I don't know if this is standard BBC practice, but it leaves us at the mercy of BBC's interpretation). Presumably, dead people were not tested for antibodies and I doubt very much that reliable population-wide death records exist for the slums in question, which means a lot more work needs to be done to find the actual death toll. Having stayed in city slums, impoverished villages and countryside slums (they do exist where agro-business rely on dirt cheap migrant labor), I don't have a very hard time imagining that deadly outbreaks went un-reported. Government presence would have been nonexistent in the first place, so people in such places does not assume that the government will help them when they get sick, and are not inclined to post distress messages on social media to call attention to their plight. In fact, a lot of people will be ashamed to have been infected, and are more likely to low ball the suffering they and their relatives have undergone.

Here is an extensive journalistic report from the outbreak in northern Nigeria a few months back, which will give you some idea of peoples mindset towards the pandemic;

Lockdowns are clearly ineffectual and counter-productive in many areas, such as Mumbai slums. There are, however, a bunch of countries which are perfectly well placed to deal with this pandemic, and their failure to do so is inexcusable (*looking towards America and Europe*). bbr's assertion that the virus cannot be stopped is simply false. Wuhan stopped a much larger outbreak than the one in Melbourne. They succeeded because they didn't move the lockdown one inch until the number of new cases was 0 and remained at that for several days. Later the whole city was tested again. A number of different countries, with vastly different strategies, government and socio-economic systems has managed to stop coronavirus in its tracks (most of them in East-Asia). I never seize to be shocked that restrictions are lifted in places where new active cases are being reported every day, only for people to be surprised that the virus returned. After 6 months of this shit, it seems people (and people making the decisions) haven't learnt the most basic stuff, like the fact that this disease is contagious and can spread through the population undetected for several months. Bottomline; Covid-19 does not spread because of magic tricks, it all comes down to policy failure. Policy failure over the course of several decades.

Here is part of what policy failure look like in Italy (and I suspect most of the western world); overwhelmed public hospitals selling patients to private clinics and nursing homes.

Here is part of what policy failure looks like in the 3rd world; rich donors paying corrupt policy makers to defund public health care (and every other public service, including democratic governance).
(no wonder the liberal establishment would rather ignore coronavirus in Africa so they can focus on "Black Lives Matter")

Thanks to all the people posting interesting stuff here, in particular Vox Mundi. i think this is a great Covid-19 thread.

Arctic sea ice / Re: The 2020 melting season
« on: July 30, 2020, 07:43:00 AM »
How did the 2012 GAC look on false color as a comparison?  I am a relative newby and did not start following the melt season till a couple of years later.  Is that available to look up on the Bremen site?

You can find the live coverage of the GAC 2012 in the archives of Neven's blog. There are several Uni-Bremen false color gifs for comparison there. Ice concentration was notably lower in areas affected by that storm, which I believe make a lot of difference to the outcome. Powerful August storms in 2013, 2014 impacted high ice concentration areas and had much the opposite effect of GAC-2012. It is interesting to see what the impact will be of this storm.

Arctic sea ice / Re: The 2020 melting season
« on: July 26, 2020, 08:07:13 AM »
Warmest temperature ever recorded on Svalbard yesterday. 21.7 C that is, and more to come. Previous record temperature for Eureka is 20.9, also looking to fall (the forecast attached says Eureka, N.W.T, but map coordinates show it is Eureka, Nunavut). Link to Canadian gov temperature records from Eureka.

I suspect record melt is ongoing across CAA and much the Atlantic side up to the pole.

Arctic sea ice / Re: The 2020 melting season
« on: July 07, 2020, 11:42:31 AM »
OK...what is epic about the 10 day forecast? I see a temp forecast at 850 hpa. Google tells me this is generally about 1.5km above sea level, above the boundary layer.

If I open the GFS forecast and look what's doing in 10 days at sea level, I see the warm spots wherever this is open water in the forecast and all the ice covered areas are actually pretty mild at 0.0 - 1.0C.

The surface temperature of melting ice is always going to be zero until the ice has melted and turned into water - that's thermodynamics - therefore surface temperatures from the ice are not going to tell you anything about how fast the ice is melting. That is why we use 850 hpa temps, because they are not affected by the ice and can tell you something about how much heat there is in the atmosphere. Yes, 850 hpa is 1.5 km above the surface and can in rare instances be misleading, but you'll need a very concrete reason to think so. Peolpe will even use 500 pha temps sometimes.

Regarding 2013 pole melt. 2013 had the exact opposite setup of what we have now. Back then a very persistent cyclone stuck around the north pole for so long that the ice dispersed to the point that it became visible in satellite images (for the same reason that the current anti-cyclone is compacting the ice). Fresh from the GAC-2012 a lot of people, myself included, thought this would spell doom for the ice, but as is usually the case, the cyclone kept the temperature low and actually helped preserve the ice (2013 was by all metrics a huge recovery from the year before). What we see in images right now is ice at the north pole melting in-situ. What we see in images from 2013 is ice at the north pole dispersing from wind action. 

Arctic sea ice / Re: The 2020 melting season
« on: July 04, 2020, 07:41:33 PM »
2014 had a similar HP pattern, so comparisons are somewhat warranted. The big difference is that back then there where no heat import, just cold air circling around. 850 hPa temps were 5-10 C lower than they are now, and there was a lot of snow in the buoy-pictures which took forever to melt (the buoy thread seems dead now. I've been away for a while so I don't know why, but the 2014 pics will still be there for comparison). I think this is a pretty uniquely awful setup which does not come around very often. Unprecedented in the post-2007 era.

Arctic sea ice / Re: Temperatures at Eureka, Nunavut, Canada
« on: June 29, 2020, 11:50:13 AM »
this is the hour by hour recording from the Canadian gov website - cited on Wikipedia - yesterday was just 0.1 C short of the all time record.

Arctic sea ice / Re: Temperatures at Eureka, Nunavut, Canada
« on: June 29, 2020, 11:39:04 AM »
Weather forecasts for Eureka supports the notion that there are +20C temps there, and will be for another 48 hours. Don't think it is an error, just very warm.

Arctic sea ice / Re: Latest PIOMAS update (August)
« on: August 04, 2017, 03:51:59 PM »
"PIOMAS appears to overestimate thin ice thickness and underestimate thick ice"

Edit: Have a look at this figure (Fig. 4b):

The curve appears to shift to the left over the years. If that trend has continued, does it not imply that PIOMAS may now be overestimating ice thickness even more? Anyways, something to keep in mind.

I might be horribly wrong here, but I thought PIOMAS had been updated to address this specific issue. Can anyone confirm or refute that?

Arctic sea ice / Re: Latest PIOMAS update (August)
« on: August 04, 2017, 03:43:39 PM »

My point is; when you have a well-documented model, like PIOMAS, you should start by assuming that this model is indeed functioning properly and produces a reliable output, and that in doing so you do not submit blindly and willfully to said model (People should not have to explain that last point every single time they make the case that the PIOMAS output is reliable). Of course, you can challenge this model, but to do so you need some kind of hypothesis, and preferably, an objective reason to challenge the model in the first place.

Let’s for the sake of argument make the, in my subjective opinion, dubious assumption that this melting season is something special and different (the 2017 melting season as modeled by PIOMAS, not the 16/17 refreeze, not the melting season that has yet to come), it’s a situation that will arise sooner or later anyway. First question is; are there any factual reasons to assume such conditions will impact the accuracy of the model? Any documentation that the model performance declines with increased melt ponding, more rain, wave action etc? greatdying2 provides one such factual reason in his reply to me, while the comment I originally responded to provided none whatsoever.

Now, you might argue such documentation does not exist because of the unprecedented nature of the present situation or because no one is funding arctic research these day. Whatever it might be, let’s again - for the sake of argument - assume such claims are valid. Still, there needs to be an objective reason for calling into question the reliability of the entire model, and if the only thing you have are the model output, then use this to make your argument. Is the data behaving in an erratic or arbitrary manner? Is the modeled data directly conflicting with other available data (such as satellite imagery)? Demonstrate it, show us, explain. Use the simplest of linear regression models, or whatever, present it and see if your hypothesis can withstand some scrutiny. Because I can’t see what is so wrong with the latest batch of PIOMAS data.

This is “just” a forum, most people who come here are just casual observers – like myself – and I’m not saying you need to spend hours, day, or years formulating and testing scientific hypothesis’ to be allowed to post here. But if you are going to make grandiose claims, challenging the fundamental reliability of rigorously tested models, then you should damn well be held to the same standards as the people you are challenging – in this instance the Polar Science Center.

Arctic sea ice / Re: Latest PIOMAS update (August)
« on: August 04, 2017, 10:17:54 AM »
It is quite remarkable how the volume trajectory keep tracking 2014, that year also had a remarkably warm winter, heavy snow cover and lots of ice in the Barents. Could this be an indication on melting patterns in case of warm winters and heavy spring snow cover, or is it merely coincidental?

Arctic sea ice / Re: Latest PIOMAS update (August)
« on: August 04, 2017, 10:12:26 AM »
I highly doubt that this is accurate.
All those melt ponds, floes, rain could have tricked the sensors.

I only say, that Jetstream activity- & record extreme weather events just don't fit with those "high" Volume numbers.

PIOMAS is an ice volume model - whose numbers are derived from multiple sources of data, not any particular "sensor" - and the far superior one, by any scientific standard. I would strongly recommend you to adjust your personal perceptions so that they fit certifiably accurate data, not the other way around - adjust the accuracy of data so that they fit your predetermined personal perceptions.

Besides, there is nothing particularly extreme about this melting season, and this seems perfectly reasonable to assume that volume and extent/area measures would realign again as minimum approaches.

Arctic sea ice / Re: The 2017 melting season
« on: July 24, 2017, 02:30:47 AM »
I bit the bullet, stacked one week of images from the eastern Arctic and removed the clouds manually (took hours).


Arctic sea ice / Re: IJIS
« on: July 08, 2017, 06:25:38 PM »
Extent is doing exactly as I have been predicting and voicing reasons for the opinion. It is a far more mobile pack than we've seen before. And the extensive fragmentation and high salinity has been causing temps to be supressed as it melts in place instead of from tje edges. More hot steamhoses ate predicted. I would expect to see double or triple century drops regularly stsrting in  a few weeks.

Thats fair, I personally think the pack looks more fragmented on pictures from last year, but thats just my opinion, it - the pacific side - is certainly thinner than ever. Still don't think there will be double and triple century breaks though, considering that IJIS isn't prone to the same day to day fluctuations we see in CT and even Wipneus' numbers.

The odds? I'd give 2,2 for a double and 50 for a triple. No, I'm not taking any bets on that :)

Arctic sea ice / Re: IJIS
« on: July 07, 2017, 01:57:02 AM »
@Hyperion. PIOMAS is the superior model when it comes to ice volume, so stop misleading people by pretending the accuracy of HYPCOM-thickness is even comparable. Why are you cluttering the IJIS thread with this nonsense in the first place? There are several threads dedicated to volume models. And please - this apply to multiple people - stop concern-trolling the legitimacy of the extent measurements every time extent drops fails to meet your expectations. IJIS has time and time again proven a great asset to us casual sea ice observers.

Arctic sea ice / Re: What the Buoys are telling
« on: July 07, 2017, 01:29:28 AM »
Its a well know phenomena in world-view imagery that ice which turns blue, from melt ponding, will again turn white then gray before it melts completely. I believe that is what we are seeing here, grayish skeleton ice which will struggle to survive another couple of weeks in this weather.

Arctic sea ice / Re: The 2017 melting season
« on: June 26, 2017, 08:38:17 PM »

And your point is?

the point is that every post that tries to reduce the gravity of the current conditions as well as development over recent years leaves a bit of a smell of bias and/or talk just to talk or contradict just to be heard.

Haha, I first came here to comment (#2288 ) on what a scorcher this melting season is now setting up to be. Then I'm asked to answer for my moderating bi-sentence, and in going so subsequently being accused of contradicting the common narrative just to grab attention (trolling?)? Anyway, Seaicesailor gets my point - and makes a good summary of the situation - if you don't, lets just agree to disagree (just don't come back in September and tell me "I told you so" :) ).

Arctic sea ice / Re: The 2017 melting season
« on: June 26, 2017, 05:29:57 PM »
Except that the Arctic Ocean is currently the lowest volume on record is it not?

And your point is? Read my comment again and find that no one disputes that 2017 is still in contention for record minimums. The fact is that all the volume deficit you refer to is the result of the disastrous 2016/17 refreeze and got nothing to do with this melting season. Rather to the opposite, since 1st May - the start of melting proper - net volume loss have been comparable to 2014, allowing the difference to all the front runners (2010, 2011, 2012 and 2016) to shrink substantially. Relative to the last 7 years, that is called a slow melt.

Every year since 2012 the same thing happens, some people fall into the optimist bias trap and start looking for confirmation that this is going to be another record breaker instead of trying to analyze the data objectively.
"Fortunately"? Why it'd be "fortunate"?
I believe the general arguments for that can be found in another thread, but I'm not gonna pretend that I have any moralist qualms about being exited by the prospect of new record minimums.

Arctic sea ice / Re: The 2017 melting season
« on: June 26, 2017, 07:46:56 AM »
I'm confused why you think this is a slow melting season when Wip's numbers show that the CAB is at a record minimum area for this date, and I think we are around third lowest for extent on NSIDC. Surely a slow melting season would have us at above average extent?

Because 2017 had a headstart on both SIE and volume, which is no longer there. May extent loss was an unimpressive 12th smallest, June has been a little quicker, relative to other years, but still far behind 2012. The snow cover was slow to melt, melt ponds came late and there hasn't been much melt momentum - until now - just a steady chiping away of ice which was record thin and weak to begin with. 2017 would end nowhere close to 2012 minimum if this trend contiued another month. Fortunately, it wont.

Arctic sea ice / Re: The 2017 melting season
« on: June 26, 2017, 12:53:31 AM »
Its time to sound the dipole alert! A pretty slow and uneventful melting season, thus far, is about to get a lot more interesting. The attention grabbing storms, which once more prove unable to aid ice loss in high concentration ice fields, are about to be replaced by its silent, but far deadlier counterpart; the arctic dipole . This setup has consistently stalked the ECMWF forecasts for a week now and has finally entered the reliable 72h range, where it is predicted to stay all the way through 240h. It remains to be seen whether a proper dipole will last for 2-3 days (highly likely) or 7+ days (plausible, but less likely), but the latter of the two scenarios is bound to be an unmitigated disaster.

Arctic sea ice / Re: The 2017 melting season
« on: June 13, 2017, 07:21:23 AM »
This seems simple enough to me; more late spring snow + less melt ponding = retarded ice melt. Past observations supports this pretty clearly. Of course, the situation can change rapidly and a different preconditioning with record low spring volume may impact the outcome, but beware of attempts (conscious or unconscious) to over-complicate or downplay the impact of more snow and higher albedo to support a narrative of imminent collapse. It is far from guaranteed that there will be new record lows this year, if the volume trajectory follows that of 2014 the September volume will be 5th lowest between 2013 and 2010, and there are early signs of a 2014 syndrome developing - lots of snow and a awkwardly situated HP which (presumably) removes insulation without really contributing any heat influx. I think this season will be very instructive in determining the impact of weather vs climate on annual sea ice loss, since short term variables seems to be favoring less melt, whereas long term variables seems to be favoring rapid melt.

In that regard I would also ask people to please stop posting 5-10 day weather forecasts, especially the GFS non-ensemble forecasts which has repeatedly proven to have ZERO value beyond 5-7 days. This is just speculative nonsense, or even worse cherry picking of model runs which support a desired outcome/narrative.

Superb work Tealight.

Arctic sea ice / Re: The 2016 melting season
« on: August 19, 2016, 01:51:32 PM »
Amazing. Now can the SIA crash be sustained on a slightly weaker storm alone, with no help from 925 hPa temps? The next 2-3 days will be really interesting in that regard. It doesn't look like we're going to get a new 953 pHa storm (that's a pretty sick forecast), but instead it looks like a dipole may be on the horizon, which could be just as devastating.

Arctic sea ice / Re: The 2016 melting season
« on: August 16, 2016, 11:20:22 PM »
Geee, this is exciting, though I have a suspicion it will and with no significant cliff, for the following reasons: this is 10 days behind GAC-2012 and the ESS-tongue has proven very hard to melt in the past, temps are cold and will go even colder in the aftermath (GAC lingered for a few days, but was relatively quickly replaced by a dipole) and this is "just" 968-969 pHa with epicenter further to the north. I won't claim to know, lets say 70-30% on stall or no-effect vs. crash, could go either way.

Arctic sea ice / Re: The 2016 melting season
« on: July 05, 2016, 06:44:56 PM »
The fresh PIOMAS numbers confirms again the extremely strong and perfectly logical correlation between arctic 925 pHa temps and actual ice melt, and once more go against the nonsense, wishfull saying that "extent doesn't matter", which seems to pop up whenever extent loss stalls.

Weather patterns are about to change though, Beaufort and CAA are currently under heavy attack from powerfull heat, which should spread across all western hemisphere arctic within 72 hours. This kind of -ve NAO assosiated dipole has arguably been the most melt favoutable setup of them all in the past, featuring strong heat influx and ice compaction. The resilience of "big block" and other MYI Beaufort floes will be tested for real.

Arctic sea ice / Re: The 2016 melting season
« on: June 23, 2016, 12:08:14 AM »
This will change over the next few weeks. HYCOM shows the split in the pack becoming more pronounced and legitimately spanning from Canada to Siberia. As the pack splits in two, and as we see storms traverse the split, I think the chances of a completely ice-free Arctic this year are increasing quite dramatically.

The pack is not going to spilt from Siberia to Canada, period. What can happen is a larger part of the pack detaching from the rest in the ESS, after all it did happen in 2012, and this year with lots of thick ice stacked up against the far east siberian coast it may very well happen again.

Secondly melt favourability is not really a question about HP vs LP or coulds vs sun, it is basically a question about heat influx vs no heat influx. It is just that a LP dominated arctic tend to isolate cold arctic air masses whereas the opposite is often the case with HP domination, occasionally it will work the other way around, as in 2014 when prolonged HP domination failed to create any WAA at all, or as in the case of this most recent storm which did, and still is, spurring offshore winds and sucking in warm air fronts on is back, possibly causing some lethal rain-to-ice-action. Heat is what cause the ice to melt, not barometer preasure.

Good thing it's that early within melt season, i think. Shouldn't be much damage done. If the same thing would happen August, we'd see quite a punch, eh.

Storms does not automatically do more damage towards the end of the season, in 2013 a barrage of powerfull 970 pHa storms coincided with a spectacular August stall in area, extent and volume loss. Events in late 2011 and 2012 suggests that the ice consentration need to be below 50% if there is going to be significant "flash melting" with accompanying SIA drops from storm and wind action, otherwise heat influx and ice compaction will have to be present to cause damage.

Arctic sea ice / Re: The 2016 melting season
« on: June 13, 2016, 04:41:25 AM »
Attached below is the Uni-Bremen map for June 9 2016, a map showing average ice consentration for the same date 2002-2015 (based on the same amsr2 and amsre maps provided by uni) and a map showing the relation between 2016 and the average (red indicating lack of ice, and blue the opposite)

Evidently, Beufort is still way ahead, together with Barents, Kara and Greenland sea, Siberian fast ice is also melting early, though the ice consentration here and in CAA can be somewhat misleading at this point of the season. Crusual regions such Chukchi and Laptev aren't melting ahead of time though, and with the current weather and weather forecasts, 2016 just isn't going to beat 2012. The setup for a new record was perfect 3-4 weeks ago, but the chance has been blown, and a 2015esk turnaround in melting conditions will be needed to give 2012 a run for the money. Any talk about how low preasure and divergence should be bad for the ice is wishfull thinking, it has been demonstrated time and time again during the past few seasons. Also worth noticing that ice was continously being exported towards Svalbard and Frans Joseph during the 2014 summer, then coinciding with a spectacular lack of volume loss, I dont see why it should be very different this time, it only keeps ice out of the far more efficient ice killer that is Fram strait.

Science / Re: Adapting to the Anthropocene
« on: March 19, 2016, 05:06:26 AM »
Thanks, Rubikscube. This sounds at least quasi-intelligent. But I guess the perceptory apparatus (e.g. database scheme) is still custom made. Would be interesting if this machine can easily be re-wired to play chess. (BTW I know of a 3-player chess. That might be a better test than Go. It is not a duel but a triell...)

Haha, it may indeed be more quasi than intelligent, an honest try though. If I understand this correctly Google DeepMind (the company behind this) claims that AlphaGo wasn't initially programmed to play Go specifically (or make the computer teach itself this specific game), but is rather a learning algorithm specifically trained at Go, which could technically learn to play other games if was fed with such information. I do indeed agree that putting a computer like this into a multiplayer game is an intriguing idea.

A basic introduction to neural networks

and a very lengthy and comprehensive one (a book actually)

Science / Re: Adapting to the Anthropocene
« on: March 19, 2016, 12:11:17 AM »
What is the intelligence in this Go program? Any strategical plotting or some theory of mind? I guess it's still just specialized algorithmic brute force. Can a Turing machine become intelligent? Can one construct a mechanical philosopher? -- My hunch is you have to go beyond mechanics and build organismic "wetware" to make matter intelligent.

AlphaGo is not a "brute-force" searching program. It applies neural networks and is technically a "deep-learner" who taught itself Go by independently analyzing a database of games as well as playing a vast number of games against itself. This approach is basically about mimicking biological brains, adding features such as short-time memory to a computer program. I did in fact recently have a lengthy argument with a programmer working with neural networks about whether a computer program could beat a selection of the world’s best poker players in a similar competition setup. Insisting it cannot happen anytime soon, though, unfortunately having to concede that it is just a matter about when, and not if, an AI entity will be able to outperform a human being in any given type of work (yes that includes all work related to love and friendship. Considering how easy it is to make a human emotionally attached to something as simple as a stuffed animal by just adding a symmetric, humanoid face with big eyes, I find it is astounding that people can believe otherwise).

The problem with computers and robots is not that they eventually will rebel against their human masters, rather the opposite, a computer does exactly what it is told to do, thus theoretically enabling one person to create for himself a perfect totalitarian singularity (the endgame of pure Darwinism (rebranded libertarianism)).

The rest / Re: 2016 Predictions
« on: December 30, 2015, 02:39:47 PM »
I predict there will be an epic drought in the Amazon rainforest, such as has become the custom during recent El Niño years. Water levels are currently 3 meters below average in Manaus.

The pineapple express will hit California sometime in January killing a 4 digit number of people and resulting in the most expensive natural disaster in modern history.

Arctic sea ice / Re: What the Buoys are telling
« on: August 27, 2015, 01:59:07 AM »
Wow, nice catch diablo.

If those red dots where to melt by minimum, then there should be a really significant drop in SIA and SIE yet to come. But I agree that 2015F will very likely survive. Very interesting to see this much bottom melt far beyond the ice edge.

Policy and solutions / Re: Can We Save Capitalism?
« on: August 26, 2015, 01:36:11 AM »
Can capitalism be saved? No, it can't, nor can we make capitalism save for that matter. The human nature simply does not permit that to happen under any circumstance, regardless of whether your definition of capitalism includes the softer, saner version which allows for some degree of central regulation or whether you insist of the hardcore, lunatic libertarian version, which is basically another way of describing an anarchy.

As soon as any land and any means of production become someone’s private property, the tumble down the rabbit hole begins; an upper class is born which will continuously keep using their accumulated wealth to press for more wealth and power, and somewhere along this path towards absolute totalitarianism the system will usually destroy itself (if it is not destroyed from outside), be it eco disasters, upper class power struggles, rebellions or a combination of all these and more.

Fine, stay home then and read the adventure blog. WorldView for 25 Aug 2012 below.

Hehe, I certainly won't be dragging my sorry ass into that minefield, not sure your helicopter guy will agree to ditch you down there either, even if you pay him ever so much (like I said this is not Mexico).

Say whatever you want about Google, but they do actually got street view from the outer island towards the south branch, they have even bothered to walk up several "streets" as well, and from what I can see, the main ice stream remains pretty much visible all the way up to the bend (the light makes it a bit difficult to judge). A camera there should be able to monitor the calving front for many years from now given that JI doesn't start retreating at absurd speeds.

Back to the volume vs elevation plot, I promised an estimate, but I'm not able to draw even a crude 2000 m line in their elevation plot. I will see what I can do with the cdf, but most likely I'm too much of a programming noob to make any sense of it.

The best vantage point really is the divider between north and south branches. While this looks like a crazy unstable icefall, several years of Landsat show that it is very stable. It would take a helicopter to get there and, if Greenland is anything like Mexico, you would not want to pay the return fare in advance.

Whoa, hold your horses... you mean like camping on Cape Ice? Those crevasses aren't harmless just because they aren't moving. I presume you will have to scout a location in advance at least (that would be some additional expenses on worldview imagery i suppose). Fortunately, I imagine every country in the world to be more like Mexico than Greenland :D.

It's amazing also how much more exposed rock there is.

The 2014 minimum occured in late September, so notice that the high ground was covered with fresh snow back then. When comparing to summer landsats from June, July 2014 futher up in the thread you have to look really close to find any significant difference at all. During a decade or so it will accumulate into a sizable amount, but from year to year retreat is still painfully slow.

I am under the impression that mega calvings like these usually occurs in June and July, so is it just a coincidence that this one is rather late? The "ramp and sill" image (Joughin et al 2014) posted by A-team previously this summer, indicates to me that we might have jumped over the bump in this latest calving.

What could have been a walk in the park becomes a whole lot messier when every thickness map within reach features a myriad of different color contours rather than a nice and tidy little color palette. Or is it just me looking at the wrong places? Well fortunately, when taking a closer look there turned out to be more system in this color anarchy then what seemed at first ("anarchies" often work that way), so it was eventually possible to narrow things down to a handful of specific contours, each representing a thickness.

However, there are problems with this approach, most notably; the pure colors (red, yellow, cyan and blue in this instance) merged with and were eaten by their less pure neighbours so to speak. This effect becomes particularly visible at low elevations where the slope is steeper and the different colors are crammed tighter together. Then, for some reason (I'm tempted to say god knows why, but I'm not sure he does this time) there turns out to be 36 different contours, for one 32 would have fitted perfectly into their color system, as opposed to the current solution which tries to divide 256 on 9, but more importantly it would allow each contour to represent a leap of exactly 100 meters, as opposed to 88,1m which I got from pixel counting their color scale (which by the way measures 241, a prime). Is this because 88 meter fits some margin of error or something like that, or do they just want to mess up the diagrams of excel noobies like me?

Either way I have managed to produce a couple of diagrams that resembles those who were requested, although it is not volume vs elevation, which I agree would be better, but rather volume vs thickness. I'll do the elevation as well, but if someone happens to jump across such a map that doesn't feature every possible RGB combination, that would be helpful and it would enable me to do a bit more than just setting a crude line at approximately 2000m (the same goes for the thickness map of course). Note that I have been treating the individual coutures as ranges which means the volume calculations are based on the medium of these ranges, please let me know if I've gotten that wrong. In this calculation the 2000 meter boundary splits the volume 35/65, give or take a percentage or two.

Click to enlarge.

What I still don't get about Jakobshavn is why there is so little interest in the areas east of the currently active main channel. Morlighem shows there are multiple channels hundreds of meters deep stretching for hundreds of kilometers inland, even though those areas appear inactive today there must surely be possible to extract some useful information about the past and future behavior of Jakobshavn by taking a closer look at them. I mean, how can scientist make an even remotely accurate estimate of JHs future contributions to SLR if something like 90% (probably more) of its drainage is ignored? Have they virtually just given up on JH because the main channel more or less inaccessible?

The politics / Re: Empire - America and the future
« on: August 11, 2015, 12:44:38 AM »
A somewhat different article about Trump.

NB: link expires after 48 hours (if it works in the first place).

Arctic sea ice / Re: The 2015 melting season
« on: August 09, 2015, 10:33:24 PM »
I also agree that the melt season will probably run a week longer; I'd actually hazard it may be two to three, and that we may not see a minimum until after 1 October.  It depends on two things I think; continued high SST's along the periphery of the pack, and import of heat from further south via the remains of east Pacific cyclones.  The first will provide the necessary heat for continued melt; the second will offset radiative losses which normally would reduce the effect of the first.

I don't see any reason to believe there will be a late minimum this year. CT area numbers show no trending toward later minimums and I don't think you will find much correlation between low and late minimums either. If anything, I would say the high presence of low concentration areas filled with slush and ruble favors a slightly early refreeze this year.

Arctic sea ice / Re: The 2015 melting season
« on: August 09, 2015, 12:21:07 AM »
What do people think of this?
I saw the maps for Aug. 7, 2015 and 2012, and I thought they look very different, so I made this graphic to show what I mean.
Am I imagining it? With at least a month to go, will this make a difference in the final outcome?
If the melt season extends longer and warmer, which I think it will due to global record heat being set all over the place, can these weaknesses amalgamate and cause a break up of the ice sheet into 3 or 4 big parts?

I think the resemblance between 2012 and 2015 is striking, the pack will look very much like 2012 at minimum I imagine, only larger. Not sure whether the areas labeled "thin" really are that much thinner though. The pack won't break up into 3-4 big parts, but this season in general has been marred by unusually large attachments from the main pack and a long total ice edge, this latest one in Beaufort and Chukchi is rather unprecedented and very fascinating to watch.

Slow wing, I much appreciate the daily uni-bremen update of yours, keep it coming please. Adding some fade definitely makes it better though.

Arctic sea ice / Re: The 2015 melting season
« on: August 06, 2015, 01:17:04 AM »
“The > +4dC anomaly North of Ellesmere through July hurts where it is worst. In this 350K km2 the heart of the remaining MYI is losing volume at freightening speed.

The scattered remains of the Ellesmere Ice shelf must be suffering in these temps too. Modis shows the Ward Hunt Shelf is turning gray and dark, similar to what happened in 2012. I wonder for how many more decades these shelves can cling on.

Arctic sea ice / Re: The 2015 melting season
« on: August 03, 2015, 10:49:31 PM »
Attached below is the average sea ice concentration map for 2003-2014 (NB! the baseline is different from previous posts this season as 2012 for this date is available in AMSR2 and 2002 for some reason isn't available at all). The other two maps display 2015 vs average and 2015 vs 2012 respectively, with reds indicating a decrease in sea ice and blue meaning the opposite. All data is 1st August from Uni-Bremen.

It should come as no surprise, given the SIA/SIE numbers, that this year is currently well below the 2003-14 average. ESS, chukchi, Barents and Kara are mostly in the red, but the situation appears more mixed in Laptev, Beaufort and CAA.

2012 still seems quite far ahead though, even excluding Hudson and Baffin. I have a hard time imagining how 2015 is supposed to beat that year, also CAA is way behind, which is perhaps somewhat surprising given that this area has been subjected to intense heat this July, but not unheard of either given that there is significantly more MYI there now compared to 2012.

Regarding the SST discussion, I'm most exited about the intense anomalies in Kara. The first time Kara melted so early and scooped up such loads of heat was 2011, then it seemingly took Kara 18 months to recover (That is considering the 11/12 refreeze failure and subsequent early meltout in 2012 to be directly related to the 2011 crash, which may not be correct)

Arctic sea ice / Re: Arctic Image of the Day
« on: August 01, 2015, 11:00:03 PM »
Another beauty shot from Obuoy9 yesterday. Not even nat geo can do very much better than this.

Antarctica / Re: PIG has calved
« on: July 31, 2015, 04:20:39 PM »
Stupid question: where exactly is the collapse in the animation? Am I being blind, or maybe it is cut off at the bottom? I don't know much about the PIG, but I am quite confused here.

BTW that huge crack is so impressive.

The rapid lengthening and widening of various cracks is itself part of the collapse process that ultimately result in the ice breaking off. I believe that is what is being referred to.

I believe that you are referring to the NW corner that nudged forward;

Yes, wrong hemisphere :)

Arctic sea ice / Re: The 2015 melting season
« on: July 31, 2015, 01:31:10 PM »
Its not just the ice north of CAA that is cracking up and leaving the shores, also some of the most resilient ice in between the islands is cracking up and exiting north. This picture is todays modis from Prince Gustav Adolf Sea (to the west) and Peary Channel, both areas which have always seen close to 100% concentration at minimum as far as satellite records go.
I don't know about 100% concentration at minimum, RC, but things cracked up completely back in 2010 and 2011 as well (and probably 2012 too, but I can't remember), with ice moving into the CAA from the CAB.

This year might be earlier though, and it's the way around now, ie ice moving from the CAA to the CAB.

Yes, the ice was pretty meshed up those years (most notably in 2011 I think), but it never left the building, not according to Uni-Bremen maps at least. I'm not sure if those channels will clear up this year either, but the chances are increasing. Note that the narrower channel in the bottom of your 2010 animation, Sverdrup Channel, has been partly or virtually ice free on several previous occasions.

As for the ice in Beaufort, I think everything south of 75N is toast. An ice pack suffering from such low concentration this far south in July simply cannot survive, not unless the import of ice from CAB reaches absurd levels. Just because the ice is stubborn MYI doesn't mean it is immortal.

Arctic sea ice / Re: The 2015 melting season
« on: July 31, 2015, 12:58:33 AM »
Its not just the ice north of CAA that is cracking up and leaving the shores, also some of the most resilient ice in between the islands is cracking up and exiting north. This picture is todays modis from Prince Gustav Adolf Sea (to the west) and Peary Channel, both areas which have always seen close to 100% concentration at minimum as far as satellite records go.

Lou, good post.

Antarctica / Re: PIG has calved
« on: July 30, 2015, 11:58:01 PM »
Spectacular. It looks like the SE corner got a sizable forward nudge as well, but failed to snap. I'm looking forward to a closer inspection of the central crack, and your further analysis of course.

Arctic sea ice / Re: What the Buoys are telling
« on: July 30, 2015, 01:48:54 AM »
Mayor developments at Obuoy12 as well, there is no doubt that the melt pond discussed earlier is no longer a meltpond, but a crack/lead. Lots of movement and open water popping up everywhere, but no updates in its movie as of yet.

Arctic sea ice / Re: What the Buoys are telling
« on: July 30, 2015, 01:31:02 AM »
It seems someone pulled the plug at Obuoy11, attached below is the most recent pic from today together with the last frame of the Obuoy movie (from 27th July).

Arctic sea ice / Re: The 2015 melting season
« on: July 30, 2015, 01:00:19 AM »
With so much of the remaining ice detached from the main pack, not just in Hudson and Baffin, but also in Laptev, in addition to lots of low concentration areas on the Pacific side and the ESS ice tongue looking unusually vulnerable, the stage should be set for a massive August melt this season. However, it looks like the weather won't be colluding to make a proper August cliff materialize. A weak arctic cyclone is already working its way into the CAB, and although cyclone plus low concentration ice have resulted in flash melting and area/extent drops in the past (2011 and 2012 most notably), it doesn't look like this one will have the power to do real damage with its wind and wave action. Cooler temps and a wind pattern that doesn't favour compaction seems to be what this cyclone dominated pattern will bring during the coming week, but I will put quite some uncertainty range on my predictions this time, it may be I'm underestimating the destructive abilities even a WAC (only about 1000 hPa in minimum pressure) can have on a weakened pack.

All in all I concur with Chris that it may be time to write 2012 of the block, but with the underlying conditions and continued heat on CAA, an epic 10-14 day stall simmilar to those from 2013 and 2014 also seems to be out of the question.

Arctic sea ice / Re: 2015 sea ice area and extent data
« on: July 25, 2015, 05:41:12 PM »
Days like this makes such a difference. 2014 is already firmly distanced and 2013 starts going uphill from here. The chance of 2015 finishing above those years has now reached statistically insignificant, as far as I can see, that goes for 2009 as well.

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