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Messages - Thawing Thunder

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Arctic sea ice / Re: The 2017 melting season
« on: August 27, 2017, 01:40:16 PM »
Very nice and interesting. Thank you GD2!

Arctic sea ice / Re: The 2017 melting season
« on: August 15, 2017, 03:34:00 AM »
Watching closely yet reserving judgment.  I recall quite a prolonged warm spell across the CAA a few years back, which I thought would cause a dramatically early opening of the NWP.  In the event, it was only a little early (end July iirc).  It takes a lot of heat to melt all that ice.
The difference could be, that this time we are in August and the straight has already received moths of energy.

as to the NWP, due to last years import of more than usual MYI chuncks it will take even more to clear it, keyword "garlic press".
Interesting point. Could be true.

Arctic sea ice / Re: The 2017 melting season
« on: August 14, 2017, 12:58:53 PM »
I think the CAA will indeed start to run the Garlic Press soon.  But its not flowing yet.

With all that heat from Canada entering the Canadian Archipelago a lot will start to move there. We could even see an ice free Perry Channel within a week. After that 2017 will certainly look much more similar to 2012 on the Pacific side.

Arctic sea ice / Re: The 2017 melting season
« on: August 11, 2017, 02:00:10 PM »
Not that we might get a significant storm. That has not been the way of this melting season.

Looks more like the continuous battering of smaller storms – which, summing them up, could have the same effect.

Arctic sea ice / Re: The 2017 melting season
« on: August 11, 2017, 12:02:21 AM »
Then it looks like it's just a part of the mayhem.

All that area around that big polynya is pushed into the Laptev Sea, opening up the Laptev bite deeply toward exactly that polynya (and maybe even the opposite way toward the Beaufort Sea). Also the whole atlantic side is being pushed into the open waters between the islands. So there isn't any compaction and area & extent won't drop as fast as they should. But I think despite of that it's not a positive sign what's happening there. Probably we can consider us very happy that all this didn't start ten days or a week earlier.

Arctic sea ice / Re: The 2017 melting season
« on: August 04, 2017, 12:17:57 PM »
... the satellite picture shows you only the 2d-version of the ice, so it is hard to impossible to get that from the satellite image....
As much as a satellite can't detect 3D, it can detect effects in two consecutive days that can give us a very good idea of the average thickness of the ice. Indeed, the concentration derived from the AMSR2 instrumentation has just shown a huge phenomenon of "flash melting" one day and "unflashing" on the next, inside the marked oval. What this has indicated in other occasions is that the affected area is very close to the total disappearance. Such an advanced melting ice stage is not compatible with 2-3 meters average thickness.

So, the DMI map might show the ice in general a bit thicker, than it actually is, but the distribution of the volume in the map matches IMO in most areas quiet well with the satellite image.

I think the latter comment opens a possible approach between these two points of view: GENERALLY speaking, DMI is correct, showing the ice a bit too thick. On the other hand, you can definitely pic local failures.

Arctic sea ice / Re: Home brew AMSR2 extent & area calculation
« on: August 04, 2017, 11:58:56 AM »
That bounce back looks to me in part like inaccurate measurement due to clouds.

Arctic sea ice / Re: The 2017 melting season
« on: August 03, 2017, 08:19:27 PM »
I compared the DMI thickness map to the Hamburg concentration map. For me they just don't fit.  :o (edit: for better visualization I quit the violet 25cm-edge)

Arctic sea ice / Re: The 2017 melting season
« on: August 03, 2017, 04:05:14 PM »
Given how fractured and mobile the ice is, it may just be better to simply animate as the blinking on and off actually captures the state of the ice.

The perfect solution would be a software with pixel tracking. No double count of pixels in still pictures anymore. That could provide a nearly lossless composite, even over several more days.

Arctic sea ice / Re: The 2017 melting season
« on: August 03, 2017, 03:52:45 PM »
Is it just me of is everything outside the triangle canada ~135th longitude and 15th longitude looking to go poof in any moment?

I think so, too. But it's August. If all that had started just a week earlier, I would have called "doom!". But it didn't. let's wait and see.

Arctic sea ice / Re: The 2017 melting season
« on: August 03, 2017, 01:31:06 PM »
Sorry, if I'm interrupting the current discussion. Just posting an animation of the last two weeks with some slowmotion. In my opinion now you can see very well, what are clouds and what is SI. If the trend we see continues, the next two weeks could definitely wreck the ice.

Arctic sea ice / Re: The 2017 melting season
« on: August 03, 2017, 12:38:51 PM »
Not too much work left now. Generating the 3-day (or n-day) minimum maps is already automated. I wrote a program to do it -- that's how I made these maps.

I envy you computer guys!

All I need to do now is generate one for each day (one more for-loop should do it) and then figure out how to join them together into a movie, which is easy I guess.

Make a gif. You can make it online, there are free platforms and it's very easy. Or import the images in your favorite editing software for longer an higher resolution results. If your are creating a loop: Please let the last image stand a while longer. That provides orientation in a loop. Otherwise there is a continuous swirl that causes nausea ;-)

Arctic sea ice / Re: The 2017 melting season
« on: August 03, 2017, 11:53:34 AM »
...but at the same time introducing other false values, because every ice movement will decrease concentration in your image, regardless of the real situation.

As I wrote several times, I'm conscious of that effect. But without pixel peeping I think these images contribute something useful.

... I am not convinced, that this 3-day-composite, that amplifies just low concentration pixels, is anywhere nearer at reality, than the original images in the first place.

They are certainly flawed – as are even highly scientifically manufactured images. But it shows a more overall picture that you otherwise would not obtain. As I could observe last year and this year, they are useful to see where the ice is going. Of course, you have to take these images with a grain of salt – as you do with every graph here, I suppose.

... because I want to make movies of them (which I think may be even more revealing) ...

With a running three-days composite? THAT IS A LOT OF WORK!!! But the result would be utterly pleasant, and it would somehow mask away the distortions caused by drift in the continuous over all movement!

Arctic sea ice / Re: The 2017 melting season
« on: August 03, 2017, 10:58:10 AM »
On a similar note, I have noticed that occasionally someone posts a merged image of the Bremen (I think?) visual colour map, where the darkest pixel has been chosen over several days to help remove cloud effects.

Hello GD2, I think that was me. I did exactly that last year, first manually and then, in the later versions, with the color picker in Photoshop (not the darkest pixels though, but the brighter green, yellow and red ones). This year I changed to the Hamburg map, which I feel has a stronger visual impact (especially if you push the contrast à la Wipneus), I posted my last result yesterday as a gif-animation. I think it's helpful if you want tho get a view of the whole picture, between three images lay just 48 hours, so in most weather conditions the drift is not so strong, and clouds move faster anyway. Great that you are contributing something similar, a single image says more than a thousand words!

Arctic sea ice / Re: The 2017 melting season
« on: August 02, 2017, 10:01:52 AM »
Animation of the last "worst case 48 hours composite". You see how the last three Hamburg images (30th, 31st, 01st) are merged together, thereby you can observe the limits of the method (distortion by drift, double count of dark pixels). But altogether it gives an additional insight, I think.

Arctic sea ice / Re: Year-round ice-free Arctic
« on: August 02, 2017, 08:33:51 AM »
I have limited understanding of the dynamics, but that sounds reasonable. Ocean currents are limited regarding the Arctic, because ist's closely surrounded by land – though on the other hand the Golf current is a heavy weight.

And there are the jet streams. With their possible disappearing, warm air will reach much higher, even in winter, even in Bering. We had some extraordinary events of warm winter air at the north pole even with the jet streams still existing.

There are many variables in the future that could lead to a warmer arctic. But even a cold rush could be in the cards for some decades. Still the oceans accumulate most of the heat, we'll only see the whole picture when they start to "overflow".

Arctic sea ice / Re: Arctic Image of the Day
« on: August 02, 2017, 01:12:45 AM »
... while over the Kara Sea is whirling a little storm.

Arctic sea ice / Re: Year-round ice-free Arctic
« on: August 02, 2017, 12:28:56 AM »
Yes, upon a time frame of 20 - 50 years I do agree. Even on 5 - 50 years, while I would not bet the farm on the nearest possible date of a state change (I agree on that term, too, as far as it implies a sudden change).

But 20 years, yes. Inertia is a big factor for us frogs in the kettle (and we are many, considering the population overshoot).

The only solution that is on its way to solve all this at least long term, IMO is solar energy. We'll see if this will save some kind of technological civilization, once humanity has shrunk to say a billion. Hope it will diminish in a controlled and conscious way, though I doubt it very much. By "controlled and conscious" I mean by voluntarily reducing the birthrate and giving the possibility to those who are alive to life their whole lifespan. But I think I'm getting off topic now.

Arctic sea ice / Re: Year-round ice-free Arctic
« on: August 02, 2017, 12:08:25 AM »
DR, to me it seems like a cataclystic singularity, all those events converging in the next years and decades. Peak ice, peak oil, peak humanity, peak brain power, peak species ... you name it.

Thinking about it ... exponential events probably tend to converge in a narrow window because of their limited expansion in time.

So no mysticism involved, just man, maths and the carbon age.

Arctic sea ice / Re: Year-round ice-free Arctic
« on: August 01, 2017, 11:21:44 PM »
I can agree on that there'll be a tipping point after which everything will look different. But when this is going to happen? Who am I to tell you or even make guess. We will probably see it in the rearview mirror and agree then (if we're not totally occupied with survival then, or even worse).

One of the things of the thawing Arctic that attracts me and lets me watch it, is exactly that: You can see a change with your own eyes (though enhanced by satellites) and all within a human timespan (I'm watching this for a decade now, so much has changed!).

Sometimes I doubt this is sane or helping anything. Sometimes It seems to me like a morbid fascination. But here I go. And go on watching ...

Arctic sea ice / Re: The 2017 melting season
« on: August 01, 2017, 11:08:58 PM »
The area north of Laptev is breaking up and thinning big time.

Arctic sea ice / Re: The 2017 melting season
« on: August 01, 2017, 06:43:34 PM »
P.S. Did i say the thing you quoted me saying? I think the honors are not mine.

It was Oren. Sorry, I quit the wrong name in that quote.

Maritime climate.  The Arctic is no longer a desert.

You nailed it so simple, it's eyeopening! When I read it, many details I soaked up on this forum just concentrated into those words. Thank you! (@Tnioli: Yes, it's oversimplifyed, but focuses very helpful on the right issue. At least for me.)

I keep seeing it said that "it gets harder and harder to melt the remaining ice," or words with that meaning, but I cannot remember ever seeing an explanation why that might be so.  Seems to me that just like in a margarita, the last of the ice would go quickest. By then you have run out of cold.

I imagine this refers to the idea that the Arctic is becoming a giant Hudson Bay. That means, ice covered in winter and free in summer. Even with much higher temperatures, there will probably always be freeze in winter, that's why there will probably never exist zero ice all over the year.

But interpreting it only for the melt season, I think your margarita-observation makes totally sense.

Arctic sea ice / Re: The 2017 melting season
« on: August 01, 2017, 05:23:38 PM »
Thank you Oren.  Some people are so caught up in their own conclusions, that they cannot see straight.  As both you and several posters have commented, the changes in both the winter and summer weather may have been a bigger factor than the overall temperature increase.

My conclusion is that you better have a look at the whole picture, especially at volume. And no, there's no danger to start squinting by doing it. Give it a try!

Arctic sea ice / Re: The 2017 melting season
« on: August 01, 2017, 05:05:45 PM »
So since 2007 it has been mostly first-year ice that melts and then refreezes, leading to a more stable pattern.

That's why I called the choice of the timeframe willfully – and sorry, no harshness intended – because it doesn't show the drop of 2007 itself. It really can create the illusion of a flat graph, especially with the "recovery" of 2013/14 outweighing the "exceptional" low of 2012.

And I don't think the destruction of MYI finished back in 2007, it just started. It's rather the year 2016 that hammered the last nail into the coffin. We'll see the next years – or even this one – how all this is going to play out.

Arctic sea ice / Re: The 2017 melting season
« on: August 01, 2017, 02:39:42 PM »
Afterall, the minima has been flat over the past decade.

This is a misinterpretation, based on a quite willfully selection of the timeframe. 2007, 2011, 2016 have become an new normal, but 2012 is just waiting to take that place. There isn't anything such like a flat minima. The Arctic is warming and loosing ice constantly, but just not on a straight downward line.

Arctic sea ice / Re: The 2017 melting season
« on: August 01, 2017, 11:38:56 AM »
And: While in summer the temperature differences are minor, in winter they become really big.

Yeah, looking stormy... current weather (pressure, wind, waves):

Even if that's not a GAC, it hits exactly where we actually find the weakest ice.

Arctic sea ice / Re: The 2017 melting season
« on: July 30, 2017, 09:59:09 PM »
Worst case 72 hours (correction: 3 daily images=48 hours, not: 3 x 24 hours  ::)) composite of thin areas, contrast enhanced. If one supposes that in many cases clouds hinder a correct depiction of the ground, this could be an approximation of what's happening there - though certainly an exaggerated one, please have this in mind.

Arctic sea ice / Re: The 2017 melting season
« on: July 30, 2017, 01:09:25 PM »
I think the hole in the ice north of Laptev Sea has formed now.

Arctic sea ice / Re: The 2017 melting season
« on: July 30, 2017, 03:36:05 AM »
Sorry TT , but the dotted line you are referring to is the 75th parallel .

Uh, yes, quite a difference, thank you BC for correcting this.

Arctic sea ice / Re: The 2017 melting season
« on: July 30, 2017, 12:19:37 AM »
The Slater Projection is similarly optimistic in that locale, and a bit more optimistic elsewhere.

Watch the dotted line: That remnant thick ice you are referring to, is the only one south of the 80th parallel north. It should be much more exposed to melt conditions than the rest. So there's no certainty that this ice prevails.

Arctic sea ice / Re: The 2017 melting season
« on: July 29, 2017, 11:08:07 PM »
Funny, I had drawn a similar outline on the 25th, but just didn't do it as precise.

The less precise the better at this date  ;)

Arctic sea ice / Re: The 2017 melting season
« on: July 29, 2017, 07:18:10 PM »
Hello Shared Humanity. Technically you're certainly right. But a decade of watching such images conditioned my guts in that way: Melt is where the colors shine. Of course that dermatologic blistering of the Atlantic side could spread further into the CA, who knows ...

Arctic sea ice / Re: The 2017 melting season
« on: July 29, 2017, 04:53:02 PM »
and your overlay in places is quite optimistic, i'm sure we won't see the perry channel entrance closed in september or end of august even.

Concerning September you are probably right. I did not go that far as to dare to make an accurate prediction. I just saw that pattern on the actual ice.

What truly gives me to think and to worry is the quite cooler temperatures around Greenland on the Atlantic side in 2017.

Have a read just a bit upwards this thread. FishoutofWater and Hyperion are giving interesting explanations.

Arctic sea ice / Re: The 2017 melting season
« on: July 29, 2017, 03:33:26 PM »
And beforehand the ice starts to look really weak. Only a very central area that is not affected by melt. That storm could be a killshot (not to mention that worrying observation Hyperion and Fish out of Water made - which explains the atlantic melt that at fist sight seems so strange given this year's cooler water in this area).

Arctic sea ice / Re: The 2017 melting season
« on: July 28, 2017, 09:52:18 PM »
this image somehow give a nice outlook how things will probably end up this year, the color scheme is somehow user friendly and easier to interpret than many others.

everyone can easily draw the lines and be impressed, this image somehow implements thickness to extent in a different than the usual way.

I don't know. Ice thickness seems such a wild guess to me, I wouldn't bet anything on any of those graphs. DIM, NAVY ... you name it. Each is so different, some show the Atlantic side thinning, others the Pacific area. I agree that there's a lot of thin ice, and that it's certainly distributed rather towards the edges. But if there's nothing strange going to happen soon, this season is running out of steam for a new record. If the anomalies show up that late like last year, only a cyclone could push the limits. But with each day that goes by, I doubt more that that poof-event I was so convinced of, is really going to take place.

Arctic sea ice / Re: The 2017 melting season
« on: July 28, 2017, 12:19:50 PM »
That thinning spot in the middle of the image, north of the Laptev Sea, already exists over a week now. Just waiting to see open water there.

Arctic sea ice / Re: The 2017 melting season
« on: July 28, 2017, 12:11:26 PM »
From this weather forecast Kara and Barents will import another wagons of ice from CAB. Despite their waters colder than in previous years but it seems warm enough to melt any imported MYI

Probably it's not even MYI, but FYI.

Arctic sea ice / Re: The 2017 melting season
« on: July 27, 2017, 02:00:53 PM »
I was called a denialist.  The theory, to which I posted recent research was called "debunked" and several questions were asked as to why I should even be able to post here.  If you believe that one sardonic comment of mine, followed by a zipped mouth emoticon, is baiting, then I guess I can't say any more.

Sometimes, all this reminds me of Peak Oil: At the "peak" of that theory, there were those fights between peaksters and cornucopians all the way. Then the peak was delayed, mostly by US-fracking and a booming Irak production ("the price") and both sides screamed victory: "I always knew peak oil was a scam!" against "The peak of conventional oil DID HAPPEN back in 2005."

Then, with a diminished audience, a rationalization took place and the best of those brains started to reanalize the situation with new knowledge and information. Suddenly the doomers and cornucopians went away, they couldn't stand the timeframe of the delayed disaster (now probably around 2025).

Same could happen here: The blue ocean WILL happen, but it could easily happen in 2025, too. A lot of time for scientific observation and preparation. Though I don't say it will happen that late. All I want to say is, that since 2007, or at least since 2012, many here are awaiting a doomish scenario taking place very soon. But nature and also mankind have proven that they don't stick to individual desires and expectations.

Arctic sea ice / Re: The 2017 melting season
« on: July 27, 2017, 12:49:34 AM »
I think the positions on this board are closer than it sometimes seems. In this GIF I compare a fictive state of the ice, which I would consider very preoccupying, with the actual Bremen image.

Arctic sea ice / Re: The 2017 melting season
« on: July 26, 2017, 10:33:07 AM »
Things have been kind of quite lately in the Arctic. Really not that bad of a year. Not much momentum, the melt season seeming to just fizzle out. Or is it just being a little sneakier this year.

Funny. I'm planning the same animation, but from exactly the opposite point of view (and therefore I am waiting a couple of days longer). No fizzle out but sneakyness with a bang. I feel the state of the ice is worsening at an accelerated pace and the atlantic side today entered a 2013 lookalike-contest. I know time is running out this season, so maybe we won't see a catastrophic outcome, but it's all far from over.

Arctic sea ice / Re: The 2017 melting season
« on: July 24, 2017, 02:16:07 PM »
Thank you Jim, I'll give it a try!

Arctic sea ice / Re: Home brew AMSR2 extent & area calculation
« on: July 24, 2017, 12:24:41 PM »
The Canadian Ice Service produces a weekly composite image that tries to show as much of the arctic cloud-free in that period of time. The image is generated every wednesday for the preceeding week.

That's great to know! Though this image is lacking resolution. I tried something similar with a part of the Arctic, using world view images. Much more detail. You can see it in the melt thread or on flickr in full resolution:

Arctic sea ice / Re: The 2017 melting season
« on: July 24, 2017, 12:13:47 PM »
Yeah TT that gives a much more approachable view of what we have overall. What pixel size on worldview did you start with? 1km? 5km? Or have you smaller blocks with the full 250m available resolution?
We could start a thread where volunteers  team up with territories assigned, archive frames, and just clip the visible areas out for each tile . Then layer those. and perhaps cheat a little with a bit of clone brushing to fill in the holes.
Its pretty easy with the Lassoo tool and control and shift keys on my oldschool paintshop pro4 to do that. Dunno about others apps.

tried a few of psp tools on it. Only thing I could do that might have brought out a little detail thru the clouds was max the colour saturation and a slight contrast boost.

I started with the images you obtain with the camera function on the world view site, 9328 x 6032 pixels. I tried to upload the result, but it was too big. I did not apply any lasso or stamp or whatsoever. The clouds you can see simply were in those places for a week (But I cleaned up the open water with a brush). One week anyway results in a lot of distortion because of the movement and melt of the ice, though in the central area of the pack it was not so much. If anybody wants to see the full resolution image, I uploaded it to flickr:

With regard to your suggestion to organize this task in a group – that would require a lot of organization and discipline, maybe too much. Single persons like Wipneus maintain their very much appreciated rhythm here of daily contributions. But a group of people? And it's not easily done. That image took me hours and even with some routine it will require a lot of time. Please understand me, I'm sceptic but not against your idea.

Arctic sea ice / Re: The 2017 melting season
« on: July 24, 2017, 01:23:29 AM »
I bit the bullet, stacked one week of images from the eastern Arctic and removed the clouds manually (took hours). The images I used go from the 17th to the 23rd, latest image on top to avoid distortion by drift and melt as much as possible. Some contrast enhancement is applied.

Arctic sea ice / Re: The 2017 melting season
« on: July 23, 2017, 09:03:34 PM »
2017 has comparable extent and comparable volume to 2012, and is a few years after 2012.  2007 contended with thicker stronger ice than 2012 did.  If you normalize for the quality of the ice, a one in five event does not seem that unlikely.

We are in that spot where all the low years converge.  The divergence has been in the 2nd week in August. ...  The ice is not in good shape. ... We had a low maximum this year. 2012 had a relatively high one, so the decrease in area and extent are inherently different.

I think there is more peripheral ice (eg. Baffin Bay, Greenland Sea, Novaya Zemlya) than many previous years, and that will disappear, causing a larger than usual drop in extent, since it is all adding to an illusory extent right now. ...

Just posting three quotes that sum up my own point of view very well.

Arctic sea ice / Re: The 2017 melting season
« on: July 23, 2017, 04:33:10 PM »
If I understand your table correctly, the required extent loss is almost the same as actually happened in 2012 from now til minimum. Extraordinary indeed, but still possible, especially as volume is tracking 2012 as well.

It is tracking 2012 volume AND has very thin ice in areas especially exposed to melt like the Beaufort Sea. I'm not sure that anything extraordinary has to happen to equal 2012. I still expect the CA to show bigger open areas at the beginning of August and that those holes will push extent and area toward a new record. I know, it's all speculation and depends on something we don't really see: Bottom melt.

Arctic sea ice / Re: Home brew AMSR2 extent & area calculation
« on: July 21, 2017, 08:16:38 PM »
I like what you are attempting.  I would 'wish', somehow, that the larger floes (maybe 10-20 percent of total area, depending on size criteria) could be made entirely ice-white.  Right now, they are all melty-black speckled, some approaching half-black.  I think this exaggerates how advanced the melt is.

Yes, this is a very valuable contribution. But Hyperion should not push the contrast too hard. I have a lot of experience with Photoshop and alike: These images after all are pretty low resolution 8bit – there's a point of no return where you loose more than you gain (which, by the way, somehow fits our topic here  :o).

Arctic sea ice / Re: The 2017 melting season
« on: July 21, 2017, 07:40:14 PM »
2013 was very cold, relatively speaking, both air and sea surface temperature. When it comes to sea level pressure, 2017 is somewhat similar, though I'd venture to say that 2013 was more cyclonic (I'd have to look it up to be sure). But temperature is the big difference between the two.

Yes, I remember now the drama of 2013 which finally ended up as a "rebound" year. Very interesting year. So ist this one.

Arctic sea ice / Re: The 2017 melting season
« on: July 21, 2017, 12:52:19 PM »
But for now, this year isn't looking anything like 2016, 2015, or even 2013. Here's a comparison using Uni Hamburg AMSR2 sea ice concentration maps:

I agree with 2015 and 2016, not so much with 2013, at least not on the base of a single image. The atlantic side this year already started to show polynya - and is therefore at the brink of open holes.

But what strikes me most, and IMO isn't considered as much as it deserves, is the size of the central ice pack. Despite of its coherent appearance, that means still without holes, the overall size (let's call it extent at eyesight) is much smaller than in the previous years. I would guess and advantage of about one week to ten days. And I also beliefe that big areas of that ice are thinning away at an unprecedented pace and will surprise us soon.

A couple of comments above Tigertown posted today's image of the Arctic from Uni Hamburg which shows the ice is developing into the state and direction I am expecting for the next weeks, a trend that started a couple of days ago.

Arctic sea ice / Re: Home brew AMSR2 extent & area calculation
« on: July 21, 2017, 08:37:50 AM »
Put ice in a mixer: After the first second or so you'll have big chunks, a real broken up mess. Like 2016. Start the mixer again, and after a while you'll get something smooth an seemingly much more coherent. Like 2017. That's where you make Daiquiri from. But the ice is not really in better shape than the chunky pieces, though it certainly has a higher compactness and a better look. I think we are in Daiquiri times and there's still a lot to happen this season.

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