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Messages - petm

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Arctic sea ice / Re: The 2019 melting season
« on: September 09, 2019, 03:14:10 PM »
Problem solved! I will be posting my Nullschool graphics here from now on. Feel free to post your own!,2905.0.html

Arctic sea ice / Re: The 2019 melting season
« on: September 08, 2019, 03:00:03 PM »

Arctic sea ice / Re: The 2019 melting season
« on: September 04, 2019, 09:40:55 PM »
I've been watching Lingling and Dorian recently, and I'm interested that they both undergo extratropical transition and integrate their momentum into the jet stream around the same time:

Dorian and Lingling are the symmetrically opposite 968mb lows here. Their angular momentum seems to enhance a dipole pattern, and the timing of their momentum transfer will be critical to how it sets up here. Regardless of the exact configuration, it looks like this will split the initiating tropospheric polar vortex into two lobes and allow a major heat/moisture intrusion from the Pacific

As we enter peak hurricane season, it's important to remember that one of the major heat engines that moves heat from equator to pole are tropical cyclones, so watching their activity will be critical to see how the freezing season initiates (or fails to)

This to me indicates that the melting season is not over yet and way may see losses for the next two weeks. I would be stunned if the AO does not go negative again in the next two weeks, but then again I'm just a naive observer and not a pro meteorologist.

Edit: And after looking at this month's PIOMAS, I really wonder if this will push the Sept 15 update into first place.

Arctic sea ice / Re: The 2019 melting season
« on: August 27, 2019, 11:07:09 PM »
A nice image directly available from Worldview
Current SSMIS (NSIDC) concentration superimposed to NASA blue marble Earth with Bathymetry.

Arctic sea ice / Re: The 2019 melting season
« on: August 25, 2019, 02:53:34 PM »
I hate to say this, but this is the main thread, and its quality has deteriorated a lot this year. We used to have fewer posters with relevant stuff, most often supported by data/graphs; but now we have lots of OT and random musings and (seemingly not very knowledgable) people who post many times a day lengthy posts without much (if any) substance or new, relevant information. I used to read every post on the melting/freezing threads because I could learn from them, but nowadays I skip most because they are more or less worthless. If I were the moderator I would ask everyone if possible to do short posts, only with real, significant data and concise analysis and let's do the philosophizning on other threads.
I hope (wish) the freezing season thread would be different...

Arctic sea ice / Re: The 2019 melting season
« on: August 23, 2019, 11:19:59 PM »
I also hope this is not too big at ~5MB. Unihamburg amsr2-uhh, mar21-aug22, no overlay.
The two persistent, probably grounded, ice areas from my previous post are visible in the ess for most of this animation.

Policy and solutions / Re: Nuclear Power
« on: August 11, 2019, 07:09:14 AM »
Like that's going to make the radiation go bye-bye.
It will prevent them from multiplying though. ???

That high IQ must not be passed on...
Idiocracy was a not fiction!

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

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

Arctic sea ice / Re: The 2019 melting season
« on: July 29, 2019, 01:59:41 PM »

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

Arctic sea ice / Re: The 2019 melting season
« on: July 27, 2019, 01:13:07 PM »
I'll need a few days to get up to speed. But given that this is probably the only thread that is worth reading on the Internet, I would kindly ask everyone to stay as much on-topic as possible and/or keep it short.

Edit: Getting up to speed a bit already today, and just two words for now: Lord Almighty...

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

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

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

Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: July 14, 2019, 08:05:25 PM »
The IPCC does one hugely good thing - confirm with an extraordinarily high consensus that climate disruption is real, that it is entirely caused by man and that it will devastate the environment, civilization, humanity and more.

The IPCC though also does a hugely bad thing. It repeatedly and systematically understates the severity of the problem, the severity of the consequences, the incredible speed at which the changes are occurring, the impossibly great difficulties that we will encounter in trying to keep the change to less than 2 degrees C, the incredibly great difficulty we will have in limiting the change to 3 C, the unimaginably horrible impacts a 3 C increase will have, and more. It is vital to note that the errors the IPCC makes in these regards are caused by politicians and financial interests aided by those who refuse to believe that man could possibly cause such impacts, or worse that the local personal impacts that change would have are more important than the devestation of the earth. It is also vital to note that these errors are intentional and that they all go in the same direction - understating both the severity of the problem, and the incredible speed at which the change is actually occurring.

All of that is shameful and disgusting. The iPCC’s failure as great as the failure of our leaders doom everyone and most species on the earth.

Before there can be any possibility of a meaningful response to climate disruption, we must first be honest about the effects. Only then can we be honest about what is needed to do anything about it, and to assess realistically how much we can do. But doing that means admitting massive failure and the future premature death and suffering of billions of people - and that is if we do succeed. That answer is too horrible for the leaders to even entertain. Failing to take those actions assures those harms and much worse. Somehow though they seem to wrongly believe that if they stick their heads in the ground like the proverbial ostrich, that either the problems won’t come to pass, or that they won’t personally be blamed.

And that leads to my last point. The scientists are particularly to blame for couching the outcome as risks. They seem not to understand or not to want to understand that the people they are reporting to utterly and completely fail to understand that these are certainties of massive destruction, and only uncertainties in how fast that will occur. Risks in this context are not gambles as to whether certain outcomes will occur, but rather how horribly severe they will be or how fast they will arrive.

The outcome is certain catastrophe on an unprecedented scale. And that will happen if we mobilize every capability we have, as fast as we physically can, AND destroy civilization as we know it in the process. Should we fail to do that the outcomes are vastly worse.


Arctic sea ice / Re: The 2019 melting season
« on: July 11, 2019, 01:48:25 PM »
worldview terra modis overlayed with unihamburg amsr2-uhh at 35% transparency, may1-jul10. amsr2 100% concentration has been set to transparent to allow worldview features to show through. There is some misalignment in floe movement, probably due to images formed at different hours during the day. This method helps to continue to see ice movement 'through the clouds'
Large format to show detail, best viewed full screen. (double click)
Both sets of images have small contrast adjustment.
edit: Much of the 'blueing' is from the amsr2 layer, indicating lower concentration ice, slightly darker due to the contrast adjustment
added amsr2-uhh, jul10 for clarification

My best achievement on this forum ever was the email that I, Mr. nobody, wrote Dr. Zhang in 2017, explaining that PIOMAS numbers were eagerly awaited by all, and perhaps they could release the data twice a month. He wrote back sure, they'll try to do a mid-month update. And ever since, they did. I guess no one ever thought to ask...

Arctic sea ice / Re: The 2019 melting season
« on: July 05, 2019, 05:02:08 PM »
I'm afraid a July cooldown is too late to save the ice. Apparently the amount of solar radiation reflected from the Arctic in June is almost a decisive determination of the final September extent (r = 0.91).

Arctic sea ice / Re: The 2019 melting season
« on: July 02, 2019, 04:03:41 AM »
Do you have some useful facts or data to bring to the discussion?

Yeah, I do so almost every day.

I meant the current discussion about how much dispersed ice there is at the moment.  Seems the answer is no

Do you?

I think the fact that the ice is currently less dispersed than 2012 is a useful fact.

It isn't a fact and it isn't useful as an indicator of the rest of the melting season. Early high melt pond extent has been shown in the scientific literature to be a good indicator of a low September extent. As far as I know, there's no literature showing dispersion is. If you can cite the literature, do it now. Otherwise, STFU.

Arctic sea ice / Re: The 2019 melting season
« on: July 02, 2019, 12:51:36 AM »
I hope no one will brand you a troll for your post, there is nothing wrong with bringing a bit of balance to this thread and what you state is true.

Balancing what exactly? The situation is looking very bad, right now. This may change in coming weeks, but right now, the situation looks very bad. Why would that need to be balanced? Practically nobody is saying that 2019 is guaranteed to break records, come September. All we know right now is that it is possible that 2019 breaks records. If you want to balance that, you have to say: It's impossible that 2019 will break records.

If that's the kind of balance you are looking for, you need to compliment weatherdude88.

I agree that it is good to compare 2019 to 2012, especially if things keep going the way they are. But Michael isn't really saying anything, is he? He's just implying something along the lines of 'it's not so bad'. It has nothing to do with balance.

Arctic sea ice / Re: The 2019 melting season
« on: July 01, 2019, 10:13:58 PM »
WD88 is trolling.  Best reply for any WD88 post is no reply.  Ignore him.  WD88 is dead to me.

just thought the same, we should not behave like a bee-hive that was slightly disturbed by a monkey running over the top.

Arctic sea ice / Re: The 2019 melting season
« on: June 22, 2019, 08:56:03 PM »
Lena Delta, 02.06. to 22.06 via Sentinel.

(click to play)

Arctic sea ice / Re: The 2019 melting season
« on: June 22, 2019, 08:10:48 PM »
ascat with unihamburg amsr2uhh overlaid at 70% transparency and 100% ice (white) set to transparent, jun1-21.
Quite a mobile pack with a swift, probably temporary, change of direction in ice heading for fram export over the last two days. The caa-cab crack has snapped shut, maybe also temporarily.
used gimp optimisation to reduce size from 6.2 to 3.8MB. Gimp deoptimise can be used to restore individual frames

Arctic sea ice / Re: The 2019 melting season
« on: June 19, 2019, 02:32:36 AM »
Doesn’t matter how long anyone has been around, and I’ve been here way before him.

Hauber is a concern troll climate risk denier. He adds nothing to any discussion except to muddy the waters, and mislead others. Do not confuse his word salads and copy-pastes to intelligence. He is an expert troll that will always leave you wondering if he is discussing in bad faith. He is immune to evidence.

Regardless of what climate risk is being discussed, Hauber reflexively defends the most conservative position possible without appearing a complete climate denier.

On extent flattening, part of the issue is that ice loss in Kara has flattened due to low pressure keeping this area cool.  This area is often freefalling at this time of year.  Note also that area is not dropping fast because of a genuine reduction in area, but because of melt ponding.  I think it is more the fast drop in area rather than the slow drop in extent that is false.  Although the drop in area does reflect rapid surface melting, so while false in some sense, it is still significant and real loss of ice is likely to follow.

 This error happens every year so you are still comparing apples to apples and can even interpolate extra data from this. Stick around for this forum for a few years please :)
Say that to yourself, that guy has been around forever.

Arctic sea ice / Re: The 2019 melting season
« on: June 06, 2019, 03:25:11 PM »
Take a look at 6Z GFS.




Arctic sea ice / Re: The 2019 melting season
« on: June 01, 2019, 12:41:07 AM »
ECMWF forecast shows a continuation of that huge high pressure area for at least three more days, but then things get more interesting with lows trying to butt in.

How we already know 2019 will be a big melt year for Greenland

And high pressure over Greenland for 7 days…
Even that it is not as medium term (2019 melting season) as the forecast, it adds on.

Arctic sea ice / Re: The 2019 melting season
« on: May 29, 2019, 11:35:51 AM »
Hi everyone
first time poster and attentive reader of the forum  :)

Maybe that helps dissolve some of the confussion about the weather in barrow:

Developers Corner / Re: Test space
« on: May 23, 2019, 09:47:12 PM »
Testing the waters again on all-ImageJ Ascat mp4. Good labels can be made and positioned as desired if the files are renamed properly before loading. Duplicating the stack, cutting and filling to text box size, then enlarging canvas to fit final size of the data stack, using 'paste control' set to 'zero fill' which is ImageJ's way of setting pure black as alpha transparency.

I also compared 'equalize' to manual brightness and adaptive contrast as a quick and easy contrast adjustment. If an Ascat land mask is loaded, these tools have a better histogram to work with that does not include noisy weather patterns over open water. The land mask is helpful in defining crop boundaries. If it is included in the stack of Ascats, it will be cropped just like them and can be used at any time up to mp4 production.

The specific task here is optimally depicting movement of the last holdout ice between the North Pole and central CAA (which has poor inherent contrast). Normally it just sits there but over the last 172 days a great unprecedented swath of ice has steadily moved from islands off central Siberia across the pole nearly to and out the Fram. The older ice is been squashed up against the Canadian islands, with some pushed towards the Beaufort, some forced through Nares, some possibly to the Barents, with most going down the Fram. The Ascats are again spaced at five days to reduce file size of product.

Despite wx predictions to the contrary, this pattern has continued through May 22nd. This, if it continues another month, will lead to shocking developments by fall so I am inclined to bury the mp4 here in development where fewer will get unduly alarmed ahead of events. Even with a so-so melt season, there would be very little surface area, volume, or multi-year ice left going into September. However we have seen other years like 2012 where weather simply shifted and the melt season trajectory changed to something less damaging.

It's never been clear what would hold the old ice against the Canadian islands if the outer ice pack is not there to exert pressure; wind patterns could well change with more open water, this ice might drift off, be broken up by waves, with its remnants disappearing.

Some movements of continuously recognizable features are shown in the static image. It is better to circle reference areas than to use vectors of point displacements because of rotation and deformation. The dark ice is mostly first year and so the displacement of its front is feasible to measure. For scale, it is 1050 km from Longyearben, Svalbard to the North Pole.

The attached high precision land mask is from AMSR2UHH. It fits very accurately over the 1170 x 1170 Ascats.

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