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Messages - Freegrass

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1
Arctic sea ice / Re: The 2019/2020 freezing season
« on: October 04, 2019, 09:47:06 AM »
  As I'm up in court for sentencing tomorrow for giving free grass to a number of people with serious medical needs I may not be here for the next 6 months (or even 7 years) .. I am considered a 'persistent offender' having 8 previous convictions for 36 similar offences . These will be taken into account .
       just b.c. :)

Wow, that sucks. Good luck, I hope you have a good judge in a good mood.

Meanwhile, September 2019 didn't break any regional records, but was stil second warmest on record overall, and the third time after 2006 and 2016 to be above freezing (in my spreadsheet):

2
Arctic sea ice / Re: The 2019/2020 freezing season
« on: October 04, 2019, 07:04:29 AM »
So sorry to hear that BC. FreeGrass doesn't mean giving away grass for free. It's just my way of saying "Free The Weed". Freedom for cannabis users. I've been fighting that fight for almost 40 years now, and if I were you, I would tell your lawyer to bring up the "Declaration of Principles on Equality". My conclusion after 40 years is that (illegal) drug users are being discriminated against. Why are deadly hard drugs like alcohol and cigarettes legal, and other, less harmful drugs, illegal? Why doesn't society like me? Because I use a much safer drug than alcohol? You've seen what alcohol can do to me... So the current drug laws are in conflict with the anti-discrimination laws. That's my end conclusion on the drugs debate...

[Sorry, totally off topic, but interesting nonetheless.]

Freegrass, I don't know where you live, but in the U.S. cannabis is slowly being legalized in more and more states. Most of the Dem candidates seem to be for federal legalization. More and more conservatives are getting on board too as more data is produced showing the benefits of weed compared to many legal drugs that are more harmful. There are cannabis conferences popping up all over the place, involving merchants and lawyers. Hemp-derived CBD is essentially legal nationwide since 2018 but regulatory schemes are still in doubt. The FDA may screw it all up as they often do.

Anyway, I don't think your fight has been in vain. Attitudes toward weed have liberalized radically over the past few years.

Although I have never been a pot user, I became interested in the commercial aspects of it because a fried of mine came up with an interesting product (combo drug). Also, I developed a terrible pain in my shoulder and neck about a year ago and found great relief using a topical salve I purchased in one of the states that legalized pot. I currently live in a state that doesn't yet permit the sale of cannabis, only the sale of hemp CBD. I therefore developed my own very effective topical pain salve that contains CBD (and presumably no more than the legal limit of 0.3% THC) and other components. It has miraculously cured my pain better than the stuff I bought before.

Anyway, this is no "snow job" so hopefully on topic!

3
Arctic sea ice / Re: The 2019/2020 freezing season
« on: October 03, 2019, 04:54:54 PM »
What if the Barents is warming because the slowdown of the AMOC - and probably other factors - causes it to rise more to the surface - hence the hotspot west of Svalbard -  and thus instead of the hot Atlantic water sinking to the deepest parts of the Arctic, it stays high, and heats up the Barents?

This is an incredibly persistent misconception. The warm Atlantic currents are surface currents. They do not "rise more to the surface" since that's where they are to begin with.

And hot (or warm) water does not sink unless external factors make them sink, of which there are basically two that can operate in tandem:

1) The hot (warm) water cools down on the surface, and due to it's high salt content it ends up sinking.
2) The hot (warm) current meats freshwater and sinks in spite of being warmer, since the salt content makes it heavier.

But then comes the "AMOC is slowing down" hypothesis which is based on increased amounts of fresh water (meltwater from Greenland) diluting the hot (warm) Atlantic surface water and stopping it from sinking!

Since the sinking of the (cooled-down) surface current is thought to be a large driver behind the AMOC (perhaps constituting 1/3 of the total), when less cooled-down water sinks due to lower salinity, the AMOC loses power and starts slowing down.
Meanwhile over 90% of the increased energy trapped by rising CO2 ppm is going into the oceans, and the North Atlantic is getting its fair share.
The Air temperature in the Arctic is warming at twice the world average.
The Albedo Warming Potential of seas like the Barents which are so much more ice-free much earlier in the melting season is rising quickly - (See the "May June July" line in the graph I attach again).

So my speculation that belongs to me is that a slowing AMOC might slow down the Atlantification of the Barents - (which then advances into the Kara, then the Laptev?) but cannot stop it. Timing - I have neither the maths nor the bank of supercomputers. Got a few hundred million bucks to spare?
_______________________________________-
ps: The ESS is being attacked from both sides - earlier melt in Laptev & Chukchi, and from the south - a warming Siberia.

4
Arctic sea ice / Re: The 2019/2020 freezing season
« on: October 03, 2019, 03:12:18 PM »
Free(grr)ass   .. gaining more knowledge can be done by reading the past .. your lack of knowledge could be overcome readily . AMOC and Svalbard's ghost hotspot have been frequent topics of discussion .
nothing new has been added to the debate in several years .. just new posters repeating .
 I usually avoid this thread now .. after multiple visits daily since 2013  . Thank you ! As you well know I cannot afford your continual delivery of self-loading mp4's .

 Lorenzo has dropped by (N. Ireland ) .. wind and rain steadily increasing . A lot of L's energy is heading toward the Arctic , mostly via Greenland . Temps are forecast to briefly reach >0'C at the pole in a few days.
  Those last few days record low ice days from  2007 look like being replaced by 2019 later this month .
b.c.
 


Most regrettable you feel like that, I always welcome being able to read contributions that foster my own understanding and I have always felt that this forum has a brilliant tolerance to those less knowledgeable.

5
Arctic sea ice / Re: The 2019/2020 freezing season
« on: October 03, 2019, 01:53:18 PM »
Last 24h + Five day Forecast
October 2 - 8

Wind + Temp @ Surface + Total Cloud Water
The colder temperatures exactly where the ice pack is. It's about a week until the inner basin should start to refreeze very quickly. But we'll see how it will go this year since it was the highest AWP in summer this year

6
Arctic sea ice / Re: The 2019/2020 freezing season
« on: October 02, 2019, 08:29:41 PM »
I wasnt aware (until today) that the old Norwegian Met Ice Service and charts, previously available at http://polarview.met.no/ (url no longer works) are now available in a new revamped website at:

https://cryo.met.no/en

I've just perused through this site and it is a treasure trove of charts and data. ASIF members, bookmark it ! 

Maybe mods would like to add it to the ASIG section ?

Here is a sample of some of the images available on the website  (Mosaic view of Sentinel 1 images) :

https://cryo.met.no/sites/cryo.met.no/files/latest/SAR-mosaic-latest.png

7
Arctic sea ice / Re: MOSAiC news
« on: October 02, 2019, 07:15:57 PM »
Slideshow with the latest images.

8
Arctic sea ice / Re: The 2019/2020 freezing season
« on: October 02, 2019, 05:59:05 PM »
I wonder if it has anything to do with the AMOC.
That's what I always thought. I thought that maybe the AMOC changed its path a little somehow, and is now bumping into Svalbard, causing it to rise to the surface, heating it up.

A valid hypothesis!

9
Arctic sea ice / Re: The 2019/2020 freezing season
« on: October 02, 2019, 06:45:38 AM »
7d hindcast mean...

10
Arctic sea ice / Re: The 2019/2020 freezing season
« on: October 02, 2019, 12:40:30 AM »
I wonder if the slowdown of the Gulfstream has something to do with the lack of ice loss on that side...

I don't think so in a currently significant manner.

Let's not forget that even though there may be a slow down, the waters are warmer i general, hence one would have to carefully calculate which effect is overruling the other.

Further as far as i can observe, the Atlantic warm waters flow ever farther east along the Russian coast. I think it has mostly to do with prevailing winds/currents and with the more mobile ice conditions.

In spring and during summer we could very well observe the thicker than usual ice north of the islands and since the north of the islands are in "Lee" current-wise it got kind of stuck there.

Of course what remains is to further carefully watch the coming seasons to see whether a pattern
is developing or not. Nothing is certain these day (or ever)


12
Arctic sea ice / Re: The 2019/2020 freezing season
« on: September 28, 2019, 08:24:28 AM »
The wind has some say in this.

13
Arctic sea ice / Re: The 2019/2020 freezing season
« on: September 27, 2019, 08:24:44 PM »

More snow = more sunlight reflected = cooling. 

Not cooling but less or later warming, that's not the same.

Cooling would happen if temps would generally be lower than before but as they are generally higher (AGW!) we have reduced/later/ warming over snow covered area than over not snow covered area.

The biggest problem with more snow is that it makes it harder for the permafrost to refreeze, and that would lead to warmer landmass during summer, and more methane in the air.

Early snow traps heat in the ground and in the ice. Instead of the surface being able to radiate heat directly to and through the atmosphere (say - 40°C) it has to conduct the heat through all those nice air pockets in the snow. On sea ice it would effectively lower the number of FDDs

Early snow = slows down heat loss (insulator)
Late snow = slows down heat gain (albedo, specific heat of melt to overcome before ice and ground heat up, insulator)

Of course and model would depend on the latitude and time of year


14
Arctic sea ice / Re: The 2019/2020 freezing season
« on: September 27, 2019, 04:17:58 AM »

I've seen a lot of debate about this, the consensus here is that continental snow doesn't really have much bearing on Arctic sea-ice. Recently (2017, 2018) the snow mass charts have gone off the scale in winter (ECCC had to make a new y-axis) and it really hasn't correlated with a change in Arctic sea ice melt.


More snow = more sunlight reflected = cooling.  But the best way to get a wider cover of snow on the continents adjacent to the Arctic is to disrupt the polar vortex and allow more cold arctic air to spread further away from the central Arctic, meaning the central Arctic becomes warmer.
Yes! Extra snowcover also has the impact of aiding -500MB anomalies in the continents, with ensuing cold blasts into the mid-latitude oceans a particularly potent method of advecting additional oceanic heat into the Arctic. Continental snowfall is good from the perspective of blunting incoming warmth to the Arctic that would originate from the continents, it is bad from the perspective that -500MB anomalies are effective at evacuating mid-latitude oceanic heat northwards, into the Arctic.

IF the continents are snowcovered AND the Arcic is fully ice-covered, the outcome of snow-covered continents is probably net beneficial to sea ice. However, if the continents are snowcovered and the Arctic pack is entirely surrounded by water -- as is currently the case -- perhaps this is when the oceanic feedbacks derivative of the -500MB anomalies really kick into overdrive. When the sea ice is surrounded by hundreds or thousands of miles of open water, the positive benefits of continental snowcover are lost as that air which would normally advect overtop the sea ice, depleted of heat and moisture, is instead often muddled by cyclonic activity as it meets the open waters of the ESS / Laptev/ whathaveyou.

I had not considered this juxtaposition before, but it would make quite a bit of sense in explaining why atmospheric circulation goes to particular sh*t in the autumnal months as of late.

15
Arctic sea ice / Re: The 2019/2020 freezing season
« on: September 24, 2019, 09:13:15 PM »
The land snow cover extent back to its normal values. The snowfalls and heat wave are on Greenland now. I will pay attention to the snow tracking because it will be important next melt season

16
The forum / Re: ASIF Statistics
« on: September 24, 2019, 05:42:28 PM »
I see them 'likes' as imaginary beautiful flowers to give away for free. There's no end to those flowers, they just keep on coming :).

17
Arctic sea ice / Re: Nullschool Animations
« on: September 22, 2019, 01:52:10 PM »
Hindcast: 9/18 to 9/22, Forecast: 9/22 to 9/26.
IWPD @ 850hPa, Wind + IWPD @ 850hPa (full-size versions)

[Instantaneous Wind Power Density: air density ρ, wind velocity v: ½ρv3]

18
Arctic sea ice / Re: 2019/2020 freezing season
« on: September 22, 2019, 04:46:32 AM »
Why is there always a race to be the person who gets to start one of these threads?

John Adams believed that the number one motive of human nature is not benevolence or a commitment to justice, but rather what he called the "rage for distinction." According to Adams, each of us insists on being the hero of his (or her) narrative.

19
Arctic sea ice / Re: Nullschool Animations
« on: September 18, 2019, 01:21:20 PM »
Hindcast: 9/14 to 9/18, Forecast: 9/18 to 9/22.
IWPD @ 850hPa, Wind + IWPD @ 850hPa (full-size versions)

[Instantaneous Wind Power Density: air density ρ, wind velocity v: ½ρv3]

20
Arctic sea ice / Re: The 2019 melting season
« on: September 16, 2019, 02:40:43 PM »
Updated full-size versions available in the Nullschool Animations thread:
https://forum.arctic-sea-ice.net/index.php/topic,2905.msg228895.html#msg228895

Hindcast: 9/12 to 9/16, Forecast: 9/16 to 9/20. Wind + IWPD @ 850hPa (tiny version)

21
Arctic sea ice / Re: Nullschool Animations
« on: September 16, 2019, 02:25:50 PM »
Hindcast: 9/12 to 9/16, Forecast: 9/16 to 9/20.
IWPD @ 850hPa, Wind + IWPD @ 850hPa (full-size versions)

[Instantaneous Wind Power Density: air density ρ, wind velocity v: ½ρv3]

22
Arctic sea ice / Re: The 2019 melting season
« on: September 16, 2019, 12:37:10 AM »
Well it's funny when bbr of all the prople, starts talking (read attacking) about somebody else's false predictions, which are according to his words not just honest mistakes (btw nothing the guy said at that point looked like trash that doesn't make any sense, CAB numbers weren't weak, but July was hot and we are still practically tied with 2016.) but trolling. Man you are literally famous for that on this forum, with much more ridiculous "predictions". Every time you see something you "like", you post these 10 day forecasts of every single run that helps your "case".

@aperson
It's not a denialist mistake to be wrong. Everybody is wrong sometimes with their predictions. It's just a mistake. What do we call people who voted for BOE option THIS YEAR, during this melting season. Or do you think that was more realistic than weatherdude's prediction. They were just wronglike him. That is it. No conspiracies or hidden meanings behind every false prediction. Some are more realistic, some are less.

Please guys stop attacking and bullying people every time there is somebody who has different prediction, compared to yours, even if they are wrong.  Cause you also are wrong a lot., like many people here, including me. Nobody could have predicted such a strong HP during the first half of the summer, especially after last few years (there was a talk last year or 2017 I remember very well, that because of the warming, cloudy cool summers are a new norm). And after all of that, nobody could have predicted such a slow August melt. It was proven dozens of times to all of us that Arctic is almost impossible to predict and full of surprises.

23
Arctic sea ice / Re: Nullschool Animations
« on: September 15, 2019, 01:53:48 AM »
some people here don't like it when new members...

I'm a thick-skinned relic. I don't mind getting extra hassles from others here -- nobody knows me and why would they suspect my psychedelic swirls are actually concerned with scientific content? Call me names, swear at me, whatever... but this professorial snarky-hints style (as if I'm just an undergraduate, so it's my job to figure out what the hell they want), it can nettle me -- refreshing my memory about why I hated school!

A godfather quote comes to mind: "What have I done to cause you to disrespect me so?"

Anyhow, I'm sorry to drag you back into this silly argument -- when people can just adjust their browser settings or site preferences and not have to act so unpleasant to us, when there are plenty more deserving candidates for accusations of abusing this site. If you'd forgive just a half-tsp of unsolicited advice from me, I'd urge you not to waste a moment's mental energy diagnosing the bizarre syndromes of haters. We got other stuff to do!

24
Arctic sea ice / Re: The 2019 melting season
« on: September 15, 2019, 01:11:03 AM »
I think you both can continue to post 1 post a day of videos. It is a good contribution. Make them a size so they don't autoload.
If someone doesn't like them and it really bothers them, this forum has a block feature, were you can select to hide posts from a certain user (then it says post is hidden, click to show).
There have been alot of people posting this season, you can't like what everyone contributes.

25
Arctic sea ice / Re: The 2019 melting season
« on: September 14, 2019, 09:49:26 PM »
I check nullchool every day, several times a day. I find these nullschool posts very insightful and  often generate insightful discussion. Aleph Null's hindcast/forecast animations are specially nice for me because I often only look at nullschool's forecast. Having the hindcast in a very quick animation right on time and often generating comments is very useful to me.

And it is right on topic. Animations of models of the current status of the melting season couldn't be more on topic.

There are advantages to linking videos instead of uploading, for example, having a broader audience, but it is more work.

This off topic. Complaints have been a common recurrence on this thread this season. Perhaps we need a "Complaints" thread where forum users can voice their dislikes and find acceptable solutions without polluting this thread?

26
Arctic sea ice / Re: The 2019 melting season
« on: September 14, 2019, 06:19:30 PM »
Animated gifs are roughly 3 times larger for the content I prepare.


Is that so? When an MP4 autoloads in backgroud no matter what (as i recently learned - thanks Oren!!), and everyone opening the thread causing IP traffic, the 'click to play' GIF (>700px) would save a shitton of traffic.


That said, i do enjoy your and Freegrass' animations and i do find them valuable. :)

27
Arctic sea ice / Re: Nullschool Animations
« on: September 14, 2019, 08:02:13 AM »
I hope others like it like i do! :D

28
Arctic sea ice / Re: Nullschool Animations
« on: September 13, 2019, 07:35:36 PM »
This one is awesome Aleph_Null! I've been wanting to do this also, but I still have to figure out how.

Sincere thanks to you & blumenkraft for the initial feedback. Maybe this place is a good graphic test bed. I'm still a bit skeptical of information overload here -- like there's so much going on it's impossible to take it all in. (A complication for me with some layered views I see.)

I'm an old graphic pro from a couple of incarnations ago, hacking about with my prehistoric version of Photoshop. The basic approach: two or more layers are merged into one, over and over, then the merged layers are output as jpegs, thence to EZGif. To pirate Aluminium's artwork I needed a little help from their splitter: https://ezgif.com/split

[EDIT: To be clear: I'm not worried about information overload here in the greenroom, I was referring to my own product -- trying to keep it simple enough to grasp.]

29
Arctic sea ice / Re: Nullschool Animations
« on: September 13, 2019, 01:36:01 PM »
I'm not sure if this is comprehensible, or just confusing.

It is really awesome. !!

30
Arctic sea ice / Re: Nullschool Animations
« on: September 13, 2019, 12:42:00 PM »
I'm not sure if this is comprehensible, or just confusing. I've combined Aluminium's last with the IWPD layer of my previous hindcast-forecast.

31
Arctic sea ice / Re: Nullschool Animations
« on: September 13, 2019, 08:43:15 AM »
This one is most useful. If you could merge the temps in there that would be perfect.

32
Arctic sea ice / Re: The 2019 melting season
« on: September 12, 2019, 01:35:13 PM »
Further illumination can be found in the Nullschool Animations thread (where, they say, Freegrass is available to all):
https://forum.arctic-sea-ice.net/index.php/topic,2905.0.html

Hindcast: 9/8 to 9/12, Forecast: 9/12 to 9/16.
Wind + IWPD @ 850hPa [Instantaneous Wind Power Density: air density ρ, wind velocity v: ½ρv3]

33
Arctic sea ice / Re: meaningless freezingseason/melting season chatter.
« on: September 12, 2019, 01:00:42 AM »
Yes I could see the dog, Freegrass, better viewed zoomed out on an average quality phone !

Reminds me a bit of this guy  ;)

34
Arctic sea ice / Re: Nullschool Animations
« on: September 11, 2019, 09:57:22 PM »
On guessing games and interpretation of data animation

The architects of the weather-data detection, assimilation, and prediction frameworks culminating in GFS & EURO might bristle at the suggestion that theirs, the most expensive and sophisticated stretch to play the odds in human history (not to mention humankind's premiere scientific accomplishment, imho), amounts to a guessing game. A super smart guessing game: a half-dozen interlocking differential equations conceived as an impossible dream by Vilhelm Bjerknes -- how could this work when it takes an army of human "computers" more than a year to figure out tomorrow's weather?

Somehow it all came together, with a little help from supercomputers, and from visionaries wild enough to see what happens if you fly into the eye of a hurricane. That's Harry Wexler, who bestowed my mantra: "The atmosphere is indivisible." From this mantra emerges all understanding. It'll take you clear through Climate Science to general enlightenment. Everyone's allowed one foolish hope. I've got dibs on that one...

Regarding the Arctic this summer, I hear consternation about continual disagreement between models in the 2019 melting-season thread. (Lurkers like me have been kindly re-christened "new ice" -- I don't know if this level of forecasting churn is unusual or not.) Lurking Dorian raises the question: given that a model's basic function is to project forward from past events, is it reasonable to expect a model capable of predicting the unprecedented?

So there are a couple of things my swirly suite of IWPD animations are meant to keep an eye on: the health of the planet, and how well the calculus of GFS holds up today, under apparently burgeoning chaotic factors. In particular, these animations intend to sharpen questions about the model to inquiries such as "What, where, when, and how did the forecast miss, in this hand of the guessing game?"

35
Arctic sea ice / Re: Nullschool Animations
« on: September 11, 2019, 05:16:27 PM »
I just need to figure out now how to make the transitions smoother between the frames.

Attached please find a brief test of EZGif's crossfade (I always convert to mp4 before downloading), with frame-delay set to 100 and crossfade-delay set to 20. This is the first ten frames of my jitter test, above, slowed down a lot.

I seem to recall attaining a BA degree (fwiw!) in painting & animation. Somehow I gravitate to the non-lucrative pursuits. At any rate, perhaps it's interesting that my current focus (the swirly suites of IWPD) calls for an intentionally jerky look (because I want to scrutinize each 3-hour guess as it crosses my screen), while you aspire to the naturalistic feeling of the unforgettable COsc videos you posted. We both explore graphics to understand how weather works, but from different angles, at the moment -- with regard to crossfade, at least!

Note: This test of ten frames with crossfade makes a larger file than 50 frames without.

36
Arctic sea ice / Re: Nullschool Animations
« on: September 11, 2019, 05:15:13 PM »
When I was posting videos, I used ffmpeg to convert GIFs to MP4s. I just took a quick look on Google and there are all kind of options for smoothing videos by interpolating frames.

https://www.google.com/search?q=ffmpeg+smoothing

37
Arctic sea ice / Re: The 2019 melting season
« on: September 11, 2019, 04:31:57 PM »
What's the official minimum then?

Currently, according to JAXA data, it is 4,158,349 km^2. Achieved on September 4th.

The extent data is misleading, at best.  The rank matters little - what matters is the sea ice thickness and the condition of the ice in general.

Unfortunately, the sea ice extent graphs are given the most attention rather than sea ice thickness and fragmentation (and sea surface temperature).

The sea ice extent is a dubious measurement, as highly fragmented slush should not be considered "extent", but it does seem to get included.  Therefore, the "extent" of the low quality single year ice of 2019 is compared against the "extent" of the multi year ice of, say 1995 - which is incorrect - it's comparing apples to oranges.

We need to be focusing on the multi year ice, sea ice thickness  - not the "extent" data.

On that note, how's that multi-year ice doing in 2019?

38
Arctic sea ice / Re: The 2019 melting season
« on: September 11, 2019, 10:03:19 AM »
September 6-10.

Looking at this, one might think there was an increase on the Atlantic side.

Big nope though. It's due to widening gaps.

39
Arctic sea ice / Re: Nullschool Animations
« on: September 11, 2019, 06:25:55 AM »
This thread is a good idea.
In any case, better a smaller audience but that of of willing users who choose to participate and appreciate the effort.
+1

I'm one of the regulars and appreciate the effort!

40
Arctic sea ice / Re: Nullschool Animations
« on: September 11, 2019, 03:22:15 AM »
This thread is a good idea.
In any case, better a smaller audience but that of of willing users who choose to participate and appreciate the effort.

41
Arctic sea ice / Re: The 2019 melting season
« on: September 10, 2019, 05:20:45 PM »
Nah, what's that face Simon? Being corrected on something doesn't vindicate such a face. It's all good mate. :)

And thanks a lot for the 'veteran' compliment. Very kind of you. :D

42
Arctic sea ice / Re: Nullschool Animations
« on: September 10, 2019, 05:11:42 PM »
The A-team really went for it...

I came across this interesting reply in the animated gifs thread:

One of these days I'm going to read through this thread again from start to finish, and will then hopefully fully understand what it is you guys are doing with what, and maybe then I can be a target user who is able to express what he needs.

Sorry for not understanding already. My head is too full. I know you're doing awesome stuff, grade A citizen science.

At the moment, I'm having similar difficulties. Perhaps I'll remain a modest admirer of such works for now. I just hope not to come out with a meteorological projection as mistaken as the Sharpie Over Alabama (wasn't that a Billie Holliday song?)! My "target user" is me. I just make what I want to see, selfish as hell.

Incidentally, Freegrass: Thanks again for reminding folks of this thread in the main thread. I'll do the same from now on. No point sprucing up the place if we never get any company.

43
Arctic sea ice / Re: Nullschool Animations
« on: September 10, 2019, 02:55:44 PM »
I really need to learn more about GIMP, and how to create great animations with it.

You may wish to peruse the "Creating Animated GIFs" thread?

44
Arctic sea ice / Re: Nullschool Forecast Graphics
« on: September 10, 2019, 10:07:51 AM »
Oops, I got so relaxed in your nice den here, Freegrass, I forgot to say why I like hindcasts. Watching the smoothed-out choreography of the hindcast versus the toggling, increasingly uncertain-looking movement quality of the forecast... that's what interests me. When I realized that Dorian was playing the same guessing game we've seen in the Arctic all year, I wanted to find out more about how models work, and whether chaotic factors are noticeably rising.

Thanks for listening!

45
Arctic sea ice / Re: Nullschool Forecast Graphics
« on: September 10, 2019, 09:59:08 AM »
I also thank you, Freegrass, but I'm also interested in hindcasts. Perhaps this is an appropriate place for me to explain why -- without spawning an OT clog in the main thread where angels fear to tread? (Speaking of chatter: I must say I am continually blown away that technology at the level of Nullschool is freely available. The more I learn about atmospheric science, the more amazed I am.)

With my production technique (using a Photoshop doc to stack up screengrabs -- what the hell) I'm seeing a lot more volatility in hindcasts than might be expected. I mean, this is supposed to be past-tense, but it hasn't settled down, evidently, because data assimilation continues for awhile.

That was my impression, but I wanted proof. So I put together the following to illustrate the jitter of data assimilation -- with 24 hours between screengrab runs (the more recent, with the same timestamp, appearing second). Sorry this one has to be so jittery.

46
Arctic sea ice / Re: Nullschool Forecast Graphics
« on: September 10, 2019, 04:03:19 AM »
Good job on making this thread Freegrass. :)

47
Arctic sea ice / Re: Nullschool Forecast Graphics
« on: September 09, 2019, 07:39:09 PM »
Thank you for these, Freegrass!

48
Arctic sea ice / Re: The 2019 melting season
« on: September 09, 2019, 03:52:04 PM »
Up-thread, the remnants of Hurricane Dorian are forecast to be south of Svalbard by Saturday. An alternative forecast from the BBC Weather site shows it arriving a little earlier and a little to the south-west of Svalbard. Following this it's forecast to move west and climb onto the eastern parts of Greenland until Sunday where, presumably, it would drop a ton of snow.
I'm not sure how this website below works outside the UK. If you home out the forecast map, it cover the entire globe bar the poles.
https://www.bbc.co.uk/weather/map

49
Arctic sea ice / Re: Nullschool Forecast Graphics
« on: September 09, 2019, 03:27:12 PM »
That's a good idea, Freegrass. :)

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Arctic sea ice / Re: The 2019 melting season
« on: September 08, 2019, 09:57:13 PM »
I suspect that the famous bottom melt, as kind of a negative feedback, is not anymore what it used to be.

As luck would have it the NSIDC discussed surface versus bottom melt in the the latest Arctic Sea Ice News:

"Summer’s not over until bottom melt ends"

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Although Arctic air temperatures are now falling below freezing, sea ice loss will likely continue for several weeks as heat stored in the ocean melts the underside of sea ice.

Here's the accompanying graph. The caption reads:

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This 2005 to 2006 time series from the Beaufort Sea shows ice thickness (red line), growth rate (blue bars with negative values), bottom melt (blue bars with positive values), and surface melt (dark blue line with points). Both surface and bottom melt started on June 10. Surface melt peaked on August 1, and peak bottom melt was two weeks later on August 15. Surface melting ended on August 24, while bottom melting continued until October 24.

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