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Author Topic: The 2019 melting season  (Read 1115090 times)

Sterks

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Re: The 2019 melting season
« Reply #5500 on: August 12, 2019, 12:18:42 AM »
And what’s with the Politics? Do you think you know me?
Is that the reason why you jump?
Dark beings around it seems.

Conservatives always play the victim, as you are.
Yet, your posting history shows plenty of bullying and baseless over-conservative claims, backed by rudeness and an aversion to facts that disprove your pet theories.

Again, you were proven wrong in the data thread which you attempted to derail, and you couldn’t care less. You think it’s your god-given right to be overly-Conservative and critical of others who are actually trying to put the puzzle pieces together.

So much nonsense that you post...
No apologies, no reflection, no remorse.
Probably a Baby Boomer too.
I have replied to this crap in Forum Decorum, including a request to Neven that you are banned

gerontocrat

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Re: The 2019 melting season
« Reply #5501 on: August 12, 2019, 12:22:14 AM »
Probably a Baby Boomer too.
I apologise deeply on behalf of my mother for her carelessness in giving birth to a baby boomer.
I am taking myself to a dark corner to weep and wallow in my misfortune. Woe is me.
"He was despised, rejected of men, a man of sorrows, and acquainted with grief" (Isaiah 53:3)

I guess this is off-topic but.....

"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

gerontocrat

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Re: The 2019 melting season
« Reply #5502 on: August 12, 2019, 01:02:22 AM »
In any case, as Gerontrocrat remarked, it may not be a question of looking at a GIF but analysing the regional numbers of area that he brings.

Those numbers are based on the same data, so how is that any different? The point of looking at images from various sources is to give intuition to guide interpretation of what the numbers may mean.
"Those numbers are based on the same data". Nope?

My sea ice area postings use NSIDC 5 day average data from their 25x25km resolution sensor. So, not one day,  and when looking at NSIDC's  images not such an obvious thickening of ice concentration where AMSR2 images show it.

I think I read somewhere that NSIDC's sensor, being much less sensitive and such lower resolution, occasionally produced fewer oddities under certain weather conditions.
"Para a Causa do Povo a Luta Continua!"
"And that's all I'm going to say about that". Forrest Gump
"Damn, I wanted to see what happened next" (Epitaph)

DrTskoul

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Re: The 2019 melting season
« Reply #5503 on: August 12, 2019, 01:09:12 AM »
I am amazed how easily the human is deceived and can "see" patterns with minimal data....

Sterks

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Re: The 2019 melting season
« Reply #5504 on: August 12, 2019, 01:11:13 AM »
I am amazed how easily the human is deceived and can "see" patterns with minimal data....
I am amazed how slow machines are in learning the most basic patterns a human can see.

Sterks

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Re: The 2019 melting season
« Reply #5505 on: August 12, 2019, 01:12:09 AM »
In any case, as Gerontrocrat remarked, it may not be a question of looking at a GIF but analysing the regional numbers of area that he brings.

Those numbers are based on the same data, so how is that any different? The point of looking at images from various sources is to give intuition to guide interpretation of what the numbers may mean.
"Those numbers are based on the same data". Nope?

My sea ice area postings use NSIDC 5 day average data from their 25x25km resolution sensor. So, not one day,  and when looking at NSIDC's  images not such an obvious thickening of ice concentration where AMSR2 images show it.

I think I read somewhere that NSIDC's sensor, being much less sensitive and such lower resolution, occasionally produced fewer oddities under certain weather conditions.
Fair points.

Freegrass

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Re: The 2019 melting season
« Reply #5506 on: August 12, 2019, 01:17:46 AM »
A new high pressure system could be entering the arctic in 5 days from now. 1040 hPa is quite high right?

https://earth.nullschool.net/#2019/08/16/1800Z/wind/surface/level/overlay=mean_sea_level_pressure/orthographic=-37.55,98.87,1500/loc=-172.775,66.338
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RoxTheGeologist

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Re: The 2019 melting season
« Reply #5507 on: August 12, 2019, 01:37:20 AM »
I am amazed how easily the human is deceived and can "see" patterns with minimal data....

Canals on Mars.

Rod

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Re: The 2019 melting season
« Reply #5508 on: August 12, 2019, 01:39:10 AM »
Area data is notoriously difficult to interpret this time of the year. The graphs that Gerontocrat posts show what they show, but it is difficult to draw conclusions about melting or freezing based solely upon the graphs. 

As shown below, a strong storm positioned itself over the Beaufort on August 6.  A break in the clouds on August 9 shows that there is no freezing.  The view from August 10 shows clouds with ice crystals positioned in that area. 

That region of the Beaufort has held strong all season, but the last few days have seen the floes turned into ice stringers.   It is doubtful that ice will last much longer regardless of what the area charts are currently showing. 

I’m not posting this to make a prediction about whether 2019 will beat 2012, but it does look like there will be some significant loss in the Beaufort extent numbers in the next few days. 

uniquorn

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Re: The 2019 melting season
« Reply #5509 on: August 12, 2019, 01:56:25 AM »
In short: Bremen concentration maps from a cloudy days are almost useless.
Appreciate you may be trying to make a point, but without the cloudy days we don't have a continuous record and clouds (and other interference) are relatively easy to identify in an animation.

Wildcatter

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Re: The 2019 melting season
« Reply #5510 on: August 12, 2019, 02:08:15 AM »
What's interesting is the tug of war at 500hpa that's been going on and continues, at least over the next 3-5 days. After that last cyclone, 570-575mb heights moved over the entire northern Arctic with those temps, also over Baffin Bay with eastern CAA and N. Greenland feeling it. It looks like the next 3-5 days we might see similar 565-570mb stretching right across the pole. Negative phase oscillation? "Cold" front expected across most of US

Also a very interesting pressure gradient that looks like it'd encourage export out to Fram/Barents. High pressure over Greenland/most of CAA, as well as the ESS/laptev, across the pole, with low pressure in the Kara/Barents and some good wind speeds. Not sure what to make of that, doesn't look great for the Laptev or CAB (i imagine worse if it's sitting under the effects of higher mb at 500hpa)

Doesn't look very encouraging for all that CAA/Greenland border ice either. Haven't been able to get a very good look with AMSR2, but NSIDC has a better view. "Not great" would probably be accurate, haha.

i just thought the geo height and oscillation aspect was interesting, someone can feel free to correct me or elaborate.

bbr2314

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Re: The 2019 melting season
« Reply #5511 on: August 12, 2019, 03:37:18 AM »
It is pretty crazy how much ice remains in Hudson Bay as of 8/12. There is still quite a bit in the southern part! I wonder if any floes will survive til winter, the 12z EURO shows cold weather setting in imminently, and the part of the Bay that is normally ice-free for the longest time each summer has been ice-covered abnormally long this year, keeping high-ish SSTs confined to the NE part of HB (which is paradoxically normally the coldest part).

petm

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Re: The 2019 melting season
« Reply #5512 on: August 12, 2019, 03:50:31 AM »
My sea ice area postings use NSIDC 5 day average data from their 25x25km resolution sensor. So, not one day,  and when looking at NSIDC's  images not such an obvious thickening of ice concentration where AMSR2 images show it.

Good to know. I admit to not having thoroughly studied your methods. Certainly multi-day averages are much better with noisy data. And I too have read that the lower wavelength / resolution bands are less prone to cloud artifacts. Thanks again for all your excellent reports.

mdoliner

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Re: The 2019 melting season
« Reply #5513 on: August 12, 2019, 04:03:41 AM »
According to the Stephan-Boltzman Law E = σT4

With σ = 5.670374419...×10−8 W⋅m−2⋅K−4

T=273 so T4 = 5.55 x 109

so  σT4 = 5.670374419 x55.5   is about 310 W⋅m−2

Insolation when the sun is straight overhead is 1370 W⋅m−2 .

When the sun is at an angle it is 1370 sin θ.

So when the sun is at an angle of arcsin 310/1370 = .226 insolation is equal to blackbody radiation.

That angle is about 13 deg. So when the sun is lower than 13 deg, the low frequency radiation from open water roughly balances the insolation.

Open water increases warming when the sun is high, but is a negative feedback when the sun is lower than 13 deg.

Archimid

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Re: The 2019 melting season
« Reply #5514 on: August 12, 2019, 04:36:52 AM »
What about evaporation?
I am an energy reservoir seemingly intent on lowering entropy for self preservation.

subgeometer

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Re: The 2019 melting season
« Reply #5515 on: August 12, 2019, 04:40:52 AM »
2worldview images from9 August

...The second shows the immense Siberian smoke plume... heading over Severbaya Zemlya and the ice edge

Now *that's* interesting. Nothing like sprinkling something dark over the ice to induce melt.

It's lucky this is happening as the sun is on the wane - climatologically we are only a few days from going under 0C north of 80 degrees, if it were June or the first half of July the effects on energy accumulation from insolation would be a lot worse. Just how much it would darken the ice I'll leave to those who have the expertise

As it is this vast influx will continue through the week, and smoke is likely to appear in every corner of the Arctic Ocean. For example smoke dense enough to block out the sun is forecast off North Greenland in 2 days. Right now a large area of the CAB adjacent to the Laptev s under a cloud whose aerosol density s up to 4.5 AOD(1 AOD is enough to block the sun if I understand correctly). Any polar bears out there on the dwindling ice are in for a weird eerie experience. Pink skies and blood red light?

I've attached 2 Wndy/Coperncus Aerosol forecast maps, as well as the smoke hosing the Laptev on Worldvew yesterday, and a vew of the ice edge near Severnaya Zemlya, showing strong melt after the first couple of days of warmth

bbr2314

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Re: The 2019 melting season
« Reply #5516 on: August 12, 2019, 04:45:40 AM »
The smoke situation is the worst-ever this year, I believe. This will only continue as we head into the 2020s. It is horrific, although down in the mid-latitudes we will probably have some beautiful sunsets as these clouds disperse most everywhere.

Who needs nuclear winter when you have massive fires raging in the forests and permafrost up north that get transported globally?

bbr2314

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Re: The 2019 melting season
« Reply #5517 on: August 12, 2019, 04:50:08 AM »
https://forecast.weather.gov/product.php?site=afg&product=PNS&issuedby=afg

Public Information Statement...CORRECTED
National Weather Service Fairbanks AK
800 PM AKDT Sat Aug 10 2019

...Lightning Detected within 300 Miles of North Pole Today...

A number of lightning strikes were recorded between 4pm and 6pm
today within 300 miles of the North Pole. The lightning strikes
occurred near 85 degrees north, 120 degrees east, which is about
700 miles north of the Lena River Delta of Siberia. This lightning
was detected by the GLD lightning detection network which is used
by the National Weather Service. This is one of the furthest
north lightning strikes in Alaska Forecaster memory.

$$

JB

Rod

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Re: The 2019 melting season
« Reply #5518 on: August 12, 2019, 04:55:07 AM »
I’m really surprised that the lightning strikes 300 miles from the North Pole yesterday did not cause more discussion on the forum. 

The scientists on climate Twitter could not find any instance of lightning so far north.

It was a strange, and in my opinion important, event.  The arctic is changing!

subgeometer

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Re: The 2019 melting season
« Reply #5519 on: August 12, 2019, 04:57:46 AM »
Area data is notoriously difficult to interpret this time of the year. The graphs that Gerontocrat posts show what they show, but it is difficult to draw conclusions about melting or freezing based solely upon the graphs. 

 

Yesterdays Bremen AMSR2 also shows high concentration north of the Laptev bite, despite the clear fraying visble on earlier days on the map and worldview, and the warm temps under thick cloud. The cloud is fooling the instrument - weather artifacts are often visible. Animations by Aluminium etc show the passage of cloud bands as areas of fleetingly increased concentration- phantom area

Temps have to drop well below freezing for new ice to form, -11C is the figure usually quoted, and nowhere has been anywhere near that cold yet, and won't be for at least a couple of weeks yet. Regional area increases can come from transport. Any absolute area increases now are spurious, solid floes collapsing to rubble, and the effects of dispersal combined with quirks of the algorithm and low resolution of the instruments, as well as the effects of thick clouds

jdallen

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Re: The 2019 melting season
« Reply #5520 on: August 12, 2019, 05:19:19 AM »
A new high pressure system could be entering the arctic in 5 days from now. 1040 hPa is quite high right?

https://earth.nullschool.net/#2019/08/16/1800Z/wind/surface/level/overlay=mean_sea_level_pressure/orthographic=-37.55,98.87,1500/loc=-172.775,66.338
High pressure in 5 days, if widespread, not so much a problem for the ice. Insolation is dropping like a stone.

However, 1040 PA combined with a low someplace else... potential trouble for the ice.  Especially as this high is over the Chukchi and with 40+pa gradient could shove ice out of the main basin into "superheated" waters of the Beaufort.
This space for Rent.

wdmn

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Re: The 2019 melting season
« Reply #5521 on: August 12, 2019, 05:32:47 AM »
Another 100k loss in JAXA extent suggests that there is still a lot of melting momentum. Is there enough weather left in August to sustain it?

petm

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Re: The 2019 melting season
« Reply #5522 on: August 12, 2019, 05:42:42 AM »
Aug 6 - 11

5-day minimum (left) v. original (right)

click

petm

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Re: The 2019 melting season
« Reply #5523 on: August 12, 2019, 06:09:53 AM »
Lots of areas ready to melt in the next day or two.

budmantis

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Re: The 2019 melting season
« Reply #5524 on: August 12, 2019, 07:06:38 AM »
Probably a Baby Boomer too.
I apologise deeply on behalf of my mother for her carelessness in giving birth to a baby boomer.
I am taking myself to a dark corner to weep and wallow in my misfortune. Woe is me.
"He was despised, rejected of men, a man of sorrows, and acquainted with grief" (Isaiah 53:3)

I guess this is off-topic but.....


 Bravo!!!

Freegrass

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Re: The 2019 melting season
« Reply #5525 on: August 12, 2019, 07:42:45 AM »
A new high pressure system could be entering the arctic in 5 days from now. 1040 hPa is quite high right?

https://earth.nullschool.net/#2019/08/16/1800Z/wind/surface/level/overlay=mean_sea_level_pressure/orthographic=-37.55,98.87,1500/loc=-172.775,66.338
High pressure in 5 days, if widespread, not so much a problem for the ice. Insolation is dropping like a stone.

However, 1040 PA combined with a low someplace else... potential trouble for the ice.  Especially as this high is over the Chukchi and with 40+pa gradient could shove ice out of the main basin into "superheated" waters of the Beaufort.

I assume it's unusual that a high pressure system like this enters the arctic this late in the season?
If the latest Nullschool 5 day forecast holds - which is doubtful - strong warm winds and rain will be hitting the CAP again. More heat and smoke from Siberia will be sucked into the arctic. This can't be good for the ice. I'm already thinking that next year is gonna be an annus horribilis...
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subgeometer

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Re: The 2019 melting season
« Reply #5526 on: August 12, 2019, 07:52:28 AM »
Can this ice around 85-6N survive another month? If the waether cools quickly, and its calm, maybe, though it will look awful.

JAXA dropped 110K to 5million km2 today. The average drop from now to minimum in 2010s has been about 1.3 million, so its unlikely to not beat 2016 (4.03million)into 3rd. We're currently 110K above 2012 on this chart(about even on NOAAs, and 2019 retains a dwindling lead according to Bremen), so 2019 remains in the hunt for the record.

There's a lot of vulnerable ice. I've included an edited Bremen map from 11 August to show the location of the Worldview image(red square) and the ice that I think will likely survive(inside purple line) and that which is at risk of melting out, as a tentative stab at a minimum projection

El Cid

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Re: The 2019 melting season
« Reply #5527 on: August 12, 2019, 08:49:14 AM »
Aug 6 - 11

5-day minimum (left) v. original (right)

click

petm, these images are truly great! keep posting them every day if you can

thx

Aluminium

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Re: The 2019 melting season
« Reply #5528 on: August 12, 2019, 09:17:48 AM »
August 7-11.

2018.

bosbas

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Re: The 2019 melting season
« Reply #5529 on: August 12, 2019, 09:31:28 AM »
Some breaking up in the CAA near Mackenzie King

Glenn_Tamblyn

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Re: The 2019 melting season
« Reply #5530 on: August 12, 2019, 09:59:28 AM »


Insolation when the sun is straight overhead is 1370 W⋅m−2 .



Not sure your 1370 figure is correct. Yes the solar intensity outside the atmosphere is around that number. But not all of it gets through the atmosphere - some is absorbed, some is reflected. The more usual value for peak insolation anywhere on earth, from Sun directly overhead, is more like 1000 W.m-2

aslan

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Re: The 2019 melting season
« Reply #5531 on: August 12, 2019, 10:01:36 AM »
I’m really surprised that the lightning strikes 300 miles from the North Pole yesterday did not cause more discussion on the forum. 

The scientists on climate Twitter could not find any instance of lightning so far north.

It was a strange, and in my opinion important, event.  The arctic is changing!

This is from work, so no one has seen the following pictures... The IFS 0.125° for the 11th at 00Z, wet bulb potential temperature at 850 hPa, vorticity at 850 hPa (above 16, step 4), SLP, thickness 500 (Z500-Z100). There is  a front with a ribbon of vorticity to the North, stretching from the low over Barents to the Chucki sea, with low and mid level clouds, as visible from sat pictures. But associated with the low over Laptev, to the west of the head of the low, there is a maximum of vorticity. Sounding show mid level instability from ~800 hPa to ~250hPa with ~100 to ~200 J/Kg. Marginal, be with good forcings enough for TS.
As Rod said, this is significant.
For one part, this is an illustration of the evolving Arctic. Again, CBs were probably not directly linked to the crazy warm SST, but it is definitively showing that Arctic is warming. The warm air advection was extreme, and was able to carry a potentialy instable airmass up to 85°N. Mid level CBs at the head of a thermal wave are not a thing of the Arctic, up to today...
For the other part, this also means that cyclogenesis is on the move on the Arctic. This low had some characteristics of a warm seclusion with a slight max of temperature, TA and wind around 850 hPa - 900 hPa. Cold, pure baroclinic process are loosing a bit of grip and now warm core process and moist instability is starting to play a role. For the second point, it was of course more evident with the low over Beaufort at the start of the month for example. Here a lone CB will not make any meaningfull difference of course. But next year it could be 10 CBs, then etc... And on the end it will change the cyclogenesis process. It could also be noted that Laptev sea being shallow, it could quickly warm without sea ice. With Siberia snow free earlier and earlier, this could mean a quick increases of moist instability with a warming Arctic.

oren

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Re: The 2019 melting season
« Reply #5532 on: August 12, 2019, 10:21:25 AM »
Quote
There is surface refreezing at the level of several 100,000 km2
Note to Sterks: I originally thought you referred to sea surface. Now that I understand you meant melt ponds refreezing, this is certainly possible at this time of year. But looking at the Bremen 6-11 animation by petm, the purple areas seem to move around, so I still doubt this effect explains much of what we are seeing.
In any case, it's best to post this along with 2m temp reanalysis data as supporting evidence, rather than rely only on satellite microwave data.
« Last Edit: August 12, 2019, 11:04:27 AM by oren »

Jim Hunt

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Re: The 2019 melting season
« Reply #5533 on: August 12, 2019, 10:52:03 AM »
I’m really surprised that the lightning strikes 300 miles from the North Pole yesterday did not cause more discussion on the forum.

See also the "Iced Lightning" thread:

https://forum.arctic-sea-ice.net/index.php/topic,1603.msg221255.html#msg221255
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

SimonF92

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Re: The 2019 melting season
« Reply #5534 on: August 12, 2019, 12:14:02 PM »
It is pretty crazy how much ice remains in Hudson Bay as of 8/12. There is still quite a bit in the southern part! I wonder if any floes will survive til winter, the 12z EURO shows cold weather setting in imminently, and the part of the Bay that is normally ice-free for the longest time each summer has been ice-covered abnormally long this year, keeping high-ish SSTs confined to the NE part of HB (which is paradoxically normally the coldest part).

I doubt it will survive until winter, but it is very interesting given the state of the CAB and probably heralds a pretty robust freezing season in the Hudson

echoughton

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Re: The 2019 melting season
« Reply #5535 on: August 12, 2019, 12:33:49 PM »
It is pretty crazy how much ice remains in Hudson Bay as of 8/12. There is still quite a bit in the southern part! I wonder if any floes will survive til winter, the 12z EURO shows cold weather setting in imminently, and the part of the Bay that is normally ice-free for the longest time each summer has been ice-covered abnormally long this year, keeping high-ish SSTs confined to the NE part of HB (which is paradoxically normally the coldest part).

COULD WE BE WITNESSING A BHBE ...in the making??? (If we don't, I think it would be strange)

Sterks

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Re: The 2019 melting season
« Reply #5536 on: August 12, 2019, 12:37:51 PM »
The weekly variation, UH AMSR2. Aug 4 to Aug 11, with 2012 Aug 3 to Aug 10 as an extra this GAC week.

This year the Pacific edge is absolutely immobile, while it was very active part a week ago.
It was obliterated by the GAC in 2012.
Expect more action this week due to weather, and yet expect 2012 get well below in extent.

We are getting close to respond the question 'did the GAC just finish ice that was going to melt anyway? " with a No (IMO)

aslan

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Re: The 2019 melting season
« Reply #5537 on: August 12, 2019, 01:05:54 PM »
This said, even without GAC, weather is going to be very rough on the Pacific side. Low over Chukchi is not so hollow, but there is strong gradient, and mean winds more than 30 kts are going to occur. Sea is going to be not so friendly, with wave action. As others said, GAC 2012 pumped heat from deep ocean, but this year there is way enough heat at surface for melting sea ice edge with a good shaker mixing. Same can be said on the Atlantic side. The low over Kara is only going to a bit below 1000 hPa, but interacting with a 1030 high, this is going to be a wild ride for sea ice in coming days. Hopefully it will not last, but damages are likely in the next 2 - 3 days. It should be noted that some mid level instability is again modelized in the WAA coming from Siberia  :P

GoodeWeather

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Re: The 2019 melting season
« Reply #5538 on: August 12, 2019, 01:20:28 PM »
There is another separate thread to compare this year to 2012.  There is too much noise in this thread already when comparing 2019 to other years.  People come to this thread to discuss this year and the dynamics that are causing it to melt not analoging it to other years.

petm

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Re: The 2019 melting season
« Reply #5539 on: August 12, 2019, 02:27:01 PM »
petm, these images are truly great! keep posting them every day if you can

Thanks for the encouragement, El Cid. I'll do my best.

Sterks

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Re: The 2019 melting season
« Reply #5540 on: August 12, 2019, 02:41:16 PM »
There is another separate thread to compare this year to 2012.  There is too much noise in this thread already when comparing 2019 to other years.  People come to this thread to discuss this year and the dynamics that are causing it to melt not analoging it to other years.
1. Says who. Are you policing the Forum now?
2. I am posting 2019 AMSR2 1-week evolution as I've been doing every week. This week with the 2012 bonus cause the GAC happened.
3. Almost any 2019 vs 2012 discussion is relevant to melting season 2019, the opposite not true.
4. Your post is the most significant noise I have detected from this thread today, to be frank. Void of content or discussion or 'dynamics'.

Nightvid Cole

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Re: The 2019 melting season
« Reply #5541 on: August 12, 2019, 03:16:55 PM »
What about evaporation?

The high Arctic usually has relative humidity values of at least 90% and often near 100%. This would largely suppress evaporative cooling.

Archimid

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Re: The 2019 melting season
« Reply #5542 on: August 12, 2019, 03:21:57 PM »
Where can I find the data on those relative humidity values and how have they changed over time?
I am an energy reservoir seemingly intent on lowering entropy for self preservation.

Shared Humanity

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Re: The 2019 melting season
« Reply #5543 on: August 12, 2019, 03:45:15 PM »
Aug 6 - 11

5-day minimum (left) v. original (right)

click

Thank you petm. Keep this coming for the remainder of the melt please.

Jim Hunt

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Re: The 2019 melting season
« Reply #5544 on: August 12, 2019, 04:14:20 PM »
Whilst trying to work out which icebreaker is where in the Northwest Passage at present I've just discovered that Oden is currently in close proximity to the Ryder Glacier in northwest Greenland:

https://polarforskningsportalen.se/en/arctic/expeditions/ryder-2019

https://www.cruisemapper.com/?imo=8700876
Reality is merely an illusion, albeit a very persistent one - Albert Einstein

philopek

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Re: The 2019 melting season
« Reply #5545 on: August 12, 2019, 05:31:52 PM »


Insolation when the sun is straight overhead is 1370 W⋅m−2 .



Not sure your 1370 figure is correct. Yes the solar intensity outside the atmosphere is around that number. But not all of it gets through the atmosphere - some is absorbed, some is reflected. The more usual value for peak insolation anywhere on earth, from Sun directly overhead, is more like 1000 W.m-2

Outside the atmosphere there is no angle IMO and if there would be, what do i know what language bending exists, it would be irrelevant because outside the atmosphere the insolation and values are constant whever a body is exposed to the sun, there is only 100% or 0% insolation as far as I know, except perhaps the few seondes when some of the gravity bent sun-beams are sneaking around a large body in space, i.e the moon or another planet.

philopek

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Re: The 2019 melting season
« Reply #5546 on: August 12, 2019, 05:42:17 PM »
There is another separate thread to compare this year to 2012.  There is too much noise in this thread already when comparing 2019 to other years.  People come to this thread to discuss this year and the dynamics that are causing it to melt not analoging it to other years.

Probably you're right for many users while I honestly come to this and any other thread to learn new stuff, read interesting ideas, facts and opinions and care very little whether they're exactly ON topic or a diversion born from content that is cross-topic.

Further i'm not sure whether a short exchange would be very fruitful it it were traveling form thread to thread, each time a new viewing angle with new input touching other topics would made that appropriate.

Whoever is REALLY interested to get the most out of an exchange of information should perhaps allow for a slightly wider horizon, this would make it much easier to produce real solutions instead of only lamenting the obvious but in fact reaching no escape routes.

In short, too much on topic is killing useful discussions and separates further instead of uniting reasoning as well as people.

If someone is a weatherman reading the melting thread he will provide his input based on his special knowledge and who is too lazy to read a few pages of OT is not really dedicated IMO.

ALL knowledge is useful and there is a level of OT that is very healthy.

I love this thread most of the time and i know that this very post as well as yours are OT and hundreds of complaints about OT, other minor stuff and the often following back and forth bickering are clogging threads far more than the (useful) OT itself.

This is just my opinion which belongs to me and i wrote this because the complaints bother me more than the interesting bywork called OT.

pleun

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Re: The 2019 melting season
« Reply #5547 on: August 12, 2019, 06:15:59 PM »
+1

FishOutofWater

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Re: The 2019 melting season
« Reply #5548 on: August 12, 2019, 06:31:28 PM »
Summer stratospheric dynamics have changed drastically since 1979. The combination of ozone loss in the upper stratosphere and warming of the lower atmosphere have enabled a shift to negative Arctic oscillation index values in the summer. 2019 is the most persistently negative AO of any summer since 2019 that I have seen. It's shocking how different the cross section of thermal anomalies over the pole was in the early 1980s.

This (combined with many other studies) leads me to think that the loss of polar ozone played a role in the loss of sea ice since 1979 and now the  loss of sea ice is feeding back creating a large shift in atmospheric dynamics.
« Last Edit: August 12, 2019, 07:19:34 PM by FishOutofWater »

ReverendMilkbone

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Re: The 2019 melting season
« Reply #5549 on: August 12, 2019, 06:33:54 PM »
Lightning strikes within 300 miles of north pole.

https://twitter.com/NWSFairbanks/status/1160456516849172480