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Often Distant

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Re: The 2019 melting season
« Reply #5450 on: August 10, 2019, 11:00:21 AM »
More so summer equals fire. Awful how it's not uncommon.
« Last Edit: August 10, 2019, 11:10:04 AM by Often Distant »

Often Distant

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Re: The 2019 melting season
« Reply #5451 on: August 10, 2019, 12:10:49 PM »
Last year remnants in the East Siberian Sea remained throughout the season.
Here's a comparison between the years, though 2018 is one month later on.
2019 is the smoking one.
2020 hangs on first year ice.

petm

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Re: The 2019 melting season
« Reply #5452 on: August 10, 2019, 04:12:56 PM »
July 13 - Aug 9 (4 weeks)

This animation is a 5-day minimum, not median.

Using the minimum introduces some artifacts. Areas of low concentration ice that are moving will leave a 5-day memory on every pixel they cross; for example, areas of part water and part moving ice, such as the Beaufort edges or ESS, will look like they have more open water than they really do. Similarly, if there are low concentration cloud artifacts, they will also be preserved for 5 days. Also, if new ice were forming, it would likewise not show up for 5 days; but no new ice is forming yet.

However, in my experience, the vast majority of artifacts in these maps are high concentration cloud artifacts, and using the minimum does well at removing most of those. If you follow the evolution of the ice edge this seems to do a good job and maybe hints at what might be coming, such as a continued edge retreat in the Beaufort (minus advection) and NW of the Laptev bite.

Maybe think of this map as something like a worst-case scenario. Use the originals (on the right) as a guide to aid interpretation.

Large file - click.
« Last Edit: August 10, 2019, 04:18:29 PM by petm »

sailor

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Re: The 2019 melting season
« Reply #5453 on: August 10, 2019, 05:39:16 PM »
July 13 - Aug 9 (4 weeks)

This animation is a 5-day minimum, not median.

Using the minimum introduces some artifacts. Areas of low concentration ice that are moving will leave a 5-day memory on every pixel they cross; for example, areas of part water and part moving ice, such as the Beaufort edges or ESS, will look like they have more open water than they really do. Similarly, if there are low concentration cloud artifacts, they will also be preserved for 5 days. Also, if new ice were forming, it would likewise not show up for 5 days; but no new ice is forming yet.

However, in my experience, the vast majority of artifacts in these maps are high concentration cloud artifacts, and using the minimum does well at removing most of those. If you follow the evolution of the ice edge this seems to do a good job and maybe hints at what might be coming, such as a continued edge retreat in the Beaufort (minus advection) and NW of the Laptev bite.

Maybe think of this map as something like a worst-case scenario. Use the originals (on the right) as a guide to aid interpretation.

Large file - click.

Except that the algorithm doesn’t know when the darkening is due to clouds or refreezing, in which late case the algorithm would be leading us to believe in the opposite direction of what would be coming.
In any case, it is an interesting approach.
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petm

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Re: The 2019 melting season
« Reply #5454 on: August 10, 2019, 06:17:57 PM »
Except that the algorithm doesn’t know when the darkening is due to clouds or refreezing, in which late case the algorithm would be leading us to believe in the opposite direction of what would be coming.
In any case, it is an interesting approach.

Yeah, that's one of the types of artifacts to be sure. During the freezing season, this approach definitely wouldn't be very useful.

petm

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Re: The 2019 melting season
« Reply #5455 on: August 10, 2019, 07:50:04 PM »
Fast ice coming off Komsomolets Island: https://go.nasa.gov/2ONtQdH .

Also serious melting in the last couple of days of the land ice on all of these Severnaya Islands: https://go.nasa.gov/2OOGg5e .
« Last Edit: August 10, 2019, 07:59:13 PM by petm »

sailor

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Re: The 2019 melting season
« Reply #5456 on: August 11, 2019, 12:52:01 AM »
Massive inflow of fire smoke today through the Laptev sea.
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Killian

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Re: The 2019 melting season
« Reply #5457 on: August 11, 2019, 05:19:56 AM »
Any thoughts on why these two are so similar, or on what, if anything, it tells us about the rest of the season?

Really unexpected.

Same for Charctic, by the way.

DrTskoul

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Re: The 2019 melting season
« Reply #5458 on: August 11, 2019, 05:38:05 AM »
Coincidink??

peterlvmeng

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Re: The 2019 melting season
« Reply #5459 on: August 11, 2019, 05:42:56 AM »
The turbulence mixing of SST is obvious due to cyclone in Beaufort Sea or Canadian Archipelago Area, East Siberia Sea and Laptev Sea from August 8th-10th this year. The turbulence mixing will lower the high SST and increase the low SST to narrow the temperature discrepency of different region in principle. However, the reality is the high SST region do not drop much while the low SST increase a lot indicating strong warm mixing layer of upper sea surface. The Ekman pumping is strong to maintain the high SST. Especially in the Laptev sea, the huge amount of heat accumulation is real problem for the ice of Atlantic side.
« Last Edit: August 11, 2019, 05:27:39 PM by peterlvmeng »

Often Distant

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Re: The 2019 melting season
« Reply #5460 on: August 11, 2019, 07:16:06 AM »
Ice shines through cross cloud and smoke. Hanging in there. Holding back a future SST increase

Often Distant

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Re: The 2019 melting season
« Reply #5461 on: August 11, 2019, 09:30:04 AM »
An ESS flow roughly measuring 1700m by 1400m, near 80km offshore.
But a blurry speck on worldview, bracing for disintegration.
I would guess the smallest blurry specks appearing here would measure single digit meters.

aslan

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Re: The 2019 melting season
« Reply #5462 on: August 11, 2019, 09:35:43 AM »
As an illustration of the growing importance of the convection for Arctic : https://mobile.twitter.com/Climatologist49/status/1160400333601832960

And on this GFS was not too bad (I did not look at IFS). Not yet to the point where subtropical storms Can be, but we are on the good way  :D

Lord M Vader

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Re: The 2019 melting season
« Reply #5463 on: August 11, 2019, 09:48:17 AM »
Latest EC op run is a disaster for the ice. The thicker ice at the Atlantic side will be flushed out right into the the toilet, e.g big ice export. While the externt numbers might not be too influenced by this weather, the volume numbers should take a serious hit.

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Re: The 2019 melting season
« Reply #5464 on: August 11, 2019, 12:42:55 PM »
Any thoughts on why these two are so similar, or on what, if anything, it tells us about the rest of the season?

Really unexpected.

Same for Charctic, by the way.

Same reason for this one, I think.

be cause

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Re: The 2019 melting season
« Reply #5465 on: August 11, 2019, 01:29:10 PM »
beautiful :) .. b.c.
2007 + 5 = 2012 + 4 = 2016 + 3 = 2019 + 2 = 2021 
 (phew)

Mark Tough

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Re: The 2019 melting season
« Reply #5466 on: August 11, 2019, 01:39:15 PM »
Ok! Super long time since last post but so perfect...nothing further needed  ;)

FishOutofWater

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Re: The 2019 melting season
« Reply #5467 on: August 11, 2019, 01:56:21 PM »
I've always hated margarine.

Early heat is necessary to have a strong melt year. That's what's going on with the pretty similar curves. The rest is either coincidence or a function of the geography of the Arctic and surrounding seas. Geographical controls are important to the evolution of the melt season.

El Cid

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Re: The 2019 melting season
« Reply #5468 on: August 11, 2019, 02:34:02 PM »
latest ecmwf run gives a final chance for 2019 to get the gold medal: lots of warm air coming from Asia - don't know it it will be enough

DrTskoul

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Re: The 2019 melting season
« Reply #5469 on: August 11, 2019, 02:42:55 PM »
latest ecmwf run gives a final chance for 2019 to get the gold medal: lots of warm air coming from Asia - don't know it it will be enough

Margarine Arctic ice, meet heat...

DavidR

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Re: The 2019 melting season
« Reply #5470 on: August 11, 2019, 02:48:17 PM »
NSIDC for the 10 th puts sea ice extent at 5.093 M km^2 a drop of 166K km^2. 

Lowest on record!!!  2012 was lowest for just 2 days!.

2012 has lost its big chance to pull away and now its going to be a nail biting ride to the finish.
« Last Edit: August 11, 2019, 03:22:28 PM by DavidR »
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Killian

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Re: The 2019 melting season
« Reply #5471 on: August 11, 2019, 05:01:56 PM »
NSIDC for the 10 th puts sea ice extent at 5.093 M km^2 a drop of 166K km^2. 

Lowest on record!!!  2012 was lowest for just 2 days!.

2012 has lost its big chance to pull away and now its going to be a nail biting ride to the finish.

I don't understand. Looking at the Charctic chart 2012 hasn't been the lowest for some time.

EDIT: Ah. You're looking at daily, not 5-Day.
« Last Edit: August 11, 2019, 05:55:33 PM by Killian »

grixm

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Re: The 2019 melting season
« Reply #5472 on: August 11, 2019, 05:04:45 PM »
NSIDC for the 10 th puts sea ice extent at 5.093 M km^2 a drop of 166K km^2. 

Lowest on record!!!  2012 was lowest for just 2 days!.

2012 has lost its big chance to pull away and now its going to be a nail biting ride to the finish.

I don't understand. Looking at the Charctic chart 2012 hasn't been the lowest for some time.

Charctic uses 5-day averages. On daily values posted in the area and extent data thread it was lowest.

grixm

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Re: The 2019 melting season
« Reply #5473 on: August 11, 2019, 05:09:19 PM »
You can see the effect of the blowtorch on the asian side on the island ice caps. Melting like crazy compared to 4 days ago.

uniquorn

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Re: The 2019 melting season
« Reply #5474 on: August 11, 2019, 05:11:28 PM »
The turbulence mixing of SST<>
Good idea but wouldn't it be better to use SST rather than the anomaly?
Using anomalies introduces a comparison with previous year's ice cover that probably isn't related to mixing this year.

peterlvmeng

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Re: The 2019 melting season
« Reply #5475 on: August 11, 2019, 05:25:01 PM »
The turbulence mixing of SST<>
Good idea but wouldn't it be better to use SST rather than the anomaly?
Using anomalies introduces a comparison with previous year's ice cover that probably isn't related to mixing this year.
Yes, of course, uniquorn. It is more appropriate to use actual SST. But the original SST map do not have such strong color difference compared with anomaly map. The anomaly map ranges from August 8th-10th this year. Thanks for your suggestion.

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Re: The 2019 melting season
« Reply #5477 on: August 11, 2019, 07:05:32 PM »
Interesting to see gaps in the ice showing up in worldview as far north as 89N. The attached link is to an area of cloud free ice from 150W to 150E (due north from Barrow to the ESS/Laptev border) and from about 88-89N (100-200km from the pole.)
It's in a terrible state all the way to the Pole. Yesterday's imagery shows it well, no fancy channel-fiddling needed!

https://worldview.earthdata.nasa.gov/?v=-306950.4643315668,-193208.65791401532,348409.5356684332,146247.34208598468&p=arctic&t=2019-08-10-T16%3A00%3A00Z&l=VIIRS_SNPP_CorrectedReflectance_TrueColor(hidden),MODIS_Aqua_CorrectedReflectance_TrueColor(hidden),MODIS_Terra_CorrectedReflectance_TrueColor,Reference_Labels(hidden),Reference_Features(hidden),Coastlines

petm

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Re: The 2019 melting season
« Reply #5478 on: August 11, 2019, 07:23:13 PM »
Very striking and rapid changes indeed in the Laptev sector, at the edge and extending far into the pack. The forecast suggests that it may continue for a few more days.

https://go.nasa.gov/2ORvvPE

aslan

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Re: The 2019 melting season
« Reply #5479 on: August 11, 2019, 07:44:19 PM »
As an illustration of the growing importance of the convection for Arctic : https://mobile.twitter.com/Climatologist49/status/1160400333601832960

And on this GFS was not too bad (I did not look at IFS). Not yet to the point where subtropical storms Can be, but we are on the good way  :D

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

It was probably mid level thunderstorms, starting from around 750 hPa. Strong shear and vorticity at this level probably help the convection. Sat pictures is showing top CBs down to -50° to -60°, which means a slight overshot, up to 250 hPa. In this case, surface conditions (i.e. batshit crazy SSTs) were not a direct factor. CBs starts in the warm air advection associated with a low centered around 84°N 135°E. But the WAA was extreme, with temperature above 10°C at 850 hPa in the ribbon of max temperature. CBs were probably on the western flank of thiw WAA, and not directly linked to the front to the North, stretching from the low over Barents to the aforementioned low. It is also likely the most northern strike detected.

P.S. : WAA can also - in this case - be traced with smokes. Coming from Taymyr peninsula in the morning (UTC time) of the 10th, and advected towards Laptev Sea on the 11th. Between the two pictures, on the western flank of the advection, something happened...
« Last Edit: August 11, 2019, 07:53:01 PM by aslan »

oren

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Re: The 2019 melting season
« Reply #5480 on: August 11, 2019, 08:07:58 PM »
Interesting to see gaps in the ice showing up in worldview as far north as 89N. The attached link is to an area of cloud free ice from 150W to 150E (due north from Barrow to the ESS/Laptev border) and from about 88-89N (100-200km from the pole.)
It's in a terrible state all the way to the Pole. Yesterday's imagery shows it well, no fancy channel-fiddling needed!
To remind the forum, all the ice from Laptev to the pole is just first year ice, following the continuous transpolar drift over the winter and spring, as shown in A-Team's Ascat animations. So this ice is quite vulnerable, and may still spring some surprise before the end of the season.
« Last Edit: August 11, 2019, 10:11:29 PM by oren »

El Cid

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Re: The 2019 melting season
« Reply #5481 on: August 11, 2019, 08:21:52 PM »
You might be right oren, but I think it is now too late. We have 2-3-4 weeks left only for real melt.

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Re: The 2019 melting season
« Reply #5482 on: August 11, 2019, 08:27:32 PM »
You can see the effect of the blowtorch on the asian side on the island ice caps. Melting like crazy compared to 4 days ago.

Indeed!

A little further south, 05.08 vs 11.08.
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Freegrass

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Re: The 2019 melting season
« Reply #5483 on: August 11, 2019, 08:33:54 PM »
Interesting to see gaps in the ice showing up in worldview as far north as 89N.
It'll be 6°C at the pole in a few days from now @ 850 hPa, and the wind forecast for the coming days has picked up again compared to yesterday's forecast. All sides of the ice are getting hammered, while rainstorms keep lining up.

Also a lot of sun is hitting the open water in the ESS, while winds stir up the upper layers of the ocean on the ice edges. I think all this heat entering the arctic is actually much worse for the ice at the end of a melting season than a GAC, no? While a GAC may help break records, high pressure systems and heat just before things start freezing up again is much worse for the ice in the long run, no? Am I presuming this correctly?
« Last Edit: August 11, 2019, 08:40:36 PM by Freegrass »
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Freegrass

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Re: The 2019 melting season
« Reply #5484 on: August 11, 2019, 09:28:54 PM »
This ice has been hammered by high pressure for many weeks now, and it looks like it's in really bad shape. I don't see how all this can survive the high temperatures of the coming week. The surface temperature at this moment is 3.5°C.

https://go.nasa.gov/2OOIYYh
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jdallen

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Re: The 2019 melting season
« Reply #5485 on: August 11, 2019, 09:35:03 PM »
NSIDC for the 10 th puts sea ice extent at 5.093 M km^2 a drop of 166K km^2. 

Lowest on record!!!  2012 was lowest for just 2 days!.

2012 has lost its big chance to pull away and now its going to be a nail biting ride to the finish.

I don't understand. Looking at the Charctic chart 2012 hasn't been the lowest for some time.

Charctic uses 5-day averages. On daily values posted in the area and extent data thread it was lowest.

Mean while, pulling this thread over from there, considering JAXA:

NSIDC Total Area as at 9 August 2019 (5 day trailing average)  3,570,381 km2

This melt season is riveting. I think we have still not fully understood what a dramatically cloudier, wetter Arctic will behave like. Your observations about the current circulation and weather conditions is the right question to ask. I have none of the answers.

With all of the early open water and heat uptake, combined with the new cloudier Arctic holding that heat in, it would not surprise me if we have ridiculously warm autumn temps and a very slow refreeze.
With all due respect, there's nothing counter intuitive between the current weather and the extent drop.
FooW explained it very well a few days ago: warmth and compaction over Laptev and ESS, a cyclone messing up Beaufort, and continued heat in CAA
It's not the extent drop; it's the *lack* of extent and (particularly) area drop under what appear to be good melt conditions I'm wondering at.
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jdallen

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Re: The 2019 melting season
« Reply #5486 on: August 11, 2019, 09:39:06 PM »
Interesting to see gaps in the ice showing up in worldview as far north as 89N. The attached link is to an area of cloud free ice from 150W to 150E (due north from Barrow to the ESS/Laptev border) and from about 88-89N (100-200km from the pole.)
It's in a terrible state all the way to the Pole. Yesterday's imagery shows it well, no fancy channel-fiddling needed!

https://worldview.earthdata.nasa.gov/?v=-306950.4643315668,-193208.65791401532,348409.5356684332,146247.34208598468&p=arctic&t=2019-08-10-T16%3A00%3A00Z&l=VIIRS_SNPP_CorrectedReflectance_TrueColor(hidden),MODIS_Aqua_CorrectedReflectance_TrueColor(hidden),MODIS_Terra_CorrectedReflectance_TrueColor,Reference_Labels(hidden),Reference_Features(hidden),Coastlines
Meanwhile, same date in 2013 we have this what's shown below.  I'm not sure the state of the ice at the pole will be indicative of outcome.
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Re: The 2019 melting season
« Reply #5487 on: August 11, 2019, 09:46:35 PM »
...
It's not the extent drop; it's the *lack* of extent and (particularly) area drop under what appear to be good melt conditions I'm wondering at.
And I repeat what I have replied over there. Concurrent with these conditions permitting a continuous extent drop, it's been cold over the Pacific edge, from ESS-CAB to Beaufort, leading to a ice surface refreezing (not ocean refreezing), very visible if you browse AMSR2 Bremen maps in the last few days, and coinciding with the brake in Area (not extent) that Gerontocrat reports latest days. Evidence: look at the goddamn charts.

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Re: The 2019 melting season
« Reply #5488 on: August 11, 2019, 09:48:06 PM »
This ice has been hammered by high pressure for many weeks now, and it looks like it's in really bad shape. I don't see how all this can survive the high temperatures of the coming week. The surface temperature at this moment is 3.5°C.
The actual heat that can be transferred at this point I don't think overall will make that much of a difference.  Unless there's a lot of moisture in the advection, the heat content of the air is insufficient by itself to cause a lot of melt.

As insolation above 80 now is *also* starting to drop off rapidly that leaves just that heat already captured in the upper layers of ocean to do the work.

To that point, I think the danger to the pack right now is less the direct heat being delivered by advection, and more that it will interfere with the exchange balance, preventing loss to start from the ocean out of the atmosphere.

So, two $64 questions - how much heat has been captured, and how much of it will get pulled to the surface?
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Re: The 2019 melting season
« Reply #5489 on: August 11, 2019, 09:55:10 PM »
Ah...2013! I remember that configuration around the Pole. I remember also that the former 1,8 Mkm2 'safe-haven' north of the CAA/Greenland was still intact those days.
It is not, these days. All of the CAB-pack has lost it's integrity; most extent is debris.

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Re: The 2019 melting season
« Reply #5490 on: August 11, 2019, 10:00:47 PM »
And I repeat what I have replied over there. Concurrent with these conditions permitting a continuous extent drop, it's been cold over the Pacific edge, from ESS-CAB to Beaufort, leading to a ice surface refreezing

The willful ignorance of some posters is truly astounding.

Multiple posters explained to Sterk on the other thread he derailed that the refreezing he sees on the models is an artifact caused by clouds. Do you think he went to verify? Nope.

You will never see Conservatives apologize for being wrong. Never.

Mleary01

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Re: The 2019 melting season
« Reply #5491 on: August 11, 2019, 10:06:09 PM »
Dear Abby  (for those not in the know, she was for decades an advice columnists in the US) … Woops, wrong thread …  :-[
Hello everybody, I've decided to join this forum after many years of daily lurking and reading! :)
...
Mleary claims to have been reading our wisdom (and, uh, other postings) for "many years".  So why all the advice giving?  :o  I'll just guess he already has each of us pegged!  :P

And welcome, Mleary, to our varying degrees of dysfunction.   ;)

Thank you Tor :) I certainly enjoy reading the arguments (debate) and arguments (literally) and have learned a lot from this forum over that time. It's like being in the pub talking about football, atm, this season looks for a second place finish....unless the highly unpredicatble weather turns out something later this month. A bit like the Premier League  ;D

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Re: The 2019 melting season
« Reply #5492 on: August 11, 2019, 10:19:04 PM »
And I repeat what I have replied over there. Concurrent with these conditions permitting a continuous extent drop, it's been cold over the Pacific edge, from ESS-CAB to Beaufort, leading to a ice surface refreezing

The willful ignorance of some posters is truly astounding.

Multiple posters explained to Sterk on the other thread he derailed that the refreezing he sees on the models is an artifact caused by clouds. Do you think he went to verify? Nope.

You will never see Conservatives apologize for being wrong. Never.
This is 4 aug vs 9 aug ( no arctifact due to weather ).
Then go visit the other thread and check how much has area gone down vs extent
Wilful ignorance? I hope not, but this is pretty clear to me.
There is surface refreezing at the level of several 100,000 km2 for compactness to increase without strong winds (until yesterday).
« Last Edit: August 11, 2019, 10:35:28 PM by Sterks »

Sterks

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Re: The 2019 melting season
« Reply #5493 on: August 11, 2019, 10:25:58 PM »
And I repeat what I have replied over there. Concurrent with these conditions permitting a continuous extent drop, it's been cold over the Pacific edge, from ESS-CAB to Beaufort, leading to a ice surface refreezing

The willful ignorance of some posters is truly astounding.

Multiple posters explained to Sterk on the other thread he derailed that the refreezing he sees on the models is an artifact caused by clouds. Do you think he went to verify? Nope.

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Freegrass

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Re: The 2019 melting season
« Reply #5494 on: August 11, 2019, 10:51:30 PM »
This ice has been hammered by high pressure for many weeks now, and it looks like it's in really bad shape. I don't see how all this can survive the high temperatures of the coming week. The surface temperature at this moment is 3.5°C.
The heat content of the air is insufficient by itself to cause a lot of melt.
The determining factor here will be the wind, no? I think that warm moist air blowing on wet ice should cause a lot of melt...

Quote
To that point, I think the danger to the pack right now is less the direct heat being delivered by advection, and more that it will interfere with the exchange balance, preventing loss to start from the ocean out of the atmosphere.
I completely agree with that. Cyclones extract heat from the ocean, right? That's what happens with hurricanes if I remember correctly.

I found a new toy to explore the ice under the clouds. Look at how much the ice pack has shrunk in the last 24 48 hours...  ???
https://go.nasa.gov/2ORSOZt
(Set opacity to preference)
« Last Edit: August 12, 2019, 01:55:09 AM by Freegrass »
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Sterks

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Re: The 2019 melting season
« Reply #5495 on: August 11, 2019, 11:13:39 PM »
This week, while the pacific edge was being severely affected by the GAC in 2012, it has been an immobile and relatively cold week for this edge in 2019. Extent has continued dropping but note that 2012 started higher in extent.

Next week (and following) is the one where 2019 won’t really follow the pace of 2012 anymore. Next week, however, melting will show a vigorous pace for the time of the year given the forecasted weather.

TeaPotty

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Re: The 2019 melting season
« Reply #5496 on: August 11, 2019, 11:22:32 PM »
<snip, keep this nonsense out of this thread, for Pete's sake; N.>
« Last Edit: August 12, 2019, 04:03:17 PM by Neven »

petm

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Re: The 2019 melting season
« Reply #5497 on: August 11, 2019, 11:25:18 PM »
Depending on various factors including how much scientific training one has, what strikes one person as obvious may be difficult to understand for another. In science, it's almost never easy to get an instrument to measure exactly what you want.

Case in point: Sea ice concentration. Some of the best instruments are on the AMSR-E/2 satellites. Due to physics, data from the high frequency channel, which is used as input to sea ice concentration algorithms, is sensitive to water vapor and clouds. One result of this is that the Bremen concentration maps typically show high concentration ice in areas covered by cloud, regardless of the actual ice concentration.

In fact, even without knowing any technical details, it's easy to see this effect by looking at consecutive days, e.g. using gifs. Large obvious cloud artifacts (purple in the NIC color scheme) frequently appear. These artifacts typically don't persist for many days (except some areas do remain cloudy for weeks on end) and are not predictive of ice edge changes. E.g. Look at the righthand map on the gifs in this post.

In short: Bremen concentration maps from a cloudy days are almost useless. The most recent one (Aug. 10) is a good example. I've attached a fade-across gif of Aug. 9 to 10; originals, right; 5-day median, left. The huge purple area that suddenly covers (e.g.) the asian side is obviously due to cloud. If you have any doubts, cross reference the satellite images, also attached (ice under clear sky is dark red).

I.e., It is counter-productive to cherry-pick cloudy days in an attempt to show concentration increases (or similarly, area).

Click to animate top gif.
« Last Edit: August 11, 2019, 11:41:09 PM by petm »

Sterks

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Re: The 2019 melting season
« Reply #5498 on: August 11, 2019, 11:40:22 PM »


If you notice, a few posts above I have used August 9 map, instead of August 10 map. It does not matter. From my point of view, it is clear that there's surface refreezing along the entire Pacific Edge.

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.

For me it is clear that, after so many weeks of activity, this last week the edge has remained immobile, relatively cold and inactive for the most part (bottom melting continuing obviously). While in 2019 it was really affected by GAC.

All kinds of creatures lurk wanting to have a 2012 repeat, some of the most disgusting ones quit lurking. I think not repeat of 2012.

petm

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Re: The 2019 melting season
« Reply #5499 on: August 11, 2019, 11:55:08 PM »
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.

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For me it is clear that, after so many weeks of activity, this last week the edge has remained immobile, relatively cold and inactive for the most part (bottom melting continuing obviously). While in 2019 it was really affected by GAC. <snip> I think not repeat of 2012.

Maybe. I too have thought for a while that the impact of the GAC was underrated here by some. But I think it's still too soon to tell. In a week or two we will know. Certainly the weather seems to be cooperating in terms of comparing storms to not.
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