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magnamentis

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Re: The 2019 melting season
« Reply #600 on: April 27, 2019, 08:24:49 PM »
Could you help me understand the difference between "area" and "extent"? I thought they were the same thing...millions of square kilometers?

plenty of info available here:

https://bit.ly/2Pwx2ax

sark

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Re: The 2019 melting season
« Reply #601 on: April 28, 2019, 07:33:19 AM »
Long range ensembles expect another one of these high pressure blocks to flit straight from the equator to pole at high speed, potentially colliding with the remaining high pressure block from the current mess.   From the Laptev. 

Why are these blocks coming from both sides of the planet and colliding in the Arctic?  Is that typical?
« Last Edit: April 28, 2019, 08:17:25 AM by sark »

Niall Dollard

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Re: The 2019 melting season
« Reply #602 on: April 28, 2019, 10:48:31 AM »
Why are these blocks coming from both sides of the planet and colliding in the Arctic?  Is that typical?

Formation of  a high pressure at the pole is typical. This forecast chart for 6th May shows HP centred around the pole with typical polar easterlies circulating around.

This helps to block out both Atlantic and Pacific incursions. The surface temps show a cooler ring between 70N and 80N (after the warm incursion from the Pacific has dissipated).

What would be bad for the ice is for this area of HP to slide back over the CAA and with LP over north Asia allowing another Pacific incursion. 

That said, in a few weeks we will soon be moving into high summer (June/July period) when Arctic HP can have the opposite effect on the ice and clear skies and high insolation can allow for considerable melting.
   

sark

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Re: The 2019 melting season
« Reply #603 on: April 28, 2019, 10:19:32 PM »
I see it.  I also see how much cold is being lost in the next 2 weeks.

What I'm asking specifically for is if it seems normal during the spring PV transition for high pressure to move rapidly from equator to pole without so much as half a trip around the world?  Nevermind from both East and West at the same time.  Are we okay?

Niall Dollard

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Re: The 2019 melting season
« Reply #604 on: April 29, 2019, 01:22:44 AM »
No. We are not ok. There is plenty of research out there highlighting the expansion of the hadley cells. Add to that the broadening of the Ferell cells northward and collapse of the polar.

All to be expected from the rise in global temperature.

All eyes on this summer then. Will we see another cloudy LP dominated one ? Is this the new pattern for the shrinking Arctic. Or will we see another summer period like 2012 when it all went wrong ?

Slim

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Re: The 2019 melting season
« Reply #605 on: April 29, 2019, 02:28:51 AM »
I see it.  I also see how much cold is being lost in the next 2 weeks.

What I'm asking specifically for is if it seems normal during the spring PV transition for high pressure to move rapidly from equator to pole without so much as half a trip around the world?  Nevermind from both East and West at the same time.  Are we okay?

I'm a long time lurker here, probably for more than 5 years. Just decided to post now, great forum. Just a question though from someone who is a total layman. Can cold actually be lost? When the cold air from the arctic is forced out into lower latitudes, does this actually change the equation at all or is all the heat/lack of heat in the system conserved in some way? Thanks.

<I've copied your question to this thread; N.>
« Last Edit: April 29, 2019, 10:33:50 AM by Neven »

sark

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Re: The 2019 melting season
« Reply #606 on: April 29, 2019, 05:57:51 AM »
Here's some background on the last season.  The first just shows that the Arctic warming has resulted in at least some occurrence of warm arctic, cold continents

The second is from 1948-2019, 500mb height, Feb 1 - April 25 composite mean

Third, temperatures at 1000mb, Jan 1 - April 25, 1969-2019

Finally, 500mb Anomaly, November 1 - April 25, 1960-2019

wdmn

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Re: The 2019 melting season
« Reply #607 on: April 29, 2019, 06:12:56 AM »
Thanks for posting these Sark. I find it very difficult to make much of them. There doesn't seem to be any discernible trend when presented in this form... Or am I missing something?

sark

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Re: The 2019 melting season
« Reply #608 on: April 29, 2019, 06:42:41 AM »
Thanks for posting these Sark. I find it very difficult to make much of them. There doesn't seem to be any discernible trend when presented in this form... Or am I missing something?

Pretty raw data.  After poring through them looking for patterns I think winter 2018-2019 looks like one of the cold ones.

Aluminium

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Re: The 2019 melting season
« Reply #609 on: April 29, 2019, 06:43:56 AM »
April 23-28.

The Lena wakes up on time.

wdmn

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Re: The 2019 melting season
« Reply #610 on: April 29, 2019, 07:05:48 AM »
Thanks for posting these Sark. I find it very difficult to make much of them. There doesn't seem to be any discernible trend when presented in this form... Or am I missing something?

Pretty raw data.  After poring through them looking for patterns I think winter 2018-2019 looks like one of the cold ones.

How do you connect this to your statement in your previous post that, "Arctic warming has resulted in at least some occurrence of warm arctic, cold continents"?

Is the problem that the information is presented at a scale/time frame that is useless? I wonder if looking at Jan 1 through March 15 would be more revealing?

sark

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Re: The 2019 melting season
« Reply #611 on: April 29, 2019, 08:55:06 AM »
How do you connect this to your statement in your previous post that, "Arctic warming has resulted in at least some occurrence of warm arctic, cold continents"?

Is the problem that the information is presented at a scale/time frame that is useless? I wonder if looking at Jan 1 through March 15 would be more revealing?

wdmn, here's that look...

I won't try to guess what it portends

wdmn

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Re: The 2019 melting season
« Reply #612 on: April 29, 2019, 09:08:17 AM »
Thanks a lot for doing that Sark. I was just musing, and didn't expect you to do it!

Still does not provide clarity for me either... but some recent years look like they have more pronounced differences using this time frame.

sark

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Re: The 2019 melting season
« Reply #613 on: April 29, 2019, 09:38:40 AM »
Thanks a lot for doing that Sark. I was just musing, and didn't expect you to do it!

Still does not provide clarity for me either... but some recent years look like they have more pronounced differences using this time frame.

Here's something a little more useful, perhaps.  A fun way to use this tool.  This is the 500mb anomaly running mean.  I took about a 25 day chunk of time across recent months, this is the resulting 500mb anomaly vs ESRL's climo

oren

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Re: The 2019 melting season
« Reply #614 on: April 29, 2019, 10:04:09 AM »
April 23-28.

The Lena wakes up on time.
Renewed signs of general movement from Chukchi to the Barents. This is what I fear the most, especially considering the forecasts for a dipole-like setup in the next few days. The longer the movement continues without change the thicker the ice that gets exported and lost.

El Cid

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Re: The 2019 melting season
« Reply #615 on: April 29, 2019, 10:08:24 AM »
RE: sark: warm arctic, cold continents.

As your gifs move a bit too fast, I attach mine instead: 2016-19 winters vs 1960-90. No sign of warm arctic/cold continents, instead: very warm arctic and quite warm continents.

Also: on your charts we can see that instead of a big cold airmass we are increasingly getting two smaller "poles of cold": one in Greenland/N.Canada and one in Siberia

Neven

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Re: The 2019 melting season
« Reply #616 on: April 29, 2019, 10:41:56 AM »
something tells me we're in for a nasty drop from day 2-5

Looks like you were right, JAXA reported a 112K drop for the 28th.

Renewed signs of general movement from Chukchi to the Barents. This is what I fear the most, especially considering the forecasts for a dipole-like setup in the next few days. The longer the movement continues without change the thicker the ice that gets exported and lost.

I'll second that. The high pressure over the Beaufort just keeps going, and we're now entering May...
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b_lumenkraft

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Re: The 2019 melting season
« Reply #617 on: April 29, 2019, 11:21:03 AM »
I'm a long time lurker here, probably for more than 5 years. Just decided to post now

Hello and welcome Slim. :)

Dharma Rupa

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Re: The 2019 melting season
« Reply #618 on: April 29, 2019, 12:01:39 PM »
RE: sark: warm arctic, cold continents.

As your gifs move a bit too fast, I attach mine instead: 2016-19 winters vs 1960-90. No sign of warm arctic/cold continents, instead: very warm arctic and quite warm continents.

In WACC (or WACCy) the Cold is in comparison to the Warm, not to an absolute, so warm Arctic and quite warm continents is WACCy as long as the continents are warming more slowly than the Arctic.

El Cid

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Re: The 2019 melting season
« Reply #619 on: April 29, 2019, 01:14:35 PM »
RE: sark: warm arctic, cold continents.

As your gifs move a bit too fast, I attach mine instead: 2016-19 winters vs 1960-90. No sign of warm arctic/cold continents, instead: very warm arctic and quite warm continents.

In WACC (or WACCy) the Cold is in comparison to the Warm, not to an absolute, so warm Arctic and quite warm continents is WACCy as long as the continents are warming more slowly than the Arctic.

Does it really mean that? As far as I know, it means that due to Arctic winter warming, the polar jet gets "curvy" and frequent cold intrusions happen to lower latitudes, bringing sometimes bitterly cold winters, see eg here:

https://agupubs.onlinelibrary.wiley.com/doi/full/10.1002/2016GL069024

"Coinciding with the continued Arctic sea ice loss and Arctic amplification, cold winters and cold waves have recently been observed to be more frequent and severe over Europe, Central Asia, and the eastern United States".

I know it is a bit OT but as we move towards a more equable climate it can not happen any other way than arctic warming > midlatitude warming > equatorial warming. And this is indeed what is happening.

bbr2314

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Re: The 2019 melting season
« Reply #620 on: April 29, 2019, 04:23:46 PM »
Beyond the enduring polar heat of the next week or so, the next event to watch (IMO) is the +500MB pulse incoming from Central Asia in sync with the developing cyclone in the Indian Ocean (either coincident, responsible, or both for the +500MB pulse). This can be seen dominating most of northwest Siberia by D10 on the 00z EURO but I wonder if it will end up drifting into the Arctic.

The below map is +144 hours and the +500MB area is over Kazakhstan/ish here, and the Indian Ocean cyclone is also visible.



If this heads more towards the Arctic and lingers less in Siberia, it could result in a continuation or worsening of impending conditions, and it must also be noted new +500MB blocking also appears in force in the NE PAC by D10 on the 00z EURO as well. There may only be a brief respite from the short-medium range +0C temps before many areas face similar conditions once more.

magnamentis

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Re: The 2019 melting season
« Reply #621 on: April 29, 2019, 09:38:11 PM »
if the atlantic ocean is warm enough to obliterate most of what's coming down (south) we could even see a double-century drop in one of the next 3 days. as we know most of the bering and parts of the chucky were ice-free a few weeks ago, hence it must be very poor ice there and if that's indeed the case, waves and temps around +5C could simply kill one huge chunk of ice off these days and that would make the above mentioned happen.

i generally think that the ever thinner and more fragmented ice will sooner or later lead to unprecedented fluctuations (drops) in ice extent, meaning drops of over 300'000 km2 in one day.

i'm not saying it will but i see a possibility that we shall go into uncharted "waters" in respect to melting speeds in spring as well as refreezing speeds in late fall.

uniquorn

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Re: The 2019 melting season
« Reply #622 on: April 29, 2019, 10:46:00 PM »
Attempting here to locate the least mobile ice by highlighting those areas with the least change detected by ascat.
top left: ascat (contrast enhanced) day 68-118
top right: interferometry applied by creating frames of (R,G.B) = (dayn - dayn-1, dayn - dayn-2, dayn - dayn-3)
bottom left: edge detect applied to interferometry
bottom right: heavy contrast applied to edge detect to highlight least mobile areas.

edit:last chance to vote in the 'ice edge at minimum poll'
https://forum.arctic-sea-ice.net/index.php/topic,2632.msg194424.html#msg194424

« Last Edit: April 29, 2019, 10:59:36 PM by uniquorn »

b_lumenkraft

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Re: The 2019 melting season
« Reply #623 on: April 29, 2019, 10:55:44 PM »
The sparrowhawk forming.

Tom_Mazanec

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Re: The 2019 melting season
« Reply #624 on: April 29, 2019, 11:25:36 PM »
What's a 'sparrowhawk'?

GoSouthYoungins

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Re: The 2019 melting season
« Reply #625 on: April 29, 2019, 11:36:02 PM »

i generally think that the ever thinner and more fragmented ice will sooner or later lead to unprecedented fluctuations (drops) in ice extent, meaning drops of over 300'000 km2 in one day.


IMO this does seem likely. There have been many areas of mobile ice over the last month which has seen the open water freeze. The ice there is naturally very very thin.

As the insolation balance crosses the threshold in the next few weeks, the laptev sea could see this occur at a pretty large scale. It could also happen to a lesser degee in the beaufort and chukchi.

Meanwhile, the barents sea ice has been drifted south about 80 km in the past week. This has temporarily lead to increases in the seas extent and area, but this short term increase in ice will lead to a medium term decrease. The month of May will likely sea the barents go from 500k to 0k.


In general the ice is much more mobile than "ever" before. Other than fast ice around the edges of the arctic ocean, the only serious area of ice that seems able to stack up faster than it exports/melts is in the triangle north of the CAA and Greenland. This ice is found from Price Patrick to the North Pole to the northern tip of Greenland. Everything other than that is thin, weak, and mobile.
« Last Edit: April 29, 2019, 11:41:30 PM by GoSouthYoungins »
big time oops

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Re: The 2019 melting season
« Reply #626 on: April 30, 2019, 01:31:45 AM »
What's a 'sparrowhawk'?
In the ice edge at minimum topic they drew lines around what shape the remaining ice would take. some vaguely look like animals.

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Re: The 2019 melting season
« Reply #627 on: April 30, 2019, 01:46:36 AM »
What's a 'sparrowhawk'?
In the ice edge at minimum topic they drew lines around what shape the remaining ice would take. some vaguely look like animals.

I think it will look like a penguin.
big time oops

b_lumenkraft

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Re: The 2019 melting season
« Reply #628 on: April 30, 2019, 07:25:51 AM »
What's a 'sparrowhawk'?

For reference:

My pessimism in a picture.

Green (sparrowhawk) line.

Neven

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Re: The 2019 melting season
« Reply #629 on: April 30, 2019, 09:31:05 AM »
The massive shift towards the Atlantic continues for at least another week. Extent in the Barentsz has gone up a bit, unlike the Greenland Sea, but there's a limit to that compensation, as we're already witnessing, especially at this time of year. I also wonder whether that cyclone right over the Kara Sea in the next three days will have a marked effect on the sea ice there.

Right now, the big drops are obviously caused by Okhotsk, Bering and Chukchi, and it's just a matter of time when the Beaufort is going to join the party. It already looks like there's quite a bit of open water along the coast and between floes, but under a camouflage of fog/thin ice, keeping the trend line on the UH AMSR2 graph steady, whereas in 2016 the trend line had already started dropping.

A the bottom, there's an animation showing the situation on May 7th 2016 (a week from today) versus yesterday. Given the current forecast things should look a lot more similar next week.
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FishOutofWater

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Re: The 2019 melting season
« Reply #630 on: April 30, 2019, 02:17:25 PM »
This image does not show warm arctic cold continents. Excellent image, Sark.

It shows something far more important. It shows the impingement of warm Atlantic and Pacific water into the Arctic and the increasing amounts of ocean heat that are entering the Arctic atmosphere from the Arctic ocean itself as the ice thins. The cold weather persists where thick ice piles up north of the CAA and northern Canada is still cold. Even Siberia is being warmed by the Atlantification of the Siberian side of the Arctic.



Graphics for the 500mb heights and ice thickness would be best done for exactly the same time periods to visualize the relationships between retreating and thinning ice, surface temperatures, and changes in atmospheric circulation patterns. In the post above, the comparisons are apples vs oranges.

It's very clear to me that there has been a large increase in heat transfer from the Arctic ocean water to the atmosphere. We will reach a planetary tipping point when there's so little ice that winter cloudiness cuts total radiative heat loss from the Arctic. Then we can expect really weird things, perhaps like super polar lows in midwinter along the shores of Siberia.
« Last Edit: April 30, 2019, 02:32:48 PM by FishOutofWater »

bbr2314

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Re: The 2019 melting season
« Reply #631 on: April 30, 2019, 03:23:29 PM »
This image does not show warm arctic cold continents. Excellent image, Sark.

It shows something far more important. It shows the impingement of warm Atlantic and Pacific water into the Arctic and the increasing amounts of ocean heat that are entering the Arctic atmosphere from the Arctic ocean itself as the ice thins. The cold weather persists where thick ice piles up north of the CAA and northern Canada is still cold. Even Siberia is being warmed by the Atlantification of the Siberian side of the Arctic.



Graphics for the 500mb heights and ice thickness would be best done for exactly the same time periods to visualize the relationships between retreating and thinning ice, surface temperatures, and changes in atmospheric circulation patterns. In the post above, the comparisons are apples vs oranges.

It's very clear to me that there has been a large increase in heat transfer from the Arctic ocean water to the atmosphere. We will reach a planetary tipping point when there's so little ice that winter cloudiness cuts total radiative heat loss from the Arctic. Then we can expect really weird things, perhaps like super polar lows in midwinter along the shores of Siberia.
They will increasingly begin to appear everywhere (and particularly during fall and spring), IMO.

bbr2314

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Re: The 2019 melting season
« Reply #632 on: April 30, 2019, 03:32:19 PM »
The +500MB intrusion from the Indian Ocean cyclone is now unanimously entering the Arctic at D10 across all modeling (via the Kara). It is obviously D10 but this is a larger atmospheric event and probably has a bit more certainty than normal (like our current warm intrusion). Most importantly, the key ingredient is already fully-formed and on the table (the cyclone).







We will barely have a respite between the current episode and the impending movement of ^ into the High Arctic.

Thomas Barlow

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Re: The 2019 melting season
« Reply #633 on: April 30, 2019, 05:02:32 PM »
Why are these blocks coming from both sides of the planet and colliding in the Arctic?  Is that typical?
Check out the jetstream at 500 or 250hPa spinning up those high pressures are ground level. The atmosphere is always trying to reach equilibrium. If it ever does settle down, a more normalised (less wavy) jetstream will likely settle in further north than usual.
That's my uneducated guess anyway.

https://earth.nullschool.net/#current/wind/isobaric/500hPa/orthographic=-84.35,77.67,619/loc=144.764,86.131
« Last Edit: May 01, 2019, 02:27:25 PM by Thomas Barlow »

El Cid

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Re: The 2019 melting season
« Reply #634 on: April 30, 2019, 06:39:58 PM »
This image does not show warm arctic cold continents. Excellent image, Sark.

It shows something far more important. It shows the impingement of warm Atlantic and Pacific water into the Arctic and the increasing amounts of ocean heat that are entering the Arctic atmosphere from the Arctic ocean itself as the ice thins. The cold weather persists where thick ice piles up north of the CAA and northern Canada is still cold. Even Siberia is being warmed by the Atlantification of the Siberian side of the Arctic.



...Then we can expect really weird things, perhaps like super polar lows in midwinter along the shores of Siberia.

It seems that the final pole of cold is going to be the Greenland/N.Canada region. And I also believe that with an ever more open/cloudy Arctic Sea, the North will be ruled by a big low pressure system even during the winter (or at least Nov/Dec before it freezes over). Question is: how it would change atmospheric circulation in the midlatitudes? Any guesses?

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Re: The 2019 melting season
« Reply #635 on: April 30, 2019, 09:06:32 PM »
Well a bit off topic but as far as WACC is concerned, it's primarily Eurasia that's been the champion of the cold continent phenomena, fueled in part by increasing snow - which is to be expected in a warming climate.

The WACC phenomena with Eurasia as the focus may be short lived and it could be that we are seeing the more likely longer-term outcome begin to show itself. As sea ice significantly vanishes, the huge block of ice that is Greenland becomes a more enduring sink to anchor arctic cold closer to north american region. If so, then the jet becomes more prominently driven by the increased temp/pressure differential between surrounding warmer air and Greenland (including CAA). All of this would of course lead to more frequent splitting and/or degradation of the polar cell.
« Last Edit: April 30, 2019, 09:15:31 PM by Ice Shieldz »

uniquorn

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Re: The 2019 melting season
« Reply #636 on: April 30, 2019, 09:51:57 PM »
On the ice measurements from whoi itp103-110.
itp107 closest to Chukchi latest reading -0.625C   https://www.whoi.edu/page.do?pid=163096

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Re: The 2019 melting season
« Reply #637 on: May 01, 2019, 03:04:37 AM »
This was ECMWF's forecast for tomorrow from 7 days ago.  Pretty similar to the setup we're actually expecting tomorrow, with strong high pressure from the Beaufort coast to Greenland, and low pressure in the Kara Sea area. I know the models are often wrong, but they are also often right, at least out 7 days.

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Re: The 2019 melting season
« Reply #638 on: May 01, 2019, 05:45:07 AM »
The NASA Worldview images are stunning today (4/30/19). I don't think I have ever seen such clear skies over so much of the arctic on the same day this early in the season. 

PSA, if you don't keep a close eye on worldview, make sure to check it out today.  You can see the effects of the weather that everyone is talking about.  It is still very early in the season and things can change a lot!  But, right now the ice looks to be in trouble in many spots. 

Bbr is predicting a cyclone will come up through the Kara in a few days.  That happened last year about this time and it seemed to help the ice and change the direction of the melt season.  If it happens now, with the current state of the ice, the results might be different. 

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Re: The 2019 melting season
« Reply #639 on: May 01, 2019, 10:43:42 AM »
This image is based on yesterday's Modis image with bands 7-2-1 overlayed with the daytime ice surface temperature using a compressed palette. Yellow has been calibrated to around 273 K (with orange-red being warmer), so the idea is to an alternative indication of where surface melt is likely:

be cause

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Re: The 2019 melting season
« Reply #640 on: May 01, 2019, 11:10:52 AM »
This image is based on yesterday's Modis image with bands 7-2-1 overlayed with the daytime ice surface temperature using a compressed palette. Yellow has been calibrated to around 273 K (with orange-red being warmer), so the idea is to an alternative indication of where surface melt is likely:


.. does deep purple mean smoke on the water ? :) .. b.c.

 seriously though .. this is a useful image .. and gerontocat may appreciate another way of seeing Greenland burn ..
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uniquorn

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Re: The 2019 melting season
« Reply #641 on: May 01, 2019, 12:26:00 PM »
This image is based on yesterday's Modis image with bands 7-2-1 overlayed with the daytime ice surface temperature using a compressed palette. Yellow has been calibrated to around 273 K (with orange-red being warmer), so the idea is to an alternative indication of where surface melt is likely:
Thanks for this, useful in areas where there are no clouds.

JayW

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Re: The 2019 melting season
« Reply #642 on: May 01, 2019, 12:28:51 PM »
One week (~174 hours) movie, Pacific side.
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Re: The 2019 melting season
« Reply #643 on: May 01, 2019, 12:42:16 PM »
This image is based on yesterday's Modis image with bands 7-2-1 overlayed with the daytime ice surface temperature using a compressed palette. Yellow has been calibrated to around 273 K (with orange-red being warmer), so the idea is to an alternative indication of where surface melt is likely:
Thanks for this, useful in areas where there are no clouds.

In case there is any doubt, only the white areas are clouds. Light blue is ice at surface temperatures outside the compressed palette. Generally below around 268 K. They could in theory be above the highest temperature shown by the palette, but I set it to make sure that wouldn't be a (significant) issue.

Sterks

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Re: The 2019 melting season
« Reply #644 on: May 01, 2019, 03:38:01 PM »
NH snow extent has broken the negative tendency, Rutgers maps show now positive anomalies in vast extents of Western and Southern Russia.
Thin cover, may melt fast, but this is positive for the melting season if it shows persistence in May.
« Last Edit: May 01, 2019, 03:57:35 PM by Sterks »

Sterks

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Re: The 2019 melting season
« Reply #645 on: May 01, 2019, 04:23:03 PM »
Right now, the big drops are obviously caused by Okhotsk, Bering and Chukchi, and it's just a matter of time when the Beaufort is going to join the party. It already looks like there's quite a bit of open water along the coast and between floes, but under a camouflage of fog/thin ice, keeping the trend line on the UH AMSR2 graph steady, whereas in 2016 the trend line had already started dropping.
Yep, Beaufort extent is going to take a dip this very first week of May, and EC forecast of today makes the wind pattern away from the coast more persistent, almost until the 11th if we trusted that long range forecast.

magnamentis

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Re: The 2019 melting season
« Reply #646 on: May 01, 2019, 07:51:26 PM »
Yep, Beaufort extent is going to take a dip this very first week of May, and EC forecast of today makes the wind pattern away from the coast more persistent, almost until the 11th if we trusted that long range forecast.

and this time big parts won't re-freeze and open water at the edges (coasts) of the arctic oceans will definitely take in some insolation in serious.

Sterks

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Re: The 2019 melting season
« Reply #647 on: May 01, 2019, 09:04:27 PM »
The ice being flushed seems pretty thick, is breaking in quite big blocks before dissolving west of Svalbard.

magnamentis

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Re: The 2019 melting season
« Reply #648 on: May 01, 2019, 09:56:35 PM »
since i rarely see anything of this kind posted here i thought i bring to your attention
this great source where one can get the best overall impression about the state of the ice.
getting close to satellite photos with zero cloud scenarios, while of course it is not.

the screenshot shows not the full potential/size and any date can be chosen to compare
between years or any other time frame.

link to site:

https://kuroshio.eorc.jaxa.jp/JASMES/daily/polar/index.html?date=&prod=SIC&area=NP&sensor=MOD

of course there is an antarctic selection as well as many other parameters to choose from.
since some of you like to post images on a regular basis, choose size and area shown very
carefully, this might be something for you.
« Last Edit: May 01, 2019, 11:40:19 PM by magnamentis »

vox_mundi

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Re: The 2019 melting season
« Reply #649 on: May 01, 2019, 10:54:33 PM »
« Last Edit: May 01, 2019, 11:35:46 PM by vox_mundi »
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