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Arctic sea ice / Re: The 2019 melting season
« Last post by jdallen on Today at 12:33:16 AM »
Before everyone gets superexcited about low extent numbers, we must realize that 2019 is very much the same as 2018 in the (inner) seas that matter. The difference between the two is that 2018 had much bigger Okhotsk Sea extent but that is irrelevant as the Okhotsk melts out anyway. See attachment. So, basically 2018 was the same as 2019 at this point.

It is true though that Pacification is very obvious in the past two years as never in previous years have we seen such an open Bering. What it means for the final, September numbers is still anybody's guess. It did not really matter last year, it might matter this year.
I've been pondering along the same lines.  The Okhotsk is irrelevant to what will be happening in a few weeks. 

The Bering is another matter. It's unclear me what charge of increased heat it is carrying and how much of it will pass in to the Chukchi.

Over all, I see open water in the peripheral seas far more relevant to the refreeze, when they create a heatvreserve that slows freezing in the central seas.

Weather in the central basin, coastal Alaska and Siberia are now key.  How soon the rivers break up and when we see melt ponds is where things will hang in the balance.

The recent cooling has been hopeful and helpful, but I'm unsure if it is enough to check the momentum.

Early open water is important because of the increased heat the surface is going to absorb through insolation. If the peripheral seas become warmer, I'd expect there to be higher humidity air reaching the Arctic. Is that good or bad for the preservation of sea ice? More cloud, more heat advected from lower latitudes, but less sunlight.
Again,I think the effect is more important to the refreeze.  More moisture in summer is more neutral possibly leading to negative feedbacks by increasing albedo with clouds.  Phase changes  won't be as important as temperatures are already  close to freezing, unless we ate talking about tropical scale imports of moisture,but those won't be from peripheral seas.
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Arctic sea ice / Re: The 2019 melting season
« Last post by uniquorn on Today at 12:01:47 AM »
Worldview terra modis, amundsen gulf, apr10-19.
Worldview terra modis, amundsen gulf, apr18(or nearest) 2010-2019.
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Arctic sea ice / Re: The Rammb Slider Thread
« Last post by uniquorn on April 19, 2019, 11:29:40 PM »
Hoping that the slider might show evidence of the tides. Drift would appear to be largely wind driven once fractured at the moment but if the wind drops the tide may show itself.
edit: unfortunately I don't have the broadband vol to check the slider regularly (or width. gives me an idea for a new thread   ;)  Funny. Possible best format doesn't play for the OP)
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Arctic sea ice / Re: The Rammb Slider Thread
« Last post by johnm33 on April 19, 2019, 11:19:16 PM »
"Amundsen" that's timely I've been thinking the tides there are about to kick off opening up the coastal ice off Banks driving ice across to Alaska and firing up the gyre. Plus that format gives me the opportunity to loop and adjust speed.
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The forum / Re: Suggestions
« Last post by johnm33 on April 19, 2019, 10:58:32 PM »
There's a case to made for allowing high worth contributors to control/edit the threads they create and which they inform/maintain for the general good.
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Arctic sea ice / Re: The Rammb Slider Thread
« Last post by uniquorn on April 19, 2019, 10:54:58 PM »
Looking for something about Amundsen Gulf tides found this journal from 1986.

International Hydrographie  Review,  Monaco,  LXIII (2),  July  1986CANADIAN  ARCTIC  TIDE  MEASUREMENTTECHNIQUES  AND  RESULTSby  B.J.  TAIT,  S.T.  GRANT,  D.  St.-JACQUES  and  F.  STEPHENSON (*)
https://journals.lib.unb.ca/index.php/ihr/article/viewFile/23426/27201

Quote
The  tide  in  the  southern  Beaufort  Sea  and  in  Amundsen  Gulf  propagates counterclockwise  about  an  amphidromic  point  situated near the  southwest  corner of  Banks  I.  It  propagates  quickly  along  the  coast  from  Alaska  to  a  point approximately midway along the Tuktoyaktuk Peninsula where it slows significantly,  reaching  Sachs  Harbour (site  4,  Figure  2)  on  Banks  I. about  six  hours  later.  In Amundsen  Gulf the  tide  travels  east  into  Dolphin  and  Union  Strait  and  Prince Albert  Sound  and  northwest  into  Prince  of Wales  Strait.The  tidal  propagation  patterns  in  the  waterways  between  the  eastern  end  of Amundsen Gulf and the southern end of M’Clintock Channel are complex and not yet  well  defined.  Further field  surveys  are  planned  for these  areas.

First image is fig2 from the journal.
rammb animation was 5MB and very small. Enlarged 2x took it to 18MB. Converting to mp4 gets 384kB. (click to play)
ffmpeg -i rb2.gif -pix_fmt yuv420p -vf "scale=trunc(iw/2)*2:trunc(ih/2)*2" rb2.mp4
Worldview terra modis apr18 (or nearest) 2010-2019posted on melting season
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Antarctica / Re: Ice Apocalypse - MULTIPLE METERS SEA LEVEL RISE (narrated video)
« Last post by AbruptSLR on April 19, 2019, 10:14:28 PM »
Reply #256 indicates that an increase in Agulhas leakage (see the attached image) contributes to a slowing down of the AMOC (which increased climate sensitivity); and the linked reference confirms that Agulhas leakage is projected to increase with continued anthropogenic global warming:

Tim, N., Zorita, E., Emeis, K.-C., Schwarzkopf, F. U., Biastoch, A., and Hünicke, B.: Influence of position and strength of westerlies and trades on Agulhas leakage and South Benguela Upwelling, Earth Syst. Dynam. Discuss., https://doi.org/10.5194/esd-2019-16, in review, 2019.

https://www.earth-syst-dynam-discuss.net/esd-2019-16/

Abstract. The westerlies and trade winds over the South Atlantic and Indian Ocean are important drivers of the regional oceanography around Southern Africa, including features such as the Agulhas current, the Agulhas leakage and the Benguela upwelling. The Agulhas leakage is the transport of warm and saline water from the Indian Ocean into the South Atlantic. The leakage is stronger during intensified westerlies and probably also when the wind systems are shifted poleward. Here we analyzed the wind stress of different observational and modelled atmospheric data sets (covering the last two millennia, the recent decades and the 21st century) with regard to the intensity and position of the south-easterly trades and the westerlies. The analysis reveals that variations of both wind systems go hand in hand. A poleward shift and intensification of westerlies and trades took place during the recent decades. Furthermore, the upwelling in South Benguela slightly intensified and the characteristics of the water masses fed into the upwelling region changed with a poleward shift of the trades. Projections for strength and position of the westerlies in the 21st century depend on assumed CO2 emissions. In the strongest emission scenario a further southward displacement will occur, whereas a northward shift is modelled in the weakest emission scenario, possibly due to the dominating driving effect of ozone recovery. Thus, the Agulhas leakage has intensified during the last decades and is projected to increase if greenhouse gas emission are not reduced. This will have a small impact on Benguela upwelling strength, but will have consequences for water mass characteristics in the upwelling region. An increased contribution of Agulhas water to the upwelling feed water masses will import more preformed nutrients and oxygen into the upwelling region.
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The rest / Re: Climate change activists should not fly
« Last post by Neven on April 19, 2019, 09:26:01 PM »
That's not true either, but if you don't like it here, you can go find another forum. There are millions out there.
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The rest / Re: The Empire vs Venezuela - News and History
« Last post by sidd on April 19, 2019, 09:25:46 PM »
Rosneft shields PDVSA from US sanctions:

"PDVSA has started passing invoices from its oil sales to Rosneft. "

"shipments in April to Reliance - owner of the world’s biggest refining complex – would be settled via Rosneft. "

"Reliance’s joint chief financial officer, told reporters on Thursday it was buying Venezuelan oil via Russian and also Chinese companies."

https://uk.reuters.com/article/us-venezuela-politics-rosneft-exclusive/exclusive-venezuela-skirts-u-s-sanctions-by-funneling-oil-sales-via-russia-idUKKCN1RU2A4

Ambani (reliance chief) has decided the the USA can be ignored.The reach of Empire now exceeds its grasp.

sidd
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Policy and solutions / Re: Tesla glory/failure
« Last post by Sigmetnow on April 19, 2019, 09:24:03 PM »
Article compares hardware, software/data, regulator acceptance, and market share outlook of the major competitors. 
From Seeking Alpha!

Tesla's Autopilot: Their Most Lucrative Asset - Tesla, Inc. 
https://seekingalpha.com/article/4254694-teslas-autopilot-lucrative-asset
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