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Sebastian Jones

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3350 on: June 25, 2020, 05:44:13 PM »
My apologies everyone.
Of course the melting down of nuclear power plants, unless they were to detonate like a nuclear bomb, would not trigger a nuclear winter.

I clearly confused "Stupid" questions with dumb answers.

I shall not do that again.

KenB

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3351 on: June 26, 2020, 02:49:53 AM »
[Moved here from "The 2020 Melting Season" thread]

I asked:  Hi Folks,
  ...why is it that the ice is thickest immediately north of the CAA?  Has this always been the case or is it a recent development?  Thanks! 

Oren replied:  Welcome KenB. This fits better in the questions thread but the basic answer is yes, it's "always" been the case, there is a general drift from the direction of Siberia towards CAA/Greenland. Watch this video to get the hang of things.  [see enlightening video in 2020 MS thread]

Thanks, Oren!   From this video, the root cause seems like it might be that there's a general clockwise circulation as seen looking down from the North Pole (Coriolis effect?) and the CAA is kind of a "collector" for this circulation, possibly because it extends almost as far N. as Greenland, but is in the 'lee' (as it were) of Greenland itself.  The video suggests the physics is more like that of a viscous liquid than a solid. 

Apropos of that, tonight we made chocolate gelato and watched a viscous liquid slowly morph into a (almost) solid.  Now it's really hardening in the freezer :-).

"When the melt ponds drain apparent compaction goes up because the satellite sees ice, not water in ponds." - FOoW

binntho

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3352 on: June 26, 2020, 08:04:01 AM »
I clearly confused "Stupid" questions with dumb answers.
8) good one!
because a thing is eloquently expressed it should not be taken to be as necessarily true
St. Augustine, Confessions V, 6

nanning

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3353 on: June 26, 2020, 03:45:18 PM »
binntho, I owe you an apology for my misunderstanding.

It would've been clearer to me if you had written "Nuclear winter is only possible by detonation of nuclear warheads.".
« Last Edit: June 26, 2020, 05:16:16 PM by oren »
"It is preoccupation with possessions, more than anything else, that prevents us from living freely and nobly" - Bertrand Russell
"It is preoccupation with what other people from your groups think of you, that prevents you from living freely and nobly" - Nanning
Why do you keep accumulating stuff?

Tom_Mazanec

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3354 on: June 26, 2020, 03:55:56 PM »
Not only that, or Tsar Bomba would have affected the weather. The explosions have to be such as to generate giant firestorms. Even conflagrations aren’t enough...it has to be a mountainous tornado of fire as opposed to a sea of fire.

binntho

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3355 on: June 27, 2020, 05:58:20 AM »
binntho, I owe you an apology for my misunderstanding.

It would've been clearer to me if you had written "Nuclear winter is only possible by detonation of nuclear warheads.".
Apology accepted, and extra clarity promised in the future! And as Sebastian points out, just because the questions are "stupid" doesn't mean that the answers have to be dumb - I guess we all fall into that trap every now and then.
because a thing is eloquently expressed it should not be taken to be as necessarily true
St. Augustine, Confessions V, 6

KenB

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3356 on: June 30, 2020, 03:25:57 PM »
Is there an inventory of Arctic stations and their sensors?  I tried googling and didn't find much. 
As an example, I recently found out what a pyrheliometer is and I now know there's one in Alert (thanks to GAWLab).  Found myself wondering where there were others, and then from there where there were other sensors.

"When the melt ponds drain apparent compaction goes up because the satellite sees ice, not water in ponds." - FOoW

oren

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3357 on: June 30, 2020, 05:26:29 PM »
Most Arctic stations (except some Alaska stations for some reason) provide SYNOP reports and are available via various websites. Some use METAR instead or in addition. Warning: I have no clue what or why this is, I am just a practical user.
I personally use ogimet (a Spanish website) for individual stations. It has a map showing all stations in an area which is quite useful (and works most of the time). However, I am not aware of a list of the special instruments in  various stations.
Link to ogimet map (requires panning, zooming out and selecting desired variable such as max temp, not very friendly):
https://www.ogimet.com/cgi-bin/ogimet_nav?lang=en&lat=75N&lon=-075

Link to the reports by a specific station (Eureka):
https://www.ogimet.com/cgi-bin/gsynres?lang=en&ind=71917&ndays=30&ano=2020&mes=6&day=30&hora=15&min=13

nanning

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3358 on: July 01, 2020, 04:50:51 AM »
oren, I got this from my Firefox browser when I clicked on the ogimet.com links:
Quote
Firefox detected an issue and did not continue to www.ogimet.com. The website is either misconfigured or your computer clock is set to the wrong time.

It’s likely the website’s certificate is expired, which prevents Firefox from connecting securely. If you visit this site, attackers could try to steal information like your passwords, emails, or credit card details.
(my computer time matches the forum time)

This doesn't say whether the site itself is bad. I won't visit that page because I'm careful.
"It is preoccupation with possessions, more than anything else, that prevents us from living freely and nobly" - Bertrand Russell
"It is preoccupation with what other people from your groups think of you, that prevents you from living freely and nobly" - Nanning
Why do you keep accumulating stuff?

blumenkraft

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3359 on: July 01, 2020, 07:56:06 AM »
It's a privacy issue, not a security issue. It's HTTP instead of HTTPS (due to the expired certificate).

So if you don't have a problem with everyone knowing you are visiting this site, it's fine to go there.

oren

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3360 on: July 01, 2020, 08:26:05 AM »
The site is legit. This issue with https started yesterday, hopefully it will be resolved soon. But I am sure other sites can be used as well for the same purpose.

sidd

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3361 on: July 01, 2020, 08:39:31 PM »
Re: everyone knowing you are visiting this site

Using https will not disguise the fact that you are visiting this site, it only conceals the material on the site that you are looking at, not the fact that you visited this site.

If you want to conceal the sites that you are visiting, use Tor  or such.

sidd
« Last Edit: July 01, 2020, 08:45:51 PM by sidd »

blumenkraft

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3362 on: July 01, 2020, 08:58:17 PM »
Absolutely right, Sidd! Thanks for the correction.

sidd

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3363 on: July 02, 2020, 07:47:07 AM »
[Probably better in another thread, but relevant ]

Re: more https

https security depends on the security of the CA (the guy, call him Joe, that issues the certificate to the site you are visiting)

If you are sufficiently paranoid (as i am on occasion) you will question if Joe is himself secure. Especially since every government in the world as well as many, many other non state entities realize that breaking the small number of Joes of this world and getting the keys to every site that Joe issued a cert for is much easier than breaking the vast number of each site individually ...

sidd


Freegrass

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3364 on: July 04, 2020, 01:53:03 AM »
If the entire ice pack starts rotating, will that cause Ekman pumping and thus more bottom melting?
90% of the world is religious, but somehow "love thy neighbour" became "fuck thy neighbours", if they don't agree with your point of view.

WTF happened?

oren

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3365 on: July 04, 2020, 09:08:17 AM »
Not being a hydrologist or a coriolis-ist, I think the answer is yes.
In my world, the rule of thumb is that any movement of ice increases bottom melt as it increases the rate of transfer of energy and salinity between the ice and the water column. Or in layman words, stirring a glass containing water and ice hastens the melt-out.

https://en.wikipedia.org/wiki/Ekman_transport
Quote
Ekman transport is part of Ekman motion theory, first investigated in 1902 by Vagn Walfrid Ekman. Winds are the main source of energy for ocean circulation, and Ekman Transport is a component of wind-driven ocean current. Ekman transport occurs when ocean surface waters are influenced by the friction force acting on them via the wind. As the wind blows it casts a friction force on the ocean surface that drags the upper 10-100m of the water column with it. However, due to the influence of the Coriolis effect, the ocean water moves at a 90° angle from the direction of the surface wind. The direction of transport is dependent on the hemisphere: in the northern hemisphere, transport occurs at 90° clockwise from wind direction, while in the southern hemisphere it occurs at a 90° counterclockwise. This phenomenon was first noted by Fridtjof Nansen, who recorded that ice transport appeared to occur at an angle to the wind direction during his Arctic expedition during the 1890s. Ekman transport has significant impacts on the biogeochemical properties of the world's oceans. This is because they lead to upwelling (Ekman suction) and downwelling (Ekman pumping) in order to obey mass conservation laws. Mass conservation, in reference to Ekman transfer, requires that any water displaced within an area must be replenished. This can be done by either Ekman suction or Ekman pumping depending on wind patterns.

ajouis

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3366 on: July 05, 2020, 07:29:50 AM »
I have seen some people here say there is no real academic evidence for an amoc slowdown, while I have seen studies backing it up, am I missing something?
After a thousand steps on the ice, it cracked.
The Man looked down at the infinite blue of the sea.
On the horizon, standing still, the polar bear had just scented his next meal.

 Less than 3000 cubic kilometers this Piomas minimum.

Tom_Mazanec

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3367 on: July 05, 2020, 09:59:02 AM »
Here is a question:
We are now a fraction of a degree hotter than the Holocene Maximum. How do we compare with the Eemian?

kassy

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3368 on: July 05, 2020, 06:00:31 PM »
Well that is the territory we are heading for but it lasted 15k years or so and of course we don´t have exact temps just measures of peak warmth and other proxies. The north sea was 2 degrees celsius hotter then now so that will take a while.
Þetta minnismerki er til vitnis um að við vitum hvað er að gerast og hvað þarf að gera. Aðeins þú veist hvort við gerðum eitthvað.

mw

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3369 on: July 06, 2020, 06:13:14 PM »
Hi!

Is this a "surge" on Komsomolets Island (see the link below) similar to what happend on October Revolution Island with Vavilov?

https://worldview.earthdata.nasa.gov/?v=645479.0871456721,807844.0165125381,699239.0871456721,837348.0165125381&p=arctic

Thanks for the forum!


Best regards!


oren

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3370 on: July 07, 2020, 03:31:45 AM »
Welcome mw!
My tired eyes can't see what you are referring to, but maybe someone else can, or you can direct us to the specific part of the image you are referring to and what other date to compare it to.

mw

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3371 on: July 07, 2020, 09:54:41 AM »
Thanks for the warm welcome, Oren.

See the first two images for the location in question. It looks similar to the nearby Vavilov surge for me which can be seen on the last image.


blumenkraft

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3372 on: July 07, 2020, 10:27:10 AM »
Hi!

Hey there, welcome to the forum! :)

Quote
Is this a "surge" on Komsomolets Island (see the link below) similar to what happend on October Revolution Island with Vavilov?

(If you are talking about the polynya:)

For how i see it, it works like that: The snow on the rocks melts, flows onto the ice, stays there for a while until it drains through the ice. The draining makes holes into the ice that are getting bigger during the melting season.

But yes, it seems likely to me that you would have an upwelling in this area. This is also a factor to consider.

Jim Hunt

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3373 on: July 07, 2020, 11:47:49 AM »
Quote
Is this a "surge" on Komsomolets Island (see the link below) similar to what happend on October Revolution Island with Vavilov?

(If you are talking about the polynya:)

I'm pretty sure MW is referring to the recent "surge" of the Vavilov Ice Cap into the ocean:

https://go.nasa.gov/2D90Fwf

Zooming out a bit at their link makes the proposed new "surge" more obvious?
"The most revolutionary thing one can do always is to proclaim loudly what is happening" - Rosa Luxemburg

blumenkraft

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3374 on: July 07, 2020, 11:54:10 AM »
Oh, OK. I totally misunderstood then. Sorry.

This ice cap is doing that for some while now, right! Now i remember.

https://earthobservatory.nasa.gov/images/144790/a-surprising-surge-at-vavilov-ice-cap

Jim Hunt

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"The most revolutionary thing one can do always is to proclaim loudly what is happening" - Rosa Luxemburg

blumenkraft

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3376 on: July 07, 2020, 12:53:06 PM »
And here as GIFs. First one January to July this year, the second one over the years.
« Last Edit: July 07, 2020, 01:41:54 PM by blumenkraft »

oren

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3377 on: July 07, 2020, 01:25:04 PM »
I have belatedly approved a follow-on post by mw above. Sorry for the delay.

Now I see what was meant. Nice find.

oren

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3378 on: July 07, 2020, 03:33:56 PM »
Please, not here Tom. These questions are ice related.

Phoenix

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3379 on: July 07, 2020, 10:19:34 PM »
Is there a source for NSIDC regional area values for 30 years ago?

According to Nico Sun's AWP model, the Beaufort Sea is experiencing conditions similar to what might have been normal ~ 1990.

I'm wondering how much ice used to exist at the minimum back then.

oren

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3380 on: July 07, 2020, 11:20:47 PM »
Regional data (extent and area) for each sea is available in one spreadsheet file from the NSIDC website, covering all years since 1978 with a few missing chunks of data here and there.

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oren

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3382 on: July 08, 2020, 02:11:38 AM »

Tom_Mazanec

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3383 on: July 08, 2020, 07:15:56 PM »
What was special about 2012?
Why did arctic ice go so far down below the trendline that, even after eight years of rapidly worsening AGW, we are probably not going to approach, much less break, the record.
Was there a freak heat wave? A very big storm? What?

The Walrus

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3384 on: July 08, 2020, 07:20:38 PM »
What was special about 2012?
Why did arctic ice go so far down below the trendline that, even after eight years of rapidly worsening AGW, we are probably not going to approach, much less break, the record.
Was there a freak heat wave? A very big storm? What?

There was a very big storm.  You can read about it at these links:

http://nsidc.org/arcticseaicenews/2012/08/a-summer-storm-in-the-arctic/#:~:text=On%20three%20consecutive%20days%20(August,wave%20action%20during%20the%20storm.

https://www.climatecentral.org/news/storm-accelerated-arctic-sea-ice-loss-in-2012-study-finds-15542

igs

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3385 on: July 08, 2020, 07:24:17 PM »
What was special about 2012?
Why did arctic ice go so far down below the trendline that, even after eight years of rapidly worsening AGW, we are probably not going to approach, much less break, the record.
Was there a freak heat wave? A very big storm? What?

It was some preconditioning plus a huge long lasting cyclone in August that not only was strong and persistent but also blew exactly the right way.

BTW this is basic knowledge I'm surprised but since we're in this thread I hope that I was able to give the right answer. Someone certainly will add more details, so I keep it short.

Tom_Mazanec

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3386 on: July 08, 2020, 07:26:36 PM »
The two references seem to waffle on the importance of the storm, though:
Quote
The “Great Arctic Cyclone of 2012,” which struck the Arctic at the height of the sea ice melt season in early August, was not responsible for causing sea ice extent to plunge to a record low just a few weeks later. That is one of the conclusions of a new study published in the journal Geophysical Research Letters.
Quote
Arctic sea ice extent during the first two weeks of August continued to track below 2007 record low daily ice extents. As of August 13, ice extent was already among the four lowest summer minimum extents in the satellite record, with about five weeks still remaining in the melt season. Sea ice extent dropped rapidly between August 4 and August 8. While this drop coincided with an intense storm over the central Arctic Ocean, it is unclear if the storm prompted the rapid ice loss.
Is it in retrospect that the storm seems so important?

igs

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3387 on: July 08, 2020, 10:16:23 PM »
The two references seem to waffle on the importance of the storm, though:
Quote
The “Great Arctic Cyclone of 2012,” which struck the Arctic at the height of the sea ice melt season in early August, was not responsible for causing sea ice extent to plunge to a record low just a few weeks later. That is one of the conclusions of a new study published in the journal Geophysical Research Letters.
Quote
Arctic sea ice extent during the first two weeks of August continued to track below 2007 record low daily ice extents. As of August 13, ice extent was already among the four lowest summer minimum extents in the satellite record, with about five weeks still remaining in the melt season. Sea ice extent dropped rapidly between August 4 and August 8. While this drop coincided with an intense storm over the central Arctic Ocean, it is unclear if the storm prompted the rapid ice loss.
Is it in retrospect that the storm seems so important?

Now we come into Phoenician territory.

It is well established knowledge, as close to a fact as it can get and then we all can find an opposing opinion to absolutely EVERYTHING. Even that the world is round is still challenged.

I'm out of this, already regret to have taken this on. The question was strange and so was the reply. One cannot really expect to get into a serious dispute about the impact of the August GAC in 2012, sorry.

Phoenix

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3388 on: July 08, 2020, 11:28:11 PM »
What was special about 2012?
Why did arctic ice go so far down below the trendline that, even after eight years of rapidly worsening AGW, we are probably not going to approach, much less break, the record.
Was there a freak heat wave? A very big storm? What?

1. 2012 started out low. The 2011 minimum was a record.

2. The 2011-12 freezing season was not a good one. <2012 Had higher volume and very high extent/area at end of winter. O>

3. The 2012 melting season was prolonged as evidenced by the DMI 80N. It hit the 0C threshold early and lingered late.

4. The Mackenzie delta discharge was delayed. 300k+ km3 of shallow water remained at lower latitude and heated up to an average temp of ~ 10C because the fast ice allowing it to enter the CAB was slow to break up. Fresh warm water is the least dense so it remained at the surface when it entered the Beaufort and did a number on the ice.

5. GAC

6. Unusual compaction which resulted in the 2D extent # being inordinately low.
« Last Edit: July 09, 2020, 05:09:50 AM by oren »

oren

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3389 on: July 09, 2020, 05:21:01 AM »
Off the top of my head, 2012 mostly had early preconditioning in May with snow melt and melt ponds. Then June had high insolation which decimated the preconditioned ice. The August GAC was the icing on the cake, it finished off thin ice and brought more energy from below thanks to Ekman transport.

Tom, the best way to educate yourself is to read the posts made by Neven on Arctic Sea Ice Blog at the time.

https://neven1.typepad.com/blog/asi-update-2012/

The order is reversed. Best start from update 1 and read on to update 11. Take your time, it is highly educational.
Note to self: Find the time to do the same.

You can also read the NSIDC analysis posted at the time. Click the link and then click "Next" at the top to cycle through the updates.
http://nsidc.org/arcticseaicenews/2012/06/arctic-sea-ice-variable-ends-may-below-average/
« Last Edit: July 09, 2020, 05:31:16 AM by oren »

Tom_Mazanec

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3390 on: July 09, 2020, 01:35:16 PM »
Well, whatever the answer, sooner or later it or something like it will happen again, only with the "baseline" even lower as "normal" sea ice shrinks.
Then we will really see something.

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3391 on: July 09, 2020, 04:25:50 PM »
What was special about 2012?
Why did arctic ice go so far down below the trendline that, even after eight years of rapidly worsening AGW, we are probably not going to approach, much less break, the record.
Was there a freak heat wave? A very big storm? What?

1. 2012 started out low. The 2011 minimum was a record.

2. The 2011-12 freezing season was not a good one. <2012 Had higher volume and very high extent/area at end of winter. O>

3. The 2012 melting season was prolonged as evidenced by the DMI 80N. It hit the 0C threshold early and lingered late.

4. The Mackenzie delta discharge was delayed. 300k+ km3 of shallow water remained at lower latitude and heated up to an average temp of ~ 10C because the fast ice allowing it to enter the CAB was slow to break up. Fresh warm water is the least dense so it remained at the surface when it entered the Beaufort and did a number on the ice.

5. GAC

6. Unusual compaction which resulted in the 2D extent # being inordinately low.

According to NSIDC data, 2011 was second lowest Arctic sea ice extent.  2007 was the record lowest at the time.  2012 started the melt season quite high - it.  It is the second highest maximum (barely edged out by 2008) since 2003.  The ice remained [relatively] high until June, when it took its first dive, falling to a close second (to 2010) by July.  July melt was about average, and by month's end was slightly ahead of 2007 for lowest extent.  The ice started melting rapidly the second week of August, which intensified during the cyclone.  The extensive melt during the second half of August distinguishes 2012 from all the other years. 

The low was reached on Sept. 17, which is about average.  The record low was followed by a near record sea ice growth, exceeded only by 2008 with followed the previous record low in 2007.  The 2020 maximum (second highest since the 2012 record low) was less than a century mark below the 2013 maximum. 

Will it happen again?  Not sure.  It has happened only once during the satellite era, and the baseline is not any lower than before. 
« Last Edit: July 10, 2020, 07:11:59 PM by The Walrus »

Phoenix

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3392 on: July 09, 2020, 08:16:07 PM »
What do we expect to happen when surface temperatures in some areas (Pacific side) go below zero during the coming days?

Do we expect some melt ponds to refreeze?

Note: Temps are not expected to go below -1.8C afaik, so typical seawater should not be expected to freeze, but I think melt ponds should be lower salinity.


igs

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3393 on: July 10, 2020, 04:17:17 AM »
What do we expect to happen when surface temperatures in some areas (Pacific side) go below zero during the coming days?

Do we expect some melt ponds to refreeze?

Note: Temps are not expected to go below -1.8C afaik, so typical seawater should not be expected to freeze, but I think melt ponds should be lower salinity.


Depends on insoltation. As long as the sun is shining, snow and ice melt even well below zero. I assume that once there are clouds or fog at this time of the year, temps won't drop significantly below zero because clouds keep the heat quite well underneath.

oren

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3394 on: July 10, 2020, 04:47:23 AM »
It is quite typical that melt pond surfaces freeze over when the sky becomes cloudy and temps go colder. Often it's just a thin layer of floating ice. However, the location of the melt pond remains the most vulnerable and as soon as conditions turn around the pond normally returns right where it was.
To understand what really happens in situ, I strongly recommend watching all the movies archived as part of the O-Buoy project that ran a few years back. Must-see for any sea ice enthusiast.

Try this one first.
http://obuoy.datatransport.org/monitor#buoy14/movie
Best to watch the whole 25 minutes, but if you're in a hurry just watch the 2016 season unfolding in the Beaufort/CAB, with melt ponds appearing in late June and the floe breaking up in August. Lots of occasions where the melt ponds are widening and then refreezing. (05:00 to 08:00). Amazingly the buoy survives until next season in the CAA, with ponds again appearing in late June. (16:00 to 22:00).
Conditions appear to have been mostly cloudy both seasons, but one can discern the quick result of the sun making an appearance. While watching, try to imagine the effects of weather that leads to melt pond formation a month earlier, and mostly sunny skies.

As proof of watching - when do the bear tracks appear?

Other movies:
http://obuoy.datatransport.org/monitor#buoy2/movie
Short, 2011

http://obuoy.datatransport.org/monitor#buoy4/movie
2012, deep CAB and Fram

http://obuoy.datatransport.org/monitor#buoy5/movie
2011, Beaufort/CAB

http://obuoy.datatransport.org/monitor#buoy6/movie
2012, deep CAB and Fram

http://obuoy.datatransport.org/monitor#buoy7/movie
2013, Beaufort, with open ocean and new ice refreeze at the end

http://obuoy.datatransport.org/monitor#buoy9/movie
2014+2015, CAB and Fram

http://obuoy.datatransport.org/monitor#buoy10/movie
2014+2015, Beaufort

http://obuoy.datatransport.org/monitor#buoy11/movie
2015, Beaufort

http://obuoy.datatransport.org/monitor#buoy12/movie
2015, Chukchi/CAB

Tom_Mazanec

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3395 on: July 10, 2020, 02:00:33 PM »
Anyone know where I can get a list of king tide dates for this decade?

kassy

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3396 on: July 10, 2020, 02:41:42 PM »
They are provided on a yearly bases per location so just keep collecting them.

Also try to keep the context in mind because you are probably not looking for Arctic king tides...
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Tom_Mazanec

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3397 on: July 10, 2020, 03:28:18 PM »
Yeah, Atlantic and Gulf would be more pertinent than Arctic.

gerontocrat

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3398 on: July 10, 2020, 06:14:50 PM »
Yeah, Atlantic and Gulf would be more pertinent than Arctic.
You are unlikely to find anything beyond one year. King tides, often known elsewhere as Spring Tides, tend to occur close to the Spring and Autumn equinoxes, when the earth's rotation is in close alignment with the sun and the moon. During the moon's 29 day cycle the highest tides are at new and full moon. You can get New Moon and Full Moon dates for anywhere from this site..

https://www.timeanddate.com/moon/phases/usa/fort-lauderdale

The highest tides in the Gulf occur in Autumn when sea temperatures are at maximum,which increases the general sea level. Hence the table below.

King Tides and High Tides | City of Fort Lauderdale
Anticipated King Tides in 2020


September 16 - 22.
October 14 - 21.
November 13 - 18.
December 13 - 15.

Of course September & October are also high risk months for Hurricanes. One day a hurricane will make landfall with a nasty storm surge on top of a King Tide.

Note that this year the New Moon on October 16 is a Super Moon - i.e. the moon closer than usual to the earth. The King tide could be bigly on that date.
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Frosty

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Re: "Smart" and "Stupid" Questions - Feel Free To Ask
« Reply #3399 on: July 15, 2020, 03:50:30 PM »
Apologies if this has been asked already and I have missed it.

What accounts for the difference in extent between NSIDC and ADS/JAXA? For example on July 12 (Before a few days of suspicious NSIDC numbers), ice extent was 7.747 million KM2, while ADS reported 7.45 million KM2, which is 300,000km2 lower, or nearly 4%?

Given this difference between the datasets is consistent, and they both use a 15% threshold for extent, can this be fully explained by using a different grid?