Support the Arctic Sea Ice Forum and Blog

Author Topic: The 2015 melting season  (Read 2323731 times)

Vergent

  • Grease ice
  • Posts: 574
    • View Profile
  • Liked: 2
  • Likes Given: 2
Re: The 2015 melting season
« Reply #1400 on: June 19, 2015, 03:25:54 AM »
I will try my first gif


Not well tuned  :(
Its 40 days or so of Beaufort front evolution form MODIS

I see a few interesting things but its so late, took so long, tomorrow.
Quote
Your client does not have permission to get URL /gRps85BKsmrJZ57_G5JZb7XF9LLTro4ej2FsXLlfvNqHzacrNOkY3onF7HRc-ResEAJv4rXSVK8jN-4=w1272-h1544 from this server.

It looks like the linked site requires a sign in. You may have to designate the image as public, or use another site like Imgur.com.

Verg
« Last Edit: June 19, 2015, 03:32:57 AM by Vergent »

seaicesailor

  • Guest
Re: The 2015 melting season
« Reply #1401 on: June 19, 2015, 03:48:27 AM »
I will try my first gif
Not well tuned  :(

Its 40 days or so of Beaufort front evolution form MODIS
I see a few interesting things but its so late, took so long, tomorrow.

What the heck l, I cant sleep today (not because of the Arctic though)

- The MYI is broken up in huge floes.

- These are North of CAA on early May, but drift toward Beaufort, especially a couple of huge floes. The open water in Beaufort widens due to southern winds too.

- Meanwhile Alaska loses almost all snow cover, clean skies are observed for quite a few days, ice turnes blueish. McKenzie river discharge starts.  Open water must be warming up. Albedo (land and ocean) goes down very quickly.

- Then for 20 days or so the ice edge does not advance much, but MYI keeps turning, and  getting well into Beaufort Sea. Also diverging drift of the floes is apparent, and maybe some of the smallest floes disappearing from the picture (speculation).

- HYCOM predicts that drift will push MYI further toward coast and McKenzie river region for the next few days.

- My speculation is that great part of  MYI that approaches the coast is going to melt out completely even when the ice edge seems not to advance. Maybe ironically some North component of winds ends up being fatal for these enormous thick blocks.
- There is also a more homogeneous (thinner?) ice close to coast that is melting faster and drifting toward Barrow. Very blue ice. That should melt out sooner.

Vergent

  • Grease ice
  • Posts: 574
    • View Profile
  • Liked: 2
  • Likes Given: 2
Re: The 2015 melting season
« Reply #1402 on: June 19, 2015, 04:33:24 AM »
seaicesailor,



A lot of that thick ice in and near the Beaufort isn't all that thick. This is thickness actually measured by CRYOSAT2. The truly thick stuff is more centrally located.

Verg

seaicesailor

  • Guest
Re: The 2015 melting season
« Reply #1403 on: June 19, 2015, 08:17:27 AM »
It may not be as thick, but isnt MYI much tougher to melt than FYI with same thickness?

helorime

  • Frazil ice
  • Posts: 129
    • View Profile
  • Liked: 3
  • Likes Given: 18
Re: The 2015 melting season
« Reply #1404 on: June 19, 2015, 01:05:25 PM »
Yes.  FYI has more salt and a lower melting temp as a result.  The salt slowly gets purged from the ice over time.  The salt forms brine pockets as the ocean water freezes, compression over time tends to break those pockets and squeeze out the salt.  In summer melt water can wash through remaining channels and if the ice survives the summer it then refreezes more solidly with less salt.

Note: Edited to correct my reversed first sentence.  Yikes! Said higher when I meant lower.
« Last Edit: June 19, 2015, 05:13:34 PM by helorime »
Any sufficiently advanced technology is indistinguishable from magic.

LRC1962

  • Frazil ice
  • Posts: 446
    • View Profile
  • Liked: 11
  • Likes Given: 3
Re: The 2015 melting season
« Reply #1405 on: June 19, 2015, 01:25:02 PM »
It may not be as thick, but isnt MYI much tougher to melt than FYI with same thickness?
There is a 'but' that I see "What is MYI?", in today's ASI? With ASI at such so low levels and thicknesses at also all time lows, MYI can be broken apart and pushed together much more frequently then in the past. Each time that happens more salt gets mixed into the ice. along with that is more and more algae which also is at all time growth rates. Put that all together, how much pure MYI truly is left in the Arctic?
"All truth passes through three stages: First, it is ridiculed; Second,  it is violently opposed; and Third, it is accepted as self-evident."
       - Arthur Schopenhauer

F.Tnioli

  • Grease ice
  • Posts: 772
    • View Profile
  • Liked: 147
  • Likes Given: 38
Re: The 2015 melting season
« Reply #1406 on: June 19, 2015, 01:38:54 PM »


The last data import was Monday, so this may not reflect the snow/rain if it was not forecast. Will post  next Monday when it will be primarily observation based.

Verg
That big purple thingie next to North pole, surrounded mostly by green and red... That's thousands and thousands square miles of ~0.5 albedo right next to the pole, yes? Sigh. If that gets fried by the sun, i say the pole could end up quite a warm sea by the end of August - and open water way before it. Would surely be a newsliner if it'd happen, eh.
To everyone: before posting in a melting season topic, please be sure to know contents of this moderator's post: https://forum.arctic-sea-ice.net/index.php/topic,3017.msg261893.html#msg261893 . Thanks!

F.Tnioli

  • Grease ice
  • Posts: 772
    • View Profile
  • Liked: 147
  • Likes Given: 38
Re: The 2015 melting season
« Reply #1407 on: June 19, 2015, 01:48:57 PM »
... Put that all together, how much pure MYI truly is left in the Arctic?
I don't remember exact numbers, but there were papers on this. Few percent is what's truly left. Something about 4% IIRC. Don't quote me on this though, please. Sadly, i can't find either of those right now; what little i remember is that those were published few years ago, and the research was about "old" MYI - ice which was around (most of its thickness anyway) not for a few years (2...5), but for dozens/hundreds years, and that sort of MYI was found to be much more resilient than "fresh" MYI. And thicker, too. Very little of that ice remains today.
« Last Edit: June 19, 2015, 02:10:15 PM by F.Tnioli »
To everyone: before posting in a melting season topic, please be sure to know contents of this moderator's post: https://forum.arctic-sea-ice.net/index.php/topic,3017.msg261893.html#msg261893 . Thanks!

Nightvid Cole

  • Frazil ice
  • Posts: 438
    • View Profile
  • Liked: 5
  • Likes Given: 0
Re: The 2015 melting season
« Reply #1408 on: June 19, 2015, 01:53:12 PM »


The last data import was Monday, so this may not reflect the snow/rain if it was not forecast. Will post  next Monday when it will be primarily observation based.

Verg
That big purple thingie next to North pole, surrounded mostly by green and red... That's thousands and thousands square miles of ~0.5 albedo right next to the pole, yes? Sigh. If that gets fried by the sun, i say the pole could end up quite a warm sea by the end of August - and open water way before it. Would surely be a newsliner if it'd happen, eh.

I wouldn't be so fast to leap to that conclusion. We saw a much bigger area with similarly dispersed ice near the Pole in 2013. While it did turn to "slush" with only about 40% concentration over a large area by August 27/28 IIRC, it didn't completely melt.

Even if it does melt this year due to surface melt being more advanced than this time in 2013, by the time the slush floes are gone it will be after August 15, and there will only be a week or so left before the sun is simply too weak to warm the water. So the water temperature cannot get very far above freezing. I'd expect a maximum SST of around 1 degree C, and I would be absolutely shocked to see the SST reach 3 degrees C (and I'd assume the model was wrong unless corroborated).

« Last Edit: June 19, 2015, 02:00:07 PM by Nightvid Cole »

seaicesailor

  • Guest
Re: The 2015 melting season
« Reply #1409 on: June 19, 2015, 02:11:27 PM »
... Put that all together, how much pure MYI truly is left in the Arctic?
I don't remember exact numbers, but there were papers on this. Few percent is what's truly left. Something about 4% IIRC. Don't quote me on this though, please.

But don't you think it is not how much it is but where it is? A big portion of MYI is in Beaufort-Chukchi; what happens with that is a big "?" as many people say. My point is that the Beaufort part is in the right place to be melted if conditions allow (like drifting closer to the coast where warm water and land affect ice very much), and Chukchi is already a mess. If that doesn't play out, much of it may survive, then albedo does not drop as much, and ice cap is further protected.

See map of ice age (red is +5 year old age)

ccar.colorado.edu/pub/tschudi/iceage/gifs/age2015_20.gif

@ Helorime: just a sign correction, surely you meant FYI has a lower melting point.

Edit: a fraction of thr MYI is not in the Chukchi but in the CAB close to Chukchi sea. Still in place.
« Last Edit: June 19, 2015, 02:24:03 PM by seaicesailor »

F.Tnioli

  • Grease ice
  • Posts: 772
    • View Profile
  • Liked: 147
  • Likes Given: 38
Re: The 2015 melting season
« Reply #1410 on: June 19, 2015, 02:12:54 PM »
But it wasn't a conclusion: i said, "If that gets fried by the sun". Please do note the "if" and "fried" words. Not stating pole will go all blue; stating there is now one of several required pieces clicked nearly into place (low albedo in the region). Sir.
To everyone: before posting in a melting season topic, please be sure to know contents of this moderator's post: https://forum.arctic-sea-ice.net/index.php/topic,3017.msg261893.html#msg261893 . Thanks!

seaicesailor

  • Guest
Re: The 2015 melting season
« Reply #1411 on: June 19, 2015, 02:21:22 PM »
But it wasn't a conclusion: i said, "If that gets fried by the sun". Please do note the "if" and "fried" words. Not stating pole will go all blue; stating there is now one of several required pieces clicked nearly into place (low albedo in the region). Sir.

Ok, I get it.
What s with the "Sir" thing? Did I bother you? I am not so old  8) nor named Sir by the Queen, not even British.

F.Tnioli

  • Grease ice
  • Posts: 772
    • View Profile
  • Liked: 147
  • Likes Given: 38
Re: The 2015 melting season
« Reply #1412 on: June 19, 2015, 02:22:53 PM »
... Put that all together, how much pure MYI truly is left in the Arctic?
I don't remember exact numbers, but there were papers on this. Few percent is what's truly left. Something about 4% IIRC. Don't quote me on this though, please.

But don't you think it is not how much it is but where it is? A big portion of MYI is in Beaufort-Chukchi; what happens with that is a big "?" as many people say. My point is that the Beaufort part is in the right place to be melted if conditions allow (like drifting closer to the coast where warm water and land affect ice very much), and Chukchi is already a mess. If that doesn't play out, much of it may survive, then albedo does not drop as much, and ice cap is further protected.

See map of ice age (red is +5 year old age)

ccar.colorado.edu/pub/tschudi/iceage/gifs/age2015_20.gif

@ Helorime: just a sign correction, surely you meant FYI has a lower melting point.
Yep, good map. Note how there are wide continuous fields of 2-year, 3-year and 4-year ice - those are big fields which didn't melt "since" they formed (not any much, at least). But red color is all dotted by other colors - nearly all that older ice (5+ years) is damaged goods. I remember seeing similar map few years ago which was made for 1980, - in here colors, it would be huge blocks of continuous red, without various-colors dots embedded into 'em.

...
What s with the "Sir" thing? Did I bother you? I am not so old  8) nor named Sir by the Queen, not even British.
A clumsy attempt (i am the one who's clumsy) to show respect to you, nothing more. English is not my native language. I am still sure that "sir" sounds better than "pal", though.  8)
« Last Edit: June 19, 2015, 02:31:03 PM by F.Tnioli »
To everyone: before posting in a melting season topic, please be sure to know contents of this moderator's post: https://forum.arctic-sea-ice.net/index.php/topic,3017.msg261893.html#msg261893 . Thanks!

seaicesailor

  • Guest
Re: The 2015 melting season
« Reply #1413 on: June 19, 2015, 02:42:22 PM »
2007 Week 20 was similar to current week (well, more abundant MYI, and older) then see week 40.

@Tnioli: Thank you, no problem at all, just sounded so formal ;) I am no native English speaker either




F.Tnioli

  • Grease ice
  • Posts: 772
    • View Profile
  • Liked: 147
  • Likes Given: 38
Re: The 2015 melting season
« Reply #1414 on: June 19, 2015, 03:34:47 PM »
I am assuming that blue on week #20 2007 turns into light-blue (2-years-old ice) on week #40 picture; light-blue on week 20 turns into green on week 40, and so on. Otherwise i'd have difficulties to fathom those two maps - for example, to explain how there is so much more green color on week 40 than on week 20. Blue color on week 40 would then be "new freeze season", "just formed" ice. And yes, quite similar week 20 both 2007 and 2015. Several places, very similar. But somehow i feel i can guarantee that week 40 map this year will look very, very different from week 40 2007.
« Last Edit: June 19, 2015, 03:41:37 PM by F.Tnioli »
To everyone: before posting in a melting season topic, please be sure to know contents of this moderator's post: https://forum.arctic-sea-ice.net/index.php/topic,3017.msg261893.html#msg261893 . Thanks!

seaicesailor

  • Guest
Re: The 2015 melting season
« Reply #1415 on: June 19, 2015, 03:45:58 PM »
I am assuming that blue on week #20 2007 turns into light-blue (2-years-old ice) on week #40 picture; light-blue on week 20 turns into green on week 40, and so on. Otherwise i'd have difficulties to fathom those two maps - for example, to explain how there is so much more green color on week 40 than on week 20. And yes, quite similar week 20 both 2007 and 2015. Several places, very similar. But somehow i feel i can guarantee that week 40 map this year will look very, very different from week 40 2007.

I guess because at week 40 some of the surviving ice celebrate their birthday (they were born around week 40, end of previous melting seasons), so they change color.

seaicesailor

  • Guest
Re: The 2015 melting season
« Reply #1416 on: June 19, 2015, 04:06:19 PM »
Four days of MYI divergent drift toward Beaufort coast. Meanwhile in ESS ...


Vergent

  • Grease ice
  • Posts: 574
    • View Profile
  • Liked: 2
  • Likes Given: 2
Re: The 2015 melting season
« Reply #1417 on: June 19, 2015, 04:08:02 PM »


Topaz4 keeps track of everyone's birthday ( Like that annoying aunt that always sends you a card. )

Verg

F.Tnioli

  • Grease ice
  • Posts: 772
    • View Profile
  • Liked: 147
  • Likes Given: 38
Re: The 2015 melting season
« Reply #1418 on: June 19, 2015, 04:30:13 PM »
Four days of MYI divergent drift toward Beaufort coast. Meanwhile in ESS ...
That opening in the ESS someone mentioned a bit above going to get much wider, eh? Here's a nice red near-ESS-coast cherry right for 22nd June. Picked, of course. Still, impressed. I guess the runoff will be crazy in those parts.

To everyone: before posting in a melting season topic, please be sure to know contents of this moderator's post: https://forum.arctic-sea-ice.net/index.php/topic,3017.msg261893.html#msg261893 . Thanks!

helorime

  • Frazil ice
  • Posts: 129
    • View Profile
  • Liked: 3
  • Likes Given: 18
Re: The 2015 melting season
« Reply #1419 on: June 19, 2015, 05:10:53 PM »
Yip!  Said it backwards, yes MULTIYEAR ice has a higher melting temp.  First year ice melts at a lower temp, so more quickly, due to the salt content.

Edited because I just can't seem to put the right words in the right places.  solutes in water lowers the freezing point/ melting point.
« Last Edit: June 19, 2015, 05:19:16 PM by helorime »
Any sufficiently advanced technology is indistinguishable from magic.

ChrisReynolds

  • Nilas ice
  • Posts: 1764
    • View Profile
    • Dosbat
  • Liked: 20
  • Likes Given: 9
Re: The 2015 melting season
« Reply #1420 on: June 19, 2015, 07:29:50 PM »
I am assuming that blue on week #20 2007 turns into light-blue (2-years-old ice) on week #40 picture; light-blue on week 20 turns into green on week 40, and so on. Otherwise i'd have difficulties to fathom those two maps - for example, to explain how there is so much more green color on week 40 than on week 20. And yes, quite similar week 20 both 2007 and 2015. Several places, very similar. But somehow i feel i can guarantee that week 40 map this year will look very, very different from week 40 2007.

I guess because at week 40 some of the surviving ice celebrate their birthday (they were born around week 40, end of previous melting seasons), so they change color.

Yes it is about week 40, but it varies a bt some years because they use their judgment as to when to move ages up one year.

Nightvid Cole

  • Frazil ice
  • Posts: 438
    • View Profile
  • Liked: 5
  • Likes Given: 0
Re: The 2015 melting season
« Reply #1421 on: June 19, 2015, 07:52:13 PM »
I am assuming that blue on week #20 2007 turns into light-blue (2-years-old ice) on week #40 picture; light-blue on week 20 turns into green on week 40, and so on. Otherwise i'd have difficulties to fathom those two maps - for example, to explain how there is so much more green color on week 40 than on week 20. And yes, quite similar week 20 both 2007 and 2015. Several places, very similar. But somehow i feel i can guarantee that week 40 map this year will look very, very different from week 40 2007.



I guess because at week 40 some of the surviving ice celebrate their birthday (they were born around week 40, end of previous melting seasons), so they change color.

Yes it is about week 40, but it varies a bt some years because they use their judgment as to when to move ages up one year.

The algorithm suffered a small glitch last year. Week 37 of 2014 shows a very small piece of ice in the Beaufort Sea NNE of Point Barrow which is detached from the main pack. Then in week 38, it reconnects via freshly formed ice. This freshly formed ice gets bumped up to second year ice in week 39, even though it just formed the previous week!

If it were me, I would invent a category "zeroeth year ice" for any ice that forms within the 3 weeks prior to the week that the ages are advanced. By putting in this category, this phenomenon would be avoided.

Michael Hauber

  • Nilas ice
  • Posts: 1114
    • View Profile
  • Liked: 168
  • Likes Given: 16
Re: The 2015 melting season
« Reply #1422 on: June 19, 2015, 09:57:59 PM »

That opening in the ESS someone mentioned a bit above going to get much wider, eh? Here's a nice red near-ESS-coast cherry right for 22nd June. Picked, of course. Still, impressed. I guess the runoff will be crazy in those parts.


The fast ice will break up and the broken rubble will be an expanded area of ice that the sensors will detect at near 100% concentration - whatever melt ponds do to push it down.  And once it cracks many of the melt ponds drain so the melt ponds have less impact on what the sensors detect.  So the ice state will continue to get worse, but I doubt we'll see large areas of open water or movement in the numbers being measured for either area or extent in ESS region for a couple weeks yet.
Climate change:  Prepare for the worst, hope for the best, expect the middle.

Villabolo

  • New ice
  • Posts: 72
    • View Profile
    • Global Warming Basics
  • Liked: 17
  • Likes Given: 37
Re: The 2015 melting season
« Reply #1423 on: June 20, 2015, 02:07:47 AM »
Pardon a newbie question. Will wave motion form if the ice is very broken and if so would that affect the meltdown?
« Last Edit: June 20, 2015, 02:26:55 AM by Villabolo »
In the multiversic symphony
In the place of endless possibilities
In the land of dreams we'll meet

Vergent

  • Grease ice
  • Posts: 574
    • View Profile
  • Liked: 2
  • Likes Given: 2
Re: The 2015 melting season
« Reply #1424 on: June 20, 2015, 02:55:15 AM »
Pardon a newbie question. Will wave motion form if the ice is very broken and if so would that affect the meltdown?

Welcome to ASIF

In general waves do not penetrate into the ice pack. Their effect is only on the periphery.

Verg :)

LRC1962

  • Frazil ice
  • Posts: 446
    • View Profile
  • Liked: 11
  • Likes Given: 3
Re: The 2015 melting season
« Reply #1425 on: June 20, 2015, 03:44:21 AM »
Pardon a newbie question. Will wave motion form if the ice is very broken and if so would that affect the meltdown?

Welcome to ASIF

In general waves do not penetrate into the ice pack. Their effect is only on the periphery.

Verg :)
Actually verg that is no longer the case.There are continuous reports of wave action 100's of km from the edge. That is one of the many reasons scientist working on ice is such a dangerous job now. The ice is no longer thick enough to hold the waves to the edge. That is also one of many reasons you see broken ice in the middle of the pack. http://www.scientificamerican.com/article/giant-waves-quickly-destroy-arctic-ocean-ice-and-ecosystems1/ describes one obsevered action.
"All truth passes through three stages: First, it is ridiculed; Second,  it is violently opposed; and Third, it is accepted as self-evident."
       - Arthur Schopenhauer

slow wing

  • Grease ice
  • Posts: 823
    • View Profile
  • Liked: 155
  • Likes Given: 546
Re: The 2015 melting season
« Reply #1426 on: June 20, 2015, 03:57:08 AM »
Climate Reanalyser shows lazy low pressure systems hanging over the Arctic Ocean proper for at least the next several days.
http://cci-reanalyzer.org/Forecasts/

Persumably this underlies the present pattern in the jet stream. Over what timescale might this be expected to endure?  A significant part of mid-Summer?

Vergent

  • Grease ice
  • Posts: 574
    • View Profile
  • Liked: 2
  • Likes Given: 2
Re: The 2015 melting season
« Reply #1427 on: June 20, 2015, 05:55:39 AM »
Quote
Actually verg that is no longer the case.There are continuous reports of wave action 100's of km from the edge. That is one of the many reasons scientist working on ice is such a dangerous job now. The ice is no longer thick enough to hold the waves to the edge. That is also one of many reasons you see broken ice in the middle of the pack. http://www.scientificamerican.com/article/giant-waves-quickly-destroy-arctic-ocean-ice-and-ecosystems1/ describes one obsevered action.

Here is where that event occurred:

https://www.google.com/maps/place/Hopen,+Svalbard+and+Jan+Mayen/@74.3636453,27.4259949,4z/data=!4m2!3m1!1s0x45a3d1592a2ac86f:0x5dabaeab5b79cf8a?hl=en

edit: Actually 80 miles south.



The event occurred in a tiny finger of reduced concentration ice surrounded by open water.

Quote
.There are continuous reports of wave action 100's of km from the edge.

I would be very interested if you could cite a source for this. But, I suppose it is a good introduction for  Villabolo to the forum.......Some posters just make stuff up.

Verg
« Last Edit: June 21, 2015, 04:01:38 PM by Vergent »

ChrisReynolds

  • Nilas ice
  • Posts: 1764
    • View Profile
    • Dosbat
  • Liked: 20
  • Likes Given: 9
Re: The 2015 melting season
« Reply #1428 on: June 20, 2015, 07:20:09 AM »
Vergent,

The 'hundreds' was well called. But I'll post some detail in the storms poll thread, rather than here.

EDIT - Squire says swell penetration is 'well known'.
http://forum.arctic-sea-ice.net/index.php/topic,1288.msg54483.html#msg54483
So whilst 'hundreds' may be an overstatement of the cite-able instances, there may be many more private anecdotal observations to back up the work in the scientific literature.
« Last Edit: June 20, 2015, 07:39:22 AM by ChrisReynolds »

Vergent

  • Grease ice
  • Posts: 574
    • View Profile
  • Liked: 2
  • Likes Given: 2
Re: The 2015 melting season
« Reply #1429 on: June 20, 2015, 09:11:29 AM »
Dear Chris,

I personally lived in an apartment overlooking lake Michigan in Chicago. I saw 10 foot waves impacting 50 yards of floating ice mush. By the time those waves reached the sand, they were ripples that barely sloshed back and forth. But you too can be an observer: show me a picture from AloftCon of a wave in the arctic Basin.

http://icefloe.net/Aloftcon_Photos/index.php?album=2010
http://icefloe.net/Aloftcon_Photos/index.php?album=2011
http://icefloe.net/Aloftcon_Photos/index.php?album=2012
http://icefloe.net/Aloftcon_Photos/index.php?album=2013
http://icefloe.net/Aloftcon_Photos/index.php?album=2014

Surely, if what you assert is real, there is a picture of it.

Verg

« Last Edit: June 20, 2015, 09:25:34 AM by Vergent »

seaicesailor

  • Guest
Re: The 2015 melting season
« Reply #1430 on: June 20, 2015, 10:06:33 AM »
Climate Reanalyser shows lazy low pressure systems hanging over the Arctic Ocean proper for at least the next several days.
http://cci-reanalyzer.org/Forecasts/

Persumably this underlies the present pattern in the jet stream. Over what timescale might this be expected to endure?  A significant part of mid-Summer?

Today's clouds associated to LP in MODIS, nice pic:



The fringes enjoy some sun, at least at the times images are taken. Except ESS where, well, all the warmth is entering and the ice is seoarating from fast ice.

But this picture, prolongued for a while, surely protects the Central Arctic from sun in the moment of max. insolation. So...

BTW, sorry I can't answer your question, no idea how long it will last
« Last Edit: June 20, 2015, 12:06:43 PM by seaicesailor »

Jim Hunt

  • First-year ice
  • Posts: 6268
  • Don't Vote NatC or PopCon, Save Lives!
    • View Profile
    • The Arctic sea ice Great White Con
  • Liked: 893
  • Likes Given: 87
Re: The 2015 melting season
« Reply #1431 on: June 20, 2015, 11:50:42 AM »
Verg - As a "silver" surfer with an interest in the Arctic I have investigated the literature on swells in the Arctic Basin. See for example:

http://GreatWhiteCon.info/2015/03/sea-ice-and-swells-in-the-beaufort-sea-in-the-summer-of-2014/

wherein you can see some "waves":



In answer to your specific question see also:



wherein you can see a modest "swell". I don't suppose you happen to know the period of the "10 foot waves" you observed on Lake Michigan do you?
"The most revolutionary thing one can do always is to proclaim loudly what is happening" - Rosa Luxemburg

seaicesailor

  • Guest
Re: The 2015 melting season
« Reply #1432 on: June 20, 2015, 12:14:26 PM »
They're red hot



Carex

  • New ice
  • Posts: 58
    • View Profile
  • Liked: 6
  • Likes Given: 30
Re: The 2015 melting season
« Reply #1433 on: June 20, 2015, 01:05:23 PM »
JIM H.

 "I don't suppose you happen to know the period of the "10 foot waves" you observed on Lake Michigan do you?"

I can say from experience that the wave period on The Great Lakes tends to be very short compared to ocean waters (unfortunately I don't have any suitable reference at hand).  The basins, especially near shore, are very shallow for long distances with lots of bottom drag allowing the waves to pile up.  When you look at the shallow draft of the tall ships that plied these waters you have to seriously wonder how they stayed upright.

seaicesailor

  • Guest
Re: The 2015 melting season
« Reply #1434 on: June 20, 2015, 01:21:03 PM »
Verg - As a "silver" surfer with an interest in the Arctic I have investigated the literature on swells in the Arctic Basin. See for example:

http://GreatWhiteCon.info/2015/03/sea-ice-and-swells-in-the-beaufort-sea-in-the-summer-of-2014/

wherein you can see some "waves":



In answer to your specific question see also:



wherein you can see a modest "swell". I don't suppose you happen to know the period of the "10 foot waves" you observed on Lake Michigan do you?

Wow the MYI t thatd is geared toward the coast is going to have a bumpy ride. Not only divergence, and drift toward warmer waters but also turbulent seas. Time to test many theories.

Jim Hunt

  • First-year ice
  • Posts: 6268
  • Don't Vote NatC or PopCon, Save Lives!
    • View Profile
    • The Arctic sea ice Great White Con
  • Liked: 893
  • Likes Given: 87
Re: The 2015 melting season
« Reply #1435 on: June 20, 2015, 02:11:34 PM »
Wow the MYI t thatd is geared toward the coast is going to have a bumpy ride. Not only divergence, and drift toward warmer waters but also turbulent seas. Time to test many theories.

The Arctic seas won't be turbulent for a while yet. You will note those pictures are from late August / early September last year. Generating a significant swell requires (amongst other things) many hundreds of kilometers of open water. That's much easier to come by in the Antarctic (and North Atlantic) than it is in the CAB!
"The most revolutionary thing one can do always is to proclaim loudly what is happening" - Rosa Luxemburg

seaicesailor

  • Guest
Re: The 2015 melting season
« Reply #1436 on: June 20, 2015, 02:49:02 PM »
Wow the MYI t thatd is geared toward the coast is going to have a bumpy ride. Not only divergence, and drift toward warmer waters but also turbulent seas. Time to test many theories.

The Arctic seas won't be turbulent for a while yet. You will note those pictures are from late August / early September last year. Generating a significant swell requires (amongst other things) many hundreds of kilometers of open water. That's much easier to come by in the Antarctic (and North Atlantic) than it is in the CAB!

Oops, did no realize the date of the pic. Thank you, seems obvious now to me it can't be.

seaicesailor

  • Guest
Re: The 2015 melting season
« Reply #1437 on: June 20, 2015, 03:33:54 PM »
Sorry for over-posting but I find so much interesting stuff around.

This image is from MODIS today, Bands 7-2-1 that help distinguish ice from clouds. I increased contrast on purpose. Location is North of New Siberian Islands after some beating from storm


Vergent

  • Grease ice
  • Posts: 574
    • View Profile
  • Liked: 2
  • Likes Given: 2
Re: The 2015 melting season
« Reply #1438 on: June 20, 2015, 03:58:03 PM »
Quote
Verg - As a "silver" surfer with an interest in the Arctic I have investigated the literature on swells in the Arctic Basin. See for example:

http://GreatWhiteCon.info/2015/03/sea-ice-and-swells-in-the-beaufort-sea-in-the-summer-of-2014/

wherein you can see some "waves":

The context is the outrageous claim that waves penetrate hundreds of kilometers into the ice pack. You either have waves or you have ice.... you do not get both. Again...show me a picture of a wave deep into the ice pack.

Verg

Verg

sedziobs

  • Frazil ice
  • Posts: 395
    • View Profile
  • Liked: 63
  • Likes Given: 12
Re: The 2015 melting season
« Reply #1439 on: June 20, 2015, 04:37:48 PM »
Verg, that was the original claim, since clarified by Jim and Chris to describe swells rather than waves.  So you need to add an "ice impacted by swell" to your false binary of waves or ice.  I don't have nearly enough knowledge of the issue to assess the veracity of Jim and Chris' claims, but I do not believe you are approaching this discussion in an honest manner.

Shared Humanity

  • Guest
Re: The 2015 melting season
« Reply #1440 on: June 20, 2015, 04:49:41 PM »

I personally lived in an apartment overlooking lake Michigan in Chicago. I saw 10 foot waves impacting 50 yards of floating ice mush. By the time those waves reached the sand, they were ripples that barely sloshed back and forth.

I certainly would expect that sea ice has a dampening effect on waves and their ability to penetrate  the pack. Large floes of 5 meter thick MYI, packed closely together, should dampen wave action dramatically. Widely dispersed areas of sea ice (say 60% concentration) would have a much smaller dampening effect, allowing long fetch waves to penetrate much deeper into the pack.

Having said this, your statement above completely misses how waves behave in deep ocean. Do you actually believe that the behavior of a wave at the shore of Lake Michigan has anything to do with the presence of slushy ice? I also live in Chicago, just blocks from the lake and have stood on the beach on a brutally hot and windy late fall day. I have actually seen 5 foot waves come rushing  to the beach and they miraculously turn into ripples as they spread onto the sand. If careful, I can even avoid getting my feet wet.

Do not underestimate the power of deep ocean, long fetch waves. There is simply no phenomenon on earth that can store as much mechanical energy nor pack as powerful of a punch across large surfaces of the planet.

The tsunami caused by the powerful quake in Japan broke portions of ice shelf in the Antarctic. This shelf was far thicker than 5 meters.

Tor Bejnar

  • Young ice
  • Posts: 4606
    • View Profile
  • Liked: 879
  • Likes Given: 826
Re: The 2015 melting season
« Reply #1441 on: June 20, 2015, 05:00:07 PM »
Just to remind us of the original question:
Pardon a newbie question. Will wave motion form if the ice is very broken and if so would that affect the meltdown?
Some may understand "wave motion" to include swells.  It is demonstrated that swells do penetrate and break up pack ice.  I think this is the context of the original question.  What effect do subsequent swells have on the ice?  More break up? More grinding the ice into smaller chunks, allowing for more lateral melt and decreased concentration?

If you want to be technical about "wave motion" (I'm no expect), I see two effects of waves affecting ice far from the extent edges:
  • I recall seeing pictures of melt ponds with little waves on them.  I expect these little waves, lapping on the edges of a melt pond, expand the melt pond.
  • We also have the 2012 GAC (Great Arctic Cyclone) that used wind-wiped waved to disappear a great deal of ice in the broken-up ice mass.
Arctic ice is healthy for children and other living things because "we cannot negotiate with the melting point of ice"

Jim Hunt

  • First-year ice
  • Posts: 6268
  • Don't Vote NatC or PopCon, Save Lives!
    • View Profile
    • The Arctic sea ice Great White Con
  • Liked: 893
  • Likes Given: 87
Re: The 2015 melting season
« Reply #1442 on: June 20, 2015, 05:09:56 PM »
The context is the outrageous claim that waves penetrate hundreds of kilometers into the ice pack. You either have waves or you have ice.... you do not get both. Again...show me a picture of a wave deep into the ice pack.

I can't show you a picture, but I can provide a link to such an outrageous claim in a scientific journal:

http://onlinelibrary.wiley.com/doi/10.1029/2001JC001214/pdf

Quote
Ice draft, ice velocity, ice concentration, and current profile data gathered at an array
of eight continental shelf monitoring sites east of Sakhalin Island were analyzed in
conjunction with regional meteorological data to document and explain intense wave
occurrences several hundred kilometers inside the Sea of Okhotsk ice pack.

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

Shared Humanity

  • Guest
Re: The 2015 melting season
« Reply #1443 on: June 20, 2015, 05:13:08 PM »
The context is the outrageous claim that waves penetrate hundreds of kilometers into the ice pack. You either have waves or you have ice.... you do not get both. Again...show me a picture of a wave deep into the ice pack.

I can't show you a picture, but I can provide a link to such an outrageous claim in a scientific journal:

http://onlinelibrary.wiley.com/doi/10.1029/2001JC001214/pdf

Quote
Ice draft, ice velocity, ice concentration, and current profile data gathered at an array
of eight continental shelf monitoring sites east of Sakhalin Island were analyzed in
conjunction with regional meteorological data to document and explain intense wave
occurrences several hundred kilometers inside the Sea of Okhotsk ice pack.

There you go again....getting all technical and researchy on us.    ;)

Shared Humanity

  • Guest
Re: The 2015 melting season
« Reply #1444 on: June 20, 2015, 05:31:31 PM »
I have had a very busy couple of weeks at work. I've been visiting daily and quickly scanning comments but have not commented myself. I have a had a chance to catch up this morning (much thanks to all of you) and am now increasingly alarmed by the progress of this melt season.

Vergent

  • Grease ice
  • Posts: 574
    • View Profile
  • Liked: 2
  • Likes Given: 2
Re: The 2015 melting season
« Reply #1445 on: June 20, 2015, 06:12:42 PM »
Verg, that was the original claim, since clarified by Jim and Chris to describe swells rather than waves.  So you need to add an "ice impacted by swell" to your false binary of waves or ice.  I don't have nearly enough knowledge of the issue to assess the veracity of Jim and Chris' claims, but I do not believe you are approaching this discussion in an honest manner.

Quote
There are continuous reports of wave action 100's of km from the edge.

Talk about dishonest....How do pictures of waves on an ice free Beaufort shoreline support this statement?

I specifically said the Arctic Basin. So replying with pictures from the ice free Beaufort Sea is dishonest.

https://en.wikipedia.org/wiki/Arctic_Basin

Making an accusation of dishonesty without a quote or a reference is dishonest. In the absence of a quote, it is an ad hominem attack.

I gave links to thousands of pictures of the ice cap, each has Lat/Lon and date. Find one that shows swells or waves "hundreds of kilometers from the edge", or admit that this statement was total bullshit. The only thing that happens in the basin is tides, which have a period(high to high) of about 12 hours.

Verg

Blizzard_of_Oz

  • New ice
  • Posts: 21
    • View Profile
    • 50-Day melt season forecast
  • Liked: 0
  • Likes Given: 0
Re: The 2015 melting season
« Reply #1446 on: June 20, 2015, 06:26:41 PM »
The context is the outrageous claim that waves penetrate hundreds of kilometers into the ice pack. You either have waves or you have ice.... you do not get both. Again...show me a picture of a wave deep into the ice pack.

People may have different concepts of "waves" in their minds as well as what a picture of such a thing may look like.

Kohout et al., (2014), Storm-induced sea-ice breakup and the implications for ice extent, Nature, 509, 604–607, doi:10.1038/nature13262;   http://www.nature.com/nature/journal/v509/n7502/full/nature13262.html

The propagation of large, storm-generated waves through sea ice has so far not been measured, limiting our understanding of how ocean waves break sea ice. Without improved knowledge of ice breakup, we are unable to understand recent changes, or predict future changes, in Arctic and Antarctic sea ice. Here we show that storm-generated ocean waves propagating through Antarctic sea ice are able to transport enough energy to break sea ice hundreds of kilometres from the ice edge. Our results, which are based on concurrent observations at multiple locations, establish that large waves break sea ice much farther from the ice edge than would be predicted by the commonly assumed exponential decay.... (more)

Shared Humanity

  • Guest
Re: The 2015 melting season
« Reply #1447 on: June 20, 2015, 06:46:19 PM »
And how does your observation of waves on the shallow shoreline of Lake Michigan support your claims that deep ocean, long fetch waves cannot penetrate the ice pack? How do pictures of smooth waters in the Arctic, pictures of anything posted by anyone for that matter, prove anything?

I think we would benefit from reviewing research on the effect of waves on ice. I actually believe there is a  mountain of research on the topic.

ktonine

  • Frazil ice
  • Posts: 363
    • View Profile
  • Liked: 0
  • Likes Given: 0
Re: The 2015 melting season
« Reply #1448 on: June 20, 2015, 06:50:22 PM »
Verge - THINK!  Here's the Healy in late fall in the Beaufort/Chukchi

Now throw some ice floes into the picture.  Disaster!


Do you think any ship's Captain is going to willing ly take his ship into an area with large swells or waves and ice?  That's a recipe for catastrophe.  They'd change course and avoid it at all costs.

Instrumental measurements onshore (seismographs and sonar) can tell us what's happening hundreds of miles away.  You've been pointed to the literature.  No pictures are necessary.

Your idea of 'proof' is sub-optimal.

Shared Humanity

  • Guest
Re: The 2015 melting season
« Reply #1449 on: June 20, 2015, 06:50:53 PM »
A good discussion on the effect of waves going on here.

http://forum.arctic-sea-ice.net/index.php/topic,1288.50.html

And this research is linked on the thread.

http://web.gps.caltech.edu/~tsai/files/Squire_2007.pdf

"It is well-known that ocean waves can penetrate remarkable distances into ice fields, whether they are composed primarily of continuous sea-ice with imperfections such as cracks, leads or pressure ridges or are a concentration of discrete ice floes and ice cakes that are each free to move back and forth. In doing so waves cause the compliant but inelastic sea-ice to flex rhythmically with their passing, they may produce collisions and turbulence, and they are scattered by any heterogeneity— including the edges of the ice floes themselves, with the result that their overall energy density is systematically reduced in a way that discourages the passage of short waves. Waves break up the sea-ice as well; near the seaward periphery of the marginal ice zone, for example, intense seas can pummel the ice into a slurry. Further in, the relentless oscillatory bending may weaken the ice (Langhorne et al., 1998, 1999) and create stresses that lead to fracture, with a concomitant limit to floe size and, under steady state conditions, the evolution of a zonal structure (Squire and Moore, 1980; Peng Lu, personal communication, 2006). Waves may also weaken and rupture continuous sea-ice (Langhorne et al., 2001), causing cracks and fissures to form that may open into leads under divergent winds and currents and thereby contribute to the demise of the ice sheet as a whole."
« Last Edit: June 20, 2015, 07:02:40 PM by Shared Humanity »