The 2015 melting season

[cesium62]

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.

Verg was being quite reasonable and honest.  Quibbling between swell vs wave seems unnecessary.  Jim's photos were clearly out of context.  And Verg did get a few people to post pointers to interesting papers, even if he didn't get the hoped for pictures.

Verg: Illegitimi non carborundum

[Jim Hunt]

Quibbling between swell vs wave seems unnecessary.  Jim's photos were clearly out of context.

Do you want the 5 minute argument, or the full half hour?

In what way were my photos "clearly out of context"? Verg asked to see an "AloftCon of a wave in the arctic Basin" and that's the best I could come up with in a hurry!

[Laurent]

Hycom require a login password now ?
http://www7320.nrlssc.navy.mil/GLBhycomcice1-12/navo/arcticictn_nowcast_anim30d.gif
How to get access ?
HycomARC is fine thought but the new version seemed more accurate...

[mati]

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.

they have buoys in the great lakes that can provide wave height and periodicity:   http://www.ndbc.noaa.gov/station_page.php?station=45007

[seaicesailor]

Hycom require a login password now ?
http://www7320.nrlssc.navy.mil/GLBhycomcice1-12/navo/arcticictn_nowcast_anim30d.gif
How to get access ?
HycomARC is fine thought but the new version seemed more accurate...

Seems temporary to me, no password has even been required until today

[seaicesailor]

I was excusing myself of posting too much, but at least I kept on topic. The wave penetration thing is related to 2015 as much as to 1929

[Lord M Vader]

Interesting to see that the sea ice have lost its grip at the shores in ESS. If conditions start to become more friendly to the Laptev ice there is a decent possibility that the Northern Route will open up early this year.

Also interesting to see the possibility of a weather pattern shift next week with more HP at the Russian side. QED: temporarily or more longer lasting change in that case?

Another thing that I think is quite likely this year if conditions are the right is a "July crash". If so, the record melt rate in July from 2007 with roughly 3 million km² (IJIS numbers!) would blow away. This as Baffin have been slow this year, the coolest air have been located at the fringe areas or where the ice is weakest..

Someone wondered if the ice in the Baffin would possibly survive this melt season. Personally, I would like to say "Yes". As already mentioned, the winter in these parts of North America was very cold and I think I saw a note fo some 8 m thick ice to be seen locally. WRT that the cool weather pattern have continued for a while I don't think it's unlikely that some sea ice, at least at some few places, will have the opportunity to survive this year.

Finally, just something to note: NOAAs latest ONI-index for Niño 3.4 area have been updated with a new version. According to the newer version no official El Niño should have been declared yet... See: http://www.cpc.ncep.noaa.gov/products/analysis_monitoring/ensostuff/ensoyears.shtml With the new estimates this should have been the longest streak without El Niño.

Best, LMV

[jdallen]

Hycom require a login password now ?
http://www7320.nrlssc.navy.mil/GLBhycomcice1-12/navo/arcticictn_nowcast_anim30d.gif
How to get access ?
HycomARC is fine thought but the new version seemed more accurate...

Seems temporary to me, no password has even been required until today

I emailed the web master asking about it.

[Shared Humanity]

So why am I becoming increasingly alarmed about this melt season?

First, I've posted an image of the current SST anomalies. This will serve as context.

The eastern half of North America, both Canada and the U.S., suffered a brutally cold winter. Lets take a look at the regions of the cryosphere which endured this cold weather.

First the CAA:

http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/recent365.anom.region.12.html

Despite the cold winter the CAA melt is 150K square kilometers and 1 month ahead of 2014. I have a hard time understanding this but we have been seeing a growing positive snow cover anomaly in the late fall and early winter. Could deep snow have insulated  the ice from this cold? I would not be  surprised if the Northwest passage opens this year.

What about the Hudson?

http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/recent365.anom.region.13.html

Despite the cold, the Hudson is currently tracking with 2014. Regardless, all of this ice will disappear by the end of the melt season, a 700K drop.

And Baffin Newfoundland?

http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/recent365.anom.region.4.html

Here we see the effects of the cold winter. The sea has 200K square Kilometers more ice than at  this time in 2014. Will some of this ice survive the melt season? I can't imagine much will which means a 600K drop.

As for the Greenland Sea....

http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/recent365.anom.region.5.html

We have been seeing a steady slide in the negative sea ice anomaly for the past 3 months. Given the SST anomaly, this cannot be due to lack of melt. Ice must be exiting the Fram to replace the melted ice. This is not a good thing. If even moderate amounts of ice exit the Fram for most of the melt season, the CAB is in trouble.

And the Barents?

http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/recent365.anom.region.6.html

Looks just like 2014 and with little over 100K, it is no cause for concern.

Not so the Kara.

http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/recent365.anom.region.7.html

The Kara scares the hell out of me. It is 300K less than 2014, a full month ahead. If in the next  month it melts at the rate of last year, you can kiss the Kara sea ice goodbye, ice free by the end of July. With high insolation on ice free water, the refreeze will be late.

And the Laptev?

http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/recent365.anom.region.8.html

It is only while looking at this chart that my heart rate will slow down, 200K more ice than last year.

And the ESS?

http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/recent365.anom.region.9.html

While the ESS got a slow start, melt is accelerating and the ESS is now getting hammered by that low pressure system. If the influx of warm air unzips the ESS it is going to put a lot of heat on the Laptev.

We all know about the Chukchi.

http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/recent365.anom.region.10.html

More than 100K ahead of last year and melt is accelerating. There is no way that the Chukchi is not ice free unless, of course, the Beaufort Gyre pumps a lot of ice into it. Even if it does, SST are so high the ice will likely not survive.

And we better hope the Gyre doesn't move a lot of ice from the Beaufort into the Chukchi.

http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/recent365.anom.region.11.html

The Beaufort has 200K less ice than last year and it is melting fast. My guess is the Chukchi and Beaufort will be ice free at the end of this melt season.

What does this all mean for the Arctic Basin?

http://arctic.atmos.uiuc.edu/cryosphere/IMAGES/recent365.anom.region.1.html

I'm not sure but the rest of this melt season will be riveting.

[TerryM]

IIRC  Dr Francis wrote about the crew & scientists unexpectedly suffering sea sickness from heavy swells very close to the pole in heavy ice late in the season in (2012?).
She said it was the first time any had experienced swells so far from the edge of the pack.


I believe they had headed north from the Laptev Sea in September or October on a Swedish icebreaker.


Terry

[Michael Hauber]

Cryosphere today suggests that the Baffin bay area has never (in 30+years) remained above 100k of ice throughout a melt season, although a couple years in the early 80s came close.

[Jim Hunt]

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 note you have yet to respond to a variety of quotes and references about "the outrageous claim", so here's another "report of wave action 100's of km from the edge" from the literature for you to consider:

http://onlinelibrary.wiley.com/doi/10.1029/2011JC007221/pdf

Large expanses of open water in the Siberian, Laptev, Chukchi, and Beaufort Seas result from declining summer sea ice cover, and consequently introduce long fetch within the Arctic Basin. Strong winds from migratory cyclones coupled with increasing fetch generate large waves which can propagate into the pack ice and break it up. On 06 September 2009, we observed the intrusion of large swells into the multiyear pack ice approximately 250 km from the ice edge.

[Vergent]

Okay, we have a confusion here....In the antarctic ocean, long wavelength waves penetrate hundreds of mines/kilometers.... this is because the water is deep...and in deep waters over thousands of kilometers, long wavelength waves can happen....The arctic however is surrounded by shallow seas. Such waves cannot enter the arctic. People are remembering reading about the Antarctic waves and assuming that it happens in the arctic. Basically, deep water wave dynamics happen when the depth of the water is greater than 1/2 the wavelength of the wave. The arctic is surrounded by shallow water, this does not happen there.... So, to my detractors,...you were right,...but you were in the wrong hemisphere. This is the "Arctic sea Ice" thread. Not the Antarctic sea ice thread.

Verg

edit: http://www.researchgate.net/profile/Susan_Frankenstein2/publication/245293252_Wave-Ice_Interactions_in_Barents_Sea_Marginal_Ice_Zone/links/546df9fe0cf2bc99c21506b9.pdf

[Vergent]

But, I really appreciate being fact checked. I mean that.

Verg

[Frivolousz21]

The ssts in the Southern Chuchki are getting out of hand.

5-8C right up to the ice edge? 

And another thrust of massive WAA underway.

[jdallen]

The ssts in the Southern Chuchki are getting out of hand.

5-8C right up to the ice edge? 

And another thrust of massive WAA underway.

How about... 20C on Wrangel Island...

[Jim Hunt]

Okay, we have a confusion here

I'm not confused Vergent, about waves/seas/swells & north/south at least

But, I really appreciate being fact checked. I mean that.

In which case, what do you make of Asplin et al. (See above). Unfortunately they were on the Amundsen rather than the Healy so AloftCon evidence is sadly lacking, but here's another quote for you:

We progressed through the heavily decayed ice region into a transitional region containing a mix of decayed old and FY sea ice floes, and finally into thick late summer MY pack ice. Using the onboard helicopter to survey the area, we identified a vast MY floe (10 km diameter), to which we intended to moor the ship, and conduct our typical science operations. The ice in this area was much thicker than the heavily decayed FY ice we that we had encountered the previous day to the west. Our helicopter EMI system recorded overall thicknesses of sea ice around station MYI (e.g., mean = 2.0 m, max = 10 m).

As ice teams initially prepared to deploy to the ice, we noticed the appearance of a swell from the ships helicopter deck. Laser data collected during the helicopter EMI survey at station MYI indicated a swell period of 13.5 s, and a wavelength ranging from 200–300 m. Laser data were collected while the helicopter hovered over a large MY ice floe. These data were augmented with three-dimensional dynamic ship positioning data, which revealed approximate ship heave amplitude of 0.4 m, also with a period of 13.5 s. The swell caused the vast MY ice floe nearest the Amundsen to ride up one side of the swell and fracture as it crested the wave peak, creating smaller ice floes of width approximately one half of the wavelength of the swell. In a matter of minutes from the initial onset of swell propagation, all large MY ice floes in the region were fractured in this manner, yielding a new distribution of smaller MY ice floes ranging from 100–150 m in diameter. A helicopter-borne video system recorded this event in still photographs along its flight track which were later combined to create a series of photo mosaics (Figure 3)

On 09 September 2009, we conducted a longitudinal helicopter EMI survey at 72.5 N (Figure 4), and determined the limit of the swell penetration into the pack ice at 72.526 N 134.51 W, a penetration of 350 km. Furthermore, the rotted FY ice margin was heavily fractured, with small floe sizes ranging from 20–50 m in diameter (Figure 4).

Note that this map (extracted from the paper) does not show the Antarctic:

[Frivolousz21]

The ssts in the Southern Chuchki are getting out of hand.

5-8C right up to the ice edge? 

And another thrust of massive WAA underway.

How about... 20C on Wrangel Island...

The heat has been explosive on the Pacific side.

The 850mb temps have been roasting.

Very little cooling at night

Lance MODIS shows the ice crumbling in this region.

It's so warm the SATs think there is 1-3C water on top the ice in the ESS.

That ice has to be melting at warp speed. 


The ESS has huge SST potential.  If we see true open water there by July 1st we could easily see 6-15C ssts over the ESS

[sofouuk]

while I'm happy to go along with the general view that Vergent is wrong about the ability of waves/swell to penetrate the ice field, the original question he was responding to was, to what extent will the presence of fractured ice (rather than consolidated ice) allow waves to penetrate the ice field, and to what extent will any penetration that does occur speed up melting? my initial response on reading the question was 'probably not much, and probably not much' - does anyone have a better answer?

[Neven]

What can happen during stormy, wavy weather is that floes get turned upside down. This underside is much darker due to algae and other micro-organisms living there, and so albedo drops. I've seen footage of this in a short documentary made by those Frenchmen who tried to traverse the Arctic sea ice pack in a catamaran with skis underneath it.

[Gray-Wolf]

I think if Vergent looks up prof barbers report of his 'rotten ice' mission he'll find more reports of waves running through the ice and the dangers sailing though such conditions is ( when it's minus lots and water is being sloshed all over the ship as waves impact!!!). He also notes the damage to a large floe from the waves emerging from ice ( waves formed over on the ESS side of the basin and arriving in Beaufort from under the ice).

Place a piece of cling film in your bath and see if it stops any waves you make..........

[Nick_Naylor]

Another newbie question:

I understand that storm-induced ice migration can cause mixing involving warmer water from the upper thermocline, which would make additional energy available for melting.

I imagine that cyclone size and intensity, ice mobility and location within the arctic are all important factors in whether heat from the depths reaches the ice.

Is there a good understanding on what conditions are necessary for this to occur?

There's quite a lot of information here, but much of it is over my head:
http://psc.apl.washington.edu/HLD/PeraltaFerrizandWoodgateArcticMixedLayerProperties_inpressPiODec2014.pdf

[Vergent]

Jim Hunt,

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

In what way does a remarkable observation of a surge in 2009 penetrating the arctic ice cap refute the assertion that "in general" this does not happen?

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

Does it support the assertion that there are "continuous reports" of such events? If you were grading a test, which of these statements would you grade as true, and which are false?

Verg

[mati]

Cryosphere today suggests that the Baffin bay area has never (in 30+years) remained above 100k of ice throughout a melt season, although a couple years in the early 80s came close.

Baffin Bay has a very strong current moving the ice to the south.
See the Hall expedition
http://www.nytimes.com/2006/02/19/books/review/19barcott.html?pagewanted=print

[Nightvid Cole]

This source seems to suggest quite significant temp anomalies over the coming week in the Arctic. It seems quite extraordinary considering that the normal temps for late June over the Arctic Ocean proper should be pegged to the freezing mark.

[Nightvid Cole]

MODIS corroborates the snow forecasts and agrees that surface melt is well ahead of the same date last year (first image is 6/21/2015, second image is 6/21/2014):

[nukefix]

I do not see why North Atlantic storms could not generate huge swells in areas of sufficient depth & fetch, which could then penetrate deep into the Arctic basin.

[ChrisReynolds]

Hycom require a login password now ?
http://www7320.nrlssc.navy.mil/GLBhycomcice1-12/navo/arcticictn_nowcast_anim30d.gif
How to get access ?
HycomARC is fine thought but the new version seemed more accurate...

Seems temporary to me, no password has even been required until today

I emailed the web master asking about it.

It started from Saturday, maybe maintenance work is ongoing...

Let us know the result will you?

[TerryM]

Verg
When Dr. Francis wrote of large swells, far into the ice pack, she specifically mentioned that this was a unique experience both for her and the icebreaker's crew.
I'd venture to say that swells, if not waves, can penetrate far into broken ice fields, but that this requires an unusual combination of weather and ice conditions.
Long fetches of ice free waters abuting compact but fractured ice fields, may limit the phenomenon to late in the melt season when the ice edge has pulled far enough away from the coasts, for the swells to build.
I've searched in vain for the article but recall Francis writing of heavy fog, loose ice and Polar Stern? rolling about due to the swells.
Terry

[Lord M Vader]

ECMWF 12z run is very interesting from +168 hours and onward in "fantasyland".. If that one really materializes it would certainly mean a good start for "July crash"

Just to wait and see...

//LMV

[johnm33]

My 2c, It seems to me that when you have broken ice thats mobile and powerful persistent winds the very movement of the ice will form a wave ahead and a trough behind and I thought that's what showed up in this http://www7320.nrlssc.navy.mil/hycomARC/beaufort.html [still available at time of writing] in various ways due to the recent cyclone. Once the swell is established the pressure wave travels through the sea creating a wave/ trough differential in the low meters, generating transverse waves as it passes [ fracturing the ice in a complex 'diamond' pattern] until it reaches the continental shelf where you find some rebound and some smaller waves which break up and are broken by the peripheral ice. A wave formed in shallow water will cause the water/ice to move out of it's way but in deep water it will propogate into the depths and cause more complex oscilations as it imposes itself on the various density/salinity layers, does it speed up in the denser layers?, but they will be below the level of continental shelf and will carry and sustain far more energy than the surface waters and will not be attenuated so easily by them.
If you can find it 'The secret life of waves' by david malone is worth a veiwing.

[Neven]

ECMWF 12z run is very interesting from +168 hours and onward in "fantasyland".. If that one really materializes it would certainly mean a good start for "July crash"

Just to wait and see...

//LMV

Yes, that looks like an ideal set-up for a sea ice massacre, but still very far out.

[Michael Hauber]

ECM and GFS seem to forecast almost the opposite at 7 days.  If GFS is correct then ice is going to be transported into the Laptev sea for the rest of the week and we may see no significant open water in the Laptev at the start of July which has not happened since 2008.

[jdallen]

ECM and GFS seem to forecast almost the opposite at 7 days.  If GFS is correct then ice is going to be transported into the Laptev sea for the rest of the week and we may see no significant open water in the Laptev at the start of July which has not happened since 2008.

I'm not sure it will help - it means open water elsewhere, and the ice entering the Laptev is thin and will still melt out... in fact, it will be getting shoved into areas close to the continent and the absolutely infernal heat that's been getting blown out of it into the Arctic ocean proper.

direct transfer of heat from atmosphere to Ice is a minor contributor to melt, normally, but quantity (extraordinary temperatures) has its own quality.

Add melt ponds and sunlight, and by August we'll still have a "Laptev Bite".

[Nightvid Cole]

ECM and GFS seem to forecast almost the opposite at 7 days.  If GFS is correct then ice is going to be transported into the Laptev sea for the rest of the week and we may see no significant open water in the Laptev at the start of July which has not happened since 2008.

If ECM and GFS are totally opposite, perhaps it's just too far out!

[helorime]

48F (9C) at both Barrow and Alert.  Hot in Alaska and eastern Siberia, warm all around the arctic.  There must be a lot of melting going on right now.

[cesium62]

Quibbling between swell vs wave seems unnecessary.  Jim's photos were clearly out of context.

Do you want the 5 minute argument, or the full half hour?

In what way were my photos "clearly out of context"? Verg asked to see an "AloftCon of a wave in the arctic Basin" and that's the best I could come up with in a hurry!

We better go for the full half hour.

A "wave in the arctic basin" clearly means one that is not close to shore, and it was pretty clear that Verg was asking for a wave/swell travelling through an ice field.  I enjoy your photos, and I don't mind you being off topic.  I just think various people are inappropriately picking on Verg with respect to this particular sub-thread.

Edit:  The top picture states that it is a picture of Barrow, Alaska, which is not in the arctic basin.  The bottom picture is also not in the arctic basin: https://www.google.com/maps/place/67%C2%B000'00.0%22N+168%C2%B010'48.0%22W/@67,-168.18,7z/data=!4m2!3m1!1s0x0:0x0

[ktonine]

Verge,

I can't speak for anyone other than myself, but I find it a bit arrogant to assume that *I* was confused.

I was not.

You may not want to admit you're wrong, but both waves and swells can penetrate the arctic ice fields. Swells will travel much further into a solid pack, but even waves can travel dozens, if not hundreds, of kilometers into loose ice.

This has been corroborated by seismographs, sonar, and satellite.  Indeed, just look at the references in this paper to see just how long all of this has been known. Estimates of ocean wave heights and attenuation in sea ice using the SAR wave mode on Sentinel-1A

Almost since the inception of satellite data retrieval over the arctic the effects of swells on the ice pack were noticed and had to be accounted for : "Lyzenga et al.[1985]  had  already  observed  that  in ice-covered conditions the distortion of SAR images by swell  orbital  velocities,  known  as  the  velocity  bunching,  is  generally  constructive  and  yields  a  wavy  pattern." 

So, no, I'm not confused.  Both waves and swells can penetrate the ice-pack in the Arctic.  This has been noted and studied in the literature going back to at least Peter Wadhams in the 1970s. This has been seen using various forms of instrumentation; including sonar, seismographs, and satellites. 

[sedziobs]

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, 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.

My reply was meant to re-direct the discussion to what Chris and Jim had posted, but it had the effect of a distracting attack on Vergent.  This is my fault, as claims of dishonesty are indeed an attack.  The attack was supposed to be directed only at the false binary presented, since I believed it ignored Jim and Chris' arguments.  However, my poor choice of words attacked Vergent himelf unnecessarily, and for that I am sorry.

Verg, if you so choose, you may have the last word on this issue with me.  I did not and still do not intend to have my opinions distract from the 2015 melting season thread.

[Michael Hauber]

Okay, we have a confusion here....In the antarctic ocean, long wavelength waves penetrate hundreds of mines/kilometers.... this is because the water is deep...and in deep waters over thousands of kilometers, long wavelength waves can happen....The arctic however is surrounded by shallow seas. Such waves cannot enter the arctic. People are remembering reading about the Antarctic waves and assuming that it happens in the arctic. Basically, deep water wave dynamics happen when the depth of the water is greater than 1/2 the wavelength of the wave. The arctic is surrounded by shallow water, this does not happen there.... So, to my detractors,...you were right,...but you were in the wrong hemisphere. This is the "Arctic sea Ice" thread. Not the Antarctic sea ice thread.

Verg

The average depth of the Barents shelf is 230 meters.  Definitely shallow on world ocean basis.  But for waves, deep water is anything above half the wavelength of a wave.  For a 15 meter high swell this amounts to just over 100 meters.  Given that some of the Barents shelf will be less than 230m, but that it is generally reasonably flat, (and the Fram Strait is deeper) I don't think anything but the very largest Atlantic ocean swells are going to be blocked from entering the Arctic Ocean.  Further a fully developed swell of 4 meters can be generated in 500km of open ocean, which is pretty easy to come by within the Arctic by the end of the melt season.

[Vergent]

Sorry to interject science into the discussion. Here is a table of the relationship between wind speed and wave period and wavelength:

https://en.wikipedia.org/wiki/Swell_(ocean)

[hide]Conditions Necessary for a Fully Developed Sea at Given Wind Speeds, and the Parameters of the Resulting Waves
Wind Conditions   Wave Size
Wind Speed in One Direction   Fetch   Wind Duration   Average Height   Average Wavelength   Average Period and Speed
19 km/h (12 mph)   19 km (12 mi)   2 h   0.27 m (0.89 ft)   8.5 m (28 ft)   3.0 s, 2.8 m/s (9.3 ft/s)
37 km/h (23 mph)   139 km (86 mi)   10 h   1.5 m (4.9 ft)   33.8 m (111 ft)   5.7 s, 5.9 m/s (19.5 ft/s)
56 km/h (35 mph)   518 km (322 mi)   23 h   4.1 m (13 ft)   76.5 m (251 ft)   8.6 s, 8.9 m/s (29.2 ft/s)
74 km/h (46 mph)   1,313 km (816 mi)   42 h   8.5 m (28 ft)   136 m (446 ft)   11.4 s, 11.9 m/s (39.1 ft/s)
92 km/h (57 mph)   2,627 km (1,632 mi)   69 h   14.8 m (49 ft)   212.2 m (696 ft)   14.3 s, 14.8 m/s (48.7 ft/s)

So, it takes 92 km/hr to make waves with a period greater than 13 seconds.



http://onlinelibrary.wiley.com/doi/10.1029/2009GL040676/full

Here we see the attenuation of waves by ice. Waves with periods of 13 seconds attenuate by a factor of  1/1,000,000 in fifty kilometers. That means a ten meter wave would be a 0.01mm( 100 000 angstroms ) ripple at that distance. Do you really want to call 0.01 mm a wave?

Verg


edit; spelling

[Lord M Vader]

Neven: GFS 00z is no good news at all for the sea ice from about +132 hours!!!

//LMV

[jdallen]

We will see. More reliable - temperatures over the Chukchi, ESS and Beaufort are just absurdly bad for the next 24-48 hours.

[Frivolousz21]

The 00z euro goes nuclear after day 5.

Looking like this will be another 2008. With higher volume in Sept this year.

[F.Tnioli]

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.

This post of mine was in response to the forecast of ice drift for 22th June, which was showing large movement of ice "away" from ESS shore this very day. When ice goes away, water is what remains, i guess. I am sorry if my guess on this is wrong; and/or if a bit poetic way i expressed it - is inappropriate.

...
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. ...

Side remark. Apologies for noobishness, but i humbly suspect that plate tectonics certainly can exceed any wave power. That tsunami from Japan you mentioned, which broke some shelves in Antarctica? A mere echo of quite "usual" in terms of decades quake, containing but a small fracture of its energy. And, of course, hurricanes are certainly in the league, too...

[Frivolousz21]

The 00z GFS and euro both agree now.


The one week SST change is incredible.

[Neven]

The one week SST change is incredible.

Indeed, and like I wrote in ASI 2015 update 3 on the blog:

When it comes to sea surface temperatures (SST) there have been some massive changes compared to two weeks ago, where dark and even pinkish red have been showing up in the Kara Sea, but dramatically more so in the Bering Strait and Chukchi Sea:



The difference - on the Pacific side - with 2012, 2013 and 2014 around this time is HUGE (mind you, I use Caps Lock sparingly). It seems all that heat in the North Pacific, combined with open skies and high land temperatures, is really making itself felt on the Pacific side this year.

And the following conclusion:

The question is what effect this onslaught from the Pacific will have. And it's a crucial question - one that I already asked several weeks ago in the conclusion of the 2014/2015 Winter analysis -, as this region contains large amounts of multi-year ice that was transported there during the past winter (image hasn't been updated for over a month):



My initial question: Will the multi-year ice that has been transported from the Central Arctic into the Beaufort and Chukchi Sea form a barrier that can withstand whatever the melting season throws at it? Or will it melt, with consequent volume losses?

Some models are forecasting a massive decrease in thickness on the Pacific side of the Arctic (see this blog post by Chris Reynolds). Although I'm generally wary of these forecasts, the changes are very pronounced and could certainly come about, given the current build-up of melting momentum in that part of the Arctic. At the same time weather conditions aren't all that conducive to large-scale melting, and thus it will take some time for any effect to become apparent.

Either way, I still believe 2015 will surpass rebound years 2013 and 2014, but whether it can come close to the top 3 years (2007, 2011 and 2012) is very much up in the air. With current developments on the Siberian side, the Northern Sea Route could open early this year, and the ice blocking the Northwest Passage has also taken quite a hit recently. So, what's it going to be? More on all of that in two weeks.

Enjoy the Arctic sea ice, it's the only Arctic sea ice you've got.

[gerrit]

What is coming through the Bering Straight?

I'm sure most of us have noticed how warm it is in the Northern Pacific, and that there has been North-blowing wind anomalies for quite a while now. While it is understandable that most of this forum's focus is on atmospheric conditions, we shouldn't forget the influences of this water current, both in terms of heat import and halocline stability (or, in this case, maybe instability...)

Normally, anywhere between 1 and 6 x 10^20 J is added to the arctic through this current. If this heat reaches the ice, it is enough to melt 1800 cubic km of it. But my guess is that this year it might be much higher, so it is maybe worth keeping an eye on it in our guesstimations.

It is of course also linked to Fram export, which we know has also been a bit on the high side so far this season.

http://psc.apl.washington.edu/HLD/Bstrait/bstrait.html
http://arctic.cbl.umces.edu/book_chapters_and_info/Ch%207%20Clement-Kinney%20formatted.pdf

[Michael Hauber]

So, it takes 92 km/hr to make waves with a period greater than 13 seconds.

It takes 92km/hr to make waves with an average period of 13 seconds.  There will be a range of periods and some of these will be greater than the average.

Here we see the attenuation of waves by ice. Waves with periods of 13 seconds attenuate by a factor of  1/1,000,000 in fifty kilometers. That means a ten meter wave would be a 0.01mm( 100 000 angstroms ) ripple at that distance. Do you really want to call 0.01 mm a wave?

All the short period swells, which may be the vast majority of the individual waves will attenuate quickly, but the longer period swells will still exist and your chart shows they penetrate hundreds of kilometres.  I don't know exactly how much longer than the average period the longer period swells can get, but the fact that a researcher shows an attenuation chart for waves with periods 13 to 35 seconds in the Arctic suggests that enough waves with this period exist to make generating a chart worth while.

[Michael Hauber]

This post of mine was in response to the forecast of ice drift for 22th June, which was showing large movement of ice "away" from ESS shore this very day. When ice goes away, water is what remains, i guess. I am sorry if my guess on this is wrong; and/or if a bit poetic way i expressed it - is inappropriate.

Basically because some of the ice is stuck to bottom of shallow ocean, only some of it moves away. 

I have no problem at all with the way you expressed it.  I don't think anyone should be afraid of being wrong.  But it is always good to remember that no matter how convinced I am of an opinion, it is always possible I will be wrong, and it is good to try and allow for this possibility by being polite, and considering whether I can replace the definites in my statement with maybes.  Even though I regularly forget....