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6roucho

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Re: The 2016/2017 freezing season
« Reply #1300 on: December 10, 2016, 01:12:41 AM »
Which highlights the importance of the amount of multi-year ice that is thick through compaction or ridging.

jai mitchell

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Re: The 2016/2017 freezing season
« Reply #1301 on: December 10, 2016, 02:03:56 AM »
so how much more time do folks think we really have at this point?

Apparently some are still holding onto AR4 models with RCP 8.5 emissions leading to a September Ice free (< 1X10^6 km^3) September minimum around 2065 at the earliest and >2100 at the latest.

(can you believe that????:'(

(makes you wonder if they are on the Koch brother's payroll)
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Re: The 2016/2017 freezing season
« Reply #1302 on: December 10, 2016, 02:18:42 AM »
glad to see widely spread consensus in assesment of the current situation is taking over, even though the obvious reasons for that are nothing to be glad about. 

a certain amount of consensus and resulting joint efforts will sooner or later be needed to cut the peaks of the most extreme effects while i strongly suspect that we better start to think about how deal with the inevitable than about how to avoid it ( the inevitable )

i cannot see any reasonable scenario and/or means that would let us kill the downward spiral we're currently in and then i as well would propose to consider the possibility that not all effects of global warming will be outright bad. it will be fatal for some species, regions etc. but provide an evironment to proper for others.

one of the "solutions" will certainly be to thoroughly look into local effects and make decsions as to what can be protected and what has to be abandoned and where new settlement and building should be avoided (prohibited) things will change and yes changes are mostly seen as a threat but not necessarily have to be negative.

i hope that this did not sound like all is well, i just say that solutions never come through paralized fear frozen states but from analysis, decision taking and a good portion of optimism as compared to hopelessness.

logicmanPatrick

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Re: The 2016/2017 freezing season
« Reply #1303 on: December 10, 2016, 03:53:15 AM »
RE; Tigertown's post -
After a long search, Barber's ice breaker finally found a 16-km (10-mile) wide floe of multiyear ice that was around 6 to 8 meters (20-26 feet) thick. But as the crew watched, the floe was hit by a series of waves, and disintegrated in five minutes.

Waves, whether wind or tide - waves, can certainly disintegrate ice very rapidly.

Quote
the most formidable fields yield to the slightest grown swell, and become disrupted into thousands of pieces; and ice of only a few weeks growth, on being assailed by a turbulent sea, is broken and annihilated with incredible celerity. Bay-ice, indeed, which for weeks has been an increasing pest to the whale-fisher, is sometimes removed in the space of a few hours. The destruction is in many cases so rapid, that to an un-experienced observer, the occurrence seems incredible, and rather an illusion of fancy, than a matter of fact. Suppose a ship immoveably fixed in bay-ice, and not the smallest opening to be seen : after a lapse of time sufficient only for a moderate repose,  imagine a person rising from his bed, — when, behold, the insurmountable obstacle has vanished !

Exerpted from An Account of the Arctic Regions,
W. SCORESBY Jtm. F.R.S.E.
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Re: The 2016/2017 freezing season
« Reply #1304 on: December 10, 2016, 04:50:07 AM »
thank you lmP .. Scoresby's description of the ice disappearing makes me even more certain that next year we will be seeing more open water and for longer .. than those scientists referred to above expected to see in their lifetimes . Madness  !
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aslan

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Re: The 2016/2017 freezing season
« Reply #1305 on: December 10, 2016, 11:28:43 AM »
Quote
using a flawed metric (extent instead of volume) and ignoring aerosol emissions do not have any impact, she grossly underestimates the projection of future sea ice loss. laughable (if it wasn't so deadly important) assertion that it would take ANY MORE emissions from today to cause an ice free September minimum.  (hint: it won't). Graphic is gross.
Thanks, Jai. That and more needs to be said. The article is not even up to forum standards. The gimmick though was well-intentioned: personal footprint <--> lost ice. However it is way too late in the day for mickey-mouse mitigation like (voluntary) air travel offsets to begin in 2027 etc.

Yep, and they failed to consider the inertia of the system and the fact that we are way out of balance. Reaching  a summer free sea ice is only a matter of time now, and even a matter of short time (a few years probably).

For Siberia, it was an extraordinary heat wave, bringing record heat and above freezing temperatures. SYNOPs are totally crazy, and are more like SYNOPs from a stormy day in Ireland than SYNOPs in Arctic Coast, far to the North of Siberia.

Omolon broke its December record, old value was set in 2010:

http://pogodaiklimat.ru/monitor.php?id=25428

And farther to the North, locally it was feeling more like Ireland Coast than Arctic Coast:

http://ogimet.com/cgi-bin/gsynres?ind=21978&decoded=yes&ndays=10&ano=2016&mes=12&day10&hora=00

Above freezing during 39 hours (!!!) and gusts up to ~145 kph... Ice melt is absolutly certain in this conditions. Even around the Kolyma, more famous for its gulags, its harsh winters, its wolves, its firs, than its sea resorts; it was above freezing:

http://ogimet.com/cgi-bin/gsynres?ind=25121&ano=2016&mes=12&day=10&hora=6&min=0&ndays=30

Warmest temperatures ever for December... I didn't check in details the data, and there is some gaps, but for example here at Buhta Ambarcik temperatures blow off the roof also:

http://ogimet.com/cgi-bin/gsynres?ind=25034&decoded=yes&ndays=20&ano=2016&mes=12&day=10&hora=06

The highest min for this station until now was probably a -4.7°C reading the 1st of December in 1973 (records go back to around 1948 - 1950). Now, the highest min is 0.7°C! Even acknowledging there is some gaps in the data, it is virtually certain it is the first time this station is above freezing in December for more than a day... The highest temp in December was until now a 3.6°C reading in 1966. Unfortunately, the Tx is lacking in the SYNOP, but the new Tx is at least 4.2°C since yesterday. Depending on the period and the method used for calculating the daily mean, this station register a Tm of around 2°C the 09th of December, 30°C above 1981-2010 normal and breaking the warmest Tm of -1.5°C set in 1996 (the 23th)... And it is the same elsewhere along the coast. Nearer to the Pacific (like in Pevek Apapelgino) no record was set, warm moist air coming from Ocean being able time to times to reach the Siberia. But for the Kolyma region, deep interior of Siberia, and Arctic Ocean, it was an extraordinary heat wave. And this pattern is set to continue according to models:

http://www.wetterzentrale.de/maps/ECMOPNH00_120_2.png
« Last Edit: December 10, 2016, 11:43:34 AM by aslan »

Jim Hunt

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Re: The 2016/2017 freezing season
« Reply #1306 on: December 10, 2016, 01:13:06 PM »
Waves, whether wind or tide - waves, can certainly disintegrate ice very rapidly.

An extract from David Barber's paper on the topic:

Quote
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.
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oren

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Re: The 2016/2017 freezing season
« Reply #1307 on: December 10, 2016, 02:08:14 PM »
I had an extremely prominent climate scientist relate to me recently that he thought that any advanced models that held a possibility of an "ice-free" September in the arctic within the next 2 decades was stretching it.  He is at UW and directs a major program there with a product that we all use. 

He stated to me unequivocally that there is NO indication that there will be an ice free September within the next 7 years, he was quite sure of himself.
The good news in this sad story is that once the arctic does reach an ice-free September, or even a shockingly low min, this scientist and others of the same mindset might be jolted. Although I doubt any serious action will ever take place until all points of no return are well past.

Gray-Wolf

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Re: The 2016/2017 freezing season
« Reply #1308 on: December 10, 2016, 02:30:42 PM »
I had an extremely prominent climate scientist relate to me recently that he thought that any advanced models that held a possibility of an "ice-free" September in the arctic within the next 2 decades was stretching it.  He is at UW and directs a major program there with a product that we all use. 

He stated to me unequivocally that there is NO indication that there will be an ice free September within the next 7 years, he was quite sure of himself.
The good news in this sad story is that once the arctic does reach an ice-free September, or even a shockingly low min, this scientist and others of the same mindset might be jolted. Although I doubt any serious action will ever take place until all points of no return are well past.
I'd rather hope this comment was culled well before we went into this re-freeze season and so may well be reassessing their stance on the back of new data?
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ktonine

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Re: The 2016/2017 freezing season
« Reply #1309 on: December 10, 2016, 04:29:34 PM »

Accumulated Freezing Degree Days N80 thru Dec 09, 2016:

Climatology: 1600.85
2016:             828.34
Anomaly:      -772.51




Implied new ice thickness to date:
Per Lebedev:
Climo: 1.189 m
2016:   0.806 m

Per Billelo
Climo:  0.960 m
2016:    0.655 m

A-Team

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Re: The 2016/2017 freezing season
« Reply #1310 on: December 10, 2016, 04:46:28 PM »
The Chukchi Sea hit its low water mark (maximal refreeze extent) on Dec 3rd; open water has since increased somewhat (16%) by the 9th.

Did someone in the scientific community predict this? Surely then they know too what it will look like at the winter equinox. And the SMOS ice thickness distribution on the first of May, so helpful. If they could only share their knowledge for ice conditions 1, 2, 3, ... 34 years out to 2050, it would spare us time wasted in actually watching reality unfold.

Amazing that no one knows what will happen tomorrow, next week, next month, next spring, or next fall, or next year, or the year after but yet can speak with great confidence (and zero accountability) about 34-84 years out. Something to do with 'climate', a conceptual Arctic Ocean freed from the nuisance of runaway weather and inconvenient feedbacks, as determined by building out trends in no-longer-applicable equable historic data from implausibly low hypothetical future emissions. (I've not been able to tunnel into their parallel universe as yet.)

Frankly, we need to redeploy these clowns to research more along the lines of what J Francis has been doing: looking at near-term mid-latitude consequences of unpleasant but increasingly plausible early melt-out scenarios. Great recent interview in yale360: http://tinyurl.com/zdjhpoj

In the 25 Nov-09 Dec 2016 time series, blue numbers show relative areas of open water (taken as 0% sea ice concentration from UHH AMSR2 large resolution); black numbers add in dodgy marginal ice (taken as sea ice concentration between 0-20%); the gold numbers measure ice consolidation (sea ice concentration between 80-100%). The animation ends with a flash comparison of the 3rd to the 9th.

Weather artifacts are largely washed out in AMSR2 time series; other algorithms applied to other data from other instruments on other satellites show excellent agreement (previous posts). The real issue is correcting current ice categorizations with ground-truthed Sentinel 1A whose 20 m resolution, unlike 40 km x 40 km pixels, is dimensionally commensurate with floes, leads, ridges and frazil (subsequent post).
« Last Edit: December 10, 2016, 05:05:47 PM by A-Team »

bbr2314

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Re: The 2016/2017 freezing season
« Reply #1311 on: December 10, 2016, 04:49:07 PM »
That is very troubling, and worse still to come with the plumes of heat entering that side of the Arctic over the next 10+ days.

oren

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Re: The 2016/2017 freezing season
« Reply #1312 on: December 10, 2016, 05:00:00 PM »
Did someone in the scientific community predict this? Surely then they know too what it will look like at the winter equinox. And the SMOS ice thickness distribution on the first of May, so helpful. If they could only share their knowledge for ice conditions 1, 2, 3, ... 34 years out to 2050, it would spare us time wasted in actually watching reality unfold.
Surely no such detailed predictions will be posted, or they might be shown as wrong very soon by reality. It's better to make general predictions than to be embarrassed by "details".

Tigertown

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Re: The 2016/2017 freezing season
« Reply #1313 on: December 10, 2016, 05:07:08 PM »
That is very troubling, and worse still to come with the plumes of heat entering that side of the Arctic over the next 10+ days.
Causing this.
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bbr2314

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Re: The 2016/2017 freezing season
« Reply #1314 on: December 10, 2016, 05:09:41 PM »
and another pulse at D10  :o



that is a crazy connection to the mid/tropical latitudes





i wonder, with those temps and that wind (in 940s/950s potentially in Chukchi), how bad will impact be on the ice? seems like it is going to see maaaaaajor wave action


jai mitchell

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Re: The 2016/2017 freezing season
« Reply #1315 on: December 10, 2016, 05:14:33 PM »
The Chukchi Sea hit its low water mark (maximal refreeze extent) on Dec 3rd; open water has since increased somewhat (16%) by the 9th.

Did someone in the scientific community predict this? Surely then they know too what it will look like at the winter equinox. And the SMOS ice thickness distribution on the first of May, so helpful. If they could only share their knowledge for ice conditions 1, 2, 3, ... 34 years out to 2050, it would spare us time wasted in actually watching reality unfold.

http://www.cesm.ucar.edu/working_groups/Polar/presentations/2010/maslowski.pdf

Note: Maslowski's models are based on ocean heat influx.  the reality is far more advanced heat intrusion from atmospheric system changes.
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Tigertown

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Re: The 2016/2017 freezing season
« Reply #1316 on: December 10, 2016, 05:34:16 PM »

that is a crazy connection to the mid/tropical latitudes

i wonder, with those temps and that wind (in 940s/950s potentially in Chukchi), how bad will impact be on the ice? seems like it is going to see maaaaaajor wave action
I think it may just be worse than anyone realized going into this season.
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magnamentis

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Re: The 2016/2017 freezing season
« Reply #1317 on: December 10, 2016, 06:14:21 PM »
glad to see widely spread consensus in assesment of the current situation is taking over, even though the obvious reasons for that are nothing to be glad about. 

a certain amount of consensus and resulting joint efforts will sooner or later be needed to cut the peaks of the most extreme effects while i strongly suspect that we better start to think about how deal with the inevitable than about how to avoid it ( the inevitable )

The way you put it Magnamentis it seems nature is now reaching a consensus with your expectations. And the models, as soon as they align with your consensus, they start to make sense. Until then, they are just "invalid"... right? Like PIOMAS used to.
I don't give a r. F. about your consensus.

i'll carefully consider your thought. indeed it wouldn't be good if that implied motive were true :-)

without the f.. word at the end it would be an even more valuable contribution to
check motives and reasons whether they're right or wrong and of course i'm sorry
if that well meant expression of joy as to the public opinion coming more and more to
terms did offend anyone while one get's used to it over decades and millennia of history.

last but not least if indeed it were true that nature reached a consensus with my expectation that would only mean that my expectations (predictions) were spot on and while the motive to talk to be right is no good at all the fact itself that it's like that is nothing i can see anything wrong in it. after all it only matters what's correct and not who was correct, except perhaps when it comes to long-term credibility but that's only important for those who have either pecuniary interests or decisions taking influence (power) not for a mere interested individual.

cheers
« Last Edit: December 10, 2016, 06:26:43 PM by magnamentis »

FishOutofWater

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Re: The 2016/2017 freezing season
« Reply #1318 on: December 10, 2016, 07:02:39 PM »
The predictions of the GFS model have become unstable for more than 3 or 4 days out. The ECMWF may be a little better but the models have big time troubles dealing with blocking highs. My head has been spinning watching the different model outputs over the past week.

We are dealing with a situation of unprecedented ocean heat so far north on both the Pacific and Atlantic sides, in the month of December. It's spinning up the storms, pushing more water vapor into atmospheric mid levels where the clouds and water vapor block radiant heat loss. The intense storms, tracking from south to north into the Arctic drive huge wave fetches over the Atlantic into the Arctic. The recent madness over Siberia couldn't generate a fetch but winds were so strong and warm that the ice was driven back from the east Siberian shores.

We're getting feedback on top of feedback and it's giving the weather models hell over forecasts a week out. All these old timers and their ice forecasts are lost at sea. They mean well, but they are adrift.

I've been watching weather since I was a little kid. Although I studied geochemistry in grad school, I went to weather map discussions every day at lunch hour so I have been looking at synoptic weather maps for over 40 years. I have seen nothing like the madness we are seeing now.

The latest GFS runs have crazy deep lows heading into the Arctic. Maybe they won't verify, but the heat we just saw hit Siberia was off the charts. The retreat of sea ice in the Chuchki sea from 3Dec to 9Dec (figures below) was shocking. There's enough open water in the Chuchki sea now so that waves are mixing the water bringing up heat from below. Deep convection off the Chuchki shelf into the Beaufort sea may be enhanced by this mixing. If anyone has ever seen so much open water from the Bering strait pushing into the Arctic in the second week of December, I would like to know. I don't remember seeing anything like this.

Anybody who has confidence in their predictions now is either a liar or a fool, in my opinion. The whole ice/ocean/atmosphere system is changing too fast and has become unstable.

I continue to watch with amazement and fear. The liars and fools are in charge.

meddoc

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Re: The 2016/2017 freezing season
« Reply #1319 on: December 10, 2016, 08:48:31 PM »
I guess all current models can be thrown out of the window. We see geological events plying out in real- time.

jai mitchell

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Re: The 2016/2017 freezing season
« Reply #1320 on: December 10, 2016, 10:01:15 PM »
Anybody who has confidence in their predictions now is either a liar or a fool, in my opinion. The whole ice/ocean/atmosphere system is changing too fast and has become unstable.

Indeed, though the trend is unmistakable.
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6roucho

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Re: The 2016/2017 freezing season
« Reply #1321 on: December 10, 2016, 10:03:54 PM »
One person who must be watching this with interest is Peter Wadhams. It looks as though physics may wish to have the final say over what is possible in physics.

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Re: The 2016/2017 freezing season
« Reply #1322 on: December 11, 2016, 04:39:15 PM »
Following a suggestion by ZackL, a mostly cloud-free VIIRS* image is shown below for 11 Dec 16 at various scales and indexed color (from ImageJ choices). It is a vast improvement in resolution and ice detail over any of our sea ice products. The Bering Strait is 85 km wide; at full resolution that is afforded 115 pixels.

* https://en.wikipedia.org/wiki/Visible_Infrared_Imaging_Radiometer_Suite

The first animation shows the scale relative to UHH 3.125km sea ice concentration classification. One has to wonder what ice depiction bins in Piomas, Smos, AMSR2, IJIS, Hycom etc really mean relative to what is physically down there. Only the final animation is at full posted resolution -- it shows the putative isolated ice block in the central Chukchi also seen in AMSR2. The satellite image is dated to the minute but the AMSR2 composite only to the day; as the ice moves, comparisons are qualified.

http://feeder.gina.alaska.edu/snpp-gina-alaska-i05-images/2016_12_11_12_47_jd346

http://feeder.gina.alaska.edu/media/W1siZiIsIjIwMTYvMTIvMTEvMDRfNTJfMTlfODQ4X25wcC4xNjM0Ni4xMjQ3X0ROQi5qcGciXV0/npp.16346.1247_DNB.jpg
« Last Edit: December 12, 2016, 04:37:16 PM by A-Team »

FishOutofWater

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Re: The 2016/2017 freezing season
« Reply #1323 on: December 11, 2016, 06:33:17 PM »
The only year in the record with less ice in the Chukchi sea for 10Dec was 2007 according to Andrew Slater's maps. In the summer of 2007 strong winds from the Pacific to the Atlantic side of the Arctic ocean drove an unprecedented flow of water into the Arctic from the Pacific side. The result of that influx of Pacific water was a large amount of open water in the Chukchi into the first few weeks of December and a high extent of sea ice on the Atlantic side.

This year huge areas of open water in the Arctic seas are on both sides of the Arctic ocean, something we have never seen before.

As usual, stunning visuals, A-Team. Clearly, VIRS has untapped potential for studying sea ice.

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Re: The 2016/2017 freezing season
« Reply #1324 on: December 11, 2016, 08:49:48 PM »
A torrid time ahead too for the beleaguered Barents Sea according to today's ECMWF 12Z run. After day 4 positive 850 hPa temp anomalies edge eastward from Svalbard. The anomalies increase to +16 by day 10, as mild long fetch SW lies are fed north over the top of the big Euro high.


bbr2314

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Re: The 2016/2017 freezing season
« Reply #1325 on: December 11, 2016, 10:03:25 PM »
Models favoring very deep lows approaching Fram...


Iain

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Re: The 2016/2017 freezing season
« Reply #1326 on: December 11, 2016, 10:35:23 PM »
Ekman transport and wave action mixing has been mentioned a lot recently.

My understanding is that Ekman pumping is where wave action causes an offshore surface current which in turn draws warmer saltier subsurface water up . So it’s effect on the CAB must be small, as it only apparent near the coasts.

Also wave action is an elliptical motion of the water on the surface with a second, third…n elliptical motion below, but the amount of motion drops off dramatically with depth.
So a 1m wave would only have a significant effect down to around 3m
A 10 m wave (much less frequent) would have the same effect much deeper.
But the cold less saline layer in the CAB is c. 50m deep, so only very rare large waves would have a mixing effect into the warmer layer.

So the ice is relatively safe from Ekman and surface wave mixing.
Or can anyone point to a ref which contradicts the above?

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Re: The 2016/2017 freezing season
« Reply #1327 on: December 11, 2016, 11:15:23 PM »
 Also, the thicker ice dampens the waves. At the current time, the ice not being as thick, the waves are more of a concern.
There is a thread with good info on here.
http://forum.arctic-sea-ice.net/index.php/topic,1222.0.html

Edit: I only meant to comment on the wave part of your post. Listen to jdallen  below about the Ekman pumping, as I am still learning about that myself.
« Last Edit: December 12, 2016, 12:51:42 AM by Tigertown »
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Re: The 2016/2017 freezing season
« Reply #1328 on: December 12, 2016, 12:41:25 AM »
Ekman pumping is actually less influenced by waves and more affected by longer distance movement of wind-driven surface currents causing displacement of water at depth. That movement over kilometers is what has the greatest effect - thus how water can be pulled up by the movement of ice.
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Re: The 2016/2017 freezing season
« Reply #1329 on: December 12, 2016, 01:37:36 AM »
So the ice is relatively safe from Ekman and surface wave mixing.
Or can anyone point to a ref which contradicts the above?

See http://forum.arctic-sea-ice.net/index.php/topic,1385.msg63473.html#msg63473 et seq.
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Re: The 2016/2017 freezing season
« Reply #1330 on: December 12, 2016, 02:49:17 AM »
Guys, before I came here, in fact before there was a "here" to come to, I spent a lot of time at RealClimate and I got a feel for what the climate scientists are trying to do with their assessments.

In short the statements above seem to lead us to believe that the scientists are deliberately misleading us for some reason.  After all it's blindingly obvious that it's not going to be the latter half of the 21st century before the ice goes.

But, in fact, it might just need a scientist and especially a climate scientist, to fail to see that.

Over and over again, during the debates, Gavin Schmidt has been seen to say that these annual variations must be ignored if we are to see the larger picture.  And he's right, the larger picture is 100 to 1,000 years.

So what they do is bury the annual variations in decadal averages and then bury them again in multi decadal averages.  Truth be told, if you take the 30 year running mean, we're pretty much on target.  When you look at the 2000's averaged out.  Even the 2010's, when the decade is done, will be averaged with the previous two decades to create the 30 year running mean.

The problem with this methodology, which is used by all climate scientists when they report to the IPCC, is that it fails to anticipate, or even detect, step changes when they happen.  In fact it's designed to do exactly that, remove them.

The major problem with that approach is that what is happening to the Arctic is massively driven by annual variations and those variations are getting larger as every decade goes by.  By the time that the 2010's annual variations are released from the 1990's, it will already be blindingly obvious to everyone that they are out of touch.  Also the model will mitigate to tone down even those effects.

In reality the 30 year running mean has been a wonderful ruler for measuring future change over the last 5 decades.  It' was extremely useful in the denialist rantings in the aftermath of the 97/98 nino and the return to the norm which happened there.  It forced the denialists to take out the 97/98 as a baseline and then their entire assertions fell apart.

So, I think, when railing at the "Scientists" for not predicting what we are seeing now, I respectfully submit that their models and their projections are specifically designed to ignore it.  Because, so far, by ignoring it, they have been more right than wrong.

Honestly I feel that an ice free arctic in 2022 will force them to reassess that.  Because the possible forcings created by the black swan event are enough to overwhelm the 30 year running mean and to continue with it would be foolish.  They would need to create a new baseline and then run a parallel comparison and draw conclusions that way.

Getting scientists to throw away long held and very good baselines will take an extreme act.   The same extreme act we see evolving before us in an unprecedentedly warm winter with unprecedentedly low ice volume and extent.

What I'm saying is "Don't allude motives to the Climate scientists just because they are not monitoring the same thing you are".  Because, in the end, these people have been in the firing line for a long time and the vast majority of them are both honerable and extremely thick skinned.  But, believe me, they have feelings too.
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Re: The 2016/2017 freezing season
« Reply #1331 on: December 12, 2016, 02:53:12 AM »
Accumulated Freezing Degree Days N80 thru Dec 11, 2016:

Climatology: 1653.83
2016:              853.61
Anomaly:       -800.22



Implied new ice thickness to date:
Per Lebedev:
Climo: 1.212 m
2016:  0.821 m

Per Billelo
Climo:  0.979 m
2016:   0.667 m

ktonine

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Re: The 2016/2017 freezing season
« Reply #1332 on: December 12, 2016, 02:55:25 AM »
Note regarding accumulative FDDs  The most recent 5 years are the only years to reach an accumulative FDD anomaly of -800 at some point during the freezing season. 2016 has done so two and a half months earlier than the previous quickest year (which was last year, 2015-6).  Forget the 1958-2002 baseline; even within the context of the warmest years this year is simply unbelievable. There is nothing with which to compare it.

FishOutofWater

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Re: The 2016/2017 freezing season
« Reply #1333 on: December 12, 2016, 03:15:45 AM »
Models predict the unprecedented Arctic warmth will continue for the next 2 weeks.

Ekman pumping is extremely important in the Arctic. It affects fresh water storage in the Beaufort gyre. Here's a double spaced 70 page pdf that has been cited numerous times that details the role of Ekman pumping in fresh water storage and release in the Arctic.

https://www.whoi.edu/beaufortgyre/pdfs/2008JC005104-pip.pdf

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Re: The 2016/2017 freezing season
« Reply #1334 on: December 12, 2016, 05:33:48 AM »
In short the statements above seem to lead us to believe that the scientists are deliberately misleading us for some reason.
I don't think anyone here thinks that, NeilT. It's the model extrapolation vs. state change argument playing out in real time. It's like musical chairs: it's not possible to predict in advance when the state music will stop, so some people with well-founded statistical extrapolations will inevitably be left without a place to sit. There will be schadenfreude.

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Re: The 2016/2017 freezing season
« Reply #1335 on: December 12, 2016, 07:02:29 AM »
Note regarding accumulative FDDs  The most recent 5 years are the only years to reach an accumulative FDD anomaly of -800 at some point during the freezing season. 2016 has done so two and a half months earlier than the previous quickest year (which was last year, 2015-6).  Forget the 1958-2002 baseline; even within the context of the warmest years this year is simply unbelievable. There is nothing with which to compare it.
ktonine, you wonderful chart tell THE story of this freezing season. Eventually extent will reach more or less the typical winter extent, and all will seem to be fine. But not so. And this surely will be felt strongly when summer comes along.

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Re: The 2016/2017 freezing season
« Reply #1336 on: December 12, 2016, 08:44:15 AM »
Guys, before I came here, in fact before there was a "here" to come to, I spent a lot of time at RealClimate and I got a feel for what the climate scientists are trying to do with their assessments.
<snip>
But, in fact, it might just need a scientist and especially a climate scientist, to fail to see that.

Over and over again, during the debates, Gavin Schmidt has been seen to say that these annual variations must be ignored if we are to see the larger picture.  And he's right, the larger picture is 100 to 1,000 years.
<snip>
And I think you put your finger on the pulse of it, without necessarily identifying what's happening explicitly.

Paradigm Shift.

Before I became a systems analyst and computer specialist, I studied to be a Geologist, and one of the subjects I studied in detail was the Channeled Scabland of eastern Washington and Oregon.  I think the debate around how that region was created is very germane to the debate now around climate change and the Arctic.

Back in the day (1915-1930 or so), a certain J Harlan Bretz offered up the idea that a catastrophic event (which we now know to be *multiple* catastrophic events) tore apart the Columbia basin to create the scablands.  He was fought tough and nail by the scientific establishment of the time, which had just within the previous century or so, come to understand geologic scales of time, and the idea that Natura non facit Saltum - nature does not make leaps - and the idea of any catastrophy was beyond the pale.

Bretz obviously won the debate - through the presentation of empirical evidence and the Geologic record - and we understand pretty much what happened in the NW with glacial lake Missoula.

But our current establishment is still dominated by the paradigm of incrementalism; every thing about what is happening now is utterly alien to that approach to science and change, and runs counter (Bretz not withstanding) to the best part of 175 years of scientific thinking about how the universe works.

Shaking loose of that doesn't come easily, and there are serious penalties for pushing back against it.  Dr. Wadhams for all of his more extreme views, is something of a victim of that.

Most of science, most of our experience argues against sudden change.  It's a fundamental bias, woven into how science tries to interpret events.  It *is* being pressed, VERY hard.

So here we are in the winter of 2016/2017, and events are progressing in ways that confound and astonish  most of the scientists looking at whats happening - even those who have spent an entire generation watching climate and the Arctic.  It does not fit any commonly understood theory. It does not fit with history or our experience.  Everything is more extreme, more chaotic than anything we've seen, even when we try to evaluate historical climate data going back over 2 million years. 

In short, we need to build a new paradigm, because the old one no longer works.
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Re: The 2016/2017 freezing season
« Reply #1337 on: December 12, 2016, 09:42:52 AM »
Whatever the scientific approach scientists, regardless of whoever is paying for the research, should stop talking to politicians in terms of 'mitigating' change and just tell them what we need to stop doing however politically painful it is.

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Re: The 2016/2017 freezing season
« Reply #1338 on: December 12, 2016, 12:08:26 PM »
Reading the latest post of jdallen, I was wondering what people here think of machine learning approaches. Could they help the paradigm shift?
See e.g., http://www-users.cs.umn.edu/~banerjee/talks/BanerjeeMonteleoniNIPSTutorial2014.pdf

My naive understanding (I'm neither a climate scientist nor a specialist in machine learning) is that machine learning might be less biased (less a priori reluctant to sudden change, for example) than "classical" modeling methods.

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Re: The 2016/2017 freezing season
« Reply #1339 on: December 12, 2016, 12:24:36 PM »
Whatever the scientific approach scientists, regardless of whoever is paying for the research, should stop talking to politicians in terms of 'mitigating' change and just tell them what we need to stop doing however politically painful it is.

For reference to how well that works, have a look in the RealClimate posts around the time of the Copenhagen climate summit.  To paraphrase the scientists, they told the politicians what their certainty meant, how it worked and what should be done.

The politicians looked at the figures and said, paraphrased

"Come back and tell us when you are 100% certain but you'll have to have EVIDENCE mind.  then you can tell us what we need to do!".

Can you imagine how they felt?  They had, in some cases, spent years on this, some intruding heavily into their family lives to do so.

Essentially the politicians said "When the roof falls in tell us what to do".  Of course the answer is "Put your head between your legs and kiss your ass goodbye".

Many of those scientists involved in Copenhagen refused, ever, to have anything to do with a climate summit again.
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NeilT

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Re: The 2016/2017 freezing season
« Reply #1340 on: December 12, 2016, 12:28:42 PM »
On a more thread related note, I was playing with Chartic and I noticed that all the years to 2003 ended the year on a declining trend of extent.

However from 2004 onwards every year but 2010 ended the year at almost exactly the same extent.

I'm wondering if 2016 is going to break that trend and start a new end point. I'll be looking to see.

I posted this on the blog too.  But it's an interesting view.  Almost as if something changed in 2004 which set us on the current path.

For those who have been watching this for quite a long time, 2005 was the start of the WOW LOOK AT THAT press headlines about sudden drops in the Arctic.  2005 was the first real shocker.  2006 was kind of like 2011 and much more like 2016.  We know 2007 and 2012 of course.

What I'm wondering is whether 2016 will be the start of a new baseline exit point trend or whether it's just another outlier year like 2010.

Because if it's another baseline then things are going to heat up (pun intended), rather rapidly...

One to watch.
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NeilT

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Re: The 2016/2017 freezing season
« Reply #1341 on: December 12, 2016, 12:54:17 PM »
Reading the latest post of jdallen, I was wondering what people here think of machine learning approaches. Could they help the paradigm shift?

This comes into my field too.  I had a very rapid scan of the presentation looking for key words and processes.  I moved from programming, analysis, architecture and onto project management but have taken my technical knowledge of computing with me on the journey.

In short a computer processor adds two numbers together.  Very quickly to be sure but that's what it does.  Everything else a computer dues comes down to programmers and how they create their program environments to do things.

In short computers are just fast number crunchers and the logic is created by humans.  Reading that presentation I didn't see anything about AI or neural networks, although I scanned it pretty fast so could have missed it.

Without either of those two, which are still in their infancy, all you get is a bunch of programs, written by the same people who already produce the algorithms, to do the same job faster.

I would expect that ML would only "learn" the same things we are learning, just faster and with more evidence.

In order for ML to take us beyond what is in the current science, the ML system would need to be able to create new algorithms to explain these data.  I saw nothing about that, it was all human based.

In the world of computing, we have a term.  GIGO.  Garbage In Garbage Out.  We have noisy and incomplete data sets.  We have conflicting data sets and we have conflicting interpretations of those data sets.  When the quality of your output is directly proportional to the quality of your input, I would expect a machine to make a worse job of it than a human.  Because we do learn and can make intuitive leaps.  Computers cannot make intuitive leaps.  Yet.  First you have to enable a computer to think and reason.  That is AI which is why I was looking for it.

So, in short, I would expect ML to make things faster and easier.  But only produce the same results because it's using the same base data and the same algorithms.  In fact a computer could come to all sorts of crazy hypotheses which a human would automatically reject as being "out of bounds"

Sorry for the diatribe but that's how I see it.
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jai mitchell

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Re: The 2016/2017 freezing season
« Reply #1342 on: December 12, 2016, 01:04:50 PM »
back on topic please, you can have all kinds of great conversations about other things in other forums. this is the re-freeze thread. so talk about freezing or arctic conditions only please.
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Re: The 2016/2017 freezing season
« Reply #1343 on: December 12, 2016, 03:02:04 PM »

In short a computer processor adds two numbers together.  Very quickly to be sure but that's what it does.  Everything else a computer dues comes down to programmers and how they create their program environments to do things.

Neil, in my non expert opinion, that analysis is not correct when applied to machine learning.When it comes to machine learning how the calculations are performed does not matter at all. What counts is the input and output. That's why  Alpha Go can defeat master Go players, even when Go has many more possible outcomes than computers could ever compute. Not even the programmers know how Alpha Go beat their opponents. Alpha Go simply looked at 30 million games and figured out the best algorithm for the task.  The algorithm it used is useless for any other application and unintelligible to humans. Yet it works.


Quote
In order for ML to take us beyond what is in the current science, the ML system would need to be able to create new algorithms to explain these data.  I saw nothing about that, it was all human based.


I think Machine learning will help but it will be a black box. We give it some input, it calculates the best algorithm for the output, and it gives us the answer. The algorithm the AI used would be useless to anyone but a computer.


Quote
In the world of computing, we have a term.  GIGO.  Garbage In Garbage Out.  We have noisy and incomplete data sets.  We have conflicting data sets and we have conflicting interpretations of those data sets.  When the quality of your output is directly proportional to the quality of your input, I would expect a machine to make a worse job of it than a human.

Because we do learn and can make intuitive leaps.  Computers cannot make intuitive leaps.  Yet.  First you have to enable a computer to think and reason.  That is AI which is why I was looking for it.

Although GIGO is vital for most human endeavors, machine learning excels at using that very garbage to produce the best possible results.  When training  for its championship games, alpha GO looked at 30 million games, many of which  would be considered noise by any expert training for Go. It still used them to win.

Computers will never think like humans unless they are born, fed by their caretakers, learn to walk, scrape their knees, become  teenagers with all its life forming experiences, fall in love, get rejected etc. etc. To think like humans the AI must have a human experience. We can make an AI pass a Turing test without the AI ever thinking like an actual human. Is the opposite of isolating a  human for all his  life. Such person if taken out wouldn't pass a Turing test.

As it is ML can already help  with climate change. It already is if you count google's AI increasing the efficiency of google's massive data centers, or AI's improving battery densities for Tesla.

 Neil, if you want to talk about this further perhaps start a new thread in solutions? This is indeed a fascinating topic.

This is terribly off topic, so this is my attempt to somewhat bring it back to topic, the freezing  season.

With the alpha Go analogy, if we had 30 million earths, each following the the same physics but with different initial values and forcings, then we could feed it to a Machine Learning algorithm that could probably tells us the final outcome of this freezing season and of the arctic itself.

But we only have one Arctic. The data really doesn't really goes back in time many years, and the changes experienced since 2007. Alpha Go's approach is not directly applicable to the Arctic. But there may be other approaches that can help.



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epiphyte

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Re: The 2016/2017 freezing season
« Reply #1344 on: December 12, 2016, 03:17:16 PM »
Reading the latest post of jdallen, I was wondering what people here think of machine learning approaches. Could they help the paradigm shift?
See e.g., http://www-users.cs.umn.edu/~banerjee/talks/BanerjeeMonteleoniNIPSTutorial2014.pdf

My naive understanding (I'm neither a climate scientist nor a specialist in machine learning) is that machine learning might be less biased (less a priori reluctant to sudden change, for example) than "classical" modeling methods.

Machine learning, thus far at least, is mostly predicated on exposing things that are already there; finding needles in haystacks and testing possibilities against sets of known circumstances. Most likely the current state of the art in this field is less well suited to anticipating sweeping change than we are.
Also ML has something of a credibility problem when it comes to doing science, because ML techniques are often inscrutable; e.g. they employ 'hidden' models which are trained to arrive at the statistically correct answer most of the time, but cannot easily explain any given result in terms of a logical chain of reasoning.

...so not much help to be had on that front, I fear.

Ooops... mandatory on-topic addendum coming up... Its very cold here in the upper midwest right now - I guess there just isn't enough polar vortex to go around these days...

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Re: The 2016/2017 freezing season
« Reply #1345 on: December 12, 2016, 03:25:48 PM »
The rub on machine learning for 16/17 freezing is that unless someone made it a big project I don't see it being that useful, perhaps only as good as forecasting ice disposition a few days into the future. With how unprecedented the past few weeks have been, I'd also be wary of a model that relied too much on historic data since it would have a hard time accounting for what we are seeing now.

Its a shame the NIPS slides didn't cover any deep learning, its also a shame that NIPS'16 just ended and I can't find anything about climate modeling in the presentations. Archimid, don't give AlphaGo too much credit, the paper google released on it is a bit technical but the entire system is pretty straightforward to understand. As with all things deep learning, the end result will depend on the quality and quantity of data available.
« Last Edit: December 12, 2016, 04:58:43 PM by dosibl »

A-Team

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Re: The 2016/2017 freezing season
« Reply #1346 on: December 12, 2016, 03:53:44 PM »
Quote
stay on-topic
If only we had a forum called Best Forum Posts (which under no foreseeable circumstances would include more than 4-5 per 1000, two weeks at current rates). Here #1330 and #1336 might very well make the cut.

The Chukchi is about the same this morning -- a 896 km swim due north from Big Diomede to the first ice solid enough for a walrus, seal or polar bear to haul out on for a rest.

The GFS forecast had extremely cold Siberian air passing north of Wrangel but on the subject of warm surface air being entrained over the Bering/Chukchi, seems to be in conflict with ECMWF. That would be unremarkable except that ECMWF is more skilled whereas forecast products like nullschool and possibly Hycom use GFS. [fixed by JimH in #1347: uses NavGem; nullschool ECMWF available at windytv]

Consequently I've issued a standing W&S emergency advisory hindcast (wait-and-see what happened yesterday). In terms of re-analysis, the lee side polynya around Wrangel island is quite informative. While that is not exactly open water, it shows when there was enough oomph in the mean wind field to move the needle. Similarly for small islands of Franz Josef and Severnaya Zemlya.

The top animations run from 01 Nov to 11 Dec. The Modis image and context are from the 7th; the best fit to our favorite ice products seems to be 'none of the above'. Nice bit on ice types and formation here: http://www.pmel.noaa.gov/arctic-zone/essay_wadhams.html

Below is a sketchy scenario for this chain of events hypothesized as the 'new normal' weather pattern (not freak weather), feel free to revise, toss, or enhance:

-1- Emissions cause greenhouse effect, raising air and water temperatures.
-2- Arctic is most affected in autumn via amplification mechanism.
-3- The heat gradient between equator and Arctic is diminished.
-4- Jet stream slows and wobbles according to franciscan theory.
-5- Polar air streams down to mid-latitudes in eastern US on down-wobble.
-6- Mid-Pacific and Siberian air stream north on up-wobble to replace missing Arctic air.
-7- Warm air and water flow north through Bering Strait to the Chukchi, stalling lateral refreeze.
-8- Return to -4- and repeat as appropriate.
-9- Expect two strong winter storms like the 27 Dec 15 to bring moisture and insulating clouds.
-10- Less winter freeze onto bottom ice results in thinner ice at beginning of melt season.
-11- The open water season better matches peak insolation season.
-12- More water vapor in air means more energetic summer cyclones early and late.
-13- Reduced albedo in summer and thin ice/dry snow cover in winter add to planetary heat.
-14- Return to -1- and repeat until permafrost and methane kick in.
« Last Edit: December 12, 2016, 07:46:58 PM by A-Team »

bairgon

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Re: The 2016/2017 freezing season
« Reply #1347 on: December 12, 2016, 03:55:04 PM »
On-topic post.

I was looking at the Nares Strait satellite pictures and posted about a polynya opening up in the Lincoln Sea at the mouth of the strait (see http://forum.arctic-sea-ice.net/index.php/topic,176.msg96314.html#msg96314)

This can be seen in the recent Lincoln photos at http://ocean.dmi.dk/arctic/lincoln.uk.php and in particular http://ocean.dmi.dk/arctic/images/MODIS/Lincoln/20161211s01a.ASAR.jpg. The polynya is about 100km x 100km and ice continues to break off and flow down the Nares.

Looking back through the Sentinel images shows this polynya starting to open on 7th December.

I've found a reference here which describes this polynya as a standard feature. This references a paper by Kozo, 1991 (preview here), describing this polynya with a solid arch from Greenland to Ellesmere island, with an opening forming at the top of Nares. He says that the sea ice transport normally stops by January, so this pattern appears to be fairly normal - at the moment.
« Last Edit: December 12, 2016, 04:32:36 PM by bairgon »

Jim Hunt

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Re: The 2016/2017 freezing season
« Reply #1348 on: December 12, 2016, 04:13:30 PM »
That would be unremarkable except that ECMWF is more skilled whereas forecast products like nullschool and possibly Hycom use GFS.

The nullschool clone at Windyty/Windytv supports ECMWF and GFS:

https://www.windytv.com/

Hycom uses NAVGEM forcing

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Re: The 2016/2017 freezing season
« Reply #1349 on: December 12, 2016, 04:49:38 PM »
Apologies for triggering the off-topic forking. Discussion on Machine Learning re-started at
https://forum.arctic-sea-ice.net/index.php/topic,1811.0.html