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Messages - Sterks

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1
I think I'm going to earn a position of target of some criticism and unfriendliness, but I've got the impression that some of you people are selectively ignoring facts:
- It is true that the Pacific sector has a very bad color. Nevertheless, the Beaufort Sea (key in the destruction of ice) has only come to a modest start. More importantly, the Beaufort Sea has ended a lot colder than last spring. See how fractures are frozen as soon as they are opened and we are on May 11th. The refreezing came very late (December) with the loss of ocean heat that this entails. Not only that, the snow has generally been scarce in the area, so ice has nicely thickened reaching up to three meters (see Piomas, Cryosat).
- We are waiting for a heat wave that some members are announcing since April. Be not disappointed, if it does not come. I put the chances at 50% that heat will be maintained during the month of June, that's the key. Why? Because the deposited snow on the continents, not only in Asia but also in America, broke all sorts of records, perhaps caused by the extreme deviation of the Arctic Autumn and the Winter. Could this not cause a cooling effect in the summer weather? Seems a bouncing oscillating effect that is not nuts at all.
- The extent is in normal values ​​of the 21st century, far from the lowest data from other years. Do not forget one thing: the extent and the area are very important to give a boost to the melting season or to inhibit it, and the critical time now begins. The albedo potential maps just show that the anomalies in the Pacific (relatively unimportant) are canceled out by the anomalies in the Atlantic (relatively unimportant), with anomalies in the Arctic proper that are just irrelevant for the time being. The brief time of change must come.
- Volume also rebounds

It's still early to forecast (also on volume), I'll wait as much as possible to make a prediction for this poll, to have a clearer judgment. A very strong heatwave must come, when it comes, if it comes, or if it doesn't, I will put my vote or just comment about it if the voting is closed.
I wanted to quote the previous comment to add the context of what has happened since then with snow cover. I add a gif with May snow cover anomaly so far, from the Rutgers University Snow Lab
It is undeniable this year spring is late in many locations of the Northern Hemisphere, just as much early it was in preceding years. The wave of heat is coming north but with a delay caused by the buffer of heavy snow fallen in the winter.
This has a cooling effect, and as a consequence this will substract some of the heat reaching the Arctic via continental air acvections in the coming weeks.
However this is only a factor. Still not made up my mind. And it is true the heat at least is advancing much faster from the American side, this is truly dangerous.

2
Arctic sea ice / Re: The 2017 melting season
« on: May 11, 2017, 06:04:03 PM »
Meanwhile, jaxa May 10 extent up by 15,000 km2. That is 10 days and very nearly 700,000 km2 behind 2016, and 5th lowest in the satellite record. And yesterday AMSR2 volume ticked up a bit. That is a lot to make up in the remainder of the melting season.

On the other hand, the latest from robertscribbler.com confidently predicts significant arctic warming events in the next few days, and ASIF is full up images of the mess the ice cap is in.

But as of today as far as extent is concerned 2017 is a very ordinary year.

i mentioned it already and gladly repeat: if the ice were compact as it was before 2015 it would take much less space (extent)

like others i strongly believe, even though extent has and impact on many feedbacks like albedo and temp exchange etc, it will more and more be a poor instrument to measure the amount and state of the ice. i'd go that far to say that any mention of extent to describe what's happening is useless to such a high degree that it's not worth to mention, an inefficient instrument that is causing more and more fruitless discussions and is drawing more and more a false (mislieading) picture of events.

it's just leading nowhere, the extent is 5th lowest and the state and amount (volume) of the ice is 1st lowest/1st shittiest ever.

any information that will draw a picture that is contradictory to the reality of what's going on is misleading IMO
If I want to buy a house, the first I think is "how many square meters". It does not say much, but automatically helps me to discard 70% of the too small or too big houses.
It is very useful. It is very informative. Does it give me the full picture of the house? By no means.
Good. The extent of Arctic ice is much more useful, more informative about Arctic ice. AND IT'S VERY RELEVANT on its evolution, NOT SHITTY, because you will observe solar radiation and that this solar radiation is absorbed and not reflected back to space. Larger extent, now that there is no surface melting, simply means that less solar radiation is being absorbed by our planet Earth, and I welcome that it is larger than same date 2016.

a) i mentioned that with albedo and stuff in the same context in another thread, hence agree to that but cannot write the same excerpt each time in full in various threads

b) we're not entirely talking the same thing, i was only referring as to measuring the amount and the state of the ice while there is more to it, you're right

c) reason why a posted at all is that too many read too much from extent data IMO too much fuss about daily ups and downs while the above remains true

in short, the word shitty is inappropriate, lost my horses for a sec, while the key point i wanted to make, perhaps not perfectly put, remains. you'll see that withing the next 2-5 years extent will loose it's rank as the main indicator of sea-ice development to volume and what i said will become common sense, at least roughly.

thanks for replying, even thoug, as yo can see in my other post, i was aware, it's worth to mention because i neglect on that in this thread.
Magnamentis:
Sea ice extent is pretty close to what in physics is called an "observable", that is, a dynamic variable that can be measured. It is NOT an observable, but the required algorithms and modeling to derive the variable from the observables (microwave signals, satellite relative position and velocity which are not observables but the satellite positioning determination system takes care of that; calibration of instruments;  and more) are immediate and straightforward, almost like linear rules, except for the controversial thresholds. However, thickness is so much farther from being an observable. I agree. The rank of extent will diminish, but I would assume this will happen in more than five years.

3
Arctic sea ice / Re: The 2017 melting season
« on: May 11, 2017, 02:26:22 PM »
Meanwhile, jaxa May 10 extent up by 15,000 km2. That is 10 days and very nearly 700,000 km2 behind 2016, and 5th lowest in the satellite record. And yesterday AMSR2 volume ticked up a bit. That is a lot to make up in the remainder of the melting season.

On the other hand, the latest from robertscribbler.com confidently predicts significant arctic warming events in the next few days, and ASIF is full up images of the mess the ice cap is in.

But as of today as far as extent is concerned 2017 is a very ordinary year.

i mentioned it already and gladly repeat: if the ice were compact as it was before 2015 it would take much less space (extent)

like others i strongly believe, even though extent has and impact on many feedbacks like albedo and temp exchange etc, it will more and more be a poor instrument to measure the amount and state of the ice. i'd go that far to say that any mention of extent to describe what's happening is useless to such a high degree that it's not worth to mention, an inefficient instrument that is causing more and more fruitless discussions and is drawing more and more a false (mislieading) picture of events.

it's just leading nowhere, the extent is 5th lowest and the state and amount (volume) of the ice is 1st lowest/1st shittiest ever.

any information that will draw a picture that is contradictory to the reality of what's going on is misleading IMO
If I want to buy a house, the first I think is "how many square meters". It does not say much, but automatically helps me to discard 70% of the too small or too big houses.
It is very useful. It is very informative. Does it give me the full picture of the house? By no means.
Good. The extent of Arctic ice is much more useful, more informative about Arctic ice. AND IT'S VERY RELEVANT on its evolution, NOT SHITTY, because you will observe solar radiation and that this solar radiation is absorbed and not reflected back to space. Larger extent, now that there is no surface melting, simply means that less solar radiation is being absorbed by our planet Earth, and I welcome that it is larger than same date 2016.

4
I think I'm going to earn a position of target of some criticism and unfriendliness, but I've got the impression that some of you people are selectively ignoring facts:
- It is true that the Pacific sector has a very bad color. Nevertheless, the Beaufort Sea (key in the destruction of ice) has only come to a modest start. More importantly, the Beaufort Sea has ended a lot colder than last spring. See how fractures are frozen as soon as they are opened and we are on May 11th. The refreezing came very late (December) with the loss of ocean heat that this entails. Not only that, the snow has generally been scarce in the area, so ice has nicely thickened reaching up to three meters (see Piomas, Cryosat).
- We are waiting for a heat wave that some members are announcing since April. Be not disappointed, if it does not come. I put the chances at 50% that heat will be maintained during the month of June, that's the key. Why? Because the deposited snow on the continents, not only in Asia but also in America, broke all sorts of records, perhaps caused by the extreme deviation of the Arctic Autumn and the Winter. Could this not cause a cooling effect in the summer weather? Seems a bouncing oscillating effect that is not nuts at all.
- The extent is in normal values ​​of the 21st century, far from the lowest data from other years. Do not forget one thing: the extent and the area are very important to give a boost to the melting season or to inhibit it, and the critical time now begins. The albedo potential maps just show that the anomalies in the Pacific (relatively unimportant) are canceled out by the anomalies in the Atlantic (relatively unimportant), with anomalies in the Arctic proper that are just irrelevant for the time being. The brief time of change must come.
- Volume also rebounds

It's still early to forecast (also on volume), I'll wait as much as possible to make a prediction for this poll, to have a clearer judgment. A very strong heatwave must come, when it comes, if it comes, or if it doesn't, I will put my vote or just comment about it if the voting is closed.

5

May I speculate that you just recently learned about the bathymetry of the Arctic Ocean and implications on oceanic inflows and outflows... and you changed your mind about blue ocean events just as recently? See below (sorry for doing this but couldn't help after you mentioning again the curve I plotted above, that does NOT represent any minimum extent in particular:-/ ).

Edit. By the way I discussed about this last year mentioning an Arctic Sea Ice News article

https://forum.arctic-sea-ice.net/index.php/topic,382.msg84116.html#msg84116

You may want to read the article, as it is out of the question bathymetry has a large influence.... (but inconclusive, as I am because it is a very complicated matter... maybe we will learn something this year).

Edit edit. And even more interesting this response by Bill Fothergill
https://forum.arctic-sea-ice.net/index.php/topic,382.msg84153.html#msg84153

And this by Rob Dekker
https://forum.arctic-sea-ice.net/index.php/topic,382.msg84140.html#msg84140

seaicesailor:

1. Yes, I wrote that about this season, but I was already convinced that there is not enough energy from insolation alone to melt out all Central Arctic areas where the weather is cold, the pack is closed until August and the warm currents, whether from the Atlantic Ocean or from the Pacific Ocean, do not reach such high latitudes. In any case, when I wrote that I was also thinking on Fram Export event as occurred in 2007. During that summer, export was non-stop, in opposition to what usually happens in most summers. If this summer is warm and also the export continues, we may see a new record far exceeding the previous one. Happy?
2. The article you mention does not but confirm my positions as well as Bill Fothergill's comments and (in part) Rob Dekker.
3. The Canada Basin is a more special place. For example, thanks to the Beaufort Gyre that rotates on top of it, upwelling currents happen along the coast of Canada and Alaska and the Chukchi Sea. The upward flows can transport Atlantic water from the abyss through the layers of Atlantic and Pacific halocline and mix it up with the mixed layer. The article RoxTheGeologist links to mentions it. There are also many eddies created by instabilities of currents that always appear at the slopes of the continental shelf. Also mentioned in the article. This makes the Beaufort Sea a very dynamic sea in summer, where melting can continue at high pace, in which differences in salt content and temperature can arise from the most unexpected places. The melting is also supported by frequent warm air intrusions from the continent, and the albedo feedback mechanism. However, the Beaufort Sea ice used to survive the summer in the 20th Century. Is it not surprising that on top of the whole Canada Basin that ice was able to survive? Global warming means that the Multi Year Ice no longer survives in the Beaufort Sea.
4. In any case, I reaffirm my position. Not that this denies anything. I simply think the AGW progresses slowly and, as the Canada Basin is now free of ice when it was not the case 20 years ago, the same will happen with the other basins. But I'm not sure if I will get to see it, unless perfect conditions happen as what I implied in January and in paragraph 1 of this comment.
Apologies for the lengthy answer

6
I thought ocean currents were not merely surface water phenomena. Indeed, that the volume of water moving in these currents made the mightiest land-based rivers appear as tiddly streams. A metre or two of surface ice not much of an obstacle, so bottom melting can continue until the heat is exhausted?

And I am sure that ASIF has the people who have the data on the warm and cold currents flowing in the Arctic together with the staggering amounts of heat and cold transported within them. Only with that and assessments of the quantity of heat absorbed by insolation into the ocean can reasoned conclusions be drawn?
Alright. There are many sorts of currents. Yes currents are complicated but there is an unavoidable tendency of warmer saltier water to sink in the presence of colder fresher water, and that happens at the big slopes of the Basins of the Arctic Ocean. That this colder fresher water exists on top of it all is one interesting thing, which seems to me is not going to change in one season, and therefore I don't believe in any blue ocean event anytime soon. What seaicesailor has depicted in red looks to me as a very reasonable boundary of a very bad season nowadays. Warm currents cannot melt ice over the main Arctic Basins (the Canada Basin is a special case that we can discuss at length).



7

Not so sure about how much the bathymetry plays a role, everything has a limit.

This plot an envelope-curve, a minimum of minima of September NSIDC extents. I have taken the ice edge for every year minimum and kept only the edge of each year that is closest to the Pole. I only needed from 2016 back to 2007. Before that year, all the ice edge at September fall out of the curve below.


Indeed! You are supporting me in my claim that the bathymetry is likely to prevent the so-called blue ocean event for many years. That red line you have drawn so clearly follows the bathymetry of the Atlantic side. Not so much the Pacific side but taking into account ocean stratification on that side is very special, with a third layer of Pacific water which offers cooler fresher water than the Atlantic, helping the ice to survive, but also salty and warm enough, so much that it will support the albedo feedback during the summer in the seas of Beaufort, Chukchi and ES.

Indeed, I like your plot, that represents the ice edge as I imagine it at the minimum of this year or a bad year, give or take 500,000 km2. I repeat, only a strong "flushing" event during summer as it has never happened in summer except for 2007 and 2010-2012 -but stronger- or very strong storms could end with that core of ice that you show in your map. And notice that the region you are marking is approximately the same as the region of MYI as marked in the last ice-age maps, and the thickest in Cryosat 2 and PIOMAS. Likely to survive!



8
Arctic sea ice / Re: The 2017 melting season
« on: May 09, 2017, 09:57:19 AM »
I think I am going to move this to a separate thread, but it is interesting to consider how much extra energy is required to bottom-melt MYI in the Arctic Ocean because it has strong implications in this melting season:
- Out of spring, water right underneath the ice is at -1.8C in thermodynamic equilibrium  with the freezing bottom.
- Let's say bottom melting starts in June/July depending on the location (year/round near Atlantic currents).
- For MYI, after a while of bottom-melting the half a meter or so of last season bottom-freezing, the temperature of the water has to raise from -1.8C to 0C in order to continue melting. In contrast, for the more saline FYI, melting proceeds at or slightly above -1.8C.
- This raise of temperature to continue bottom-melting MYI must happen for the whole water column of the mixed layer. In other words, the mixing that happens in this layer will take care of keeping its temperature homogeneous, with a turnover time of the order of the day or a few days.
- Assume the mixing layer is 20 to 40 m depending on location. Let's take 30 m in average.
- The energy for raising 1.8 degrees 30 m of water is equivalent to that needed for bottom-melting approximately 0.75 m of ice!!!! (since raising 1C of a 80m-deep extent of water requires the same energy to melt 1m of the same extent of ice)

So what happens this summer? In parts of the pacific half of the Arctic, and, especially, along Eurasia, we find typically 25-100 cm thinner ice than any previous year.

https://forum.arctic-sea-ice.net/index.php/topic,119.msg112166.html#msg112166

 On top of that, most of it is FYI, which will require "75 cm-equivalent less energy" to start bottom-melting than MYI. The MYI is mostly accumulated in a region that is gradually melting out no matter what due to its proximity with Atlantic water.

So as in 2013 (or even more than 2013), we will have to ask ourselves, in case it is an uneventful season, why there was no record or even <1m km2 ice in September. Something must happen in the melting season to prevent so (negative feedback due to snow cover, a cold PAC to prevent insolation and WAAs,...). Otherwise I have little doubt we can get a record low in September.

Good exercise. However, we must not forget that there are ocean currents in the Arctic that help spread that energy. And those streams end abruptly in certain areas of the Central Arctic as a result of the oceanographic topography. In other words, the ice can melt a lot from this distribution of energy, but upon reaching a certain high latitude, the flow is off. Coincidentally, the albedo feedback too. Note that we are talking about the central Arctic, which will be frozen and cold until August.

Only two mechanisms I can imagine. One is powerful export of ice toward the Atlantic Ocean during the summer, but does not seem likely at all, and very heavy storms in August as well as last summer.

If Neven thinks so yes, we can move this discussion elsewhere.

9
Bathymetry, bathymetry, bathymetry, BATHYMETRY!!!
Inconvenient truth to ignore?

The floor is the limit (except from November 2012 Arctic Sea Ice News)

Research by our colleagues Jamie Morison at the University of Washington Seattle and NASA scientist Son Nghiem suggests that bathymetry (sea floor topography) plays an important role in Arctic sea ice formation and extent by controlling the distribution and mixing of warm and cold waters. At its seasonal minimum extent, the ice edge mainly corresponds to the deep-water/shallow-water boundary (approximately 500-meter depth), suggesting that the ocean floor exerts a dominant control on the ice edge position. However, in some cases, ice survives in the shallower continental shelf regions due to water circulation patterns. For example, the shelf area of the East Greenland Sea is almost always covered with sea ice because the southward-flowing cold Arctic surface water helps to limit melt.

In contrast, ice disappears in shallow areas like the Barents and Chukchi seas that are subject to warm ocean waters and river runoff. River runoff and ice melting have also contributed to changes in the amount and distribution of fresh water in the Arctic.


http://nsidc.org/arcticseaicenews/2012/11/arctic-rapidly-gaining-winter-ice/

10
Nobody wants to talk or mention, or even think about the bathymetry of the Arctic Ocean? In my eyes, I'd say it is the number one factor influencing the minimum ice extent shape in September.
How much extra heat makes for keeping same excess heat on the surface, if it badly tends to sink and sink? It's a very physical discussion.
Voted 2060-2070.

11
Arctic sea ice / Re: The 2017 melting season
« on: April 07, 2017, 02:46:34 PM »
Somebody mentioned here that March 2017 month had been the warmest on record for the Arctic, but I can't find the reference.
Nonetheless, below a quote from the global temperatures thread with a map that illustrates that fact, and the NOAA forecast for April 2017.

Guys, Copernicus just arrived with their analysis for March. No surprise here, March was the  second warmest on record and 0,10oC cooler compared to March 2016. This number make me believe that a NASA GISS anomaly around 1,07-1,15oC above the average seemsquite reasonable.




12

I'll pass on the "hidden behind your desk" and other nonsense in your post, just as I ignored most of ktonine's/Kevin O'Neill posts that just misrepresent what I wrote.

Ok, it was not fair from me to write that (behind my own desk), I am sorry.


If you are interested in the Notz & Stroeve paper but can't be bothered with reading it, there is a short YouTube video (< 5 minutes) with Dr. Notz presenting essentially the same ideas during the COP21, with various charts, etc.
Here: https://www.youtube.com/watch?v=kHXg6ucTM1o

The example of scientific paper that contradicts Ding et al that you bring about is not that good. I think they directly assume no internal variability. How's that for a model? They could have used something fancier. In fact, they could have used some model.
But no, it is sort of a direct ad-hoc linear correlation C02 -> ice loss only meant to work for the NH with kind of a moral intention (you burn this? then you are responsible of the loss of that amount of ice). And as a side, projecting their correlation into the future we can keep our party and our burning rates until 2040 or 2050, that the Arctic will keep some ice in September, then we stop, and fix it. It is just linear, isn't it?

Bad example really.

13
Andrew, now that you insist, to insinuate of having preposterous claims and using tools that justify priori conclusions sound like some of the worst insults you can throw to a scientist or to anyone doing or pretending to do an investigative work with rigor.
I mean, isn't it obvious?
But yeah, don't apologize, you're behind, hidden in your desk, safe, Eric S. has shown really ugly arrogance too.
Dr. Ding and Rob Dekker keeping the level so high in contrast. Chapeau

14
Arctic sea ice / Re: The 2017 melting season
« on: March 06, 2017, 05:09:25 PM »
This image pertains to the melting season thread. Day 64 2017 snow cover anomaly.
Regardless of the massive snowing this winter, there is an early beginning of spring in many locations of the northern hemisphere as last year. Less snow means more insolation in areas where it already does matters. It's still early but everything counts. An equivalent of FDD might be devised for land.

15
Arctic sea ice / Re: The 2016/2017 freezing season
« on: March 06, 2017, 04:14:06 PM »
The already announced push of trans-polar drift, usual in these dates as far as I know, is confirmed and will last for five days according to the ECWMF. Within the realm of possibilities not much more, but this could be the closing event of this eventful freezing season.

16
Arctic sea ice / Re: The 2016/2017 freezing season
« on: March 03, 2017, 09:58:46 AM »
other negative feedbacks of storminess could be later refreezing, greater accumulations of snow in winter and spring, and overcast skies in May and June.
Out of curiosity why stormier Arctic in Fall/Winter is related, or comes hand in hand with a stormier Arctic in Spring/Summer?
Speculation based exclusively on the observations of the past three years, admittedly.

17
Arctic sea ice / Re: The 2016/2017 freezing season
« on: March 02, 2017, 10:37:18 AM »
Thought people might find this interesting... Beaufort yesterday vs. this time last year (i.e. mid-crackopalypse)...
Last year, there was actually something to *crack*, and other bits of it which were solid enough to resist.

Everything there is FYI, and most of it less than 1.7M; if it gets stressed, it breaks, and spreads out the force, rather than transmit it.
In my humble opinion, there has not been appreciable ice moving compared to the same date last year. If it stays quiet until June, will be healthy. That's a big IF anyway.
This is consistent with the observation that a predominantly low-dominated Arctic weakens the Gyre. Weakening of the Gyre stop positioning MYI in the Beaufort Sea and creates no ocean gaps far so easy. This might be considered as being a negative feedback due to a wetter and stormier Arctic (positive for ice rebound); other negative feedbacks of storminess could be later refreezing, greater accumulations of snow in winter and spring, and overcast skies in May and June.

18
Arctic sea ice / Re: The 2016/2017 freezing season
« on: February 20, 2017, 03:43:47 PM »
Might that high cause a cracking event (albeit not as big as the one in 2013)?
It will be interesting to evolve toward the summer with similar FYI (although thinner) in the Pacific half of the Arctic as 2013 but a different weather.
To start with the departure, early opening along the Alaskan coasts in Feb-April like last year rather than cracks in the middle of the pack. I guess the strong high forecasted can cause either. But the ice is still really thin in some areas of Beaufort sea particularly close to Barrow point
Coincidentally, the high pressure system will produce significative winds in reaching the NorthWest corner of Alaska. These are day three to six of the latest ECMWF:

19
Arctic sea ice / Re: The 2016/2017 freezing season
« on: January 27, 2017, 12:44:00 PM »
5-day averaged MSL pressure ECMWF, next 5 days. Tendency to build up pressures in the Pacific half.
The Transpolar drift is beating records this year.

20
Arctic sea ice / Re: The 2016/2017 freezing season
« on: January 23, 2017, 04:56:16 PM »
[.....]
Yes, it is thin, and yes, it will melt in summer. However, this storm increases the amount of buffering in summer for the sea ice as the 40cm ice that will exist at the end of this freezing season in the Bering Sea will take time and energy to melt. All ice takes time and energy to melt, even thin ice. Yes, it is (likely) thinner than previous years in the Bering. No, it will not vanish instantly when the sun begins shining. The sun shines every year, year-round in the Hudson Bay and it builds ice of a meter thick or more every year. You must look at local conditions to see if it will expand or shrink.
Yes, these are very good points. I stand by my vote that this year the maximum extent will surpass those of the years 2015 and 2016.
However what strikes me is the maps of ice in the Pacific Ocean in 2012 in winter and spring. The worst summer of the Arctic ice was preceded by a very cold winter in the Bering sea.
Correlation is not probable. Other factors will play in.

21
Arctic sea ice / Re: IJIS
« on: January 20, 2017, 12:11:15 PM »
I see discussions about waves and dispersion.. anybody looking at the temperatures by the way? It's extremely cold in the Beaufort and Bering and it will be extremely cold over the CAB in the next few days. I expect piomas will be veeyextremely interesting in the next release. Sometimes things are much easier than we want to believe. When it's cold ice is formed, and viceversa... ;)

That's true, and storms bring both a warm front and a cold front associated, see snow maps recently placed in the freezing season thread. Ocean temperatures have to be affected by very low temperatures sustained for many days.
The falling snow and the cold will promote the formation of ice
But we must ask ourselves what kind of ice and what kind of integrity it has

At this rate we may see ice rise slowly and then fall dramatically as all thin ice succumbs to those waves and sunup starts.

Scary times

Above 70N, the Sun radiation is not relevant until April because, for solid parcels, albedo is very high and sunlight near horizontal, and for liquid parcels, while the air temperatures are very low, any open water element will be near -2 degC and convect and emit much more than what you get from the Sun. I think the discussion was previously resolved in this forum.
Let's not mention the Sun until April (except maybe the related to Baltic Sea and the American lakes)

22
Arctic sea ice / Re: The 2016/2017 freezing season
« on: January 16, 2017, 02:59:59 PM »
The storm has appeared in the Canada Weather Information service chart at 00Z today for the first time. Six hours later the lowest pressure level of this storm was 961 hPa
It would be interesting to understand the cyclogenesis of this particular storm. The NE corner of Greenland is a very special location, isobars take the most peculiar shapes there at many other times.

23
Arctic sea ice / Re: What are you expecting to see this melt Season?
« on: January 11, 2017, 04:52:06 PM »
[...]
If we do happen to see a 2007 type summer, I could see us losing all we have there in one go. Why? I do think that the thick ice that is currently there is nothing more then contaminated salty ice that under 2007 or 2012 type summer will vanish in a flash because there is no solid structure to that ice.
Without knowing the whole story of 2007, only partial bits, a scenario like you describe seems entirely reasonable as leading to the first summer virtually without ice. This is my expectation if such weather comes

24
Arctic sea ice / Re: 2017 IJIS extent maximum prediction
« on: January 09, 2017, 09:45:59 AM »
I argued in another thread that Global and Northern Hemisphere temperatures have abated somewhat after two years of Niño or near-Niño. They are still running high but not as much as one year ago.
.https://forum.arctic-sea-ice.net/index.php/topic,445.msg97788.html#msg97788
Therefore, we may expect a maximum ice extent that is low, but perhaps not as low as 2015 & 2016. A comeback to 14 - 14.25 million km2 perhaps. The maximum ASI follows AGW trends whereas the minimum is more sensitive to other factors.

25
Arctic sea ice / Re: IJIS
« on: January 05, 2017, 01:13:19 PM »
I wonder if we exceed previous recent maximums, for reasons that actually make melt season even more ominous... consider that both Baffin and Okhotsk are now running very strong + ice anomalies; all this will melt out in winter anyways. Both Baffin and Okhotsk have significantly more room to increase their extent as well, vs. Chukchi and Kara which are substantially more constrained by both geography and oceanic heat.
It should be noted that, although Global and Northern Hemisphere temperatures are still running high, the anomaly has taken more moderate values in December than in past year 2016 and great part of 2015. It seems the direct effects of the last Niño have faded somewhat.
https://forum.arctic-sea-ice.net/index.php/topic,445.msg97788.html#msg97788
Therefore, we may expect a maximum ice extent that is low, but perhaps not as low as 2015 & 2016
As for the fate of the Beaufort sea and Chukchi sea ice, it all depends on how warm the summer will come. This ice is ready for a very bad carnage but you will need the sun

26
Arctic sea ice / Re: The 2016/2017 freezing season
« on: December 21, 2016, 04:53:22 PM »
Note: please, if anyone can explain to me how I attach animations that not need be clicked later to work
See here, key is max 700 x 700 pixels, I think there is a max for memory size as well
https://forum.arctic-sea-ice.net/index.php/topic,1259.0.html

Thank you very much. To attach a figure that fits in, Ascat, an old friend of this forum's but not as much lately, presuming that this technology is not as revealing anymore. Images of 20th of December. I let others for the analysis

27
Arctic sea ice / Re: The 2016/2017 freezing season
« on: December 20, 2016, 04:32:57 PM »
Impressive. Lots of activity in the area of Fram and a revival of the subpolar current for the next nine days. Not expected to be a quiet start of the winter for ice pack.
Note: please, if anyone can explain to me how I attach animations that not need be clicked later to work, infinite thanks. In the meantime, the animation needs a click.

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Arctic sea ice / Re: Latest PIOMAS update (December)
« on: December 05, 2016, 05:14:20 PM »
And it looks as if almost all of the thickest ice is set to exit the Fram. If this ice were to exit the Fram through the winter and early Spring, the 2017 melt season could be epic.
With regard to exports through Fram, and in line with previous predictions brought to this forum by others, the ECMWF shows the consolidation of a powerful high pressure system in Beaufort coupled with cyclones in Eurasia and the Atlantic Ocean. This pattern persists for the whole prediction time span.
Sorry, the animation needs a click to work.

29
Arctic sea ice / Re: The 2016/2017 freezing season
« on: October 21, 2016, 01:09:22 PM »
Highly interesting! ECMWF 00z run has a bombcyclone in the Chukchi Sea at +168h. Berings Sea could see a SLP at 936 hpa in +144h. The cyclone will extend into the CAB and ESS.

As there is open, and very warm waters, in these regions the question should be what impact such a strong cyclone will have on the refreezing?

The storm has intensified in the new forecast, and passes the Bering Sea to the Arctic Ocean. Note that the wind fetch coincides with the area of the open ocean. Based on fundamental phenomena of the ocean, we would expect surface mixing as a result of waves and swells and more memorable Ekman pumping. The refreezing may be further delayed momentarily, as there is hot and salty water that came from the Bering sea.

30
Arctic sea ice / Re: The 2016/2017 freezing season
« on: October 14, 2016, 04:01:21 PM »
Is NOAA predicting a powerful Arctic Winter?
http://www.cpc.ncep.noaa.gov/products/CFSv2/htmls/glbT2me3Sea.html

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Arctic sea ice / Re: Poll: What happens after the first sea ice free arctic?
« on: September 14, 2016, 06:06:55 PM »
Notwithstanding that nothing will happen after that year that had not happened already in the previous one, I voted for 5

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Arctic sea ice / Re: The 2016 melting season
« on: September 09, 2016, 01:46:51 PM »
A heat wave is expected from the Atlantic to the North Pole within a week, with temperatures above zero degrees. Meanwhile, all the coldness flows towards the Pacific Ocean. What impact would this prediction have, if we remember that there are many gaps in the Arctic ice cap around the North Pole? And, will it begin to re-freeze the ice on the Pacific side?

My apologies for quoting myself. This is an analysis of 5-day temperature average in the Arctic ocean from cci-reanalyser.
I find it amusing that the average temperatures in many parts of the Arctic are presented above zero degrees, but I still hear talking about the beginning of the freezing season. Only we find displayed really negative temperatures are at the innermost part of the Arctic ice, and they are not too low in comparison with the climatology (anomalies). Doesn't it seem five days too early to talk about end of the melting season, at least? If not, I would appreciate an alternative perspective :)

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Arctic sea ice / Re: The 2016 melting season
« on: September 06, 2016, 05:43:45 PM »
A heat wave is expected from the Atlantic to the North Pole within a week, with temperatures above zero degrees. Meanwhile, all the coldness flows towards the Pacific Ocean. What impact would this prediction have, if we remember that there are many gaps in the Arctic ice cap around the North Pole? And, will it begin to re-freeze the ice on the Pacific side?

34
Arctic sea ice / Re: Ice free predictions and their uncertainty
« on: August 30, 2016, 06:41:32 PM »
Could have been the local dog catcher or anybody else, if they know when the snow melted. You should not judge people by their livelihood by the way. That is only part of what a person is. If it melts earlier in the year, you catch more rays for the year. I used the term kicked in, which perhaps I should have said kicked in to another gear. If NOAA and NASA believe it getting warmer faster and that its amplified in the Arctic, and you don't believe them, I really don't know what else to say.
Tigertown,
I think no one spoke negatively against your concepts. They were just modulating your opinion. Nothing shows that there are new feedback mechanisms in only three years of sampling, not even that old ones have accelerated. But as far as I understand no one has denied that these mechanisms exist and that the warming is amplified in the Arctic.

35
Arctic sea ice / Re: 2016 sea ice area and extent data
« on: August 30, 2016, 03:24:27 PM »
Did anyone miss the 'if' ???

Of course we'll miss the 'if' if you are too lazy to delete all the quoted text that isn't pertinent to your comment.

@ Neven, I will try to do so
@ Abbotisgone, I am cool, apologies didn't mean to sound like aggresive

On topic, recently, there's increasing interest towards the values of extent than simply area, among the more juvenile responders that disregarded extent in the past weeks. It is maybe the time of year when extent is switched from being less relevant to most relevant. Beat me if there was a real explanation behind, or only because it will keep falling and it is more suitable to make a goal. In reality, there are more accuracy of area now that there are no melt ponds. Extent is always as good except when more and more is closer to 15% in concentration hence the disgusting flash-unflash effects. In summary, if any there is a greater precision, if not acuracy, of area these days. However it does not feel certain goals. Lurker long-time question.

36
Arctic sea ice / Re: 2016 sea ice area and extent data
« on: August 30, 2016, 11:22:36 AM »
If this is a compaction event, does anyone know why there is a lack of light blue concentration increases internal to the pack in recent days?  We are even seeing blocs of concentration drops (light red)?
this is not compaction, this is melt out, the term compaction is not accurate IMO to describe current events.
Cannot both? More experienced commenters than us newbies show maps with ice crashed against the shores of North America. That pack is joined closely together. This is the definition of compaction. However, it is more difficult. However, two-dimensional maps aren't able to demonstrate actual melting because meting is a three-dimensional process. Concur?
Did anyone miss the 'if' ???
I don't understand your point. Is that essentieal? I am answering to magnamentis and I can ignore the "if" because I am purporting a "yes"

37
Arctic sea ice / Re: 2016 sea ice area and extent data
« on: August 30, 2016, 10:29:32 AM »
Here is the shadow CT-area report based on calibrated F18 NSIDC sea ice concentration data:

day  CT-date       NH               SH                Global
Sat 2016.6493 -170.0  2.918565  +56.9 14.809784  -113.1 17.728349
Sun 2016.6521 -109.9  2.808624  -40.2 14.769591  -150.1 17.578215
Mon 2016.6548  -52.5  2.756159  +81.7 14.851282   +29.2 17.607441
Tue 2016.6575  -57.9  2.698250  +53.4 14.904697    -4.5 17.602947


Single handed done by the CAB: -64k.

Shadow NSIDC extent is now 4.5373 dropping -172.4k. Done by the CAB (-132k), Chukchi (-29k) and ESS (-24k).

The left Wrangle arm is in flames in the attached delta image.

If this is a compaction event, does anyone know why there is a lack of light blue concentration increases internal to the pack in recent days?  We are even seeing blocs of concentration drops (light red)?

this is not compaction, this is melt out, the term compaction is not accurate IMO to describe current events.


Cannot both? More experienced commenters than us newbies show maps with ice crashed against the shores of North America. That pack is joined closely together. This is the definition of compaction. However, it is more difficult. However, two-dimensional maps aren't able to demonstrate actual melting because meting is a three-dimensional process. Concur?

38
Arctic sea ice / Re: The 2016 melting season
« on: August 19, 2016, 02:27:25 PM »
Amazing. Now can the SIA crash be sustained on a slightly weaker storm alone, with no help from 925 hPa temps? The next 2-3 days will be really interesting in that regard. It doesn't look like we're going to get a new 953 pHa storm (that's a pretty sick forecast), but instead it looks like a dipole may be on the horizon, which could be just as devastating.

From what I can see, these systems are associated with a warm front as in mid latitudes. May not this lead to an increase of the temperature up to 750 m or even 1500 m (2500-5000 feet) ?. 925 hPa or 850 hPa is not as high altitude.
This fragment is of today Canada service. Thanks to Neven, that uses this site

39
Arctic sea ice / Re: The 2016 melting season
« on: August 18, 2016, 03:06:58 PM »
What are the chances of four metre waves to reach the North Pole? There seem to be no ice cap anymore, only broken floes

40
Arctic sea ice / Re: The 2016 melting season
« on: August 12, 2016, 03:08:31 PM »
I know that this model has not very good reputation, but I would like to ask: how good are these archived images? According to these maps, we are faced with the same kind of storm


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The forum / Re: 1000 members
« on: August 10, 2016, 05:02:34 PM »
Thank you, Neven.
I am usally harmless  8)

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Hello all. I'm a new member and wanted to cast my vote. This is 4.5 to 4.75 million of km2. No other reason that the extent is not dropping as was being expected by the forum people, and extrapolating from other slower years this is what I find.
Nothing else just my first contribution to the forum. Thank you.  :)

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The forum / Re: 1000 members
« on: August 10, 2016, 12:48:37 PM »
I believe I am  ;D

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The forum / Re: 1000 members
« on: August 10, 2016, 10:52:30 AM »
Hello:
I am the user 1000.

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