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Neven

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Re: The 2016 melting season
« Reply #400 on: April 19, 2016, 07:54:52 PM »
I was focused on snow cover in Canada/Alaska, but good Lord, look at western Siberia!
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Re: The 2016 melting season
« Reply #401 on: April 19, 2016, 08:32:30 PM »

It looks like much of Western Siberia is going to have +10 to +20°C air temperature anomalies throughout this week. Much of the air above the Kara Sea will be persistently above 0°C from Saturday through Tuesday.




Neven

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Re: The 2016 melting season
« Reply #402 on: April 20, 2016, 12:23:02 AM »

It looks like much of Western Siberia is going to have +10 to +20°C air temperature anomalies throughout this week. Much of the air above the Kara Sea will be persistently above 0°C from Saturday through Tuesday.

Exactly, and the Eurasian snow cover is already disappearing at light speed:
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Re: The 2016 melting season
« Reply #403 on: April 20, 2016, 04:26:28 AM »
Back to the Beaufort.

World View, Aqua Modis band 31 night, blue palette, squashed to about 230K-272K, Beaufort and environs.

This disturbs me, and am I wrong to assume it is unprecedented?  The Anticyclone has ripped up nearly 1,000,000 KM2 of ice and continues to expand the disruption.
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Juan C. García

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Re: The 2016 melting season
« Reply #404 on: April 20, 2016, 06:22:59 AM »
This disturbs me, and am I wrong to assume it is unprecedented?  The Anticyclone has ripped up nearly 1,000,000 KM2 of ice and continues to expand the disruption.

IJIS:
12,928,117 km2(April 19, 2016)
Everyone else as speechless and terrified about this as I am?

ADS-NIPR Extent:
12,996,593 km2 (18 April)
54 days this year (50% year-to-date) have recorded the lowest daily extent.
95 days in total (87.96%) have been among the lowest three on record.

How many years are in which, on a daily basis, we have recorded 50% the lowest daily extent and 87.96% among the lowest three on record?

Seems to me that 2016 is going to be a very special year. The SIE has been very low and the remaining ice is not healthy.
Which is the best answer to Sep-2012 ASI lost (compared to 1979-2000)?
50% [NSIDC Extent] or
73% [PIOMAS Volume]

Volume is harder to measure than extent, but 3-dimensional space is real, 2D's hide ~50% thickness gone.
-> IPCC/NSIDC trends [based on extent] underestimate the real speed of ASI lost.

Tensor

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Re: The 2016 melting season
« Reply #405 on: April 20, 2016, 06:42:04 AM »
Back to the Beaufort.

World View, Aqua Modis band 31 night, blue palette, squashed to about 230K-272K, Beaufort and environs.

This disturbs me, and am I wrong to assume it is unprecedented?  The Anticyclone has ripped up nearly 1,000,000 KM2 of ice and continues to expand the disruption.

Am I wrong to assume the the breakup shown is an indication of the lack of thickness and poor condition of the ice?
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oren

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Re: The 2016 melting season
« Reply #406 on: April 20, 2016, 07:41:03 AM »
Looking at the IJIS extent chart, it seems we are tracking about one whole week earlier than the "new normal" years. And it's quite consistent. Since Chris Reynolds has shown a while ago that the way towards an ice free arctic goes through a shorter freezing season and a longer melting season, I believe this is significant. Despite the calculations that show a "Slow Transition", it seems the actual arctic could have some surprises. This year's chart of FDDs, and the early drops in extent, could cook a very interesting year.

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Re: The 2016 melting season
« Reply #407 on: April 20, 2016, 07:51:11 AM »
Looking at the IJIS extent chart, it seems we are tracking about one whole week earlier than the "new normal" years. And it's quite consistent. Since Chris Reynolds has shown a while ago that the way towards an ice free arctic goes through a shorter freezing season and a longer melting season, I believe this is significant. Despite the calculations that show a "Slow Transition", it seems the actual arctic could have some surprises. This year's chart of FDDs, and the early drops in extent, could cook a very interesting year.
... and that "one week" is far bigger than it might appear, as it gets amplified each successive day hat passes, with increased energy getting captured and the cascading effect of melt accelerating.

If there is an "bump" week of melting on the other side of the year, I'm convinced it is almost certain we'll drop below 2012, possibly by quite a lot.  It won't take an exceptional year to get there, with two extra weeks.  If we have a year like 2012, bar the door, because Wadhams may be proven right.
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Jim Hunt

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Re: The 2016 melting season
« Reply #408 on: April 20, 2016, 08:42:10 AM »
O-Buoy 14 is gradually defrosting. and an Arctic Ocean Flux Buoy  is now visible in the distance:

http://GreatWhiteCon.info/resources/arctic-sea-ice-images/winter-2015-16-images/#OBuoy14

The yellow blob in the foreground may well be Ice Tethered Profiler 89. Here's what it reveals also:
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slow wing

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Re: The 2016 melting season
« Reply #409 on: April 20, 2016, 09:26:57 AM »
Very interesting, thanks Jim.

It took me a while to reconcile the coarse & fine scales for both temperature & salinity profiles because they distort the intermediate values for each colour in going between coarse & fine, while keeping both endpoints the same.

For the example of temperature, the endpoints are  violet at -2.0oC and red at +1.8oC, applying for both the coarse and fine scales. However the fine/coarse values respectively for 0%, 20%, 40%, 60% and 80%, 100% up the colour scale are, in degrees C, -2.0 for both (0%, violet), -1.6 vs 0.0 (20%, dark blue), -1.2 vs 0.4 (40%, light blue),  -0.8 vs 0.6 (60%, light green), -0.4 vs 0.8 (80%, yellow), 1.8 for both (100%, red).

Why do they do that!? Presumably to give slightly better resolution for both plots but... ugh!

Neven

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Re: The 2016 melting season
« Reply #410 on: April 20, 2016, 10:17:49 AM »
Looking at the IJIS extent chart, it seems we are tracking about one whole week earlier than the "new normal" years. And it's quite consistent. Since Chris Reynolds has shown a while ago that the way towards an ice free arctic goes through a shorter freezing season and a longer melting season, I believe this is significant. Despite the calculations that show a "Slow Transition", it seems the actual arctic could have some surprises. This year's chart of FDDs, and the early drops in extent, could cook a very interesting year.

Indeed. I keep thinking about the perfect chronological order for a melting season to go really low or ice-free, and it looks something like this so far. If we get heavy melt ponding during May and June, I might cry.
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Re: The 2016 melting season
« Reply #411 on: April 20, 2016, 10:50:54 AM »
Looking at the IJIS extent chart, it seems we are tracking about one whole week earlier than the "new normal" years. And it's quite consistent. Since Chris Reynolds has shown a while ago that the way towards an ice free arctic goes through a shorter freezing season and a longer melting season, I believe this is significant. Despite the calculations that show a "Slow Transition", it seems the actual arctic could have some surprises. This year's chart of FDDs, and the early drops in extent, could cook a very interesting year.
... and that "one week" is far bigger than it might appear, as it gets amplified each successive day hat passes, with increased energy getting captured and the cascading effect of melt accelerating.

If there is an "bump" week of melting on the other side of the year, I'm convinced it is almost certain we'll drop below 2012, possibly by quite a lot.  It won't take an exceptional year to get there, with two extra weeks.  If we have a year like 2012, bar the door, because Wadhams may be proven right.
In that eventuality could we conclude that the ice has gone emeritus?

magnamentis

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Re: The 2016 melting season
« Reply #412 on: April 20, 2016, 10:55:37 AM »
Am I wrong to assume the the breakup shown is an indication of the lack of thickness and poor condition of the ice?

My first thought exactly. I think you're spot on while there is never only one culprit but still, the ice could not grow in thickness as usual and as a result any movement has a greater impact which will have it's consequences when it comes to Albedo reduction etc.

seaicesailor

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Re: The 2016 melting season
« Reply #413 on: April 20, 2016, 11:17:06 AM »
Am I wrong to assume the the breakup shown is an indication of the lack of thickness and poor condition of the ice?

My first thought exactly. I think you're spot on while there is never only one culprit but still, the ice could not grow in thickness as usual and as a result any movement has a greater impact which will have it's consequences when it comes to Albedo reduction etc.

We cannot know if this has happened frequently in the past but my feeling is "yes". This atmospheric pattern is very normal in the Arctic, and it is what provides mechanical energy to the  perennial Gyre and transpolar ocean currents. I am not convinced that the fact ice is thicker or thinner is a factor on the extent of cracking (actually much of the ice cracking right now is multi-year old and 2m thick).

What does the cracking induce during the melting season if May comes warm and sunny, that can be with no precedent "thanks" to AGW.

Jim Hunt

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Re: The 2016 melting season
« Reply #414 on: April 20, 2016, 12:04:13 PM »
It looks as though the Great Arctic Anticyclone of 2016 may yet have a sting in its tail:

http://GreatWhiteCon.info/2016/04/the-beaufort-gyre-goes-into-overdrive/#comment-214300

ACNFS currently suggests that next week the entrance to McClure Strait will be cleared of old ice just as the flow of (comparatively!) warm water from the Mackenzie River into the eastern Beaufort Sea starts to increase:
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oren

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Re: The 2016 melting season
« Reply #415 on: April 20, 2016, 12:40:38 PM »
Looking at the IJIS extent chart, it seems we are tracking about one whole week earlier than the "new normal" years. And it's quite consistent. Since Chris Reynolds has shown a while ago that the way towards an ice free arctic goes through a shorter freezing season and a longer melting season, I believe this is significant. Despite the calculations that show a "Slow Transition", it seems the actual arctic could have some surprises. This year's chart of FDDs, and the early drops in extent, could cook a very interesting year.

... and that "one week" is far bigger than it might appear, as it gets amplified each successive day hat passes, with increased energy getting captured and the cascading effect of melt accelerating.


If there is an "bump" week of melting on the other side of the year, I'm convinced it is almost certain we'll drop below 2012, possibly by quite a lot.  It won't take an exceptional year to get there, with two extra weeks.  If we have a year like 2012, bar the door, because Wadhams may be proven right.

Exactly.

pauldry600

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Re: The 2016 melting season
« Reply #416 on: April 20, 2016, 12:59:55 PM »
Normally I lurk on this forum each day to see all the developments and am in awe of all the graphs and photos

Today im just downright depressed.

This year it seems like really serious things are happening "up there".

None of the posts are about refreezing or cold air. Each passing day there is more and more anomalies. It saddens me.

pccp82

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Re: The 2016 melting season
« Reply #417 on: April 20, 2016, 01:07:52 PM »
I also lurk here quite often, and I want to make sure I am understanding something correctly.

with the discussion of the High pressure, does this have the effect of displacing the cold air out of the arctic?

looking at climate reanalyzer, it seems to show cold air being dragged out of the arctic into northern canada, while at the same time pulling warm air into Greenland...

In this instance, does the ice have time to recover before the sun gets too high in the sky to allow significant cooling?

magnamentis

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Re: The 2016 melting season
« Reply #418 on: April 20, 2016, 01:12:07 PM »
Looking at the IJIS extent chart, it seems we are tracking about one whole week earlier than the "new normal" years. And it's quite consistent. Since Chris Reynolds has shown a while ago that the way towards an ice free arctic goes through a shorter freezing season and a longer melting season, I believe this is significant. Despite the calculations that show a "Slow Transition", it seems the actual arctic could have some surprises. This year's chart of FDDs, and the early drops in extent, could cook a very interesting year.

... and that "one week" is far bigger than it might appear, as it gets amplified each successive day hat passes, with increased energy getting captured and the cascading effect of melt accelerating.


If there is an "bump" week of melting on the other side of the year, I'm convinced it is almost certain we'll drop below 2012, possibly by quite a lot.  It won't take an exceptional year to get there, with two extra weeks.  If we have a year like 2012, bar the door, because Wadhams may be proven right.

Exactly.

Like you i second that 100% and want to add that not only are we facing longer melt seasons as mentioned in the quoted post, but as well the average winter temps are that much lower that the ice will be thinning out and once the ice thickness high will stay below a certain level, even a "new normal" haha.. melting season will suffice to loose it all in ever shorter time. sorry for bad english as compared to native speakers, hope it's comprehensive.

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Re: The 2016 melting season
« Reply #419 on: April 20, 2016, 01:35:34 PM »
It's not a new development, it's been like this for over two decades now: the up and down of weather plus the up and down of oscillations (like El Nino) plus a general downwards trend due to more heat trapped in the system equals new record lows every few years, with some up phases in between. The only ones to be surprised should be the ones who really believed in the recovery propaganda.

The only thing that really changed is that the effects on the rest of the globe get more intense over time.
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Re: The 2016 melting season
« Reply #420 on: April 20, 2016, 02:21:00 PM »
Despite the calculations that show a "Slow Transition", it seems the actual arctic could have some surprises. This year's chart of FDDs, and the early drops in extent, could cook a very interesting year.
I don't believe in a "Slow Transition". I believe a transition between two different states will start out slow, but once a certain tipping point is reached, the transition will take place very fast and very violently. A bit like jumping off of troll ledge. You jump and your speed will increase until terminal velocity and by itself that is not an issue. The thing that is the issue is the sudden deceleration at the bottom.

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Re: The 2016 melting season
« Reply #421 on: April 20, 2016, 02:45:52 PM »
Despite the calculations that show a "Slow Transition", it seems the actual arctic could have some surprises. This year's chart of FDDs, and the early drops in extent, could cook a very interesting year.
I don't believe in a "Slow Transition". I believe a transition between two different states will start out slow, but once a certain tipping point is reached, the transition will take place very fast and very violently. A bit like jumping off of troll ledge. You jump and your speed will increase until terminal velocity and by itself that is not an issue. The thing that is the issue is the sudden deceleration at the bottom.
I think it will be less violent than you think, because there are many subsystems with their own tipping points that will be reached at different times (and some are already behind us). So while overall the development is irreversible and will become threatening when climate patterns move away from the ones favorable for humanity, there won't be a single point of violent change... just developments that seem harmless and let people get used to them - but summed up, are just as dangerous as the violent transition you spoke of.
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Re: The 2016 melting season
« Reply #422 on: April 20, 2016, 02:49:22 PM »
Quote
I don't believe in a "Slow Transition".

I don't either. The only thing propping up the Arctic Ocean right now is the lack of mixing. The heat is already there to melt the ice many times over. With an ice cover, the wind and waves cannot get at the density differences that keep the heat in place -- at depth where it is not in contact with the ice.

Quote
I believe a transition between two different states will start out slow, but once a certain tipping point is reached, the transition will take place very fast

I'm of the same opinion. The ice is in such a state that one of these years a really bad summer weather pattern will push way too much ice out the Fram Strait in a single drawn-out event. And there we'll be, unable turn things around, 80 years ahead of the warnings.

Quote
the development is irreversible and will become threatening when climate patterns move away from the ones favorable for humanity ...developments that seem harmless but summed up, are just as dangerous as the violent transition you spoke of.

That's the backup plan, the best we can hope for, and a good rationale for studying incremental change such as sea level and temperature rise, ocean pH, retreating glaciers, collapsing ice shelves and so forth.
« Last Edit: April 20, 2016, 03:51:07 PM by A-Team »

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Re: The 2016 melting season
« Reply #423 on: April 20, 2016, 03:11:19 PM »
NOAA have released their March analysis and nothing looks good:

http://www.ncdc.noaa.gov/sotc/global/201603

Some highlights:

- On March 24th, Arctic sea ice reached its maximum extent for the year at 5.61 million square miles, the lowest annual maximum extent in the satellite record. The maximum extent was 431,000 square miles below average and 5,000 square miles below the previous record that occurred in 2015, according to analysis by the National Snow and Ice Data Center based on data from NOAA and NASA.

- the March Arctic temperature over land for 66°–90°N overall was 3.34°C (6.01°F) higher than the 1981‐2010 average. This was the second highest March temperature on record for the region, 0.03°C (0.05°F) lower than the record set in 2011.

- The combined average temperature over global land and ocean surfaces for March 2016 was the highest for this month in the 1880–2016 record, at 1.22°C (2.20°F) above the 20th century average of 12.7°C (54.9°F).

- This surpassed the previous record set in 2015 by 0.32°C / (0.58°F), and marks the highest monthly temperature departure among all 1,635 months on record, surpassing the previous all-time record set just last month by 0.01°C (0.02°F).

- Overall, the nine highest monthly temperature departures in the record have all occurred in the past nine months.

-March 2016 also marks the 11th consecutive month a monthly global temperature record has been broken, the longest such streak in NOAA's 137 years of record keeping.

-  The first three months of 2016 were the warmest such period on record across the world's land and ocean surfaces, at 1.15°C (2.07°F) above the 20th century average of 12.3°C (54.1°F), surpassing the previous record set in 2015 by 0.28°C (0.50°F) and surpassing January-March 1998, the last time during this period a similar strength El Niño occurred, by 0.45°C (0.81°F).

-  January–March 2016 also marks the highest departure from average for any three-month period on record. This record has been broken for seven consecutive months, since the July–September 2015 period.
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Re: The 2016 melting season
« Reply #424 on: April 20, 2016, 03:29:18 PM »
If March's SSW is what has tipped us into the Anticyclone over Beaufort and export from Fram ( and our cold spring in the UK!!!) then will 'normal services be resumed' in May or has the imposition of this pattern set the scene for larger portions of the summer up there?

We still have the heat from Nino working its way out of the system so we ought to expect some type of impact from this as well?

The other thing has to be the lack of cold and any changes this has brought to the ice? Surely if ice spends less time under -30 temps than normal it will not end up as 'cold' as it would have??? Am I thinking straight or am I getting turned around here?
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seaicesailor

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Re: The 2016 melting season
« Reply #425 on: April 20, 2016, 03:47:39 PM »
I also lurk here quite often, and I want to make sure I am understanding something correctly.

with the discussion of the High pressure, does this have the effect of displacing the cold air out of the arctic?

looking at climate reanalyzer, it seems to show cold air being dragged out of the arctic into northern canada, while at the same time pulling warm air into Greenland...

In this instance, does the ice have time to recover before the sun gets too high in the sky to allow significant cooling?
yes and yes, but the ice would not recover, simply might melt more slowly if that happens.

seaicesailor

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Re: The 2016 melting season
« Reply #426 on: April 20, 2016, 03:59:55 PM »
If March's SSW is what has tipped us into the Anticyclone over Beaufort and export from Fram ( and our cold spring in the UK!!!) then will 'normal services be resumed' in May or has the imposition of this pattern set the scene for larger portions of the summer up there?

We still have the heat from Nino working its way out of the system so we ought to expect some type of impact from this as well?

The other thing has to be the lack of cold and any changes this has brought to the ice? Surely if ice spends less time under -30 temps than normal it will not end up as 'cold' as it would have??? Am I thinking straight or am I getting turned around here?
Does the persistent High, and the higher 500 hpa geopotential altitude have to do with, apparently, a Sudden Stratorpheric Warming (SSW) that happened in March? FWIW:

https://www.aer.com/science-research/climate-weather/arctic-oscillation

explains impact of current conditions -AO -NAO at NH level

I posted this link a couple of days ago. While aer.com seems a serious (for-profit) entity, how reliable it is I know not, but this page addresses March SSW (not sure how it works) and the current -AO and -NAO. The weather has worsened very much where I live in the way it is supposed to according to these indices.
Anyway, in May (inconclusive):

"Also the relationship between the AO and the weather across the mid-latitudes is much weaker in summer and can even be opposite of that in winter.  For now the best forecast is probably one of persistence, which would favor an overall negative AO into early May"

PS. Just realized the analysis has aged a bit being from April 11

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Re: The 2016 melting season
« Reply #427 on: April 20, 2016, 04:00:38 PM »
I'm of the same opinion. The ice is in such a state that one of these years a really bad summer weather pattern will push way too much ice out the Fram Strait in a single drawn-out event. And there we'll be, unable turn things around, 80 years ahead of the warnings.
Even if the ice would completely melt out by September, it would still return in the winter, and people would just get used to it... many would only "get it" when the changes harm them personally.

https://xkcd.com/1321/
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Re: The 2016 melting season
« Reply #428 on: April 20, 2016, 04:07:54 PM »
Am I wrong to assume the the breakup shown is an indication of the lack of thickness and poor condition of the ice?

My first thought exactly. I think you're spot on while there is never only one culprit but still, the ice could not grow in thickness as usual and as a result any movement has a greater impact which will have it's consequences when it comes to Albedo reduction etc.

We cannot know if this has happened frequently in the past but my feeling is "yes". This atmospheric pattern is very normal in the Arctic, and it is what provides mechanical energy to the  perennial Gyre and transpolar ocean currents. I am not convinced that the fact ice is thicker or thinner is a factor on the extent of cracking (actually much of the ice cracking right now is multi-year old and 2m thick).

What does the cracking induce during the melting season if May comes warm and sunny, that can be with no precedent "thanks" to AGW.

I wonder if another factor to consider with the amount cracking is the temperature of the ice, since colder ice is much stronger than warmer ice? Not sure who posted it, but I believe it was something like -20C ice is 5x stronger than -10C ice, so if the warmer temps over the winter had an effect not only on ice growth, but on the ice temperatures as well, then it could lead to increased cracking. I'm really speculating here though, I don't have any evidence,

And like the other lurkers who check in here daily, I'm finding this year to be really worrying. I knew the ice could melt out this fast, but I somehow didn't think it would, that it would take maybe a few more years. I also don't think it'll be a slow transition, mainly because of once it's a blue sea early enough it'll accumulate so much more solar energy, and open water will get waves, which will pull up more heat from below, etc.

The other disconcerting things about a near future abrupt transition are a) how radically a warmer arctic is already messing up the jet stream and weather patterns (and therefore global agriculture) and b) how much a much warmer arctic could accelerate Greenland Ice Sheet melt, now that we're starting to understand how much surface melt and albedo changes affect ice loss.

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Re: The 2016 melting season
« Reply #429 on: April 20, 2016, 04:14:23 PM »
I'm of the same opinion. The ice is in such a state that one of these years a really bad summer weather pattern will push way too much ice out the Fram Strait in a single drawn-out event. And there we'll be, unable turn things around, 80 years ahead of the warnings.
Even if the ice would completely melt out by September, it would still return in the winter, and people would just get used to it... many would only "get it" when the changes harm them personally.

https://xkcd.com/1321/

Oh man, that xkcd is too true. Maybe it'll become non-taboo for most people when people have to start abandoning Miami or something, or when there's a giant financial crash once everyone owning coastal properties and the banks holding the mortgages realize that the properties and the mortgages will soon be worthless. I feel like a lot of people don't want to talk about it because it's too depressing, rather than they don't care about it.

Buddy

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Re: The 2016 melting season
« Reply #430 on: April 20, 2016, 04:37:42 PM »
Quote
I feel like a lot of people don't want to talk about it because it's too depressing, rather than they don't care about it.

It is like people during the "tech crash" from 2000 - 2003......they stopped opening their retirement account statements because they didn't want to face the truth, it was too painful.

When insurance rates for homes eventually AREN'T subsidized by state or federal governments....those housing prices are going to GO DOWN SIGNIFICANTLY.  When the real cost to insure them is born by the house owner....it will be too expensive.

http://www.tampabay.com/news/business/banking/starting-april-1-homeowners-to-see-subsidized-flood-insurance-phased-out/2223297
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A-Team

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Re: The 2016 melting season
« Reply #431 on: April 20, 2016, 04:56:37 PM »
Quote
Even if the ice would completely melt out by September, it would still return in the winter

Snow on thin ice, having held the heat in, gone again late-spring. The problem with vanishing ice in summer is that is when the Arctic performs its planetary refrigeration. Without reflection of solar and the equatorial gradient, the atmosphere will become quickly unhinged.

crandles

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Re: The 2016 melting season
« Reply #432 on: April 20, 2016, 05:40:46 PM »
Quote
Even if the ice would completely melt out by September, it would still return in the winter

Snow on thin ice, having held the heat in, gone again late-spring. The problem with vanishing ice in summer is that is when the Arctic performs its planetary refrigeration. Without reflection of solar and the equatorial gradient, the atmosphere will become quickly unhinged.

I agree a small difference now could widen to a large difference late in the melt season due to albedo effects. Volume does not seem all that much lower than past seasons so I doubt a huge effect this year. Volume products could be wrong so I don't completely rule it out.

Even if we did get an exceptional melt this year:
The ice is only going to vanish towards the very end of the melt season, it isn't going to vanish by the start of summer. Most snowfall is in autumn, and with no ice, that cannot be supported, so there is little snow for insulation, so the ice thickens quickly. Following winter's ice may be thicker than normal but with little snow. By the second year almost everything is likely back to near to trend.

While the summer albedo feedback is destabilising, the winter thickness growth feedback is stabilising and seems likely to overwhelm the summer albedo feedback destabilising effect.

Small trend changes causing weather pattern changes causing species loss and consequent effects  seems more concerning to me than some flip in Arctic sea ice state to another for the near term. Longer term ocean temp increases might make some sort of flip may well become more of a risk but I doubt such a risk is imminent.

(There are a couple of papers supporting this Tietsche et al and Schröder and Connolley. If other models behaved differently, I think we would know about it.)

AmbiValent

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Re: The 2016 melting season
« Reply #433 on: April 20, 2016, 06:06:12 PM »
crandles, even if a new equilibrium was reached, it would still mean repeated meltouts or near-meltouts. And that would mean that in areas of the Arctic where the ice melts earlier there will be excess heat that would increase melting processes in the Permafrost regions and Greenland. And either would have bad consequences...
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Juan C. García

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Re: The 2016 melting season
« Reply #434 on: April 20, 2016, 06:10:55 PM »
I'm of the same opinion. The ice is in such a state that one of these years a really bad summer weather pattern will push way too much ice out the Fram Strait in a single drawn-out event. And there we'll be, unable turn things around, 80 years ahead of the warnings.
Even if the ice would completely melt out by September, it would still return in the winter, and people would just get used to it... many would only "get it" when the changes harm them personally.

The first question is how much Arctic sea ice can we loose this summer and the second question is how much warmer does Greenland will be. It does not need to be a great Greenland ice melt. Just enough to make sure that the process of losing coastal cities is starting and I hope this will trigger that the humanity will care about AGW, the prevention and the adaptation.
Which is the best answer to Sep-2012 ASI lost (compared to 1979-2000)?
50% [NSIDC Extent] or
73% [PIOMAS Volume]

Volume is harder to measure than extent, but 3-dimensional space is real, 2D's hide ~50% thickness gone.
-> IPCC/NSIDC trends [based on extent] underestimate the real speed of ASI lost.

Archimid

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Re: The 2016 melting season
« Reply #435 on: April 20, 2016, 06:43:05 PM »
Quote
While the summer albedo feedback is destabilising, the winter thickness growth feedback is stabilising and seems likely to overwhelm the summer albedo feedback destabilising effect.

How can you possibly know that? To the best of my knowledge, there has been ice cover on the arctic for a very long time. If  the sea ice disappears, the Arctic  will be in a completely different initial state for the freezing season. For as long as it has been studied, refreezing happens with millions of square kilometers of ice already present. That means that ocean temperature will be very different, humidity will be different, wave action and currents will be different and who know how many other factors.

 Granted the Arctic is dark for a very long time, so some refreezing  will probably occur at some point but it will be very late in the season and the warmer waters will melt it very fast come spring. And that's only the first year. After that the waters will get warmer with the longer summers, delaying refreeze even more, if at all.
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jdallen

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Re: The 2016 melting season
« Reply #436 on: April 20, 2016, 07:21:50 PM »
Quote
Even if the ice would completely melt out by September, it would still return in the winter

Snow on thin ice, having held the heat in, gone again late-spring. The problem with vanishing ice in summer is that is when the Arctic performs its planetary refrigeration. Without reflection of solar and the equatorial gradient, the atmosphere will become quickly unhinged.

<snippage>
Even if we did get an exceptional melt this year:
The ice is only going to vanish towards the very end of the melt season, it isn't going to vanish by the start of summer. Most snowfall is in autumn, and with no ice, that cannot be supported, so there is little snow for insulation, so the ice thickens quickly. Following winter's ice may be thicker than normal but with little snow. By the second year almost everything is likely back to near to trend.

While the summer albedo feedback is destabilising, the winter thickness growth feedback is stabilising and seems likely to overwhelm the summer albedo feedback destabilising effect.
<more snippage>

I disagree with your first point pretty strongly and your second mildly.  For one thing, both depend on status quo ante - that conditions besides the ice or lack thereof will stay the same.  They won't.  They aren't now.  Late open water in the Arctic translates into the availability of both heat and moisture required for snow.  It will happen, as low snowfall in winter is a direct product of the lack of them.  You can't depend on a lack of snow to permit robust freezing.

I'm dubious of your assertion that winter freezing will overwhelm summer  low albedo.  What would be more correct is to compare summer heat uptake with winter heat loss from the ocean.  Ice is a buffer for that, but after the first 50CM or so, it becomes a major hindrance to heat loss.  So, as a result not enough of that low albedo driven heat accumulation will get re-radiated. 

I think that is exactly what we see currently - the cumulative effect of multiple seasons of additional residual retained heat, accumulated in the system.  So in short, I don't think winter refreeze will save us from continued more precipitous summer decline, until we drop down to ~1,000,000 KM2 +/-. 

Once we reach that I think it may be some decades before enough heat accumulates such that the sea ice is eradicated entirely in summer, leaving just the various rapidly decaying Arctic ice caps, such as Greenland.  But getting there now, I think may be quite precipitous - much faster than most of us - including me - believed previously.  Our error I think was overlooking winter warming.
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jdallen

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Re: The 2016 melting season
« Reply #437 on: April 20, 2016, 07:28:19 PM »
Quote
Even if the ice would completely melt out by September, it would still return in the winter
...The problem with vanishing ice in summer is that is when the Arctic performs its planetary refrigeration. Without reflection of solar and the equatorial gradient, the atmosphere will become quickly unhinged.
And here I think we have the most apt and succinct characterizations yet, of what I think we are about to experience with our climate.
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jdallen

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Re: The 2016 melting season
« Reply #438 on: April 20, 2016, 07:32:59 PM »
O-Buoy 14 is gradually defrosting. and an Arctic Ocean Flux Buoy  is now visible in the distance:

http://GreatWhiteCon.info/resources/arctic-sea-ice-images/winter-2015-16-images/#OBuoy14

The yellow blob in the foreground may well be Ice Tethered Profiler 89. Here's what it reveals also:
Thank you Jim.  I'm particularly concerned about the warm layer setting up (-0.4C) between 50 and 75 M in depth.  Sitting right there is reservoir with enough heat to chew up 20-30CM of ice, just on it's own, if it got transferred to the ice. Implications anyone?
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jdallen

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Re: The 2016 melting season
« Reply #439 on: April 20, 2016, 07:41:46 PM »
Am I wrong to assume the the breakup shown is an indication of the lack of thickness and poor condition of the ice?

My first thought exactly. I think you're spot on while there is never only one culprit but still, the ice could not grow in thickness as usual and as a result any movement has a greater impact which will have it's consequences when it comes to Albedo reduction etc.

We cannot know if this has happened frequently in the past but my feeling is "yes". This atmospheric pattern is very normal in the Arctic, and it is what provides mechanical energy to the  perennial Gyre and transpolar ocean currents. I am not convinced that the fact ice is thicker or thinner is a factor on the extent of cracking (actually much of the ice cracking right now is multi-year old and 2m thick).

What does the cracking induce during the melting season if May comes warm and sunny, that can be with no precedent "thanks" to AGW.

I wonder if another factor to consider with the amount cracking is the temperature of the ice, since colder ice is much stronger than warmer ice? Not sure who posted it, but I believe it was something like -20C ice is 5x stronger than -10C ice, so if the warmer temps over the winter had an effect not only on ice growth, but on the ice temperatures as well, then it could lead to increased cracking. I'm really speculating here though, I don't have any evidence,

And like the other lurkers who check in here daily, I'm finding this year to be really worrying.

<SNIPPAGE>
That would have been me, among others. Yes, ice loses significant mechanical strength as it warms, and I think that is a factor in what we are seeing in the Beaufort and elsewhere this year. The Beaufort in particular is germane because that shattered expanse contains by some estimations close to a third of the remaining 3+ year old MYI.

Your concern is well founded.
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Tor Bejnar

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Re: The 2016 melting season
« Reply #440 on: April 20, 2016, 07:49:54 PM »
Ignoring "the atmosphere will become quickly unhinged" bit for a starter:  I think winter open-water heat loss followed by ice growth will keep the Arctic Ocean in a moderately static cycle of losing more and more ice cover (& volume) during the summer and getting most of it back in the winter.

Now bringing back "the atmosphere will become quickly unhinged" bit:  At some date this unhinged weather will reach a mostly ice-free Arctic and mix the reservoir of warm deep water with the less dense surface water, and - presto - a year-round functionally ice-free Arctic Ocean.
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crandles

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Re: The 2016 melting season
« Reply #441 on: April 20, 2016, 08:08:31 PM »
Quote
While the summer albedo feedback is destabilising, the winter thickness growth feedback is stabilising and seems likely to overwhelm the summer albedo feedback destabilising effect.

How can you possibly know that? To the best of my knowledge, there has been ice cover on the arctic for a very long time. If  the sea ice disappears, the Arctic  will be in a completely different initial state for the freezing season. For as long as it has been studied, refreezing happens with millions of square kilometers of ice already present. That means that ocean temperature will be very different, humidity will be different, wave action and currents will be different and who know how many other factors.

 Granted the Arctic is dark for a very long time, so some refreezing  will probably occur at some point but it will be very late in the season and the warmer waters will melt it very fast come spring. And that's only the first year. After that the waters will get warmer with the longer summers, delaying refreeze even more, if at all.

I am not saying there isn't a downward trend; there is and it is more pronounced in Summer than Winter.

I think I  expressed what you quoted very badly. 'likely to overwhelm' was the wrong phase which might appear to imply the summer albedo instability will disappear as it is overwhelmed. It won't disappear, it will remain dominant in summer and probably grow in strength.

While I expect strength of both to grow, I don't expect the summer albedo instability to grow and overwhelm the winter thickness growth feedback such that a flip in state becomes possible at least not for some considerable time.

Sorry I expressed that badly.

How do I reach such a conclusion?
If you are concerned about lots of factors potentially changing, modelling the important physics seems a sensible place to start. I gave references for 2 different models that tried instantaneous removal of sea ice. As I said, if other models behaved differently, I think we would know about it.

If you think there are bound to be important factors not included in the models, why would this be? I would expect modellers to try to include the important physics in their models first, but perhaps there are some things that are difficult to model. Lots of models doing wildly different things would be a bad sign. However,



shows lots of models (and other graphs will show lots more models) and most (if not all where we can see) show slowdown in rate of ice loss as ice approaches zero. How many show some sort of flip behaviour?

The models have wildly different levels of ice but their behaviour seems similar. To me, this adds to a sense of overall stability in the system.

I don't think this means there is zero chance of a flip between different states but I would suggest it makes it unlikely rather than likely.

crandles

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Re: The 2016 melting season
« Reply #442 on: April 20, 2016, 08:36:08 PM »


This seems pretty hard to overcome to me.

The growth rates will all be lower with milder temperatures but the shape remains. Also if there was a significant ocean warming effect, wouldn't we expect to see rapid ice extent growth delayed by more than about a week that we have seen so far?

With the graph shape above, losing a week so far and maybe another week over the next decade or two, isn't going to affect the maximum ice volume much. The main part of the volume loss in past decades has been thick multi-year ice. With that gone, any more ice melted in summer tends to mainly grow back in winter.

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Re: The 2016 melting season
« Reply #443 on: April 20, 2016, 09:04:19 PM »


This seems pretty hard to overcome to me.

The growth rates will all be lower with milder temperatures but the shape remains. Also if there was a significant ocean warming effect, wouldn't we expect to see rapid ice extent growth delayed by more than about a week that we have seen so far?

With the graph shape above, losing a week so far and maybe another week over the next decade or two, isn't going to affect the maximum ice volume much. The main part of the volume loss in past decades has been thick multi-year ice. With that gone, any more ice melted in summer tends to mainly grow back in winter.

I suspect you're not taking into account how aggressive the albedo loss feedback is, the main game changer will be when surface melt starts in a significant fashion at or before the peak of insolation comes instead of after. I agree a week of more open ocean towards the end of the melt season doesn't really matter much as the energy just isn't there.

Once you start getting that energy from peak insolation being absorbed instead of bounced away is when you'll see the tipping point in action.

jdallen

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Re: The 2016 melting season
« Reply #444 on: April 20, 2016, 10:17:13 PM »

This is way to simple a model to use to effectively support your conclusion, I think.  Air temperature?  Sea water temperature?  Snow cover?  Age of the ice? - off the top of my head.

Too many variables that aren't referenced here.
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Nick_Naylor

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Re: The 2016 melting season
« Reply #445 on: April 20, 2016, 10:24:54 PM »
Quote
Even if the ice would completely melt out by September, it would still return in the winter
...The problem with vanishing ice in summer is that is when the Arctic performs its planetary refrigeration. Without reflection of solar and the equatorial gradient, the atmosphere will become quickly unhinged.
And here I think we have the most apt and succinct characterizations yet, of what I think we are about to experience with our climate.

I worry about the rate of heat escaping the Arctic after a summer where enough ice is lost so that seawater temperatures are significantly higher than Earth has seen in recent millennia. It's not too hard to remember what happened after the 2012 melt season, when Sandy took the unprecedented left hook into the US Northeast coast. How much more warming before Sandy looks like a mere warning?

oren

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Re: The 2016 melting season
« Reply #446 on: April 20, 2016, 10:46:47 PM »
All of the above was hotly debated a while ago in the "Slow Transition" thread started by Chris Reynolds. Basically, according to models even a totally ice-free arctic will bounce back in the following years, as the winter contains enough freezing degree days (FDDs) to recreate first-year ice of almost the same thickness regardless of initial conditions. So a "bad luck" year that melted all the ice would not cause a tipping point. Hence a slow transition to an ice-free state and not an irrevocable meltdown. At the time I thought the work was very convincing at my basic level of knowledge, but still felt it was missing something in its assumptions.

I didn't mean to start a whole theoretical discussion when I referenced that important work (maybe the thread should be revived? Or hopefully Chris will summarize it better than my poor efforts here), I just meant to point out that maybe this year might provide an example of where the assumptions could be wrong. Total number of FDDs was much lower than normal, and the melting season seems to have started much earlier than normal.

Archimid

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Re: The 2016 melting season
« Reply #447 on: April 20, 2016, 11:01:35 PM »

While I expect strength of both to grow, I don't expect the summer albedo instability to grow and overwhelm the winter thickness growth feedback such that a flip in state becomes possible at least not for some considerable time.


I disagree.  If 0 sea ice volume is reached at any point,  it will only refreeze to a maximum volume of around 15k KM3. Evenly spread over the whole arctic that's  an average ice thickness of about 1m. A 1 m  thickness ice will melt by June, in years like this one, maybe even May. So once 0 or functionally close to 0 is reached, the total albedo increase will be much higher the following year.



Quote

How do I reach such a conclusion?
If you are concerned about lots of factors potentially changing, modelling the important physics seems a sensible place to start. I gave references for 2 different models that tried instantaneous removal of sea ice. As I said, if other models behaved differently, I think we would know about it.


My fear in this regard is that all models are made with the assumption of having an ice cap in the north pole. Having no ice will to quote A-Team.  "become quickly unhinged". So many of the most influential variables and proceses in the models won't be even valid. Only the big forcings like  the Sun and its incidence on the Arctic and local geography will remain the same.  This, I think, will render the models useless.


Quote

If you think there are bound to be important factors not included in the models, why would this be? I would expect modellers to try to include the important physics in their models first, but perhaps there are some things that are difficult to model.

Of course, but they can not include physical phenomena that have never occurred, because there has always been(as far as we are concerned)  a north pole covered in ice.

Quote
Lots of models doing wildly different things would be a bad sign. However,



shows lots of models (and other graphs will show lots more models) and most (if not all where we can see) show slowdown in rate of ice loss as ice approaches zero. How many show some sort of flip behaviour?

None, but none of them start with an arctic at 0 ice, and if they do, they can only be wild speculation, because the initial conditions will be very different and unpredictable(?).
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Archimid

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Re: The 2016 melting season
« Reply #448 on: April 21, 2016, 12:06:29 AM »
All of the above was hotly debated a while ago in the "Slow Transition" thread started by Chris Reynolds. Basically, according to models even a totally ice-free arctic will bounce back in the following years, as the winter contains enough freezing degree days (FDDs) to recreate first-year ice of almost the same thickness regardless of initial conditions. So a "bad luck" year that melted all the ice would not cause a tipping point. Hence a slow transition to an ice-free state and not an irrevocable meltdown. At the time I thought the work was very convincing at my basic level of knowledge, but still felt it was missing something in its assumptions.

I didn't mean to start a whole theoretical discussion when I referenced that important work (maybe the thread should be revived? Or hopefully Chris will summarize it better than my poor efforts here), I just meant to point out that maybe this year might provide an example of where the assumptions could be wrong. Total number of FDDs was much lower than normal, and the melting season seems to have started much earlier than normal.

Do you have a link to that thread? I searched but could't find it. If the reason they concluded it will be  a slow transition was the freezing degree days, it might need to be reopened.
http://cires1.colorado.edu/~aslater/ARCTIC_TAIR/index_80_t2m.html
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jdallen

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Re: The 2016 melting season
« Reply #449 on: April 21, 2016, 12:51:40 AM »
None, but none of them start with an arctic at 0 ice, and if they do, they can only be wild speculation, because the initial conditions will be very different and unpredictable(?).
Wild speculation and wildly unpredictable.  Except when it isn't. That I think is where A-team's "Unhinged" comes from.  Energy will be trying to redistribute itself around the system without the previous stable heat engines to move it.  Some places will develop new semi permanent features (like the RRR of North Pacific fame).  Other places may find things akin to trying to predict the topology of the surface of a boiling pot. The Caribbean and Eastern Seaboard coastlines of N. America may fall into the later category.

I think it is true the Arctic will not be permanently ice free for some time to come, as there will be sufficient variation in weather to permit summers cool enough to retain ice.  In that regime though, we will look back at years like 2012 as "good" ones.

There will be a lot more bleed off of heat from open water as there was with 2012.   But the problem of hoping for that, is that there are other years like 2011 with only marginally (about 1.8 million more KM2 of ice) greater extent.  I don't thing the lower extent of 2012 in fall was what led to 2013.  Both had over 9 million KM2 of open water to radiate from.  What saved 2013 was lucky weather, not extra heat loss.
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