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Messages - Jim Williams

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1
I always vote 0.0 in these polls.  It's kind of a rejection of the theory they are based upon.  I do not expect to be right in any particular poll, but I do expect to be suddenly right in one of them.

I am convinced that the freshwater lens and the halocline will at some point collapse, and that at that time the ice will suddenly disappear.  I don't know when this will happen, or even if it will happen in Summer, but I do think it will be rather soon.  Thus, I am always voting for a sudden end without any idea when.  Until then the ice will erode fairly slowly.

If your stance is that nihilistic, maybe you shouldn't vote? Basically, you're saying: I think your poll is stupid, so I'm going to cast an extreme vote, without making an effort of trying to understand what's going on, as if there won't be plenty of people voting low when they truly see the signs on the wall (warm winter, low volume, extremely fast SIE decline in April and May, massive melt pond formation, etc).

No wonder poll results are always skewed so low. And all that time I thought it was climate risk deniers doing it on purpose 'to make the alarmists look dumb'.

Sad.
I did at first consider not voting, and not voting is an option...but then you are rejecting a viewpoint in your social statistic.  (All this is is a socal statistic.)

I am going to be right.  I just don't know when.

As far as being Nihilistic...no, but that is a matter for discussion on some religious forum, perhaps Buddhist, not here.

2
I always vote 0.0 in these polls.  It's kind of a rejection of the theory they are based upon.  I do not expect to be right in any particular poll, but I do expect to be suddenly right in one of them.

I am convinced that the freshwater lens and the halocline will at some point collapse, and that at that time the ice will suddenly disappear.  I don't know when this will happen, or even if it will happen in Summer, but I do think it will be rather soon.  Thus, I am always voting for a sudden end without any idea when.  Until then the ice will erode fairly slowly.

3
Arctic sea ice / Re: The 2017 melting season
« on: July 08, 2017, 10:22:40 PM »
Is there really much doubt about the next hundreds and thousands of years?
https://climate.nasa.gov/system/resources/detail_files/24_co2-graph-021116-768px.jpg

(Apologies for taking another step down this OT trail.)

The only real doubts are about the extent and duration of this thawing season.

See!  Back on Topic!

4
Arctic sea ice / Re: The 2017 melting season
« on: July 08, 2017, 09:42:50 PM »
We're watching the Warm Arctic Cold Continents (or Maritime Arctic) play out here.  The only questions are how warm and how cold.  I'm betting the land isn't all that cold.

5
Arctic sea ice / Re: IJIS
« on: July 06, 2017, 09:15:18 PM »
IJIS extent is still hanging way up, from what i expected but there's still plenty of time for the halocline to break properly.

Given recent trends (especially last winter), I'd say that the halocline has at least until late October.  I wouldn't put November out of consideration.

6
Arctic sea ice / Re: 2017 sea ice area and extent data
« on: July 04, 2017, 07:45:14 PM »
<snip, off-topic, and yet again, I would like to urge others as well to stay on-topic, be short if possible, and do not be lazy when quoting others, but cut out everything except the thing you're responding to; N.>

7
Arctic sea ice / Re: The 2017 melting season
« on: July 04, 2017, 07:40:39 PM »
... Extensive regions of the Arctic Ocean have been seasonally ice free for years; the low albedo season overlaps poorly with insolation season ...
I fear for what will happen when the planet fails to dodge that particular bullet, as I suspect it will be another irreversible* tipping point.
(* At least in terms of timescales comparable to civilisation as we know it.)

The planet will continue to orbit the Sun, as always.

<Bill isn't referring to what will happen to the planet; N.>

8
Arctic sea ice / Re: The 2017 melting season
« on: July 04, 2017, 07:33:18 PM »
The "soup" season.

It has been an ocean climate since December 21, 2015.  Let's just wait until Summer is over and see what the ice does then.

9
Arctic sea ice / Re: 2017 sea ice area and extent data
« on: July 02, 2017, 06:16:37 PM »
What about if the minimum average and/or minimum is in October, not September?

I'll change the text again when that happens.

But yes, the poll thread would be the right place to discuss nomenclature and definitions, as this thread is about sea ice area and extent data.

Fine, but I will be watching the area and extent on December 31, since I think whenever the end comes the time of year isn't going to matter.

10
Arctic sea ice / Re: 2017 sea ice area and extent data
« on: July 02, 2017, 12:38:04 AM »
What is an "average minimum"? 

You're right, that's not very clear. I'll change that.

All I try to do, is explain that there are two polls, one for the September average (that month being the month of the minimum, when the Arctic sea ice pack is smallest) and one for the daily minimum. This is confusing to a lot of people, just like the difference between area and extent is.

The September average is best-known because the NSIDC has used it consistently for many years now (it's also used for the SIPN sea ice outlook). But people enjoy watching the changes on a daily basis and prefer not to wait until the first week of October to find out what the September minimum was. Hence the popularity of JAXA, formerly known as IJIS.

That's why we have a poll for both measures.

What about if the minimum average and/or minimum is in October, not September?

11
Arctic sea ice / Re: The 2017 melting season
« on: June 27, 2017, 02:42:29 AM »
Finally, remember - the words of people on this forum don't really change the September outcome. It only seems that way  ;)

I had to laugh when I realized you may be wrong about this.  The actual raw data is pretty sparse, and I suspect that we do in fact influence at least some of the researchers.

12
Arctic sea ice / Re: The 2017 melting season
« on: June 27, 2017, 02:32:41 AM »
...The thing is: the solstice comes at the same date always, give or take one day, so that delay means for sure more ice in September

Though I'd agree with everything else, I'd have to doubt this one point.  Insolation is only the most important fact until it suddenly doesn't matter much at all.  At some point the maritime climate takes control, and it is the storms and waves that count.

I'm not saying you are wrong about anything other than your assertion of "for sure."

13
Arctic sea ice / Re: The 2017 melting season
« on: June 22, 2017, 05:54:29 PM »
P.S. I think we should never underestimate ocean mixing. Water is most dense at ~4C iirc, which means, colder water in calm conditions form up a layer on top of any +4C water, protecting the ice from a bit-deeper warmer waters. Ice itself forms such a layer directly under it, via bottom melting a little bit to make it happen, creating equilibrium state at the solid-liquid border. And then, whereever there is just 20-meters-thick layer of +4C water not far from surface - especially if it's less than 50 meters deep for such layer to exist, - mixing the column can melt 1 meter of ice real quick. Difference in density is very small, so it doesn't take much wave action to mix it up well. Storms obviously do it best, but even strong winds acting upon some openings between ice fields mix it up significantly already. And if it's more than just 20 meters of +4C water layer, - at places there is times more, - then even MYI fields can "poof" away.

This is exactly what I expect to happen to the entire Arctic Ocean at some point, but the interplay between wind, leads in the ice, and rising water vapor is so complex and chaotic that there is no way to tell when it will happen.  I'm just convinced that at some point the heat in the sea rises and rather suddenly melts the ice -- all of it.

14
Arctic sea ice / Re: IJIS
« on: June 21, 2017, 04:17:08 PM »
It looks like in two days we can have a four-way tie for second place!  ::)

I'm not sure what the error range for these measurements are, but I bet we already have a five-way tie for first place.

15
...But about 36% of the June poll responses suggest that 2017 will be at or below the 95% CI for this model....
You have to understand that there are a fair number of us who are convinced that eventually the fresh water lens will get stirred away, and with that the ice will simply go away too (without regard to time of year).  Our problem is that we don't know when this will happen.  So I, for example, think a prediction of a zero ice minimum is perfectly reasonable every year since I expect it will happen some year soon.

For me trends are very interesting, but also not at all indicative.  If you could give me better real data on the state of the halocline I would be much indebted.

16
Arctic sea ice / Re: The 2017 melting season
« on: June 17, 2017, 07:11:41 PM »
Hi Neven!

Can we divide the 2017 melting season into "Ground Truth," and "projections" please?  I might suggest further dividing "projections" into "less than 6 days," and "other crap."

17
Arctic sea ice / Re: The 2017 melting season
« on: June 10, 2017, 05:03:54 PM »
foehn wind north of Greenland is producing 8 to 9 degree temperature is the from just above ground level to 1.5 km up. With above zero temperatures over near half of the CAB at this altitude and significant tpw and rh starting to get right into the centre of the basin, Atmospheric energy transport looks to really be ramping up and I suspect there is significant rainfall happening over parts of Greenland and Svalbard. And perhaps the caa.
https://earth.nullschool.net/#2017/06/10/0900Z/wind/isobaric/850hPa/overlay=temp/winkel3=324.67,90.87,666/loc=-31.031,84.402

My understanding of airborne humid energy transport is a bit limited, but I think you just told me that the Maritime Climate just arrived for this year.

18
Arctic sea ice / Re: What the Buoys are telling
« on: May 31, 2017, 11:38:21 PM »
Even more OT: My experience of firn is limited to the Alps, I only know the North from what I read on ASIF (and its links and searches inspired by what I read here).

My notion of firn, comes from the firn line (https://www.google.com/search?q=firn+line+glacier+definition&rlz=1C1CHFX_enUS590US590&oq=firn+line&aqs=chrome.2.69i57j0l5.23591j0j7&sourceid=chrome&ie=UTF-8).  Probably much the same as in the Alps.

The firn line is where above it the glacier is adding material, and below it the glacier is losing material.

I'm guessing that the use of the term firn here has some sort of relationship -- but I must admit to not understanding it.

19
Arctic sea ice / Re: How soon could we go ice free?
« on: May 31, 2017, 09:15:23 PM »
Long before we get to areas of uninhabitability...
While I basically agree with you I think I would say "general uninhabitability" here rather than "areas."  I think there are a few "hot spots" where we might see significant die-offs.

20
Arctic sea ice / Re: How soon could we go ice free?
« on: May 31, 2017, 08:11:03 PM »
I don't quite know how the conversation got here, but the usual solution warm blooded animals use for both extreme heat and extreme cold is to burrow underground where the temperatures tend to be much more consistent.

This has already been happening in several places, such as Montreal and Australia.

21
Since we are heavily loaded for this year, I'm in good company.  Just a little doomier than most.

98-18 for this year.  That is 92% believing it will happen this year.  YOU are in the minority.

I always believe it will happen "this year," but I know that every year is a guess.  All I am sure of is that when it happens it will happen suddenly.

22
Arctic sea ice / Re: 2017 sea ice area and extent data
« on: May 30, 2017, 10:48:37 PM »
I'm beginning to think I want to know the total linear kilometers of cracks in the ice, and a comparison with previous years.  I think that would tell us a lot, but I haven't a clue how to go about it.

Even defining it could get hard.  Does one just measure the polynya, or do you measure the circumference of each block?

23
Arctic sea ice / Re: How soon could we go ice free?
« on: May 30, 2017, 10:34:20 PM »
I've just discovered Guy Mcpherson and the positive feedbacks scare me that they will accelerate fast enough with a BOE and kill us all within a year.

Don't take what McPherson says at face value. He's more or less on the other extreme side of the spectrum that climate risk deniers are on. The latter believe there is 0% chance of anything bad happening because of AGW, McPherson and his followers believe that there is a 100% chance of catastrophe (and real soon too).

At least, that was my interpretation when I read/watched some of McPherson's stuff a couple of years ago. Data is skewed towards the absolute extreme and beyond.

Most of the members of the ASIF community take AGW seriously, but not to the point where they think everything is going to end the day after tomorrow. Some think it will happen later, others think/hope the worst may still be averted. I (choose to) belong to that latter group.

I'm really sorry for my posting. It's just that im terrified a  BOE could really destabilise the planet. That and climate change seems to be here already and speeding things up.

I really don't think we have a year left due to abrupt warming and some runaway effects stacking up.

I bought a house on the hill overlooking Boston 30 years ago expecting to have valuable oceanfront property, and while I still expect that to happen I despair of it doing so in my lifetime.

The sea level might start rising a foot a year within the next few years, but only poor people will notice.

24
Arctic sea ice / Re: How soon could we go ice free?
« on: May 30, 2017, 10:24:08 PM »
(Peregrine falcons love New York)

So did the doves (pigeons) before those damn predators showed up.

25
Arctic sea ice / Re: How soon could we go ice free?
« on: May 29, 2017, 08:35:19 PM »
Based on the current weather forceast and low ice volume (I've been very depressed over this since April) could we be ice free by the end of June?

Suggestion: read many of the many awesome past threads here discussing this very thing, and you are guaranteed to learn much. At any rate, ice-free by June? The answer depends in part on how one defines the term "ice free", but as it's normally understood, there is a 0% chance of this happening this year. The same answer goes for July and August and--at this point--September.

I don't agree with the September part that there is 0% chance. The long-term trend get's closer to zero each year, april and may aren't very good predictors, but the ice does look bad. If we get a 'perfect' melting season, the arctic could be ice free i guess.

I still think we will break a lot of records this year, but ice free is unlikely, but not impossible yet

one would have to put the volume in to account which more or less tells how much energy will be needed to get rid of it all and volume numbers, albeit decreasing, are simply too high to make a melt-out probable. i mean just calculate the energy to melt the now given amount of ice withing the remaining time and i believe that chances, even though never "zero" are as close to zero as one can assume.

after all the laws of physics remain in effect at all times, hence it's a very matter of fact amount of energy needed to melt the current ice volume.

There is all the energy you could possibly need just a few meters away from that ice.  The big known unknown is just how many meters.

I say that at some point there is enough overturning that all the sea ice melts out rather quickly and the Arctic Ocean can no longer pin the air temperature to near 0c.  I don't know when it will happen, but when it does it will be sudden -- leaving behind bergy bits and maybe some stuff flushed from the land.

26
Arctic sea ice / Re: The 2017 melting season
« on: May 24, 2017, 07:30:47 PM »
The expectation of meltponding in high pressure conditions is repeated whenever such conditions are forecast. I have not seen a rationale behind that expectation, or much evidence that these predictions are reliable. No doubt there will be many more predictions like this in the coming weeks and at some point there will be meltponds, but I very often see the correlation which can once more be observed at Obuoy14: low pressure, clouds and raised temperatures. I attribute this to inflow of warm moist air, and believe more rigorous observations by scientists confirm this.
This has been posted so often I can't be bothered to dig out supporting information again, which will be ignored as usual by people who seem to prefer what their gut tells them.

My prediction for Obuoy14 is rising air pressure will bring clearer sky and lower temperature.
(which will not protect the arctic ocean from a most likely bad i.e. low ice melt season, by the way, before the usual opinionators start shouting at me)

I tend to agree.  I think an Ocean climate is more important than a mere bit of sun on the desert of ice.

Only time will tell.

27
I voted "No gap will increase mainly for reasons other than albedo", but albedo is important. Specially over land. I think the gap will increase because the remaining ice will be easy to melt, warm air will keep flowing in and I think there is huge potential for export through the garlic press.

About the only thing I might add to that is that the broken ice is subject to wave action.  (And at some point will become subject to upper ocean mixing -- though I don't know when.)

28
Arctic sea ice / Re: Stupid Questions :o
« on: May 19, 2017, 08:11:09 PM »
coulee?


Having grown up in Washington State on the other side of the mountains from Grand Coulee Dam, this seems right to me.  The Coulees run along the Columbia from just about at the dam to about Mount Hood.

http://www.sevenwondersofwashingtonstate.com/the-channeled-scablands.html

29
Arctic sea ice / Re: Stupid Questions :o
« on: May 16, 2017, 05:18:11 PM »
since the oceans are warming in general, that cold spot, i relation to the surrounding seas, will ultimately still be warmer or the same like before. hope it's clear what i'm heading at.

a 2C colder spot in 10C water is 8C while while once it was 6 or 8 C for example. further i do not believe in those scencarios at all. even if the gulf stream will start dropping to the sea-floor 1000km earlier, it will still do it's job for most of western europe, perhaps, due to the generally warmer waters flowing up from the carribian even more so.

however, this is all prone to a huge amount of speculation due to its complexity, it's weven possible that the very very cold (1-2C waters flowing down from greenland will once simply free fall to the see floor, at least if the difference in temperature is great enough to compensate for the difference in salinity, or, it will first start to reduce salinity and drop to the sea-floor once salinity reaches a level where the difference in temperature has the great impact. last but not least we could face a different behaviour in winter and in summer, simply too many unknowns to make a bold statement like "IT WILL" IMO
We can speculate, or we can note that the Western Boundary Current (Gulf Stream) has trended poleward and sped up over the last couple of decades.

Whatever theory the idea of the currents slowing down and stopping is based upon, exactly the opposite has happened so far.

30
Arctic sea ice / Re: The 2017 melting season
« on: May 15, 2017, 11:41:27 PM »
I noticed that too. I wonder if there is a real physical phenomena behind this or is it an artifact of the measure.
Because it coicides with spring time and a weather pattern that tends to force cold wind across the Arctic Basin toward the Fram and Svalbard? It is not a exact science, but there might be a correlation. If the weather pattern is more frequent lately than in the past century...
Last year it did not cross but it was close.
Later in July August expect again negative anomaly esp this year with so much FYI... I bet! At least while we dont end up with a blue Arctic

In Spring the weather changes.  This happens every year with the same unstable systemic behavior we are seeing globally as the temperatures rise.  When it starts to warm up the weather becomes unstable and unpredictable -- both every year and every climatic warm spell.

Basically, we are seeking a new attractor...whether by the year or by the eon.

31
Arctic sea ice / Re: The 2017 melting season
« on: May 13, 2017, 12:45:19 AM »
I've only seen a spring river breakup once, but I remember it as both fast and dramatic.  Is it ok for me to consider the Nares Strait a river?

32
Arctic sea ice / Re: 2017 sea ice area and extent data
« on: May 13, 2017, 12:14:18 AM »

So is it that the outlying areas (which will melt out) are holding on, maybe due to the "wacky" weather whereas the key, core area is already declining ?

Isn't that what I am seeing in the Nares?

Weather isn't that wacky...the cold that used to stay at the pole has to dissipate somewhere.

33
Arctic sea ice / Re: The 2017 melting season
« on: May 12, 2017, 09:57:05 PM »
The Atmosphere is the weather.  The Ocean is the climate.  It's too early to tell, but I think this is the year we actually see climate change as weather.  The collapse of Nares was kinda a BIG HINT.

WACC is in our future, but I think Cold Continent is only in comparison, and not some sort of real cold.


34
I voted "No gap will increase mainly for reasons other than albedo," but I did that because I took the question as "albedo this season."  I think that albedo is the major ultimate cause after CO2 in making the Arctic warm faster that everywhere else, but I don't think it a main proximate cause.  Thus, I don't think open water early in the year is all that important in determining the volume late in the season.

35
Arctic sea ice / Re: The 2017 melting season
« on: May 11, 2017, 06:41:26 PM »
What is happening in the Arctic now?
Let's see if I can do a gif....

36
Please try to stay on topic. -- j.p.

<snip>

37
Consequences / Re: California weather extremes and climate
« on: May 06, 2017, 01:46:39 PM »
I am not advocating geoengineering though I sadly believe that it will be attempted in the next 15 years.

I have to agree.

38
Consequences / Re: California weather extremes and climate
« on: May 05, 2017, 11:44:40 PM »
we already know that aerosols cool the earth that is the basic science of it and the basic science alone is sufficient to promote an argument for geoengineering. 

I am not sure what you believe my aerosol argument is....
You just stated it in the preceding paragraph, and as I believe we screwed up 200 years ago I am not inclined to agree with screwing it up once again.

I just don't believe we know what we are doing.  Therefore I am not inclined to agree with any sort of geoengineering "quick fix."


39
Consequences / Re: California weather extremes and climate
« on: May 05, 2017, 06:38:37 PM »
My favorite chart, End-April volume, not even remarkable. A simple continuation of what looks like a linear trend, past a "plateau" that may have been random variability in hindsight.

This is good, however, it must also be suggested that the 2013 & 2014 'recovery' years were black swan events and are pushing the trend anomalously higher (straighter).  If these years effects did not occur and the volume gain during those years was removed then the trend would fall well below the long-term linear trend.

I believe for several reasons that these years events were a statistical outlier over 4 sig.

"Black Swan" seems a bit too extreme.  The paleontological evidence seems to indicate a bit of stuttering before the actual climate switch.  This is also consistent with how natural systems generally tend to undergo a change of state in General Systems Theory.  Most of the time the system tends to choke a few times before flipping to a new state.  If you think about it, that is what happens with things like computer networks which are in the process of crashing -- they stutter and then fail.

Jim

what you are saying is true to an extent, however we are not operating within a black box environment.  The 1976 and 2014 Gulf of Alaska blocking pattern has a distinct profile that is largely a result of varying upper troposphere aerosol loading.   I have been looking at this for a number of years now and the key indicator is that the Global Circulation Models (GCMs) used to model geoengineering (global dimming) show a strong and persistent blocking ridge in this region.

Therefore, while state-change activities are definitely happening, the drivers of specific systemic changes always have physical drivers.  It appears that the 2013/2014 cooler summers (and warmer winters in Alaska, drought in California and record snow levels on the east coast) are driven by regional shifts in high-temp process emissions of  aerosols (as happened in 1975 when Europe rapidly reduced their emissions but U.S. and Asia emissions were continued).

The 2013 event was similarly produced by reductions in U.S. emissions post 2007 crash but shifting this manufacturing to China who engaged in a command economy overproduction surge in 2013.

Without this knowledge this could appear to be a strengthening of natural variability under a shifting climate regime, but this is a black box analysis of a black swan event. 

This video has excellent analysis from people who were not aware of this aerosol driver.

https://www.youtube.com/watch?v=on0QmcDFgrg

I've been working on trying to absorb your aerosols argument, and I am tending to bifurcate on the matter myself.  I climbed Mount St. Helens twice before it blew up.  I am not unaware of what Pinatubo did.  At the same time, your analysis can be misused to promote a geoengineering solution, and I see no evidence that we understand the system well enough to predict the results.

40
Arctic sea ice / Re: Latest PIOMAS update (May)
« on: May 05, 2017, 01:02:25 AM »
My favorite chart, End-April volume, not even remarkable. A simple continuation of what looks like a linear trend, past a "plateau" that may have been random variability in hindsight.

This is good, however, it must also be suggested that the 2013 & 2014 'recovery' years were black swan events and are pushing the trend anomalously higher (straighter).  If these years effects did not occur and the volume gain during those years was removed then the trend would fall well below the long-term linear trend.

I believe for several reasons that these years events were a statistical outlier over 4 sig.

"Black Swan" seems a bit too extreme.  The paleontological evidence seems to indicate a bit of stuttering before the actual climate switch.  This is also consistent with how natural systems generally tend to undergo a change of state in General Systems Theory.  Most of the time the system tends to choke a few times before flipping to a new state.  If you think about it, that is what happens with things like computer networks which are in the process of crashing -- they stutter and then fail.

41
Arctic sea ice / Re: Latest PIOMAS update (May)
« on: May 04, 2017, 10:54:06 PM »
Total freeze:

This is probably the most important statistic Neven.  Can you give us a comparison with the 20th Century?

42
Arctic sea ice / Re: Latest PIOMAS update (May)
« on: May 03, 2017, 10:00:36 PM »
Uh-oh:





I'll post the rest later, but wanted to get these two up now...


I can see why...your projection from here for various years sort of says it all.

43
Arctic sea ice / Re: Latest PIOMAS update (May)
« on: May 03, 2017, 05:01:00 PM »
Another tiny piece of detail, the growth from End-March to Apr 25th was ~0.32 km3, more or less the average of the last few years. The negative feedback of low volume leading to higher growth failed to materialize.

Yes, according to the model.  The physical reality 'feels' like it should yield a higher growth.  Any ideas on what would drive PIOMAS lower than expected?

The Atlantic Ocean.

44
Arctic sea ice / Re: Latest PIOMAS update (April)
« on: April 30, 2017, 07:28:23 PM »
It should be expected that sea ice extent will continue to lag behind volume until some critical threshold of volume is reached and then SIE will collapse quite suddenly (I expect this to occur sometime around 750 km^3).

Can you explain your rationale behind the 750 km^3 figure?   I fully expect the regime to change when there is no longer enough ice to keep the ocean cold, but I have not so far found a good metric for when this will happen.

45
Arctic sea ice / Re: The Fast Transition
« on: April 29, 2017, 12:27:34 AM »
The snow discussion is getting off-topic.
I have to disagree in that an increase in snowfall seems to be one of the main characteristics of previous sudden warmings.  I might also add that there has been a marked increase in snowfall with the last winter.

Of course, winter snowfall is a marker, not the event.

46
Arctic sea ice / Re: The Fast Transition
« on: April 28, 2017, 09:13:49 PM »
I still believe we will soon hit a tipping point where the ocean is warm/ice-free enough to really rev up fall/winter snowfall numbers, enough so that we see snowpack begin enduring more and more readily into spring and early summer. We are already seeing this manifest in the anomalously high snow-volume numbers seen this year. How much more snowcover needs to build in fall/winter for extent to follow suit in the spring? I do not think we need that much more for this to begin occurring, though I could obviously be wrong (and the general consensus among most posters here is that I am wrong, so there's that too).

Nevertheless, the relationship between NHEM snow volume and arctic sea ice volume seems to have an inverse correlation, and as we continue seeing new lows throughout the year, it will be very interesting to see whether this relationship strengthens or weakens -- my bet is on the former.
If we had not been so overloading the atmosphere with C02 I think you'd be right, but as it is I think the snowpack will be a fleeting phenomenon.  I might buy into a short transition where the snow lasts as long as it did before....but not a state where the snowpack has any meaningful impact on overall climate.


47
Arctic sea ice / Re: The Fast Transition
« on: April 28, 2017, 08:25:44 PM »
bbr2314 - your second graph would seem to support a "more snow area in the winter but melts faster in the spring" hypothesis. Will be interesting to see what happens to snow extent in the next few weeks.

If there is greater snow cover on Northern Hemisphere land in Fall/Winter that should tend to reduce temperatures (although insulating the ground beneath). With increased cloudiness over the open Arctic Ocean in the darkness of Fall/Winter, it will tend to stay warmer. The overall effect may be to reduce the temperature differential between the Arctic and the rest of the Northern Hemisphere further?

That would be Warm Ocean Cold Continents (WOCC).  The best evidence we have on the past tends to support this as a regime.  One where the Arctic becomes a mist shrouded maritime climate and (at least at first) the continents become seasonally heavily snow covered holders of the remaining cold.

That may, or may not, give way to an equable climate.


48
Arctic sea ice / Re: The Fast Transition
« on: April 28, 2017, 02:20:38 PM »
I can only respond that the ice cores tell us there are sudden and complete changes in the climatic regime.  These seem to be in years or less, not centuries.


I suspect you're referring to events like the Younger Dryas and the various Bond events? The consensus is that these are all caused by freshwater pulses in the north atlantic (indeed they're not global phenomena) caused by large lake releases. In theory this could be replicated by rapid total ice melt, but Lake Agassiz was around 22,000 km3 in volume which is ~4 times the current summer minimum ice volume so it's hard to see it having the same sort of effect. Indeed, the seasonal arctic ice volume variation is around 20,000 km3 and, coincidentally, the annual loss from the Greenland ice cap is about the same again, which suggests that the ocean is absorbing 40k km3 of fresh water annually anyway (plus whatever drains from siberia). So you would likely have to have a marked increase in Greenland melting to trigger climate changing amounts of freshwater release.

I've never worked it completely through before but those figures do kind of suggest that even should all the summer ice melt out there wouldn't be a dramatic effect on the global climate (at least not from from freshwater pulses) and we should be more worried about the surface mass balance of the Greenland cap.


I think you are referring to the beginning of the Younger Dryas, not the end of the Younger Dryas.

http://www.pnas.org/content/97/4/1331.full

The Greenland records show that climate changes have been very large, rapid, and widespread. Coolings were achieved in a series of steep ramps or steps and warmings in single steps. The more dramatic of the warmings have involved ≈8°C warming (8, 25) and ≈2× increases in snow accumulation (9), several-fold or larger drops in wind-blown materials (17), and ≈50% increase in methane, indicating large changes in global wetland area (5, 24).

For the best-characterized warming, the end of the Younger Dryas cold interval ≈11,500 years ago, the transition in many ice-core variables was achieved in three steps, each spanning ≈5 years and in total covering ≈40 years (26). However, most of the change occurred in the middle of these steps. The warming as recorded in gas isotopes occurred in decades or less ( 8 ). The most direct interpretation of the accumulation-rate record is that snowfall doubled over 3 years and nearly doubled in 1 year (9). Several records show enhanced variability near this and other transitions, including “flickering” behavior in which climate variables bounced between their “cold” level and their “warm” level before settling in one of them (27).


49
Arctic sea ice / Re: The Fast Transition
« on: April 27, 2017, 11:26:14 PM »
Will a "Blue Ocean" event in September trigger positive feedbacks that will rapidly (e.g. a decade or so) lead to a seasonally ice free Arctic with blue ocean being the predominant state throughout the summer months?
These feedbacks would include:
- Albedo Effects (possibly mitigated by cloud effects)
- Reduced separation between the Arctic and Northern Hemisphere climate regions, allowing for greater amounts of heat transfer into the Arctic
- Greater level of storms and waves driven by open ocean (and heat contrast between ocean and land)
- Mixing of the water column in the absence of a thick ice cover, bringing up deeper, warmer water to the surface

With the extra heat taken into the open waters during Spring/Summer being vented into the atmosphere in the Fall/Winter months, will the freezing season be significantly reduced (i.e. less and less FDD's) - reducing the ability of the ice to reform and thicken?

Could the Arctic then transition to near ice free year round as the increased energy taken in through the spring/summer, together with greater heat transport from the south, reduces the FDD's further and further?
- Thinner ice at the start of the melt season leads to greater warming from reduced albedo, leads to less FDD's, leads to yet thinner ice the next melt season.

I can only respond that the ice cores tell us there are sudden and complete changes in the climatic regime.  These seem to be in years or less, not centuries.

I will go with the ice cores rather than the models.

50
I have just been catching up with this forum. Someone mentioned that anyone putting a vote for 2090+ is a denialist. I am anything but. In fact I see predominately  ice free conditions by September starting no later then 2030 and would not be surprised to see it before 2020. The point I made and I bbelieve there are others who voted for 2090+ see the same thing, is if the weather hit perfectly, you could end up with ice extent over 1M km2 in any single year. To deny that possibility means you are looking at Arctic temps by mid summer getting no lower then 5C in any particular year, which even the most extreme forecasts do not call for.

That is very logical, however, even the most extreme forecasts do not agree with the paleontological evidence.  The evidence is for sudden and generally rather extreme change.

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