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Messages - Glen Koehler

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1
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: December 07, 2019, 08:20:12 PM »
The 2019-20 Freezing season is about half-done in elapsed days, and about 2/3rds done in extent gains. During the freezing season, AREA is a lagging indicator, so here are EXTENT graphs looking at the whole freezing season - September to March

CANADIAN SEAS
Baffin Bay
A surprise this year - early to melt, late to freeze. Will the maximum also be a record low?
Of interest (at least to me) is that over the years the March sea ice maximum is declining much faster than the September minimum (which still does not reach zero). This is in contrast to the overall trend in the Arctic Seas. The Atlantic warmth is pushing north?

Canadian Archipelago (CAA) Is frozen completely pretty much on schedule, or maybe 5 days late?

Chukchi Sea Freezing is late, very late, but looks like the only question is how late the complete freeze-up will be.

Hudson Bay Freeze started late but is now playing catch-up with a vengeance. But will final freeze be early, on time or late?
[/quote]

2
Arctic sea ice / Re: "Stupid" Questions :o
« on: December 07, 2019, 02:22:39 PM »
Binntho, there will be no convincing you until events convince you, which IMO they will. But have you at least read or heard Bobby Kennedy's iconic GDP speech from 1968? GDP is now widely recognized as a deeply flawed measure that fails to capture much of what human beings actually value in life.  It's well worth a read. Here's an excerpt:

But even if we act to erase material poverty, there is another greater task, it is to confront the poverty of satisfaction - purpose and dignity - that afflicts us all.  Too much and for too long, we seemed to have surrendered personal excellence and community values in the mere accumulation of material things.  Our Gross National Product, now, is over $800 billion dollars a year, but that Gross National Product - if we judge the United States of America by that - that Gross National Product counts air pollution and cigarette advertising, and ambulances to clear our highways of carnage.  It counts special locks for our doors and the jails for the people who break them.  It counts the destruction of the redwood and the loss of our natural wonder in chaotic sprawl.  It counts napalm and counts nuclear warheads and armored cars for the police to fight the riots in our cities.  It counts Whitman's rifle and Speck's knife, and the television programs which glorify violence in order to sell toys to our children.  Yet the gross national product does not allow for the health of our children, the quality of their education or the joy of their play.  It does not include the beauty of our poetry or the strength of our marriages, the intelligence of our public debate or the integrity of our public officials.  It measures neither our wit nor our courage, neither our wisdom nor our learning, neither our compassion nor our devotion to our country, it measures everything in short, except that which makes life worthwhile.  And it can tell us everything about America except why we are proud that we are Americans.

https://www.jfklibrary.org/learn/about-jfk/the-kennedy-family/robert-f-kennedy/robert-f-kennedy-speeches/remarks-at-the-university-of-kansas-march-18-1968

3
Arctic sea ice / Re: "Stupid" Questions :o
« on: December 07, 2019, 07:50:56 AM »
Well said Glen.

And binntho - usually I would jump back in, but I will sit this one out. As you seem to truly believe the stuff you wrote, arguments will be pointless.

4
Arctic sea ice / Re: "Stupid" Questions :o
« on: December 06, 2019, 06:33:33 PM »
I'm not sure if it would make any difference. And GDP is a truly narrow measure, far from being the best. But it's the only one. Health, happiness and environmental protection follow GDP - the higher the better. Total consumption also follows GDP which is a definite downside.

Our only objective should always be the maximum happiness for the most people. Biodiversity and sea level must take second place to maintaining and protecting food production.

In an ideal world we would have started a massive drive to avoid AGW some decades ago by using government funding to jumpstart a shift in energy production away from fossil fuels. But any such plans were doomed from the start, I think, and are not very likely to be adopted in future. We might stumble into a sharp reduction in CO2 emissions simply through the increasingly favourable economics of renewables, but there will be an absolute minimum of conscious common effort to do so. Unfortunately. But not an existential threat to civilisation.

I don't know where to start...simply remarkable.

BAU will deliver a 4C warmer world by the end of the century at a minimum. This global temperature is absolutely incompatible with human civilization. Will we drive ourselves to extinction? No. Will those of us who are alive wish they were dead? Perhaps.

5
Arctic sea ice / Re: Latest PIOMAS update (December 2019 )
« on: December 04, 2019, 04:08:04 PM »
You always know that a linear fit is not good when the first half of the data are (mostly) above the trendline and the second half is (mostly) below it.
I suggest that there was not much trend on your chart until the beginning of the 90s, then you had a steep downtrend till cca 2010 and now you have a less steep downtrend since then
Don't matter - the only trend is down.

I posted a load of stuff on "when will the Arctic go Ice-Free" about outliers. Using the standard methodology (sort-of) I isolated the outliers for extent and volume and the linear regression fit much better. First 3 attachments (September volume only).

I also looked at trends in area, volume & thickness for September using unadjusted data. Attachment 4.

The only trend is down.

6
Arctic sea ice / Re: Latest PIOMAS update (June 2019)
« on: December 04, 2019, 01:03:40 PM »
Yet again, this person does "have use for the updated regional data files" from Wipneus:

PIOMAS Volume as at 30 November 2019  10.349 km3 '000
The standard graphs and tables as I use for the JAXA extent data are attached.

Volume gain in 1st week of November well above average.
Volume gain in 2nd week of November well below average.
Volume gain in last 2 weeks of November well above average declining to average by end of the month..

2019 volume is still 3rd lowest in the satellite record, by 211 km3 above 2012, and 965 km3 above 2016, and less than 2018 by 1,104 km3.
_______________________________________________________________
The last table is a look at projections to the next maximum. Far too early to take it seriously.

7
Arctic sea ice / Re: "Stupid" Questions :o
« on: December 04, 2019, 11:54:32 AM »
Binntho, in my humble opinion, you are more than average intelligent person. You have the ability to succeed in the world of ideas. But you look like Icarus.
Sidd is totally right. We are living because some 10% of our body mass are bacterias and other alien microorganisms that live in symbiosis with our body. Gaia can stay in homeostasis because of all life interacting in her guts.
Maybe one solution could be that all the tech-believers join Elon and fly to Mars so they can fiddle their environment, their GDP, their abstract ideas and with no 'nature' inconvenience, colonize again a planet till it's all overcrowded and spoilt, and then jump to another one. Good luck!
The rest of us, not regretting tech, but not idolising it, could try to live calmly controlling our numbers and not controlling the rest of Gaia. (Although I think this would need some evolution in the H. Sap.)

9
Arctic sea ice / Re: "Stupid" Questions :o
« on: December 04, 2019, 08:51:56 AM »
So we are back with the more mundane things that are easier to predict. Say the chances of a 6m rise in sea levels before 2100. If it were to happen, major disruptions to low-lying areas will cost money, major construction projects to meet the threat will cost money, moving of cities will cost money. But the impact on the global economy? Might even be significantly positive, major construction efforts, building of newer and greener cities, etc etc. Money can be produced at will by governments to meet any need, and pumping it into the economy to pay for major construction work will have a positive effect on economic growth.
Binntho I am beyond amazed by this. 6m sea level rise could be good for the economy? The USA can't even maintain its own current infrastructure, and you expect that with several major cities under the waves (NYC, Miami, Boston, DC, NOLA, parts of LA, Houston, and many more) spewing pollution into the ocean, all ports underwater, many airports underwater, coastal power plants underwater, this will be good for the economy because money printing will fix this? It's an issue of resources, not money. And globally? London, Shanghai, Karachi, Alexandria, the whole of Bangladesh, the list is endless I can't even be bothered to google it. All highly productive river deltas underwater. And this in the span of 8 decades, good luck to humanity. Not to mention the climate changing and environmental destruction - the above is just SLR. And supposedly 10 billion humans on the planet.
Luckily, 6m probably won't happen so soon but 2-3m by 2100 will still cause lots and lots of physical damage.
This whole discussion is OT in this thread, if you care to repost in a proper thread I might bother with a longer answer, but seriously please reconsider.

10
Arctic sea ice / Re: "Stupid" Questions :o
« on: December 04, 2019, 08:04:44 AM »
Re: the impact on the global economy

what of the impact on the ecology ? Let us say that through great effort we actually ensure that there is no impact on the economy.

But there are no insects or worms or beetles or birds or fish or wild animals left  outside zoos and the entire earth is groomed to human need with robots performing ecosystem services.

I am sure some here would be cool with that.

But in larger sense it is not up to us. We will die, and our children will live with what we leave, and their choices will be circumscribed by limits we construct. So mebbe ask them ? I do, and the answers are interesting. I recommend that experiment.

sidd

11
Arctic sea ice / Re: What's new in the Arctic ?
« on: December 04, 2019, 03:09:44 AM »
In reality Point Hope is wholly on the Chukchi Sea coast.

Point Barrow (Utqiagvik) is the official border between the  Chukchi and the Beaufort Sea.
Wrangel Island is the border between the Chukchi and the East Siberian Sea.
And of course the Bering Strait is the border between the Chukchi and the Bering Sea.
The Barrow-Wrangel line, or somewhere north of it, is the less-defined border to the Arctic Ocean.


12
Arctic sea ice / Re: "Stupid" Questions :o
« on: December 04, 2019, 02:48:54 AM »
Here is their latest argument. I have to admit, it is the best they have come up with yet:
Quote
Okay, Tom, what do we do? How are you going to live with zero carbon emissions? Forget windmills and solar, they take mining, which is also a no-go. Forget hydro, that also requires mining and destroys the environment where the dams are built. So, we've got no real means of energy production. Since animals apparently also cause CC, we shant be using them. You going to go out and harvest crops with your bare hands? You going to live without cars, electricity or anything this side of wooden or stone huts?
Tell me, please, how we're going to live?
Anyone who has actually gotten past the "The guvmint must do something!!111!" has pie-in-the-sky ideals, but trying to actually implement them results in a bigger mess than we're now in. So, what are your plans? Lay 'em out.

They also say that any AGWphobe who does not support nuclear is a hypocrite. Well, I am not a hypocrite, I support nuclear in the mid-term (in the long term we will need renewable or fusion...uranium is too rare).
They are trolling you very nicely Tom, really by the book. All of these arguments are rehashed, nothing original.
Somehow when it comes to replacing fossil fuels, all these die-hard deniers suddenly become environmentalists. Mining is a no go. Right. But fracking for oil and gas while poisoning the water and causing earthquakes, just to burn it and cause AGW, is perfectly fine by them. Forget hydro. Right. It destroys the local environment. Are these the same folks that said who cares about 2100? You think you are having a fruitful discussion, while they are having a field day.


The truth is, should the US and other countries decide/realize that AGW is the same as World War III, the whole energy system could be transformed in about a decade, max two decades. The solutions are well known - solar plants and rooftop solar, wind turbines (not windmills, this term identifies deniers), grid batteries, in addition to hydro and geothermal and existing nuclear until it is retired. And yes, some natural gas backup. Maybe for a few years people will have to do with a reduced amount of barbie dolls and flights to exotic locations, but that is nothing compared to the suffering that will come by not acting. Read some history, about the wartime economies of the UK and the US during WWII. When people realize the house is burning down and that the enemy is at the gates, they are capable of moving fast and temporarily giving up some of life's enjoyments - for the cause.

The truth is also, that all human activity causes some damage to the environment, and the truth is also that 7.6 going on 10 billion humans is well above the carrying capacity of the planet. So no plan will be perfectly clean and no plan will get you past the crisis point harmlessly. To fix that, big steps were needed fifty years ago (but thanks to trolls like that, these steps were not taken).

But the truth is, renewable energy is much cleaner and much less harmful than the current alternative of coal, oil and gas. And EVs are much cleaner than ICE vehicles. So energy and transportation can be transformed with the means we have on hand right now. And there are ways (more difficult, less comprehensive) of transforming other carbon sectors - construction, industry, plant and animal agriculture. It is impossible to maintain current lavish lifestyles, not to mention provision of these lifestyles globally, while achieving carbon neutrality in short order. But it is possible to achieve a 50% reduction relatively quickly. And afforestation can do a lot as well. Some savings will come by eliminating the huge fossil fuel sector itself - prospecting, drilling, mining, transporting, refining, distributing. And good riddance.

So the truth is, the situation we are in is a much bigger mess than the situation where parts of the economy are transformed towards carbon neutrality, even if that is not a full solution for humanity's problems.

13
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: December 03, 2019, 09:26:42 AM »
Has anyone proposed a mechanism for the sudden acceleration then return to prior trend ?

As far as I know, nobody has come up with a good explanation for the big dip, nor for the slippery slope. Which perhaps tells us how little we know about what's going on up there!

Binntho,

I haven’t marshaled the plots and data to show it, so take this as my guesstimate as to cause rather than as a rigorous argument.

I think several factors are involved.

First, extent as it is defined is a crude tool ill suited to assessing the ice condition as we enter the terminal phase of the meltout of the Arctic Ocean. It’s original intent was to smooth the edge measures of the melting sheet. The difference in using a wide array of assumptions about the area of ice in a measured surface area to count as 100% ice wasn’t particularly impactful or important. Now that the central arctic is breaking up each year that no longer holds true.

Second, beginning about 2004 the annual melting of the arctic ice began to seriously involve the central arctic. By 2007 it was basin wide.

Third, as the melt has progressed, the sheet has progressively thinned. This exposes more and more ice area to breakup into smaller chunks with more ocean between them.

Fourth, fifth, sixth, seventh ... the mixing of the near ice sea under the ice became greater exposing the ice to warmer more saline waters; the fluxes of fresh water driving the great oceanic current began to collapse which greatly shifted the oceanic movements; the atmosphere began to destabilize introducing several new wrinkles into the ice dynamics; masking effects of ponding declined as the unit areas of intact ice segments became smaller  ...

I suspect that several key factors came into play. The ice area (not extent) became more volatile annually as the initial area subject to melt declined, and with it the annual minimum areas. This exposed the ice to greater variability in ice area subject to all of the melt processes. That then allowed a shattering of the sheet. It is/was almost inevitable that at some point the 15% ice cover definition for extent would be breached over large areas of shattered ice sheet. This would give the false impression of a sudden decline in extent, not matched by a sudden decline in area. In truth what it reveals is the inadequacy of extent being used as a surrogate for ice condition.

Ice area suffers a similar flaw. The ice has thickness. When the ice thickness falls below a critical threshold, the ice area may likewise suffer great variation and sudden drops. We seem to be seeing the first of these in the past decade. I wonder how much longer we have until the second shows up.

I suspect that we shall soon have answers to those questions. And that when we do that they will be meaningless, as the September minimum will have seemingly suddenly reached near zero.

Sam

14
Arctic sea ice / Re: "Stupid" Questions :o
« on: November 25, 2019, 12:00:17 AM »
Quote
1. Not doing a cost/benefit analysts is insane and of low morality, and

What about a cost-benefit analysis that underestimates the cost of not doing anything and overestimate the cost of doing something? What is the morality of such an analysis?

Quote
2. We don't want to promote a cure that is worse than the disease, and

The disease if left untreated is fatal. The cure, if done right leads to a better quality of life for everyone.

Quote
3. Doing the cost-benefit analysis is the sane way of preventing 2 above.

You are right about this. The current Nobel prize-winning cost-benefit analysis is insane, that's why it is not working.

15
Arctic sea ice / Re: "Stupid" Questions :o
« on: November 24, 2019, 04:47:20 PM »
Thanks for the response.

"must be weighed against the benefits"

Shall we ask the children this question of cost and benefits.
And, how expensive is the survival of civilisation and most of other lifeforms?

To me these costs/benefits questions/policies of yes/no taking action are insane and very low morality.

16
Arctic sea ice / Re: "Stupid" Questions :o
« on: November 24, 2019, 10:55:43 AM »

I am not confused, I am convinced taking action is the appropriate strategy. But I am saying we should consider what it looks like to people who are not convinced.


I understand, but why are they not convinced of the possible dangers?  My belief is that it has nothing to do with available information or logic. The information is there and it is extremely clear with just basic inspection. The people who are resisting action are not acting on logic, we must ignore them or kick them to the curve if they get in the way. No need to change the message to fit their delicate sensitivities, only speak the best truth possible. They will not change their minds because the implication of climate change is terrifying and life-altering.

We have already tried the "climate change is a problem for 2100" trick. That was the real lie. The concept was logical. If we lie to the people and tell them this is a problem for 2100 and our children, then maybe, just maybe, we will appeal to their common sense, without scaring them too much. Surely action will be taken. It failed. Miserably. CO2 is climbing fast.

I suggest we state the truth as best we know it and do not try to hide or reduce the possible threat for fear of being made fun off.

I agree that exaggeration is not good, but when talking about the unknown future it is very difficult to know when one is exaggerating. That humanity is at risk of collapse due to climate change is most certainly not an exaggeration. The exact way is too complex to know.

17
Arctic sea ice / Re: "Stupid" Questions :o
« on: November 23, 2019, 03:47:16 PM »
How far in advance can we foresee a big El Nino coming?

One can predict an El Nino by looking at ocean and atmosphere temperatures in the Pacific in the year leading up to it. For example, according to the US government climate.gov/enso this year will probably be neither El Nino nor La Nina because the water is warm but the air is cold.

However, one cannot easily predict the strength of an El Nino, as it's very much a weather event and predicting the weather is a nightmare.

There is a May/spring barrier to prediction. From June/July you may be able to have reasonable prediction for up to 9 months to a year ahead. However if you cross May barrier, you shouldn't trust it as much. So more like 6 months at this time of year. This barrier is not absolute: there is some skill in prediction across May barrier, just not as much as at other times of year.

this is as far as I understand, don't ask me why.

18
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: November 20, 2019, 07:37:20 AM »
 
I get that you feel strongly that there is nothing unique about the ice in the basin that tends to remain at the minimum nor is there any reason to suggest that the ice that tends to exist at the minimum is any more difficult to melt than ice in the peripheral seas.

I do have strong feeling, but not on this subject. What tends to raise my hackles is the tendency too often seen (and so very human) to see patterns in everything, to over-interpret correlations without any notion of causation, to make spurious claims without proper foundation and then maintaining and repeating those claims even when they are shown to be dubious or even plain wrong.

There are many recent examples: The supposed stall, the supposedly "easy" and "difficult" to melt ice types, the supposed effect of bathymetry. All of these "supposeds" stem from our hyperactive pattern-matching abilities. We humans are simply incredibly good at seeing and finding patterns and apparent correlations. But what is lacking is the causality. What are the mechanisms behind these supposed patterns? If you cannot explain the causality, then most likely the pattern only exists in your mind.

Which is not to say that the causality isn't there! Perhaps there was a stall, but then why? Glen Koehler has done a fantastic job of finding real evidence for the fact that ice melts the same everywhere. So any causality behind a stall seems to be very unlikely.

As for bathymetry, I have seen no research that points either way. I do remember some very significant contributers to this forum (people putting in real scientific work) pointing to the apparent correlation between the edges of the continental shelves and the summer mininum. But so far nobody has been able to point to the causality, the mechanism involved. The Laptev bite may be caused by bathymetry, but precisely how? I've not seen any attempts at explaining the underlying mechanism.

So that's why I keep on needling those who think that once you see a correlation, you have discovered a law of nature. It's simply not so.

19
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: November 19, 2019, 10:07:49 AM »
Actually the Atlantic side correlation is probably due to physical reasons, as has already been discussed here upthread. Heavy Atlantic water sinking below light Arctic water at the point where the bathymetry allows, unless Arctic water has been heavily mixed and even then it just moves the front rather than eliminate it.
Elsewhere it's probably as you say - the CAB, where September ice is mostly found, happens to be over deep water, so a general correlation is to be expected.  However deep water does not explain the shape of mid-September ice, as uniquorn's animation clearly shows, so no causation.

20
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: November 18, 2019, 09:45:26 PM »
A reminder of minimums and bathy since 2012. I would say there is some correlation on the atlantic side.

21
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: November 18, 2019, 08:36:40 PM »
lacking a plausible mechanism in no way minimizes the deductions from the data.  We cannot ignore the data, just because we do not understand why.

C'mon, you'd be the first to jump on the "correlation does not imply causation" bandwagon if the data were saying something different.

22
Arctic sea ice / Re: Global sea ice area and extent data
« on: November 15, 2019, 08:24:55 PM »
I compared the actual JAXA extent data with the averages from 1980s to 2010s.
Arctic sea ice extent of 2019 is 4 days behind schedule if compared with the 2010s average. In the Antarctic 2019 is ahead by 7 days, which sums up to 11 days of difference.
These differences are bigger in comparison with earlier decades:
2019 vs 2000s: 15 days Arctic, 8 days Antarctic = 23 days
2019 vs 1990s: 25 days Arctic, 8 days Antarctic = 33 days
2019 vs 1980s: 29 days Arctic, 9 days Antarctic = 38 days
This is a difference of more than a month!

23
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: November 15, 2019, 02:29:38 PM »
Arctic Ocean May Be Ice-Free for Part of the Year As Soon As 2044
https://phys.org/news/2019-11-arctic-ocean-ice-free-year.html



... For their study, Thackeray and co-author Alex Hall, a UCLA professor of atmospheric and oceanic sciences, set out to determine which models are most realistic in how they weigh the effects of sea ice albedo feedback, which they figured would lead them to the most realistic projections for sea ice loss.

Thackeray and Hall assessed 23 models' depiction of seasonal ice melt between 1980 and 2015 and compared them with the satellite observations. They retained the six models that best captured the actual historical results and discarded the ones that had proven to be off base, enabling them to narrow the range of predictions for ice-free Septembers in the Arctic.



Chad W. Thackeray et al. An emergent constraint on future Arctic sea-ice albedo feedback, Nature Climate Change (2019)

24
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: November 15, 2019, 01:39:37 PM »
After looking at graphs of individual seas and making comments on them, this is the quote that seems valid, and  even more so, for many of the individual seas.

Changing state of Arctic sea ice across all seasons
Julienne Stroeve and  Dirk Notz

Quote
5. Accelerated sea ice loss during all months of the year is additionally driven by a lengthening of the melt season. As assessed for the Arctic as a whole through April 2018, melt onset is occurring 3 days earlier per decade, and freeze-up is happening 7 days later per decade (figure 3). Over the 40 year long satellite record, this amounts to a 12 day earlier melt onset and a 28 day later freeze-up.
[/size]

The summer melt turns from a V shape  into a U shape

25
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: November 12, 2019, 06:35:34 AM »
Well if binntho agrees with me, he must be right! 
I'm sure I am!   8)
Quote
   Edited quote
And we already know that volume is falling faster than extent, which means that thickness is falling faster than extent.
    I don't agree with the second part, "... which means that thickness is falling faster than extent. " 
    Yes, we know that volume is falling faster than Extent.  Because Volume is the product of Extent x Thickness, Volume has to fall faster unless there is either thickness gain or zero loss.  But thickness does not have to fall faster than Extent for Volume loss to be less than Extent loss.  It does not matter which is greater, or if they are exactly equal, all that matters is the product of Extent x Thickness, because that is what defines Volume.

Although I've had quite a few cups by now, coffee alone does not really help me out here - some sort of higher mathematics is needed. However, a bit of playing around with Excel shows that if both extent and volume are falling, and volume is falling faster than extent, then thickness is going to fall faster than extent.

That was also my gut feeling, i.e. that thickness had to decrease faster than extent if volume was decreasing faster than extent. But the difference is not necessarily very big. As an example, if extent is falling by 1% per year, and volume by 2%, then thickness falls by very close to, but ever so slightly above, 1%. If extent is at 1% and volume at 3%, thickness clocks in at slightly above 2%.

So until proven wrong by somebody better at mathematics than me, I'll state that if volume is falling faster than extent then thickness has by necessity to fall faster than extent - but not necessarily by a measurable amount! It all depends on the difference between the other two rates of decline.

26
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: November 12, 2019, 04:49:22 AM »
Global warming paused ....if you ignore ocean heat content.
Sea ice decline paused.... if you ignore volume.
 :D

27
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: November 12, 2019, 04:29:31 AM »
The ice cube video strongly supports all of Glen's excellent postings! Having started this discussion, and then buggered off to a part of the world with minimal Internet, I've still been able to read most of it and Glen seems to have effectively put the case to rest - linearity rules ... until it doesn't.

My gut feeling has long been that global warming is the main and domineering driver of sea ice melting, i.e. if the world keeps warming up then the ice should keep smelting - and since global warming has been as close to a straight line as makes no difference for the last 30 years, ice melt should also be as close to a straight line as makes no difference over the same period. Hence no hiatus when it comes to ice loss over the same period.

As for the future - as Glen has demonstrated so well, the science tells us that ice loss and the rate of warming (and at a further remove, the increase in cumulative atmospheric CO2) have a linear relationship well into the future. And by ice loss I of course mean loss of volume (i.e. actual loss, rather than the symptomatic loss of extent).

So loss of volume, from here and down to practically nothing, should follow global warming in a linear relationship, which of course means that extent has to catch up at some point. Which Glen has covered very nicely with his discussion of how thin ice can suddenly go poof, losing a million or more KM2 in a few days.

28
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: November 11, 2019, 11:43:41 PM »
I am not a scientist or expert. I love the charts and numbers and basically understand them.

I do have significant experience doing things in nature. And this has been said earlier but it bears repeating.... Nature abhors a straight line.
I tend to agree.

To me, area and extent are fun to watch, but it is giving too many nice straight lines until the ice disappears.

My bet is for the ice to disappear before 2025. And my reasoning might be far too simplistic, but this short video of ice melting explains why I think it will look basically okay in terms of area and extent right up until it isnt.


29
Arctic sea ice / Re: The 2019/2020 freezing season
« on: November 10, 2019, 07:34:11 AM »
I have spent many years lurking on this forum. Over the years I see little to give me hope that climate change will not devastate the Arctic and the planet as a whole.

I teach climate change in my classes at a community college in Southern California. In my feeble attempt to explain how these great dips of the jet stream that bring an Arctic blast to the eastern half of the USA can hurt the Arctic I use a freezer we have in the classroom. I open it up to let the cold out and ask them “When I close the door, how does the freezer make it cold again?” I tell them about condensers and heat exchangers.

 I ask them “How does the Arctic keep so cold when its freezer door is opening when the jet streams make these large dips?” My feeble answer is we have a season of dark in the Arctic that is the time when we generate all the cold in the Arctic freezer by a lack of energy input directly from the Sun. Without that energy,  some of the energy brought in during the season of light will radiate into the atmosphere and eventually into space and at some point reach a point where the energy levels have dropped enough to freeze water and form ice that seals any remaining heat energy in the waters below it. Once the waters are sealed off by the ice, energy in the air continues to loose heat energy into space and becomes ever colder. So as long as the period of dark is exporting/exchanging more heat than it imports during the season of light we will have a functioning Arctic Freezer.

When the Arctic experiences two things: 1) Importing more heat during the season of light than it had before, and 2) opening the Arctic Freezer door more often during the season of dark, the Arctic Freezer will become more and more strained until it is no longer capable of acting as a freezer.

Why I watch this forum is to try and understand the heat gain and heat loose in the Arctic.

30
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: November 09, 2019, 04:59:24 PM »
My 2 cents worth which, due to market demand, is only worth a penny.

Thinner ice is more fragmented, mobile, dispersed and saline IMHO. All of these would cause this ice to go poof faster than thicker ice.

31
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: November 08, 2019, 05:17:07 PM »
Gerontocrat, your graphs has gotten me thinking.  What if the open water in the peripheral seas is contributing to larger heat losses, resulting in faster refreeze of the CAB?  Widespread ice cover in the past may have kept more heat bottled up beneath the ice. 

32
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: November 08, 2019, 03:49:34 PM »
Thanks, Richard: I think you've referenced the 'science' I was looking for.  (I have functionally no thermodynamics formal education.)  Can you say more about the melting process?  About how and why the temperature gradient changes in ice as it melts? 

As I wrote these questions, I realized that for freezing sea ice, all the heat exchange is from the water, through the ice and into the air.  During the melting season, the heat exchange is from both the 'air' and from the water below.  In a colloquial sense, the 'cold' enters the ice only from above and leaves the ice in both directions.

33
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: November 08, 2019, 04:01:23 AM »
The latent heat doesn't get conducted through ice when it melts, but it does when it freezes.

Consequently thicker ice freezes slower, but it doesn't melt slower.


34
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: November 08, 2019, 12:03:56 AM »
Maybe there is none.

I think that just flipping the graph is not valid but could we think of the curve for melting. What would it look like?

Thinner ice is more effected by the sum melt (top and bottom) and at some point it breaks up and fractures which accelerates melt.

Then there is the factor of location (cold north) and the deep seas beneath and what that possibly does to the currents and we have to consider that a lot of ice that ends up in the central arctic seas was made somewhere else and that might fail so who knows what happens next.

We don´t know what the worst case effect of the weather could be with prolonged open weather mixing up the outer arctic seas or the precise effects of atlantification and pacification going forward.

There are simply to much variables to settle the question.
 
My first question would be at which thickness will melting ice break up. At some point it becomes   less rigid and waves will damage it more. That should be an important point.


35
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: November 06, 2019, 07:39:08 AM »
A BOE as specified by gerontocrat will happen because the whole system is changing towards an equable NH.
No it isn't.
For all, raging about an equable climate, I suggest reading this:

https://www.seas.harvard.edu/climate/eli/research/equable/climate.html

and all the other pages there. They have a nice collection which explains the science behind equable climate.

Shorthand: Nobody exactly knows why it happened, but there are competing theories, some more believable, some less. But you need much more warming than currently to get there

36
Arctic sea ice / Re: The 2019/2020 freezing season
« on: November 05, 2019, 03:17:56 PM »
How much Bering ice will form?

How weak and thin will the Chukchi ice be?

How much will this lack of buffer effect early melt?


I think this next year may see severe anomalies and its effects may penetrate into the central arctic.

Everything is very bad. The Pacific side continues to overheat, the Beaufort circle is pumped with heat.

Even with a neutral ENSO index, we have almost a record for ocean temperature:


37
Arctic sea ice / Re: The 2019/2020 freezing season
« on: November 05, 2019, 01:11:18 PM »
I’m wondering if the very quick refreeze is actually a bad thing? I remember several people here stating there was a lot of snow on the ice pack in May. Which delayed melting (melt ponds didn’t form). I know the snow can come from other areas but the quicker the refreeze of the Arctic Ocean the less moisture would be available for snow to fall in the arctic.

Does this make sense?

While there are arguments pro and con - "sealing in heat", less venting to space, less snow vs more humidity and warmth in the lower atmosphere, more insulating snow, etc. etc. I have to defer to Occam's Razor: more and earlier freezing is good for the ice; less and later freezing is bad. This is probably overly simplistic and there are likely countervailing samples here and there across the arctic, but overall, that's my guess.

38
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: November 03, 2019, 06:36:19 PM »
Record low sea-ice extent for October in the Arctic

Quote
October 2019 sets a new record low for October mean sea-ice extent in the Arctic, thereby joining April 2019 as new record holders from this year, and with the May to August all being second-lowest for their months.

Link >> https://cryo.met.no/en/node/274


39
Arctic sea ice / Re: The caa-greenland mega crack
« on: November 03, 2019, 03:08:41 PM »
uni-hamburg amsr2-uhh, north CAA/Greenland, 2012-2018 (some missing data)

40
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: November 02, 2019, 04:03:34 PM »
OPEN WATER GRAPHS  - updated with the 3 month minimum ice area data (August to October)

These graphs look at how much open water in the various seas of the Arctic.

Total Arctic Seas

The average for the year in the 1980's was just 40%. It is now creeping to above 50%.

For the three minimum ice months Aug-Oct the open water percentage has risen from 60-65% to 75-80%.

The early melting season (May-July) the open water percentage has risen from 40% to a bit over 50%.
__________________________________________________
High Arctic Seas (Central Arctic, CAA, Beaufort, Chukchi ESS, Laptev, Kara
i.e. excluding peripheral seas generally farther south and/or open ocean borders 


The average for the year in the 1980's was just 15%. It is now creeping up to around 25%.

For the three minimum ice months Aug-Oct the open water percentage has risen from 30-35% to 50-60%.

The early melting season (May-July) the open water percentage has risen from 10-15% to a bit circa 25%.
__________________________________________________
This overall average disguises large variations in individual seas. Over the next hours (days?) I will post graphs by individual seas.
_____________________________________________________________
Notes:-
I made these graphs to track the progress of the gradual transformation of the Arctic Seas from Ice Desert to Open Water environment. Looking at longer periods, e.g. 3 months, one can see, e.g. how the open water season is lengthening (August to October) and melt starting earlier (May to July).

Calculation
The data is shown is calculated from the average sea ice area for each period divided by:-
- the total area of the sea if totally enclosed by land or other seas (e.g. Central Arctic, Kara),
Or
- the maximum ice extent recorded since 1980 (e.g. Bering, Baffin, Barents, Greenland).

This gives the percentage of ice coverage. Open water is then 100% minus that percentage

41
Arctic sea ice / Re: "Stupid" Questions :o
« on: November 01, 2019, 02:31:10 PM »
Yes Kassy.  Additionally, extent and area show the largest divergence during the late summer and early autumn months, as larger ocean surfaces show enough ice to be considered ice-covered in the extent measurements, but are not fully ice covered for the area measurements.  Slush qualifies as ice-covered for extent measurements, but only partially in the area measurements.  During late winter, extent and area measurements converge as most of the surface is ice-covered.  NSIDC prefers using extent as the measurements have been more consistent over time (area measurements tend to fluctate more due to thin ice and melt ponds).

Volume is calculated using the Pan-Arctic Ice Ocean Modeling and Assimilation System (PIOMAS).  The model incorporates sea ice thickness, calculated using the HYCOM-CICE model developed by DMI and sea ice concentration (different from extent or area).  Consequently, volume can differ significantly from either area or extent. 

42
Arctic sea ice / Re: 2019 sea ice area and extent data
« on: October 30, 2019, 08:06:16 AM »
I attach three tables which show the number of days sea ice extent has been below 5M, 6M and 7M km2 around the minimum in a year.
  • 2019 extent was < 5M km2 for 64 days, which is the second highest amount, just 1 day behind 2012.
  • 2019 extent was < 6M km2 for 86 days, which beats the old record of 77 days set by 2007 & 2012 by a big margin.
  • 2019 extent was < 7M km2 for 100 days, which is the tied record together with 2016.

43
Arctic sea ice / Re: The 2019/2020 freezing season
« on: October 27, 2019, 08:47:41 AM »
A Polar Vortex Split is coming in about a week.
This is again, very bad news, coming earlier Year by Year.
The Oceans are just spewing out Heat, relentlessly.

Why is the release of heat a bad thing since it can now radiate back into outer space? I am confused when the complaint is that heat is being trapped in the ocean and also when heat is not being trapped. I just want consistency.

44
Arctic sea ice / Re: The 2019/2020 freezing season
« on: October 26, 2019, 03:15:40 AM »
Exactly the area around the Greenland crack as talked about in the following thread:

https://forum.arctic-sea-ice.net/index.php/topic,2839.msg232576.html#msg232576

An awesome image of the area I'm referring to, as posted by uniquorn in the above thread


45
Arctic sea ice / Re: The 2019/2020 freezing season
« on: October 24, 2019, 09:48:54 PM »
I think the corresponding shape of ice-covered areas on the one hand and higher surface temperature anomalies on the other hand can be easily explained. If in the long term (e.g. median 1981-2010) a certain area of the Arctic Ocean has been usually covered with ice at a certain date and this year it is not, the difference in surface temperature (ice-covered = well below - 2°C; ice-free = above -1.8°C, maybe above 0°C) must be clearly visible in the SST anomaly map.

Exactly. That's a much better explanation than I gave. The air has a much lower specific heat capacity than water, so water is the temperature 'buffer'. Once ice forms the ocean can no longer transfer heat to the air as effectively, and the temperatures will tend to the long term average.
What about that heating 1 m3 of Water requires the same amount of energy as heating 3,000 m3 of air?
What about thermal conductivity?

Add wind, sea ice drift, ocean swells, cloud, fog and suddenly we are talking models with big computers and they still get it wrong.

46
Arctic sea ice / Re: "Stupid" Questions :o
« on: October 22, 2019, 05:58:25 PM »
Good questions, thank you Macid.


Answering your last question first, my thermal conductivity calculation was for an illustrative 'toy model' that might approximate the true situation in some circumstances. The whole point is to get the magnitude of the heat flux for the process of thermal conduction -- which was found to be of order 1/100 W/m^2.

..
I still don't understand, how can you use a very thin slice of a full model to approximate the true situation? I think I found a better approximation in this article: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6114986/

Quote
Before the 2000s, typical BG halocline heat content per unit area was around 2 × 108 J m−2 (Fig. 2A). Since that time, there has been a sustained increase in heat content per unit area (local values reach beyond 4 × 108 J m−2 in the 2014–2017 time period), with maximal values centered over the Canada Basin coincident with the climatological BG center (Fig. 2) (1). Over the period 1987–2017, total warm halocline heat content integrated horizontally over a region encompassing the BG has nearly doubled (Fig. 3A). It is instructive to set the resulting heat content increases in context alongside sea ice. The capacity for sea ice melt of the additional heat content (the increase of ~2 × 108 J m−2 over 30 years) equates to a change of about 0.8 m in thickness, taking the latent heat of melting to be 2.67 × 105 J kg−1 and the density of sea ice to be 900 kg m−3.

47
Please stop trolling sark, he is doing important stream of consciousness work on a phenomenon that will likely change all of our lives.

If you read Sark's postings as a neo-post-apocalyptic poetry, then they are fine. Perhaps they should have their own "arctic literature" thread.

Try to get any relatable information whatsoever out of them is hopeless. El Cid was just posting what perhaps a lot of us are thinking.

48
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: October 18, 2019, 11:40:40 AM »
Thin ice melts faster than thick ice.  See this image from the previously linked reference:




Even at 3 m thick ice, 3% of incident radiation on Aug 6th somewhere on the Beaufort Sea makes it to the oceans. At 1 m as much as 15% makes it to the ocean.  The thinner the ice gets from there the more energy the ice lets through.

Then you start taking into account mechanical strength, fractures on the ice and geometry...

49
I would propose we re-dub our current year -12. By all accounts 2031 is our new year 0. We just have not yet acknowledged it.

It is interesting to consider what the practical implications would be of a BOE. Like, heavy snows beginning in August, no cohesive polar vortex, and dual vortices establishing themselves early in Eurasia and North America. At that point the only remaining MYI may actually be sheltered in Hudson or Kara or Okhotsk (or some combo of the three) in addition to the CAA and southern CAB.

When the event begins, as it did in the Younger Dryas, the snowfall will not stop for the next summer in the coldest locations. Imagine winter 2014-15 in Boston, but tack on another 100" in March, and then in April, with another 50" in May and continued snows into June before insolation ultimately does the trick (for the last time in a long time).

How much snow will it take until the interstates are unusable? How much SWE will it take before roofs start caving in? How deep does the snow have to get before the power fails? How frequently do storms have to occur for maintenance to become impossible?

If a population is frozen in place, with no way to escape, and the power fails, there would be guaranteed mass death occurring in short order. Such an event would be much more democratic than heatwaves, where air conditioners provide relief for some.

What use is a generator when it is encased in snow 10' deep, and you can't vent through your roof because it is also covered in snow XX feet deep, and the power goes out? At that point, you are dead, and so is everyone else. Either from freezing, running out of food, carbon monoxide, or your roof caving in.

History indicates this is precisely what happened at the onset of the Younger Dryas. It didn't happen everywhere -- the Southeast US was safe -- but where onset occurred, the switch flipped instantaneously, in the span of a year. It is because the impending event is due to cascading impacts that will only be realized to be "final" (for our purposes) after they have already occurred.

#blackpill

50
Arctic sea ice / Re: When will the Arctic Go Ice Free?
« on: October 12, 2019, 08:34:19 PM »
All good points philopek, but here is an alternate view:   

Those are valid ways to see things. As we all know it's quite complex system about which it's hard or even impossible to tell exactly what happens and certainly even harder to tell exactly when and in which order.

Therefore it's a good thing to think through things from various angles. The only opinions I have serious issues with is "re-glaciation" or a long term rebound while the rest of the planet including it's oceans is getting warmer and gaining momentum doing so.

I for on am very reluctant to discuss whether we lost and/or are currently loosing ice mass, for me it's a fact that we do, while how fast and touching which way-points in the process some can make educated guesses bordering to calculations, most of us can make educated guesses based on observations and information form places like the ASIF and those who promote outrageous provocations for profiling purposes I try to avoid with intermittent success ;)

Thanks for your contribution, very much appreciated, content and attitude wise.

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