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Messages - Jim Williams

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1
Please remember:--

Occam's razor
KISS (Keep It Simple, Stupid!)

Ding et al 2017 have blinded me with science (I am not competent to judge their methods) and just leave me trying to decide whether there is truth in their summary.
By Occam's razor, earlier forcasts that predicted climate change as a result of increased CO2 (especially in polar regions) appear to coming true, so extra complicated models with all manner of caveats just serve to confuse (or encourage cherry-picking?) and are not necessary.
As people see it, it will come down to "60% natural variability (+40% human influence?)" versus "human influence" - there is a common factor if it is mentioned!
KISS!
Actually, I think that is more in keeping with the definition of a prophet (one who only makes predictions which turn out to come to pass), but I have to agree that we ought to pay more attention to those who warned us that CO2 would cause the the air to warm than to those who stir the pot and say it wasn't so much the CO2.

Occam's razor, though stated in several forms, is more along the lines of: don't suggest more entities (causes) than you need to to explain the data.

2
Re: energy to melt arctic ice

The Arctic floating icecap annually melts and refreezes aprroximately 20,000 Gigatons. If the ice were land based, this would correspond to a sea level rise and fall of 60 mm annually. The amount of heat involved  is close to the net  yearly radiative imbalance. Net Radiative imbalance from 1972-2008 due to greenhouse gases is  5.6e21 J/yr or about 183 Terawatt for the whole earth(Church,2011,  doi:10.1029/2011GL048794).

sidd
Probably need to move this off into Stupid Questions or some such, but TheUAoB's original question "Surely the metric that really counts is total sea-ice mass.  Volume doesn't describe the quality/density of the ice any more than extent or area shows thickness" and your interesting reply has peaked my interest...so.

Do you think you can convert your cost to melt what is in fact melted into a cost to melt it all (either in Joules or Terawatts)?  It might also be interesting to do that as percentages of current mass and current excess heat.  Sort of a ball-park, how close are we really to a Blue Ocean Event?

3
Surely the metric that really counts is total sea-ice mass.  Volume doesn't describe the quality/density of the ice any more than extent or area shows thickness.

I see Area/extent as a "compression" of volume. The compression allows for simpler understanding of some phenomena highly related to area at the cost of the information lost during the compression.

Volume and mass combine to give us density. Density is probably a very good indicator of actual ice conditions, however spatial information that volume provides is lost.

How useful knowing the Mass alone would be? I guess it will give the capacity of the ice to overcome waves, export and other physical interactions, but spatial information would be lost.

Actually, the metric being looked for is total energy required to melt -- and no, I do not know how to obtain that.

4
Arctic sea ice / Re: The 2017 melting season
« on: March 22, 2017, 08:44:26 PM »
For max snowfall you need a warmish atmosphere with lots of water vapor and temperatures around freezing. Too cold and rel humidity is lower and snow flakes are too small. Around and little above zero C flakes are at their largest and depth builds quickly. A little warmer and it's rain... no I do not see that happening....a ton of snow that melts quickly....

Agreed.  That has been the recent history.

5
Arctic sea ice / Re: Latest PIOMAS update (March)
« on: March 22, 2017, 05:14:18 PM »
Latest daily volume numbers file while official site is not providing it.
Same file cleaned up in Google Sheets and re-exported as CSV.  (It is a .CSV file, but I could not upload that type so I renamed it as txt.)  No idea what I am going to do with it now that I have it, but I figured it would be an easier format for many to deal with.

As an aside, I know it is an artifact of the decimal system and the units of measurement but the way vol under 10 showed up as a new column I had to clean up and then increased in size was striking.

6
Arctic sea ice / Re: The 2016/2017 freezing season
« on: March 21, 2017, 05:42:33 PM »
While we have hit the maximum extent, this freezing season thread should continue to track growth in volume through April. Hopefully, the ice in the CAB continues to strengthen.

Hope springs eternal....however....when was the volume peak 200 years ago verses when this year?

7
Science / Re: Validation of GCM Models
« on: March 21, 2017, 03:58:29 PM »
<snip; N.>

8
Science / Re: Validation of GCM Models
« on: March 21, 2017, 12:29:23 PM »
Neven - You haven't moderated Jim W's apology have you?

Jim W. - At the risk of repeating myself, you've flung the vaguest of insults loudly in my direction. Please state your case or apologise.

Alternatively, in some words I picked up off ex Prof. Judy’s cutting room floor:

https://andthentheresphysics.wordpress.com/2017/02/05/expose-david-rose-does-not-understand-baselines/#comment-91207

Thank you for your attention.
I do not remember saying anything to you, and I do not apologise for stating facts -- the GCM are pure crap.

9
Arctic sea ice / Re: The 2017 melting season
« on: March 21, 2017, 12:17:39 PM »
Before we get too deep into melting season, would some of the more seasoned posters mind giving a handful of things they will be keeping an eye on over the next few months to judge how 'good' or 'bad' the melt is going?

This will be my (and I suspect some others) first melting season so it'd be nice to know what to expect in general, as well as what to watch coming from such an extreme freezing season.

My quick and off the cuff list might be as follows:
1: What real world empirical  data can we trust regarding the state of the halocline. -once the besieged lower salinity surface waters are exported and corrupted by salt enrichment from the winter there can be no winter refreeze.
2: How much water vapour is smoking in to the zone on unforeseen atmospheric circulation systemic reformations. - as it phase transitions from vapour to liquid or even more so importantly from liquid to solid it emits photons in all directions, most importantly downwards, that are precisely the frequency for the reverse transition of water molecules in the reverse homily to elevate their energy level via a melt or boil.
3: How much export transport of ice out of the basin is current and ongoing, what salt/ water ratio is part of this equation,  with implications obvious for (1)
I have to agree totally with this list, and I had not considered the implications of ice export for the fresh-water lens before.

I'll be watching mostly the DMI 80N, and the reasons Hyperion gave are the reasons I'll be watching.

10
Science / Re: Validation of GCM Models
« on: March 20, 2017, 12:50:26 PM »
If I am right, then nothing I/we do now makes a bit of difference.  The war was lost 200 years ago.

Great, so the only reason you post here, is to vent your frustrations. That's not the intended use of the ASIF, so any more denier-mirror Dunning-Kruger BS or disrespect shown to people who engage with you and take the time to refer you to stuff (the 'herd' of persecutors), and I'm putting you under moderation.

Your actions and what you say don't match. A true doomer wouldn't be wasting time on some obscure forum. He'd be listening to Bach and reading Tolstoy. Go punch a bag or something.

Normally I'd PM this, but I've let this go on for long enough.
I come here to watch the ice melt.

11
...is that I believe this particular paper by Ding et al makes a dangerous argument at a critical time in human history.
OK...What is dangerous about it, and why should he not make a dangerous argument?

My vague sense in scanning it that it is crap, but the only thing dangerous about crap are the worms which might wait within it.


12
Arctic sea ice / Re: The 2017 melting season
« on: March 19, 2017, 10:00:44 PM »
I don't think so Neven, the increase is consistent with the models and warmer/wetter atmospheric circulation moving further northward
And windier, the denser it's packed the more water it will represent when melted.
I have to agree with this line of thought.  For now it is Warm Arctic, Cold Continents....complete with snow.  I do not see new ice sheets in our immediate future.


13
Arctic sea ice / Re: The 2017 melting season
« on: March 19, 2017, 09:56:14 PM »
I wonder if enhanced Siberian snowcover is playing a part in this?
Do you know the play Rosencrantz and Guildenstern Are Dead?  ( https://en.wikipedia.org/wiki/Rosencrantz_and_Guildenstern_Are_Dead )

14
Science / Re: Validation of GCM Models
« on: March 19, 2017, 09:34:14 PM »
Being an admirer of Paul Feyerabend, I am probably a bit more relaxed about hard and fast definitions of science than some on this thread. Feyerabend maintained that the idea that science can or should operate according to universal and fixed rules is unrealistic, pernicious, and detrimental to science itself.

At the moment, I'm not so interested in notions of verification, "the old guard" & etc but whether the quote posted by AbruptSLR has any credence...

"Scientists are now saying it might already be too late to avoid a temperature rise of up to 7.36 degrees Celsius (13.25 degrees Fahrenheit) above pre-industrial levels by 2100.
That's way above the upper limit of 4.8 degrees Celsius (8.6 degrees Fahrenheit) predicted by the Intergovernmental Panel on Climate Change (IPCC) in 2014, and to make matters worse, a new study suggests that we're underestimating just how sensitive Earth is to greenhouse gases.

Climate models are useful for these predictions but do CMIP5 models consistently underestimate because of "missing feedbacks": Is this why the paleo based models ALSR quotes show a much more dangerous future than the models.
...

I don't know what AbruptSLR has to say, but I say they have as much credence as any other predictions we have for more than about 10 days into the future right now.

I don't know which climate models you are talking about, but the models receiving all the funding seem to have less skill than some which are being panned by "The Scientists."  Can't say that I see any of them as better than casting bones so far.

(Note: some of the seasonal models are beginning to show signs of life.)


15
Science / Re: Validation of GCM Models
« on: March 19, 2017, 09:24:35 PM »
I'm not interested in proving anything to others.  I'm only interested in preventing people from pretending something totally unproven is truth and trying to use that to influence others.


These are contradicting statements. How are you going to prevent people from "pretending something totally unproven"? You must convince them. The only civilized way I know to do that is by proving to them that you are right. So you are either contradicting yourself  or your method to stop people is uncivilized.

I am more afraid of technical fixes than I am of what I expect to happen if we do nothing.

That sounds to me like people that are afraid of vaccines but embrace homeopathy.

 You must understand that we are not doing nothing. Our fossil fuel energy use, rampant deforestation and intensive agriculture are consuming and changing the planet whether we like it or not. We seem powerless to stop it. There are too many people making too much money, and the threat seems too distant to do anything about. We are already engineering the planet, if you count randomly braking shit as engineering.

If you and me are right and the Arctic goes this year and doesn't come back I can almost guarantee you that we will regret not having done whatever we could while there was time.

We are uncivilized.  Learn that.


If I am right, then nothing I/we do now makes a bit of difference.  The war was lost 200 years ago.


16
Science / Re: Validation of GCM Models
« on: March 19, 2017, 09:21:12 PM »
Did you really expect me to spend 2 hours???

I most certainly do, if that's how long it takes.

No wonder I tend to ignore you when you say anything other than pure direct data.  You are asking me to waste my time before giving me a reason to waste it.

Don't you understand economics at all???????

17
I'm getting 404 Not Found for the DMI website today. 'Sup? Maintenance, perhaps?
The directory appears to be empty.  I'd guess a machine crashed -- and it is Sunday.

18
Science / Re: Validation of GCM Models
« on: March 19, 2017, 04:00:36 PM »

I'll guess that the ice goes this Summer and does not return next Winter.  I might not be right this year, but I'll be right before the GCM are.

Ok. But how do you prove that to others? Just wait for it to happen? Just send an e-mail to Trump: "hey man the arctic is melting, perhaps you should do something about it"?

No. The only way you can prove that to others is to spend the next few years developing a verifiable mathematical framework that shows others why your guess is worth doing something about. At that point your guess may be better than the GCM. But right now your guess is mostly useless, unless you can convince others. As your guess is useless, but GCM's is a useful tool in many different ways, GCm's guess is better.

I happen to completely disagree with you about validation by peers -- that simply isn't how Science actually progresses.  It generally progresses by the old guard dying off.

I'm sorry, but there are many ways that science progresses. Sometimes you just have to wait for the old guard to die, but many times the evidence is overwhelming, sometimes the tools improve, sometimes there is a paradigm shit in the collective thinking.

For example, if you and I are right and the Arctic does collapse this year and it doesn't comeback there will be an immediate paradigm shift. The old guard might not simply die of old age (although many may die due to the chaos). In that case the science will change because the evidence is overwhelming.

Also, there is a lag in science. Events must happen first, then data is collected and studied. Extensive writing and verification happens and then the results are published.  This sometimes takes years. It may very well be that later this year and in the years afterward the accuracy of the models improve enough to predict if and when the Arctic will collapse. The capacity of the models to improve over time also makes them a better guess than yours.

I'm not interested in proving anything to others.  I'm only interested in preventing people from pretending something totally unproven is truth and trying to use that to influence others.

I am more afraid of technical fixes than I am of what I expect to happen if we do nothing.

19
Science / Re: Validation of GCM Models
« on: March 19, 2017, 02:33:51 PM »
Business opportunities and climate change - ExIST quarterly event - March 2017 ?

That's the one Jim. What's your question?

Did you really expect me to spend 2 hours???

20
Science / Re: Validation of GCM Models
« on: March 19, 2017, 02:32:47 PM »
In case some people didn't read the linked article entitled: “The feedback paradox”.  The increasing insurance losses associated with pronounced natural variations imply high climate sensitivity; which provides more motivation to take climate action now, even though our climate models are not perfect.

https://andthentheresphysics.wordpress.com/2017/03/14/the-feedback-paradox/

Extract: “Any feedback process based on temperature will act on both natural and forced changes in the temperature. If such feedbacks result in pronounced natural temperature variations, they also imply that the climate sensitivity is high.”
While I happen to be of the opinion it is much too late to bother, I will agree that taking action now would at least prepare the populace for the coastline changes which will be coming.

The one big worry I have is that people will try using these GCM to attempt some sort of "Engineering Fix" which I would expect to most likely make things worse in some unknown unknown way.

Disclaimer:  My guess is no better than the GCM guess -- and theirs is no better than mine.

So you think that a limited amount of adaptive engineering may be warranted (or maybe not); however, what type of measures do you think are warranted to promote a reduction in anthropogenic GHG emissions (a carbon fee and dividend program, regulations, government investment in sustainable energy, government promoting energy efficiency, etc.)?

Warranted technically -- none, as I think it much too late to bother.

Warranted socially -- I'd say cap and trade would probably have the largest emotional impact with the least additional disruption.  The real object in my mind would be to prepare people for having to move -- and for what will happen to millions unable to move.

21
Science / Re: Validation of GCM Models
« on: March 18, 2017, 11:15:56 PM »

Disclaimer:  My guess is no better than the GCM guess -- and theirs is no better than mine.


What is your guess? what is the uncertainty of your guess?

My guess is that ice goes this year and the atmosphere of the NH goes bunkers causing chaos around the planet. If the ice doesn't go this year and the pacific AND Atlantic cool, then we might get up to ten years of ice and not so extreme atmospheric conditions in the meantime. If the Atlantic and Pacific do not cool then we'll be out of ice before 2020 with the corresponding chaos.

Regrettably I don't have the capacity to offer verifiable proof for my dates and time frames to other people . My guess is unverifiable. I believe it to be a good guess because I'm trying to constantly challenge my knowledge and so far things look bleak. But my methods do not have the rigorosity required.

On the other hand GCM's guesses can be verified by every person fluent in the language of that particular science. Since many people have agreed using the same definitions and found their guess a valid one, the guesses of the GCM's are better guesses than mine.

That does not mean GCM guesses are right, but because they can be verified by many people and are constantly updating, the chances of the GCM's to be right are higher than mine. Just like any knowledge tool. It is useful but it has limitations.

I'll guess that the ice goes this Summer and does not return next Winter.  I might not be right this year, but I'll be right before the GCM are.

I happen to completely disagree with you about validation by peers -- that simply isn't how Science actually progresses.  It generally progresses by the old guard dying off.

22
Science / Re: Validation of GCM Models
« on: March 18, 2017, 11:11:22 PM »
Jim W - This is probably of no interest to you, but I recently had a long discussion at the UK Met Office about their "unified" model that handles both their "weather" and "climate" forecasting. Here you go:

http://forum.arctic-sea-ice.net/index.php/topic,256.msg106820.html#msg106820

Now what exactly is the point that you are endeavouring, but failing, to make? You've presumably heard the old adage attributed to George Box that "all models are wrong, but some of them are useful"?


Business opportunities and climate change - ExIST quarterly event - March 2017 ?


23
Science / Re: Validation of GCM Models
« on: March 18, 2017, 09:23:15 PM »
In case some people didn't read the linked article entitled: “The feedback paradox”.  The increasing insurance losses associated with pronounced natural variations imply high climate sensitivity; which provides more motivation to take climate action now, even though our climate models are not perfect.

https://andthentheresphysics.wordpress.com/2017/03/14/the-feedback-paradox/

Extract: “Any feedback process based on temperature will act on both natural and forced changes in the temperature. If such feedbacks result in pronounced natural temperature variations, they also imply that the climate sensitivity is high.”
While I happen to be of the opinion it is much too late to bother, I will agree that taking action now would at least prepare the populace for the coastline changes which will be coming.

The one big worry I have is that people will try using these GCM to attempt some sort of "Engineering Fix" which I would expect to most likely make things worse in some unknown unknown way.

Disclaimer:  My guess is no better than the GCM guess -- and theirs is no better than mine.


24
Science / Re: Validation of GCM Models
« on: March 18, 2017, 09:03:54 PM »
Jim I have to ask you: what point it is you are trying to make here? I think anyone paying attention fully understands by now that a) you don't like GCMs, b) you think they're all worthless garbage, and c) there's literally no extant source supporting the validity of any GCM that you will accept as credible. So what are you aiming for? What is it you want to hear? I doubt whether you're going to make everyone here--or, hell, anyone here--smack themselves on the forehead and exclaim, "Oh! Williams is right! GCMs really are crap!" Neither is it likely that the climatologists, mathematicians, and software programmers who have devoted decades of their professional lives to the development and constant tweaking of these GCMs are going to read your comments, come to the realization that they've wasted their careers chasing a chimera, and quit to become Uber drivers or chambermaids or meat packers or whatever. So, again: what are you hoping to accomplish? What response are you wishing to see? Or to put it another way: is there any response that will satisfy you? If the answer is yes, let us know; be explicit instead of dismissive, and we'll see what we can do. But if the answer is no, aren't you just wasting your time? And ours?

Remember: sometimes in life, people will disagree with you because they're stupider and/or more ignorant than you. But sometimes they'll disagree with you because, you now, you're wrong.
So far they seem to be disagreeing with me because I'm not part of the herd.  No one has even slightly demonstrated that I am wrong, as all I have asserted is that there is no evidence that the GCM are right -- and their response was to call me an idiot rather than provide a shred of evidence.

So far the only evidence I have seen on the skill of the GCM are complaints here that they are proving to be way too conservative; which I take as evidence tending to deny the validity of the GCM.


25
Science / Re: Validation of GCM Models
« on: March 18, 2017, 08:53:07 PM »
I think when it comes to risk management models, the insurance industry is going to look at what is most likely the worst. Not some some Guy M. kind of worst, but something that has a fair probability of coming too pass. After all their bread and butter comes from skimming the difference between what may happen and what doesn't. So I will ask, what are they seeing in the models that would bring forth the following statement? "Davidson said recent data that has been collected but has yet to be made official indicates sea levels could rise by roughly 3 meters or 9 feet by 2050-2060, far higher and quicker than current projections. Until now most projections have warned of seal level rise of up to 4 feet by 2100."
http://www.insurancejournal.com/news/national/2016/04/12/405089.htm
Those numbers are well outside the ones we see commonly presented. The implications that those numbers represent to all of humanity..... well I see no need to preach to the choir. Let us hope their wrong, but even if they are, it is still going to cost us literally. They will be hedging their bets that their right. Their bets are our premiums.


I think you might be one of the few here who get the point.  Seems the "scientists" are too busy playing with their peers to bother doing any real science.


26
Science / Re: Validation of GCM Models
« on: March 18, 2017, 05:18:32 PM »
GCMs are not a crystal ball. They don't predict future forcing or volcanoes or aerosol or sun intensity .They can only assume a certain path. Therefore as a prediction tool on themselves to tell you what will the sea level or the temperature will be at a particular time they will utterly fail. If you run them multiple times with particular forcing etc you can start understanding how the system works and what a possible future outcome be. They are an incomplete experimental tool that allows you to run experiments and see I there is sth you are missing and also guide you to what might occur. You completely misunderstand their use or utility. 

Weather models are like GCMs with better resolution run constantly constrained by observations. Their path in use is narrow and most variables well defined. Hence the 10 day accuracy.

Anyway,  I am talking to the wind....
There is one obvious difference between the weather models and the GCM.  The weather models are tested every day and the GCM have been tested never.

27
Science / Re: Validation of GCM Models
« on: March 18, 2017, 05:16:27 PM »
Translation:  We cannot validate the models.

To me it means: "we can validate the models but with uncertainties"

That is the best possible truth that a person could possibly hope for.  There is no such thing as 100% certainty. Even the most basic facts of life, like "the sun will come out tomorrow", have uncertainties. But for humans to deal with uncertainties inherent of everything, we ignore the uncertainties and make every decision based on incomplete information. 

So for as long as you understand that there is uncertainty in the models they are useful. If you understand what the uncertainties are, the models are even more useful. However , if you expect 0% uncertainty, what you are expecting is a lie. Such a thing simply does not exist within our limited senses.

When it comes to climate models, they are only a guide, a very educated guess of what the future might look like. For what they are, they are marvels of modern engineering.

Well, maybe we can within the realm of having uncertainty, but it hasn't happened yet.  I do not think the models are science.

I think the best data I have seen on the validation of the GCM so far is the complaint of many here on the forum that the models are being way too conservative -- i.e., are invalid.

I don't care how well educated the people making the models are...I care how stupid the people using them are.


28
Science / Re: Validation of GCM Models
« on: March 18, 2017, 03:43:51 PM »
Jim,
  The arguments you pose seem to be philosophical and not technical/scientific.  I counter-propose that you study chapter 9 of the latest IPCC report (Evaluation of Climate Models) and detail what you find lacking.

If you have cogent views they will surely get addressed.

https://www.ipcc.ch/pdf/assessment-report/ar5/wg1/WG1AR5_Chapter09_FINAL.pdf

Regards,
  CB

From section 9.1.1:

The direct approach to model evaluation is to compare model output
with observations and analyze the resulting difference. This requires
knowledge of the errors and uncertainties in the observations, which
have been discussed in Chapters 2 through 6. Where possible, averages
over the same time period in both models and observations are
compared, although for many quantities the observational record is
rather short, or only observationally based estimates of the climatological
mean are available. In cases where observations are lacking,
we resort to intercomparison of model results to provide at least some
quantification of model uncertainty via inter-model spread.

Translation:  We cannot validate the models.

29
Science / Re: Validation of GCM Models
« on: March 18, 2017, 02:18:05 PM »
I want to make it clear that I do not deny climate change, quite the opposite.

So far the only "validation" I've seen of the GCM are the completely valid complaints of people on this forum that the models are way too conservative  i.e.  invalid.

Since I'm of the opinion that what we are seeing now is due to the Industrial Revolution 200 years ago and we ain't seen nothing yet, it pains me to see models which have 0 demonstrated skill quoted as fact.

Does anyone have any actual data at all which would tend to confirm the timelines and quantities these GCM predict?  (Or for that matter any actual data to deny other than the rumblings of some of us here on this forum?)

30
Science / Re: Validation of GCM Models
« on: March 18, 2017, 02:02:59 PM »
http://cmip-pcmdi.llnl.gov/cmip5/index.html

That page used the word "Predictions" exactly once, and it was not clear to me how to find said predictions and how they compared to subsequent events.

Hindcasts and intercomparisons do not actually validate anything.

31
Science / Re: Validation of GCM Models
« on: March 18, 2017, 01:56:29 PM »
https://andthentheresphysics.wordpress.com/

That led to this: https://andthentheresphysics.wordpress.com/2017/02/21/judith-curry-confuses-laypeople-about-climate-models/ (which is itself interesting) which led to this http://www.thegwpf.org/content/uploads/2017/02/Curry-2017.pdf  ::

Executive Summary
There is considerable debate over the fidelity and utility of global climate models
(GCMs). This debate occurs within the community of climate scientists, who disagree
about the amount of weight to give to climate models relative to observational analyses.
GCM outputs are also used by economists, regulatory agencies and policy makers,
so GCMs have received considerable scrutiny from a broader community of scientists,
engineers, software experts, and philosophers of science. This report attempts
to describe the debate surrounding GCMs to an educated but nontechnical audience.
Key summary points
• GCMs have not been subject to the rigorous verification and validation that is
the norm for engineering and regulatory science.
• There are valid concerns about a fundamental lack of predictability in the complex
nonlinear climate system.
• There are numerous arguments supporting the conclusion that climate models
are not fit for the purpose of identifying with high confidence the proportion
of the 20th century warming that was human-caused as opposed to natural.
• There is growing evidence that climate models predict too much warming from
increased atmospheric carbon dioxide.
• The climate model simulation results for the 21st century reported by the Intergovernmental
Panel on Climate Change (IPCC) do not include key elements
of climate variability, and hence are not useful as projections for how the 21st
century climate will actually evolve.
Climate models are useful tools for conducting scientific research to understand the
climate system. However, the above points support the conclusion that current GCMs
are not fit for the purpose of attributing the causes of 20th century warming or for
predicting global or regional climate change on timescales of decades to centuries,
with any high level of confidence. By extension, GCMs are not fit for the purpose of
justifying political policies to fundamentally alter world social, economic and energy
systems. It is this application of climate model results that fuels the vociferousness of
the debate surrounding climate models.


Nothing on this path contradicted the claim that the models have not been validated.


32
Arctic sea ice / Re: Stupid Questions :o
« on: March 18, 2017, 01:30:17 PM »


Can you just provide me with century long statistics on their +/- error rate please?  I have no interest in happenstance at all.
This type of manufactured doubt is like a cancer that has infected our society, and it shouldn't be allowed to spread. Reading it here makes me furious.

You cannot just brush off two research papers with a single inane sentence and expect to be taken seriously. The papers have already been peer-reviewed and published, they speak for themselves. You're the one that made the claim, the onus is on you to show us how they're "happenstance".

It is painfully obvious that you do not know how a computer model of even the most simple of things actually works.

Does this guy only attack "climate" models? What about the thousands of other models that we use on a daily basis? Are they happenstance when right too? Disgusting.
The weather reports are getting quite strongly validated and have been demonstrated to work fairly well to about 10 days now.  I see no EVIDENCE that the GCM can make any better prediction -- and actually have never seen any evidence they can even do 10 days.

If you have such evidence then please present it over in the GCM validation thread under SCIENCE.

33
Science / Re: Validation of GCM Models
« on: March 18, 2017, 02:38:40 AM »
The linked thread entitled: "Climate Model Test Beds: Calibrating Nonlinear ESMs focused on ACME" compares observations to model predictions, with the goal of refining the models:

https://forum.arctic-sea-ice.net/index.php/topic,1478.0.html
Hi Abrupt,

I'll believe that the comparisons are buried in there somewhere, and I will continue to comb through the tome looking for them, but on the whole the thread seems more concerned with perfecting, and not with testing.

What do you know specific to the question of things which the GCM have predicted for particular date ranges and what then happened as of those dates.  That is...can you restrict yourself to the question of skill and provide data about their skill?  (Obviously, we are interested in the statistics, not mere happenstances.)

34
Arctic sea ice / Re: Stupid Questions :o
« on: March 18, 2017, 02:13:46 AM »
It is not bad to admit that you have absolutely no clue how the models work... it ok but do not project your ignorance to the models or the scientists running them...

I do not care how they work, I care that they do not work.  I am rejecting an appeal to authority here.

And that is exactly what you just made.

Jim you need to get out more.  Not all models are the same. HadGEM1 has done a very reasonable job modelling recent ice losses and several papers have been written:
A case study of a modelled episode of low Arctic sea ice, Keen, A.B., Hewitt, H.T. & Ridley, J.K.  2013
Mechanisms causing reduced Arctic sea ice loss in a coupled climate model, A. E. West, A. B. Keen, and H. T. Hewitt, 2013


Can you just provide me with century long statistics on their +/- error rate please?  I have no interest in happenstance at all.


35
Arctic sea ice / Re: IJIS
« on: March 18, 2017, 02:04:11 AM »
The optimist in me reminds us that the sun always starts shining in the Arctic at this time of year.  Also, that peak ice is not statistically predictive of September minimums.

you're totally right of course while i think that those who expect a low minimum have the bad state of the ice, including the lack of very thick ice. converting ice volume into energy needed to melt it we are more sooner than later reaching a state where ANY weather and ANY summer condition will do the job, simply because the energy needed is so low due to the small amount of ice (volume) to melt.

Actually, I think it is the poor state of the cold since December 2015.  Which of the hot southern oceans and the open northern waters is more to blame I will leave to others.

36
Science / Re: Validation of GCM Models
« on: March 18, 2017, 01:34:16 AM »
I'm going to leave this open for now, even though it was posted in the wrong category, doesn't clearly state what it's about (models or the validation thereof?), and previous off-topic discussions in other threads showed a lack of nuance, mainly from the thread starter.

But maybe someone has something interesting to say about models that we haven't heard before (we already know the 'all of them wrong, some useful' quote ;) ).

I went looking for anything resembling validation of the models and the best I could find was a paper that discussed the code itself.

If anyone can find something on the validation of the actual predictions generated by the models which is more formalized than what we have discovered for ourselves over the last few years I'd like to read it.  (Comparisons of predictions against subsequent events only please.  Nothing post hoc.)


37
Science / Validation of GCM Models
« on: March 17, 2017, 11:23:27 PM »
I will start by rejecting them, and bring in the question of the structure of the models as my argument.  They smell geopolitical rather than scientific"

http://www.geosci-model-dev.net/8/1221/2015/gmd-8-1221-2015.pdf

"5 Conclusions
These software architecture diagrams show, in a broad sense,
how climate models work: how the climate system is divided
into components and how these components communicate
with each other. They also illustrate the similarities and differences
between the eight models we have analyzed. Some
models, particularly in North America, exhibit a high level of
encapsulation for each component, with all communication
managed by the coupler. Other models, particularly in Europe,
implement a binary atmosphere–ocean architecture that
simplifies the coupling process. Institutions focus their efforts
on different climatic processes, which eventually cause
different components and subcomponents to dominate each
model’s source code. However, not all models are completely
independent of each other: modeling groups commonly exchange
pieces of code, from individual routines up to entire
components. Finally, climate models vary widely in complexity,
with the total line count varying by a factor of 20
between the largest GCM and the smallest EMIC we analyze
(Fig. 9). Even when restricting this comparison to the
six GCMs, there is still a factor of 7 variation in total line
count.
Our analysis also offers new insights into the question
of model diversity, which is important when creating multimodel
ensembles. Masson and Knutti (2011) and Knutti et al.
(2013) showed that models from the same lab tend to have
similar climatology, even over multiple model generations.
We believe this can be explained, at least in part, in terms of
their architectural structure and the distribution of complexity
within the model. As Knutti et al. (2013) suggest, “We
propose that one reason some models are so similar is because
they share common code. Another explanation for the
similarity of successive models in one institution may be that
different centers care about different aspects of the climate
and use different data sets and metrics to judge model ‘quality’
during development.” Our analysis offers preliminary evidence
to support both of these hypotheses. We hypothesize
further that the relative size of each component within an
Earth system model indicates the relative size of the pool of
expertise available to that lab in each Earth system domain
(once adjustments are made for components imported from
other labs). The availability of different areas of expertise at
each lab may provide a sufficient explanation for the clustering
effects reported by Masson and Knutti (2011) and Knutti
et al. (2013). Furthermore, the two analyses are complementary:
while our analysis looks at model code without considering
its outputs, Masson and Knutti (2011) and Knutti et al.
(2013) analyze model outputs without looking at the code.
Our diagrams may prove to be useful for public communication
and outreach by their host institutions. The inner
workings of climate models are rarely discussed in the media,
even by science reporters; as such, these pieces of software
are fundamentally mysterious to most members of the public.
Additionally, the diagrams could be used for communication
between scientists, both within and across institutions. It can
be extremely useful for climate scientists, whether they are
users or developers of coupled models, to understand how
other modeling groups have addressed the same scientific
problems. A better understanding of the Earth system models
used by other institutions may open doors for international
collaboration in the years to come

38
Arctic sea ice / Re: The Slow Transition
« on: March 17, 2017, 01:53:04 AM »
<snip>

39
Arctic sea ice / Re: Stupid Questions :o
« on: March 17, 2017, 01:47:52 AM »
It is not bad to admit that you have absolutely no clue how the models work... it ok but do not project your ignorance to the models or the scientists running them...
I do not care how they work, I care that they do not work.  I am rejecting an appeal to authority here.

And that is exactly what you just made.

40
Arctic sea ice / Re: The 2017 melting season
« on: March 17, 2017, 12:48:01 AM »
<snip, you're not paying attention>

41
Arctic sea ice / Re: The Slow Transition
« on: March 15, 2017, 08:03:02 PM »
New paper by R. Bintanja and O. Andry:

Towards a rain-dominated Arctic


Abstract:
Climate models project a strong increase in Arctic precipitation over the coming century, which has been attributed primarily to enhanced surface evaporation associated with sea-ice retreat. Since the Arctic is still quite cold, especially in winter, it is often (implicitly) assumed that the additional precipitation will fall mostly as snow. However, little is known about future changes in the distributions of rainfall and snowfall in the Arctic. Here we use 37 state-of-the-art climate models in standardized twenty-first-century (2006–2100) simulations to show a decrease in average annual Arctic snowfall (70°–90°N), despite the strong precipitation increase. Rain is projected to become the dominant form of precipitation in the Arctic region (2091–2100), as atmospheric warming causes a greater fraction of snowfall to melt before it reaches the surface, in particular over the North Atlantic and the Barents Sea. The reduction in Arctic snowfall is most pronounced during summer and autumn when temperatures are close to the melting point, but also winter rainfall is found to intensify considerably. Projected (seasonal) trends in rainfall and snowfall will heavily impact Arctic hydrology (for example, river discharge, permafrost melt), climatology (for example,snow, sea-ice albedo and melt) and ecology (for example, water and food availability)




Smells Post Hoc to me.

We are watching the Arctic melt therefore the models are tweaked to show the Arctic melting.

42
Arctic sea ice / Re: Stupid Questions :o
« on: March 15, 2017, 07:41:09 PM »
Or: Why should we treat 2 degrees C as anything other then pure magical thinking?

Jim, what do you mean here? 2°C isn't a number pulled from GCMs - or even a consensus of  scientists.  It's essentially a political statement.  That we can keep global temperatures below 2°C from pre-industrial probably does require magical thinking, but again that's neither the fault of models or climate scientists.

My point is the whole of GCM is essentially magical thinking -- as far as I can tell from the evidence.

What I fault is paying any attention at all to the GCM absent evidence of "skill."  It would be correct if I had never heard of them.


43
Arctic sea ice / Re: Stupid Questions :o
« on: March 15, 2017, 05:05:30 PM »
Let me phrase my stupid question a slightly different way.  What evidence do we have that we are using the right kind of mathematics for predicting what will happen in a discrete discontinuous system over a long period of time?  (Long being over about a month.)
Kinda rhetorical, Jim, but we don't. What we have is the output of the models themselves.

I really don't think the reduction of skill with time is a result of the math. I think it is a result of the inputs, their granularity, and our understanding of the system mechanics.

I'll agree that right now the major error is our lack of data on the initial conditions, with lack of understanding of the mechanics coming in a close second, but it still seems to me that using a math which models temperature as a continuous "Real" variable rather than as billions of discrete changes will simply never be able to make accurate long range predictions.  Discrete Topology simply isn't the same math as continuous vector fields.  In particular, the group of Integers has all sorts of funky subgroups and other properties that only show up with very large numbers.
You must be a god if you want to abandon the thermodynamic equillibria assumptions  and try solve the underlying discrete quantum equations with 10^26 or more degrees of freedom... to end up getting similar results because the thermodynamics models have been working really well for centuries.
Do you know that in every breath you take there is a 99.99% probability of you taking at least one molecule of air that Caesar expelled when he said "et tu Brute"?
I think climate and weather models are well above the head of most of us here and I personally let specialists do their job and deliver their breakthroughs when they come with one.
No...I am a primitive Buddhist:  No essence.  No permanence.  No perfection.

I just don't think this kind of math will prove to be of utility with this kind of system for detailed predictions longer than a few weeks.  You will need the computing power of the whole Universe just to keep up with what is happening outside your window.

I will ask the same question again in another form.  What evidence do we have that this is even a reasonable method for accurately modelling long-term climate?   Or: Why should we treat 2 degrees C as anything other then pure magical thinking?

44
Arctic sea ice / Re: Stupid Questions :o
« on: March 15, 2017, 01:42:04 PM »
Let me phrase my stupid question a slightly different way.  What evidence do we have that we are using the right kind of mathematics for predicting what will happen in a discrete discontinuous system over a long period of time?  (Long being over about a month.)
Kinda rhetorical, Jim, but we don't. What we have is the output of the models themselves.

I really don't think the reduction of skill with time is a result of the math. I think it is a result of the inputs, their granularity, and our understanding of the system mechanics.

I'll agree that right now the major error is our lack of data on the initial conditions, with lack of understanding of the mechanics coming in a close second, but it still seems to me that using a math which models temperature as a continuous "Real" variable rather than as billions of discrete changes will simply never be able to make accurate long range predictions.  Discrete Topology simply isn't the same math as continuous vector fields.  In particular, the group of Integers has all sorts of funky subgroups and other properties that only show up with very large numbers.


45
Arctic sea ice / Re: Stupid Questions :o
« on: March 14, 2017, 05:36:30 PM »
Let me phrase my stupid question a slightly different way.  What evidence do we have that we are using the right kind of mathematics for predicting what will happen in a discrete discontinuous system over a long period of time?  (Long being over about a month.)

46
Arctic sea ice / Re: Stupid Questions :o
« on: March 14, 2017, 04:22:47 PM »
My stupid question of the day:  Are there any climate models out there that use system dynamics rather than trying to model a natural system for any length of time by pretending it is a linear vector space and using arrays of differential equations?
It is difficult to understand the question Jim, because I see both options you give as equivalent. An array of differential equations applied over a vectorial quantity ("linear"?) or several scalar and vectorial quantities, can be a mathematical model of a dynamical system, suitable for performing computations and developing predictions of the underlying dynamical system.

To oversimplify, I am interested in a model that represents information as sources and sinks, and the system as buckets.  In the extreme, the information would be represented as single photons, but that is clearly not computable with current hardware (unless you count the Universe as current hardware).

Fields are a pretty approximation when you are only guessing 10 days out.  They really suck bad over the long haul.  (There is nothing less real than a Real number.)

Per Wiki:
... model dynamics is formulated in terms of the hydrostatic primitive equations with a terrain following pressure vertical coordinate (h). The time discretization is an implicit two-time-level semi-Lagrangian scheme. The spatial discretization is a Galerkin grid-point formulation on an Arakawa C-grid in the horizontal (lat-lon) and an unstaggered vertical discretization. The horizontal mesh can be of uniform or variable resolution, and furthermore can be arbitrarily rotated, the vertical mesh is also variable. The explicit horizontal diffusion is -2 on all prognostic variables.

The operational GEM model is interfaced with a full complement of physical parametrizations, these currently include:

  • solar and infrared radiation interactive with water vapor, carbon dioxide, ozone and clouds,
  • prediction of surface temperature over land with the force-restore method,
  • turbulence in the planetary boundary layer through vertical diffusion, diffusion coefficients based on stability and turbulent kinetic energy,
  • surface layer based on Monin-Obukhov similarity theory,
  • shallow convection scheme (non precipitating),
  • Kuo-type deep convection scheme (global forecast system),
  • Fritsch-Chappell type deep convection scheme (regional forecast system),
  • Sundqvist condensation scheme for stratiform precipitation,
  • gravity wave drag.

I have zero interest in "model dynamics."  Your point?

47
Arctic sea ice / Re: Stupid Questions :o
« on: March 14, 2017, 03:12:28 PM »
My stupid question of the day:  Are there any climate models out there that use system dynamics rather than trying to model a natural system for any length of time by pretending it is a linear vector space and using arrays of differential equations?
It is difficult to understand the question Jim, because I see both options you give as equivalent. An array of differential equations applied over a vectorial quantity ("linear"?) or several scalar and vectorial quantities, can be a mathematical model of a dynamical system, suitable for performing computations and developing predictions of the underlying dynamical system.

To oversimplify, I am interested in a model that represents information as sources and sinks, and the system as buckets.  In the extreme, the information would be represented as single photons, but that is clearly not computable with current hardware (unless you count the Universe as current hardware).

Fields are a pretty approximation when you are only guessing 10 days out.  They really suck bad over the long haul.  (There is nothing less real than a Real number.)


48
Arctic sea ice / Re: Stupid Questions :o
« on: March 14, 2017, 02:17:42 PM »
My stupid question of the day:  Are there any climate models out there that use system dynamics rather than trying to model a natural system for any length of time by pretending it is a linear vector space and using arrays of differential equations?

49
Arctic sea ice / Re: Stupid Questions :o
« on: March 14, 2017, 02:06:37 PM »
...
But even with an all-year ice-free arctic, sinking will always take place due to cooling. Even if the oceans were both totally ice-free and totally salt free, the Gulf Stream would still bring excess warmth from mid latitudes towards the Arctic Ocean.

I think the flies in the ointment here are Asia and North America.  Land both warms and cools more rapidly than water.  So, what the Gulf Stream giveth Asia taketh away.

On the scale of a couple thousand years you get extreme warming.  On the scale of 10s of thousands of years you get extreme cooling.  On the scale of eons you get a wild flip-flop.

50
Arctic sea ice / Re: Stupid Questions :o
« on: March 14, 2017, 01:36:37 PM »
Just supposing the ice was so smashed as to be practically liquid, and that every tide that flowed in from the north atlantic displaced ice or water from the upper layer of the arctic,[through CAA Nares, + Fram] how long would it take to flush the ice/top 2m.?

i think no-one can tell because it depends on too many unpredictable variables but then, i'm totally sure, that we shall be able to witness this happening and not so far out and we shall know.

it's not an english saying but it goes about like: it's happening while we're asking when it will happen :-) bad translation perhaps but should be comprehensible at least :-)
I think the English equivalent would be "Look out your window."

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