Arctic Sea Ice : Forum

AGW in general => Science => Topic started by: Jim Williams on March 17, 2017, 11:23:27 PM

Title: Validation of GCM Models
Post by: Jim Williams 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 (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
Title: Re: Validation of GCM Models
Post by: Neven on March 18, 2017, 12:28:39 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 ;) ).
Title: Re: Validation of GCM Models
Post by: Jim Williams 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.)

Title: Re: Validation of GCM Models
Post by: AbruptSLR on March 18, 2017, 02:20:06 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
Title: Re: Validation of GCM Models
Post by: Jim Williams 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.)
Title: Re: Validation of GCM Models
Post by: sidd on March 18, 2017, 04:12:25 AM
http://cmip-pcmdi.llnl.gov/cmip5/index.html (http://cmip-pcmdi.llnl.gov/cmip5/index.html)
Title: Re: Validation of GCM Models
Post by: AbruptSLR on March 18, 2017, 11:53:53 AM
While I personally believe that the CMIP5 GMSTA projections err on the side of least drama, ESLD; nevertheless, the first attached image released by Gavin Schmidt comparing the observed GMSTA through the middle of 2016 to the radiative forcing adjusted CMIP5 projections, confirms at least that: (a) the faux pause is nothing more than a blip in the general warming trend and that (b) as indicated by relatively complex ESM projections, we are now entering a period of accelerating global warming (and reasonable people can argue about just how fast this acceleration will be with continued anthropogenic radiative forcing).

The second attached image compares GISTEMP to CMIP5 values and comes from the linked article entitled: "Messing about with model-obs comparisons".  While the graph comes with some disclaimers, it does give one pause for thought about where we are likely headed.

https://andthentheresphysics.wordpress.com/ (https://andthentheresphysics.wordpress.com/)


The third attached image comes from my Reply #1553 in the "Conservative Scientists & its Consequences" and compares how projections based on recent paleo-based data compares to those for CMIP5

http://forum.arctic-sea-ice.net/index.php/topic,1053.0.html (http://forum.arctic-sea-ice.net/index.php/topic,1053.0.html)

The linked article helps to clarify how higher the paleo-based climate sensitivity that Friedrich et al (2016) found vs CMIP5 (see attached image):

http://www.sciencealert.com/scientists-say-it-could-already-be-game-over-for-climate-change (http://www.sciencealert.com/scientists-say-it-could-already-be-game-over-for-climate-change)

Extract: "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.

From this data, they concluded that Earth becomes more sensitive to warming in interglacial warming phases (periods between ice ages), like the one we're now in.

The researchers also calculated there will be a "likely" temperature increase of between 4.78 and 7.36 degrees Celsius (8.6 and 13.25 degrees Fahrenheit) above pre-industrial levels over the next 85 years if greenhouse gas emissions continue at their current rate,.
That means it's absolutely vital that we get those emissions down as quickly as possible.
Because a 7.36-degree Celsius (13.25-degree Fahrenheit) rise would effectively be "game over" for the planet as we know it, climatologist Michael Mann from Penn State University, who wasn't involved in the research, told Ian Johnston at The Independent."


For other discussions on how conservative the CMIP5 projections are likely to be, you can also look at posts in the 'Human Stupidity' thread at the following link:

http://forum.arctic-sea-ice.net/index.php/topic,1548.0.html (http://forum.arctic-sea-ice.net/index.php/topic,1548.0.html)

Lastly, I provide the fourth attached image showing the timing of the various efforts to calibrate CMIP6.
Title: Re: Validation of GCM Models
Post by: Jim Williams on March 18, 2017, 01:56:29 PM
https://andthentheresphysics.wordpress.com/ (https://andthentheresphysics.wordpress.com/)
That led to this: https://andthentheresphysics.wordpress.com/2017/02/21/judith-curry-confuses-laypeople-about-climate-models/ (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 (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.

Title: Re: Validation of GCM Models
Post by: Jim Williams on March 18, 2017, 02:02:59 PM
http://cmip-pcmdi.llnl.gov/cmip5/index.html (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.
Title: Re: Validation of GCM Models
Post by: Jim Williams 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?)
Title: Re: Validation of GCM Models
Post by: CognitiveBias on March 18, 2017, 03:18:04 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 (https://www.ipcc.ch/pdf/assessment-report/ar5/wg1/WG1AR5_Chapter09_FINAL.pdf)

Regards,
  CB
Title: Re: Validation of GCM Models
Post by: Jim Williams 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 (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.
Title: Re: Validation of GCM Models
Post by: Archimid on March 18, 2017, 04:00:01 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.

 
Title: Re: Validation of GCM Models
Post by: DrTskoul on March 18, 2017, 04:11:59 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....
Title: Re: Validation of GCM Models
Post by: Jim Williams 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.

Title: Re: Validation of GCM Models
Post by: Jim Williams 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.
Title: Re: Validation of GCM Models
Post by: DrTskoul on March 18, 2017, 05:42:46 PM
Sigh....
Title: Re: Validation of GCM Models
Post by: AbruptSLR on March 18, 2017, 05:48:02 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?)

When first you cite an "... and Then There's Physics" article on how Judith Curry confuses lay people and then you quote a Judith Curry article as evidence that your position is correct; you raise a lot of doubts about what your motivation is to question the validity of GCMs.  If GCMs underestimate the coming climate impacts, then one should be motivated to more quickly reduce anthropogenic radiative forcing; rather than to repeat that "All models are wrong ..." and forget to indicate that "... but some models are useful", in order to take action now.

The world's most accurate GCM is the Accelerated Climate Model for Energy, ACME; for which Phase I is scheduled to be complete in 2017.  Using logic like that presented by Judith Curry, the Trump Administration could say that such an improved model is still not perfect and thus suppress the publications of findings from ACME; however, a citizen sitting on a civil lawsuit jury panel would only hold GCM projections to a burden of proof that the: "Preponderance of the evidence, also known as balance of probabilities, is the standard required in most civil cases..."

https://en.wikipedia.org/wiki/Burden_of_proof_(law) (https://en.wikipedia.org/wiki/Burden_of_proof_(law))

Soon the Trump Administration will find that the Judicial Branch of government will only hold GCM's to this standard of proof (see the following linked thread entitled: "Legal Approach to Climate Change Resolutions")

http://forum.arctic-sea-ice.net/index.php/topic,1207.100.html (http://forum.arctic-sea-ice.net/index.php/topic,1207.100.html)

Edit: See also the linked article entitled: "'Biggest Case on the Planet' Pits Kids vs. Climate Change".

http://news.nationalgeographic.com/2017/03/kids-sue-us-government-climate-change/ (http://news.nationalgeographic.com/2017/03/kids-sue-us-government-climate-change/)

Abstract: "A pioneering lawsuit against the U.S. government on global warming won the right to a trial. Now Trump wants an appeals court to cancel it."
Title: Re: Validation of GCM Models
Post by: Jim Pettit on March 18, 2017, 05:55:03 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.
Title: Re: Validation of GCM Models
Post by: AbruptSLR on March 18, 2017, 06:26:33 PM
When determining how accurate GCMs need to be for the judicial branch to hold the executive branch accountable for taking action to fight climate change, one only needs to look at the record of increasing insurance losses from the increasingly violent natural disasters.

In this regards, the linked article is entitled: "Climate change threatens ability of insurers to manage risk", and discusses how large the "protection gap" has already grown to, and indicates that the insurance industry's traditional approach to climate risk management are already ineffective:

https://www.theguardian.com/environment/2016/dec/07/climate-change-threatens-ability-insurers-manage-risk (https://www.theguardian.com/environment/2016/dec/07/climate-change-threatens-ability-insurers-manage-risk)

Extract: "The ability of the global insurance industry to manage society’s risks is being threatened by climate change, according to a new report.

The report finds that more frequent extreme weather events are driving up uninsured losses and making some assets uninsurable.

The analysis, by a coalition of the world’s biggest insurers, concluded that the “protection gap” – the difference between the costs of natural disasters and the amount insured – has quadrupled to $100bn (£79bn) a year since the 1980s."

The ClimateWise report, published on Wednesday, also says the industry must also use its risk management expertise to convince policymakers in both the public and private sector of the urgent need for climate action.

The industry’s traditional response to rising insurance risks – raising premiums or withdrawing cover – would not help deal with the rising risks of global warming, it said.


“The insurance industry’s role as society’s risk manager is under threat,” said Maurice Tulloch, chairman of global general insurance at Aviva and chair of ClimateWise. “Our sector will struggle to reduce this protection gap if our response is limited to avoiding, rather than managing, society’s exposure to climate risk.”

See the following linked article entitled: "Climate protection gap widening, warns insurance report":

http://www.bbc.com/news/science-environment-38229108 (http://www.bbc.com/news/science-environment-38229108)

See also the following linked article that indicates that the insurance industry paid-out $50 billion for natural disasters in 2016 (uninsured losses were $125 billion), as compared to $27 billion in 2015.

http://www.reuters.com/article/us-disaster-insurance-idUSKBN14O0XG (http://www.reuters.com/article/us-disaster-insurance-idUSKBN14O0XG)

Title: Re: Validation of GCM Models
Post by: Red on March 18, 2017, 07:21:59 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 (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.
Title: Re: Validation of GCM Models
Post by: AbruptSLR on March 18, 2017, 08:34:24 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.”
Title: Re: Validation of GCM Models
Post by: Jim Williams 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 (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.

Title: Re: Validation of GCM Models
Post by: Jim Williams 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.

Title: Re: Validation of GCM Models
Post by: Neven on March 18, 2017, 09:09:38 PM
So, basically everyone here is part of a herd and is trying to persecute you. And the problems with models is that they aren't showing that there will be a catastrophe, meaning they're not valid and not real science.

Does that about sum up your current grievances?
Title: Re: Validation of GCM Models
Post by: Jim Williams 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.

Title: Re: Validation of GCM Models
Post by: Cid_Yama on March 18, 2017, 09:31:23 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.

Eli has hit the nail on the head.  This guy is just attempting to manufacture doubt about climate models and scientists.

He has already defended Creationism here and called PIOMAS and GCMs Alchemy.  It is pretty clear where he is coming from and what he is up to.

http://forum.arctic-sea-ice.net/index.php/topic,1903.msg105850.html#msg105850 (http://forum.arctic-sea-ice.net/index.php/topic,1903.msg105850.html#msg105850)
Title: Re: Validation of GCM Models
Post by: Jim Hunt on March 18, 2017, 09:34:21 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 (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"?
Title: Re: Validation of GCM Models
Post by: Archimid on March 18, 2017, 09:44:12 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.
Title: Re: Validation of GCM Models
Post by: Jim Williams 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 (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 ?

Title: Re: Validation of GCM Models
Post by: Jim Williams 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.
Title: Re: Validation of GCM Models
Post by: Chuck Yokota on March 19, 2017, 12:06:03 AM
I think that where Jim Williams goes wrong is in the expectation that GCMs should be expected, or are designed, to make predictions about events in the next few years. It is a fundamental confusion between what is weather and what is climate. Climate is the long-term statistics of weather, or when the climate is out of equilibrium (as with excess greenhouse gases adding energy to the Earth system) the change in the long-term statistics of weather as the system moves to re-establish equilibrium.

Notice the words "long-term" and "statistics". GCMs are concerned with how the Earth system changes in accordance with the laws of physics, reflected in how the statistics of weather will change in statistically significant periods of time, i.e. greater than 30 years. Short-term trends will be affected by chaotic and random factors such as volcanic eruptions, weather--chaotic in periods of days and weeks, and multi-year and multi-decadal oscillations whose causes are poorly understood. That is the value of hindcasting; by plugging in the actual forcing events of a number of years, researchers can see how well or poorly the model results reflect the historical results.

To use a simple analogy: Statistics can tell us that a fair six-sided die will come to rest with equal probability with any number up. It is helpless to predict what the outcome of the next roll will be. Weather forecasting would analogously be observing the flight of the die when it is thrown, measuring the translational and rotational velocities, plugging in the elastic coefficients of the die and table, the coefficient of friction, air resistance, and so forth, to make a prediction of how the die will come to rest.

Of course, climate models have a lot more to work with than an idealized die, and so have much more to say about the shape of the future climate.
Title: Re: Validation of GCM Models
Post by: Jim Hunt on March 19, 2017, 12:32:24 AM
Business opportunities and climate change - ExIST quarterly event - March 2017 ?

That's the one Jim. What's your question?
Title: Re: Validation of GCM Models
Post by: AbruptSLR on March 19, 2017, 12:57:36 AM
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.)?
Title: Re: Validation of GCM Models
Post by: Jim Williams 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.
Title: Re: Validation of GCM Models
Post by: Jim Williams 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???
Title: Re: Validation of GCM Models
Post by: Archimid on March 19, 2017, 02:44:04 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.
Title: Re: Validation of GCM Models
Post by: Jim Williams 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.
Title: Re: Validation of GCM Models
Post by: Gray-Wolf on March 19, 2017, 05:23:21 PM
http://journals.ametsoc.org/doi/pdf/10.1175/1520-0469%281967%29024%3C0241%3ATEOTAW%3E2.0.CO%3B2 (http://journals.ametsoc.org/doi/pdf/10.1175/1520-0469%281967%29024%3C0241%3ATEOTAW%3E2.0.CO%3B2)

This from 1967 seems to still pass muster???

I think the Paid deniers boxed clever over the worst of the Asian dimming knowing that The naturals were already on a cool footing? Now we are back out of that period and into aggressive warming everything looks fine again with us now outstripping model projections ( wiggles both above and below the trend line show the natural variability?).

Do you think we will be causing the same kind of issues now that the naturals favour warming and so boost yearly temps as the Paid deniers did over the years they fell short? I think not. models were always more of a route map than a moment by moment projection of what will come to pass and they have been doing just fine in that role whilst fools argue over their minutia.......
Title: Re: Validation of GCM Models
Post by: Archimid on March 19, 2017, 06:00:54 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. 
Title: Re: Validation of GCM Models
Post by: Jim Hunt on March 19, 2017, 06:23:19 PM
Did you really expect me to spend 2 hours???

I most certainly do, if that's how long it takes.
Title: Re: Validation of GCM Models
Post by: GeoffBeacon on March 19, 2017, 07:20:31 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 (https://en.wikipedia.org/wiki/Epistemological_anarchism) 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 (http://www.brusselsblog.co.uk/carbon-budgets-a-straightforward-answer-from-decc/)": Is this why the paleo based models ALSR quotes show a much more dangerous future than the models.

The presence of these known "missing feedbacks" makes me want to sympathise with a bit of Jim Williams opener
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.
It took me much effort to get a statement on missing feedbacks from a UK government department (That was the Department of Energy and Climate Change - just before they were abolished). This was another example of why I do not unreservedly trust all climate scientists working for (or closely with) UK government.

If Masson and Knutti were really successful in making climate models more transparent it would be a leap forward - but is it a leap that is possible?  If, for the average citizen, the questions we ask were still hard work, it would make it easier for trusted experts to advise us. (e.g. Is the increase in forest fires adequately covered in Model ?A)


P.S. I was asked to take some photos at an event yesterday, which gave me the opportunity to speak to an ex Secretary of State of the department that sponsored the Met Office & Hadley Centre. In office, he hadn't seen the problem of undue influence from his department but did comment on the role of HM Treasury - but I've heard that before. I wasn't completely reassured by what he said. The department is very keen on economic growth & business continuity and growth increases climate change.  (Lord Stern once said that  if it’s a race between growth and the environment, growth will always win (http://www.brusselsblog.co.uk/depressing-news-growth-trumps-the-environment/).)

P.P.S. OK, "All model are wrong, but some useful". Actually aren't most to them useful?
However, could we say "All CMIP5 models are useful but nearly all underestimate our problem"?

P.P.P.S. If the models do underestimate, do we play into the deniers' hands by admitting it?
Title: Re: Validation of GCM Models
Post by: wili on March 19, 2017, 07:34:21 PM
GB wrote that ASLR quoted:
"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.

Wow. I missed that one, Geoff. Could you or ASLR or anyone provide the linky?

ETA: Ah, I think I found it. I supply it here in case others are curious: http://www.sciencealert.com/scientists-say-it-could-already-be-game-over-for-climate-change (http://www.sciencealert.com/scientists-say-it-could-already-be-game-over-for-climate-change)
Title: Re: Validation of GCM Models
Post by: crandles on March 19, 2017, 08:17:38 PM
GB wrote that ASLR quoted:
"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.

Wow. I missed that one, Geoff. Could you or ASLR or anyone provide the linky?

ETA: Ah, I think I found it. I supply it here in case others are curious: http://www.sciencealert.com/scientists-say-it-could-already-be-game-over-for-climate-change (http://www.sciencealert.com/scientists-say-it-could-already-be-game-over-for-climate-change)

A different commentary on the paper
https://julesandjames.blogspot.co.uk/2016/11/apocalpyse-now.html (https://julesandjames.blogspot.co.uk/2016/11/apocalpyse-now.html)
Title: Re: Validation of GCM Models
Post by: Jim Williams 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???????
Title: Re: Validation of GCM Models
Post by: Jim Williams 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.

Title: Re: Validation of GCM Models
Post by: Jim Williams 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 (https://en.wikipedia.org/wiki/Epistemological_anarchism) 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 (http://www.brusselsblog.co.uk/carbon-budgets-a-straightforward-answer-from-decc/)": 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.)

Title: Re: Validation of GCM Models
Post by: Neven on March 19, 2017, 10:09:36 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.
Title: Re: Validation of GCM Models
Post by: SteveMDFP on March 19, 2017, 10:22:44 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???????

When one posts provocative or controversial statements on a public forum, you take up the time of dozens of people who may feel a need to investigate, refute, or refine the assertions.
Yes, you DO have a responsibility to take the time to read the background of the matter, think carefully about it, and craft a thoughtful message before posting.  All else is trolling.
Title: Re: Validation of GCM Models
Post by: Archimid on March 20, 2017, 01:06:48 AM
We are uncivilized.  Learn that.

This is a civil forum. If you are not at least attempting civility, then you are just trolling. I think that the only reason you are still receiving comments is because you have made insightful statements before. Most anybody else would have been silence by now.

It also appears as if you are 100% sure, no place for uncertainty, that the Arctic will collapse this year. We differ in that respect. I know that I could be wrong. Actually I still think that the most likely outcome is that the ice recovers for at least a few more years.  I only give it 30%-50% chance for the ice to go. Last year I gave it a 10% to 30%.

I also think that there is much that can be done to save much of what we have. I recommend you to not lose hope, maybe that is why you seem to have fallen in despair.  Even if the worst comes there is hope.
Title: Re: Validation of GCM Models
Post by: AbruptSLR on March 20, 2017, 01:16:39 AM
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.

Geoff,

So that you can decide for your, I selected the following 28 references [not including either von der Heydt et. al. 2016 nor Friedrich et al (2016)] that either directly, or indirectly, indicate that climate sensitivity is most likely significantly higher than the range summarized by AR5:

1. The linked reference analyses the CMIP3&5 results to conclude the ECS is likely 3.9C +/- 0.45C:

Chengxing Zhai, Jonathan H. Jiang & Hui Su (2015), "Long-term cloud change imprinted in seasonal cloud variation: More evidence of high climate sensitivity", Geophysical Research Letters, DOI: 10.1002/2015GL065911


http://onlinelibrary.wiley.com/doi/10.1002/2015GL065911/full (http://onlinelibrary.wiley.com/doi/10.1002/2015GL065911/full)

2. The linked reference provides findings from CMIP5 of the continued poleward expansion of the Hadley Cell with continued global warming; which in-turn supports the idea that ECS is greater than 3C:

Lijun Tao, Yongyun Hu & Jiping Liu (May 2016), "Anthropogenic forcing on the Hadley circulation in CMIP5 simulations", Climate Dynamics, Volume 46, Issue 9, pp 3337-3350 DOI: 10.1007/s00382-015-2772-1

http://rd.springer.com/article/10.1007%2Fs00382-015-2772-1 (http://rd.springer.com/article/10.1007%2Fs00382-015-2772-1)

3. The linked reference presents new paleo evidence about the Eocene.  While the authors emphasize that their findings support the IPCC interpretation for climate sensitivity, when looking at the attached Fig 4 panel f, it appears to me that this is only the case if one averages ECS over the entire Eocene; while if one focuses on the Early Eocene Climate Optimum (EECO) which CO₂ levels were higher than in current modern times, it appear that ECS was higher (around 4C) than the IPCC AR5 assumes (considering that we are increasing CO2 concentrations faster now that during the EECO this gives me concern rather than reassurance).

Eleni Anagnostou, Eleanor H. John, Kirsty M. Edgar, Gavin L. Foster, Andy Ridgwell, Gordon N. Inglis, Richard D. Pancost, Daniel J. Lunt & Paul N. Pearson (2016), "Changing atmospheric CO2 concentration was the primary driver of early Cenozoic climate", Nature, doi:10.1038/nature17423


http://www.nature.com/nature/journal/vaop/ncurrent/full/nature17423.html (http://www.nature.com/nature/journal/vaop/ncurrent/full/nature17423.html)

4. Tan et al (2016) indicates that ECS may well be between 5.0 and 5.3C.

Ivy Tan, Trude Storelvmo & Mark D. Zelinka (08 Apr 2016), "Observational constraints on mixed-phase clouds imply higher climate sensitivity", Science, Vol. 352, Issue 6282, pp. 224-227, DOI: 10.1126/science.aad5300


http://science.sciencemag.org/content/352/6282/224 (http://science.sciencemag.org/content/352/6282/224)

5. According to the IPCC AR5 report: "The transient climate response is likely in the range of 1.0°C to 2.5°C (high confidence) and extremely unlikely greater than 3°C"; however, the linked reference uses only observed data to indicate that TCR is 2.0 +/- 0.8C.  Thus AR5 has once again erred on the side of least drama.


T. Storelvmo, T. Leirvik, U. Lohmann, P. C. B. Phillips & M. Wild (2016), "Disentangling greenhouse warming and aerosol cooling to reveal Earth’s climate sensitivity", Nature Geoscience, doi:10.1038/ngeo2670


http://www.nature.com/ngeo/journal/vaop/ncurrent/full/ngeo2670.html (http://www.nature.com/ngeo/journal/vaop/ncurrent/full/ngeo2670.html)

6. The linked reference reassesses ECS from CMIP3 &5 and find an ensemble-mean of 3.9C, and I note that CMIP3&5 likely err on the side of least drama as they ignore several important non-linear slow feedbacks that could be accelerated by global warming:

Chengxing Zhai, Jonathan H. Jiang, Hui Su (2015), "Long-term cloud change imprinted in seasonal cloud variation: More evidence of high climate sensitivity", Geophysical Research Letters, DOI: 10.1002/2015GL065911

http://onlinelibrary.wiley.com/doi/10.1002/2015GL065911/full (http://onlinelibrary.wiley.com/doi/10.1002/2015GL065911/full)

7. The linked reference could not make it more clear that paleo-evidence from inter-glacial periods indicates that ECS is meaningfully higher than 3C and that climate models are commonly under predicting the magnitude of coming climate change.

Dana L. Royer (2016), "Climate Sensitivity in the Geologic Past", Annual Review of Earth and Planetary Sciences, Vol. 44


http://www.annualreviews.org/doi/abs/10.1146/annurev-earth-100815-024150?src=recsys (http://www.annualreviews.org/doi/abs/10.1146/annurev-earth-100815-024150?src=recsys)

8. Thompson indicates that ECS has a 95%CL range of from 3C to 6.3C, with a best estimate of 4C, and Sherwood (2014) has a higher value still:

Climate sensitivity by Roy Thompson published by Earth and Environmental Science Transactions of the Royal Society of Edinburgh, DOI: 10.1017/S1755691015000213

http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=10061758&fileId=S1755691015000213 (http://journals.cambridge.org/action/displayAbstract?fromPage=online&aid=10061758&fileId=S1755691015000213)


9. Tian (2015) indicates that the double-ITCZ bias constrains ECS to its high end (around 4.0C):

Tian, B. (2015), "Spread of model climate sensitivity linked to double-Intertropical Convergence Zone bias", Geophys. Res. Lett., 42, doi:10.1002/2015GL064119.


http://onlinelibrary.wiley.com/doi/10.1002/2015GL064119/abstract (http://onlinelibrary.wiley.com/doi/10.1002/2015GL064119/abstract)

10. Sherwood et al (2014), which found that ECS cannot be less than 3C, and is likely currently in the 4.1C range.  Also, everyone should remember that the effective ECS is not a constant, and models project that following a BAU pathway will result in the effective ECS increasing this century:


Sherwood, S.C., Bony, S. and Dufresne, J.-L., (2014) "Spread in model climate sensitivity traced to atmospheric convective mixing", Nature; Volume: 505, pp 37–42, doi:10.1038/nature12829

http://www.nature.com/nature/journal/v505/n7481/full/nature12829.html (http://www.nature.com/nature/journal/v505/n7481/full/nature12829.html)

11. The linked reference studies numerous climate models and finds that: "… those that simulate the present-day climate best even point to a best estimate of ECS in the range of 3–4.5°C."
Reto Knutti, Maria A. A. Rugenstein (2015), "Feedbacks, climate sensitivity and the limits of linear models", Philosophical Transactions of the Royal Society A, DOI: 10.1098/rsta.2015.0146

http://rsta.royalsocietypublishing.org/content/373/2054/20150146 (http://rsta.royalsocietypublishing.org/content/373/2054/20150146)

12.  The linked reference indicates that the cloud feedback from tropical land is robustly positive.  As AR5 did not know whether this contribution to climate sensitivity was positive or negative, this clearly indicates that AR5 errs on the side of least drama with regard to both TCR & ECS:

Youichi Kamae, Tomoo Ogura, Masahiro Watanabe, Shang-Ping Xie and Hiroaki Ueda (8 March 2016), "Robust cloud feedback over tropical land in a warming climate", Atmospheres, DOI: 10.1002/2015JD024525

http://onlinelibrary.wiley.com/doi/10.1002/2015JD024525/abstract (http://onlinelibrary.wiley.com/doi/10.1002/2015JD024525/abstract)

13.  Graeme L. Stephens, Brian H. Kahn and Mark Richardson (5 May, 2016), "The Super Greenhouse effect in a changing climate", Journal of Climate, DOI: http://dx.doi.org/10.1175/JCLI-D-15-0234.1 (http://dx.doi.org/10.1175/JCLI-D-15-0234.1)


http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-15-0234.1 (http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-15-0234.1)

14. The linked reference assumes different degrees of nonlinearity for climate feedback mechanisms and concludes that such nonlinearity for positive feedback represents a Black Swan risk that linear climate models cannot recognize:

Jonah Bloch-Johnson, Raymond T. Pierrehumbert & Dorian S. Abbot (24 June 2015), "Feedback temperature dependence determines the risk of high warming", Geophysical Research Letters, DOI: 10.1002/2015GL064240

http://onlinelibrary.wiley.com/doi/10.1002/2015GL064240/full (http://onlinelibrary.wiley.com/doi/10.1002/2015GL064240/full)


15.  While the linked (open access) reference has many appropriate qualifying statements and disclaimers, it notes that the AR5 paleo estimates of ECS were linear approximations that change when non-linear issues are considered.  In particular the find for the specific ECS, S[CO2,LI], during the Pleistocence (ie the most recent 2 million years) that:
"During Pleistocene intermediate glaciated climates and interglacial periods, S[CO2,LI] is on average ~ 45 % larger than during Pleistocene full glacial conditions."

Therefore, researchers such as James Hansen who relied on paleo findings that during recent full glacial periods ECS was about 3.0C, did not know that during interglacial periods this value would be 45% larger, or 4.35C.

Köhler, P., de Boer, B., von der Heydt, A. S., Stap, L. B., and van de Wal, R. S. W. (2015), "On the state dependency of the equilibrium climate sensitivity during the last 5 million years", Clim. Past, 11, 1801-1823, doi:10.5194/cp-11-1801-2015.


http://www.clim-past.net/11/1801/2015/cp-11-1801-2015.html (http://www.clim-past.net/11/1801/2015/cp-11-1801-2015.html)
http://www.clim-past.net/11/1801/2015/cp-11-1801-2015.pdf (http://www.clim-past.net/11/1801/2015/cp-11-1801-2015.pdf)

16.  The linked reference implies that climate sensitivity (ESS) could be much higher than previously assumed:

Jagniecki,Elliot A. et al. (2015), "Eocene atmospheric CO2from the nahcolite proxy", Geology, http://dx.doi.org/10.1130/G36886.1 (http://dx.doi.org/10.1130/G36886.1)


http://geology.gsapubs.org/content/early/2015/10/23/G36886.1 (http://geology.gsapubs.org/content/early/2015/10/23/G36886.1)

17.  The linked open access reference identifies three constraints on low cloud formation that suggest that cloud feedback is more positive than previously thought.  If verified this would mean that both TCR and ECS (and ESS) are larger than previously thought:

Stephen A. Klein and Alex Hall (26 October 2015), "Emergent Constraints for Cloud Feedbacks", Climate Feedbacks (M Zelinka, Section Editor), Current Climate Change Reports, pp 1-12, DOI 10.1007/s40641-015-0027-1

http://link.springer.com/article/10.1007%2Fs40641-015-0027-1 (http://link.springer.com/article/10.1007%2Fs40641-015-0027-1)

18.  The linked article indicates that values of TCR based on observed climate change are likely underestimated:

J. M. Gregory, T. Andrews and P. Good (5 October 2015), "The inconstancy of the transient climate response parameter under increasing CO₂", Philosophical Transactions of the Royal Society A, DOI: 10.1098/rsta.2014.0417


http://rsta.royalsocietypublishing.org/content/373/2054/20140417 (http://rsta.royalsocietypublishing.org/content/373/2054/20140417)

19.  The linked reference indicates that most current climate models underestimate climate sensitivity:

J. T. Fasullo, B. M. Sanderson & K. E. Trenberth (2015), "Recent Progress in Constraining Climate Sensitivity With Model Ensembles", Current Climate Change Reports, Volume 1, Issue 4, pp 268-275, DOI 10.1007/s40641-015-0021-7

http://link.springer.com/article/10.1007/s40641-015-0021-7?wt_mc=email.event.1.SEM.ArticleAuthorOnlineFirst (http://link.springer.com/article/10.1007/s40641-015-0021-7?wt_mc=email.event.1.SEM.ArticleAuthorOnlineFirst)

20.  The linked reference indicates that studies that assuming linearity of climate sensitivity likely underestimate the risk of high warming.

Jonah Bloch-Johnson, Raymond T. Pierrehumbert and Dorian S. Abbot (June 2015), "Feedback temperature dependence determines the risk of high warming", Geophysical Research Letters, DOI: 10.1002/2015GL064240

http://onlinelibrary.wiley.com/doi/10.1002/2015GL064240/abstract (http://onlinelibrary.wiley.com/doi/10.1002/2015GL064240/abstract)

21. The linked reference indicates that new research (from PlioMIP2) demonstrates that the climate sensitivity for the Pliocene was higher than previously believed (from PlioMIP1):

Kamae, Y., Yoshida, K., and Ueda, H.: Sensitivity of Pliocene climate simulations in MRI-CGCM2.3 to respective boundary conditions, Clim. Past, 12, 1619-1634, doi:10.5194/cp-12-1619-2016, 2016.

http://www.clim-past.net/12/1619/2016/ (http://www.clim-past.net/12/1619/2016/)

http://www.clim-past.net/12/1619/2016/cp-12-1619-2016.pdf (http://www.clim-past.net/12/1619/2016/cp-12-1619-2016.pdf)


22. The linked reference indicates that corrected recent observations indicate that the most likely value of ECS may be as high as 4.6C (see attached plot of the time dependent curve):

Kyle C. Armour  (27 June 2016), "Projection and prediction: Climate sensitivity on the rise", Nature Climate Change, doi:10.1038/nclimate3079

http://www.nature.com/nclimate/journal/vaop/ncurrent/full/nclimate3079.html (http://www.nature.com/nclimate/journal/vaop/ncurrent/full/nclimate3079.html)

23. The linked reference indicates that the climate responses (climate sensitivities) projected by advanced climate models generally match observations when apple to apple comparisons are made.  This is a useful finding as advanced climate models generally indicate that climate sensitivity values are towards the high end of the IPCC climate sensitivity range:

Mark Richardson, Kevin Cowtan, Ed Hawkins & Martin B. Stolpe (2016), "Reconciled climate response estimates from climate models and the energy budget of Earth", Nature Climate Change, doi:10.1038/nclimate3066

http://www.nature.com/nclimate/journal/vaop/ncurrent/full/nclimate3066.html (http://www.nature.com/nclimate/journal/vaop/ncurrent/full/nclimate3066.html)

24. The linked reference discusses paleodata to indicate that climate sensitivity increased from 3.3 - 5.6 (mean of 4.45k) at the beginning of the PETM up to 3.7 - 6.5 K (mean of 5.1K) near the peak of the PETM; and that if we burn only the easily accessible carbon reserves then GMST could increase by about 10C.  I note these climate sensitivity values are much higher than those inherent in the CMIP5 projections:

Gary Shaffer, Matthew Huber, Roberto Rondanelli & Jens Olaf Pepke Pedersen (23 June 2016), "Deep-time evidence for climate sensitivity increase with warming", Geophysical Research Letters, DOI: 10.1002/2016GL069243

http://onlinelibrary.wiley.com/doi/10.1002/2016GL069243/full (http://onlinelibrary.wiley.com/doi/10.1002/2016GL069243/full)


25. The linked Reuters article notes that NASA reported that a new satellite-based method have located 39 unreported sources of anthropogenic emissions that, when accounted for, increase our previously estimated amount of sulfur dioxide by about 12 percent of all such anthropogenic emissions from 2005 to 2014.  This indicates that the CMIP5 projections also underestimated the impact of this negative forcing source; which raises the prospect that climate sensitivity (ECS) is likely higher than the CMIP5 models indicate, and the linked Zhai et al (2015) reference analyses of the CMIP3&5 results conclude that the ECS is likely 3.9C +/- 0.45C:

Chengxing Zhai, Jonathan H. Jiang & Hui Su (2015), "Long-term cloud change imprinted in seasonal cloud variation: More evidence of high climate sensitivity", Geophysical Research Letters, DOI: 10.1002/2015GL065911

http://in.reuters.com/article/us-nasa-pollution-idINKCN0YO1PW (http://in.reuters.com/article/us-nasa-pollution-idINKCN0YO1PW)

26. The linked reference uses an information-theoretic weighting of climate models by how well they reproduce the satellite measured deseasonlized covariance of shortwave cloud reflection, indicates a most likely value of ECS of 4.0C; which indicates that AR5 errs on the side of least drama:

Florent Brient & Tapio Schneider (2016), "Constraints on climate sensitivity from space-based measurements of low-cloud reflection", Journal of Climate, DOI: http://dx.doi.org/10.1175/JCLI-D-15-0897.1 (http://dx.doi.org/10.1175/JCLI-D-15-0897.1)


http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-15-0897.1 (http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-15-0897.1)


27. The linked article indicates that the contribution of sea-ice loss to Arctic Amplification is regulated by the PDO and that in positive PDO phases (like we are in now) there should be less Arctic Amplification.  Thus the fact that we are currently experiencing high Arctic Amplification during a period of highly positive PDO values gives cause for concern that climate sensitivity may be higher than considered by AR5:

James A. Screen & Jennifer A. Francis (2016), "Contribution of sea-ice loss to Arctic amplification is regulated by Pacific Ocean decadal variability", Nature Climate Change, DOI: 10.1038/nclimate3011


http://www.nature.com/nclimate/journal/vaop/ncurrent/full/nclimate3011.html (http://www.nature.com/nclimate/journal/vaop/ncurrent/full/nclimate3011.html)


28. The linked reference uses an information-theoretic weighting of climate models by how well they reproduce the satellite measured deseasonlized covariance of shortwave cloud reflection, indicates a most likely value of ECS of 4.0C.  As this satellite data is certainly biased by the recent acceleration of natural aerosol emissions associated with the increasing atmospheric CO2 concentration, the actually ECS is likely higher than 4.0C, as will become apparent if climate change reduces future plant activity.  Unfortunately, the envisioned upgrades to the Paris Pact do not have any contingency for addressing such high values (4 to 4.5C) of ECS (including accelerting NET):

Florent Brient & Tapio Schneider (2016), "Constraints on climate sensitivity from space-based measurements of low-cloud reflection", Journal of Climate, DOI: http://dx.doi.org/10.1175/JCLI-D-15-0897.1 (http://dx.doi.org/10.1175/JCLI-D-15-0897.1)


http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-15-0897.1 (http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-15-0897.1)

Best regards,
ASLR,

Edit: And for those who do not like to read, I provide the two attached images of high equilibrium climate sensitivity, with the first based on paleo data, and the second based on modern observations.
Title: Re: Validation of GCM Models
Post by: GeoffBeacon on March 20, 2017, 01:31:33 AM
Crandles

A different commentary on the paper
https://julesandjames.blogspot.co.uk/2016/11/apocalpyse-now.html (https://julesandjames.blogspot.co.uk/2016/11/apocalpyse-now.html)

The critical comments after the article you cite do weaken the effect of Friedrich et. al.'s Nonlinear climate sensitivity and its implications for future greenhouse warming (http://advances.sciencemag.org/content/2/11/e1501923) but I'm still worried about "missing feedbacks".

By how much are the CMIP5 models too optimistic because of "missing feedbacks"? Has anyone any good guesses?

I suppose we all worry about painting a picture of climate change that is so dark it becomes unbelievable to the public (Particularly if it is too pessimistic in the short term). On the other hand there is the worry about the delayers argument that climate change isn't so bad that we need to worry much about it.

The remaining carbon budget is a topics I can use in making representations to politicians, government bodies & etc. The status of the "missing feedbacks" has an important impact on this.

(EDIT: ALSR. Thanks for the homework. I was typing this at the time. It looks as if I will need time to digest it)

(EDIT2: Some students I know are organising a climate lecture in York, UK. They already have a prominent denier and are looking for a climate scientist to counter him. I suggested Kevin Anderson but I don't think he's replied yet. Any other suggestions? I'll see if I can get help with the homework!)
Title: Re: Validation of GCM Models
Post by: DrTskoul on March 20, 2017, 02:50:05 AM

(EDIT2: Some students I know are organising a climate lecture in York, UK. They already have a prominent denier and are looking for a climate scientist to counter him. I suggested Kevin Anderson but I don't think he's replied yet. Any other suggestions? I'll see if I can get help with the homework!)

What is the point of debating a Gish galloper?? It is almost futile unless the climate scientist is able for a Gish gallop of his own. Countering one by one the points of a Gish gallop is a waste of time....
Title: Re: Validation of GCM Models
Post by: jai mitchell on March 20, 2017, 05:15:50 AM

By how much are the CMIP5 models too optimistic because of "missing feedbacks"? Has anyone any good guesses?


https://twitter.com/RisetoClimate/status/839159599680761857
Title: Re: Validation of GCM Models
Post by: Pmt111500 on March 20, 2017, 05:22:26 AM

(EDIT2: Some students I know are organising a climate lecture in York, UK. They already have a prominent denier and are looking for a climate scientist to counter him. I suggested Kevin Anderson but I don't think he's replied yet. Any other suggestions? I'll see if I can get help with the homework!)

What is the point of debating a Gish galloper?? It is almost futile unless the climate scientist is able for a Gish gallop of his own. Countering one by one the points of a Gish gallop is a waste of time....
Basically it could become a general lecture on AGW with regular disturbances of the stupidest student. This should end up (again) by the stupidest student thinking his views are reinforced, and the listeners (hopefully) thinking this guy should be expelled. The denier will prepare with talking point memo that might have one or two hard to explain points of discussion and the scientist requiring more time than him which the inane idiot will take as break of debate rules. The rest of the memo contains shouts that interrupt explanations of inconvenient truths by the scientist thus disrupting the potential for learning for people who aren't already convinced that renewable(well ok, also nuclear, with way less highly active waste) energy is the only viable option for energy generation and transport if we as a species do not want sea levels of at least 9 meters higher and "who anyway cares what happens in 200 years, and is it 200 or 400 maybe and J.Hansen is a retired loonie."
Oh, the times when talking of car and especially driver performances at the latest wc rally have taken over the discussion at the local bar that only infrequents engineers. I for one was glad to hear about the start of electric drive-train manufacturing start at the local car builder. Oh yeah. Everybody though admits you cannot get as far in a day by electric cars than by internal combustion engine and leasing a car for the summer vacation trip is beyond them. Nice.

This is starting to become a rant so I stop. Thank you for listening and remember the disadvantages of electric rail/cars and the intermittency of wind/solar.
Title: Re: Validation of GCM Models
Post by: Pmt111500 on March 20, 2017, 05:33:35 AM
Oh, this was the 'validation of gcms'-thread. Sorry for the last one. Validation of gcms proceeds in many steps. Firstly, you gotta get the normal ghg-effect equations so correct that you get the surface temperature to rise from the non-ghg temperature of -17,5 c (or was it -18,5°C?) to rise to the observed preindustrial temperatures. There was a lengthy explanation of further validation steps somewhere, but not on computer so not going to find and summa4rize it right away.
Title: Re: Validation of GCM Models
Post by: Jim Hunt on March 20, 2017, 09:48:08 AM
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???????

Jim - I've recently spent many happy hours in the company of the deplorable denizens:

http://GreatWhiteCon.info/2017/03/that-deaf-dumb-and-blind-kid-sure-plays-a-mean-climateball/ (http://GreatWhiteCon.info/2017/03/that-deaf-dumb-and-blind-kid-sure-plays-a-mean-climateball/)

Your tactics are identical to theirs.

Please stop being so patronising. Stop the ad homs. State your case, if you have one.
Title: Re: Validation of GCM Models
Post by: Red on March 20, 2017, 11:33:49 AM
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???????

Jim - I've recently spent many happy hours in the company of the deplorable denizens:

http://GreatWhiteCon.info/2017/03/that-deaf-dumb-and-blind-kid-sure-plays-a-mean-climateball/ (http://GreatWhiteCon.info/2017/03/that-deaf-dumb-and-blind-kid-sure-plays-a-mean-climateball/)

Your tactics are identical to theirs.

Please stop being so patronising. Stop the ad homs. State your case, if you have one.
A layman's view.
Mr. Hunt after discovering your blog over the last few weeks I have to say your a dog for punishment. However I think we need more like you to chew up and spit out the crap of the denial industry. I love to read the past posts and the comment threads in particular. As with the ASIF the threads are always enlightening and great resources. I think I understand Mr. Williams point of view a little and think it may have more to do with predictions,(I could be way off base). Being very interested in CC for three decades or so and having most of my info coming from a list of authors to long to list it was always probably a decade old by the time it landed on the bookstore shelves. Then the IPCC reports started hitting the news in a big way at the turn of the century. Things like the Larsen B is fine for decades, gone two years later. The west Antarctic good for many decades to come and the east, millennium, both now looking unstable this century. 2c maybe this century now 4c-7c, 2c before 2050. SLR +/- 1 metre now maybe 4-5 metres. I see a lot of discussion about how they aren't really set up to do predictions. So why stick your neck out like that? I know at the regional level politicians want relevant info for planning, but if the bureaucrats at the top are dumbing down the science to render it void for that purpose it leaves the layperson thinking the science is wrong. When those of us paying attention see the next century away stuff going off every where now! I work in construction and the folks 40 to 60 years old see the changes and know something is changing for the worse. Those that look, think as I did, the models got it wrong. It's only after doing a lot of research on my own that I started to realize it was the politics that was causing the problem. I believe it to be unrealistic to think that a model that isn't robust enough to take in all the inputs,(if that's even possible), could be accurate enough for those sorts of demands. As I understand it, to have a processor big enough to run such a model, if it could even be constructed, would use most of our energy supply to run. Well we have that model now it just doesn't do print outs. We are the living print out. Point is I don't think so much that the models are wrong as incomplete. The ECS would seem to be pointing that out to our dismay. It may well be we need AI to run such a model and may even require it to build it. AI is in the foreseeable future, lets hope the ECS doesn't out run our ability to save ourselves as well as most of the flora and fauna on the planet.     
Title: Re: Validation of GCM Models
Post by: DrTskoul on March 20, 2017, 12:12:20 PM
You don't need AI to run any of those models. And a model is  by construct incomplete. It tries to uncover the major physics and processes and it can not account for all time scales... from the chemistry of the oceans to tectonics. The more complex the model the more difficult to parse the output and make correlations that are valuable and traces back to specific physical processes. We have the real life model as you said. We have managed to only make empirical connections e.g. with El Nino we have these expected weather patterns, which some times materialize and others not.

Without the reductive nature of models we would learn nothing about the underlying physical processes.
Title: Re: Validation of GCM Models
Post by: Jim Williams 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.
Title: Re: Validation of GCM Models
Post by: Neven on March 20, 2017, 01:05:36 PM
Now, that is the intended use of the ASIF.
Title: Re: Validation of GCM Models
Post by: TerryM on March 20, 2017, 05:56:09 PM
With all of the mentioning of works that point to an under evaluation of climate highs, are there any, other than the deniers, that feel that science is overstating the dangers going forward?


Thanks
Terry
Title: Re: Validation of GCM Models
Post by: Ninebelowzero on March 20, 2017, 06:42:21 PM
With all of the mentioning of works that point to an under evaluation of climate highs, are there any, other than the deniers, that feel that science is overstating the dangers going forward?


Thanks
Terry


In a humanocentric world when all the ice has gone will scientists be able to predict what the climate will be like not just in the Arctic but in highly populated regions elsewhere?.

Many fish species are already on the move. How many other species will become extinct?
Title: Re: Validation of GCM Models
Post by: AbruptSLR on March 20, 2017, 09:26:09 PM
Perhaps this thread should be renamed: "If Decision Makers Don't Care to Take Effective Action, Why Should Scientists Work to Refine Their Imperfect GCM Models?"
Title: Re: Validation of GCM Models
Post by: gerontocrat on March 20, 2017, 10:28:01 PM
Perhaps this thread should be renamed: "If Decision Makers Don't Care to Take Effective Action, Why Should Scientists Work to Refine Their Imperfect GCM Models?"

To bear witness. To leave a record.
Title: Re: Validation of GCM Models
Post by: AbruptSLR on March 20, 2017, 11:30:12 PM
Perhaps this thread should be renamed: "If Decision Makers Don't Care to Take Effective Action, Why Should Scientists Work to Refine Their Imperfect GCM Models?"

To bear witness. To leave a record.

As Neven pointed out, the ASIF is doing a good job of documenting the decline of the Arctic Sea Ice for the good of posterity.
Title: Re: Validation of GCM Models
Post by: Jim Hunt on March 21, 2017, 09:53:28 AM
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.
Title: Re: Validation of GCM Models
Post by: gerontocrat on March 21, 2017, 11:25:07 AM
Perhaps this thread should be renamed: "If Decision Makers Don't Care to Take Effective Action, Why Should Scientists Work to Refine Their Imperfect GCM Models?"

To bear witness. To leave a record.

As Neven pointed out, the ASIF is doing a good job of documenting the decline of the Arctic Sea Ice for the good of posterity.

Yes, and the need has never been greater with the prospect of climate science being cut off at the knees in the USA. But I am veering in the direction of policy, actions, solutions and can feel a moderator hovering over the delete button. So je suis fini.

Title: Re: Validation of GCM Models
Post by: Jim Williams 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.
Title: Re: Validation of GCM Models
Post by: Jim Hunt on March 21, 2017, 03:28:34 PM
I do not remember saying anything to you.

You have a remarkably short memory Jim. Allow me to refresh it (http://forum.arctic-sea-ice.net/index.php/topic,1922.msg106961.html#msg106961) for you:

Don't you understand English at all?
Title: Re: Validation of GCM Models
Post by: AbruptSLR on March 21, 2017, 03:42:07 PM
The link to the following April 2016 EGU General Assembly press conference 8 video clip roughly focused on the implications of the Paris Pact:

http://client.cntv.at/egu2016/press-conference-8 (http://client.cntv.at/egu2016/press-conference-8)

While the entire video is worth watching I provide the first attached image/screen shot showing DeConto & Pollard's (2016 EGU) projections of Antarctic contributions to changes in global mean sea level, GMSL, by the 2C (blue line), 2.7C (green line) and 3.6C (red line) forcing scenarios.  I believe that DeConto & Pollard's 2C scenario is not achievable in the real world, and that by 2100 the 2.7C and the 3.6C forcing scenario produce essentially the same amount of increase in GMSL.  Taken together with the more "Realistic" MIT analysis the DeConto & Pollard (2016 EGU) findings indicate it likely that the WAIS collapse will begin about 2050 following the current Paris Pact pledges (and also ignoring the increase in carbon emissions associated with increasing agricultural growth).

Also I note that the indicated DeConto & Pollard (2016 EGU) findings do not include Hansen et al (2016)'s ice-climate feedback and thus errs on the side of least drama (see the last two images).
Title: Re: Validation of GCM Models
Post by: Jim Williams on March 21, 2017, 03:58:29 PM
<snip; N.>
Title: Re: Validation of GCM Models
Post by: AbruptSLR on March 21, 2017, 04:24:11 PM
Maybe instead of measuring increases in GMSTA, we should be focused on monitoring biodiversity loss, as without sufficient biodiversity mankind's future is in doubt.

The linked article is entitled: “Ecological recession”: Researchers say biodiversity loss has hit critical threshold across the globe".  The article references both Newbold et. al. 2016 and Steffen et. al. (2015); both of which indicate that we are already exceeding some planetary boundaries, and will soon exceed others.

https://news.mongabay.com/2016/07/ecological-recession-researchers-ring-the-alarm-as-biodiversity-loss-hits-critical-threshold-across-the-globe/ (https://news.mongabay.com/2016/07/ecological-recession-researchers-ring-the-alarm-as-biodiversity-loss-hits-critical-threshold-across-the-globe/)

Extract: "An international team of researchers has concluded that biodiversity loss has become so severe and widespread that it could affect Earth’s ability to sustain human life.

- The researchers examined 2.38 million records of 39,123 terrestrial species collected at 18,659 sites around the world to model the impacts on biodiversity of land use and other pressures from human activities that cause habitat loss.

- They then estimated down to about the one-square-kilometer level the extent to which those pressures have caused changes in local biodiversity, as well as the spatial patterns of those changes.

- They found that, across nearly 60 percent of Earth’s land surface, biodiversity has declined beyond “safe” levels as defined by the planetary boundaries concept, which seeks to quantify the environmental limits within which human society can be considered sustainable.


See also:
Newbold, T., Hudson, L. N., Arnell, A. P., Contu, S., De Palma, A., Ferrier, S., … & Burton, V. J. (2016). Has land use pushed terrestrial biodiversity beyond the planetary boundary? A global assessment. Science, 353(6296), 288-291. doi:10.1126/science.aaf2201

http://science.sciencemag.org/content/353/6296/288 (http://science.sciencemag.org/content/353/6296/288)

Abstract
Land use and related pressures have reduced local terrestrial biodiversity, but it is unclear how the magnitude of change relates to the recently proposed planetary boundary (“safe limit”). We estimate that land use and related pressures have already reduced local biodiversity intactness—the average proportion of natural biodiversity remaining in local ecosystems—beyond its recently proposed planetary boundary across 58.1% of the world’s land surface, where 71.4% of the human population live. Biodiversity intactness within most biomes (especially grassland biomes), most biodiversity hotspots, and even some wilderness areas is inferred to be beyond the boundary. Such widespread transgression of safe limits suggests that biodiversity loss, if unchecked, will undermine efforts toward long-term sustainable development.

&

Steffen, W., Richardson, K., Rockström, J., Cornell, S. E., Fetzer, I., Bennett, E. M., … & Folke, C. (2015). Planetary boundaries: Guiding human development on a changing planet. Science, 347(6223). doi:10.1126/science.1259855

http://science.sciencemag.org/content/347/6223/1259855 (http://science.sciencemag.org/content/347/6223/1259855)
Title: Re: Validation of GCM Models
Post by: Jim Hunt on March 21, 2017, 07:31:43 PM
<snip; N.>

I'd love to see what's on your cutting room floor too Neven!  ;D
Title: Re: Validation of GCM Models
Post by: AbruptSLR on March 21, 2017, 07:55:11 PM
Perhaps this thread should be renamed: "If Decision Makers Don't Care to Take Effective Action, Why Should Scientists Work to Refine Their Imperfect GCM Models?"

To bear witness. To leave a record.

As Neven pointed out, the ASIF is doing a good job of documenting the decline of the Arctic Sea Ice for the good of posterity.

Yes, and the need has never been greater with the prospect of climate science being cut off at the knees in the USA. But I am veering in the direction of policy, actions, solutions and can feel a moderator hovering over the delete button. So je suis fini.

At least we will be able to tell future generations that we were fully aware of what was happening as we carefully documented the slide down to the collapse.
Title: Re: Validation of GCM Models
Post by: dnem on March 22, 2017, 02:59:14 PM
Obviously Jim's position is rather doctrinaire on this topic.  I don't know that much about GCMs but I tend to agree with him that at the end of the day, their utility in helping to understand the climate crisis, and respond to it, will be very limited.  For example, and yes I understand that the time scales are wrong, but the very warm non el nino driven global temps of the past two months are surprising, alarming and suggest that our overall understanding of the climate system is dangerously limited.

Have you all seen Orrin Pilkey's take on this general matter?

Useless Arithmetic
Why Environmental Scientists Can't Predict the Future
Orrin H. Pilkey and Linda Pilkey-Jarvis
Columbia University Press
https://cup.columbia.edu/book/useless-arithmetic/9780231132121
Title: Re: Validation of GCM Models
Post by: jai mitchell on March 22, 2017, 03:57:45 PM
FWIW I posted this paper on the 'science of aerosols' thread:

http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-15-0362.1 (http://journals.ametsoc.org/doi/abs/10.1175/JCLI-D-15-0362.1)

Indirect Aerosol Effect Increases CMIP5 Models’ Projected Arctic Warming

Petr Chylek et al.

Abstract
Phase 5 of the Coupled Model Intercomparison Project (CMIP5) climate models’ projections of the 2014–2100 Arctic warming under radiative forcing from representative concentration pathway 4.5 (RCP4.5) vary from 0.9° to 6.7°C. Climate models with or without a full indirect aerosol effect are both equally successful in reproducing the observed (1900–2014) Arctic warming and its trends. However, the 2014–2100 Arctic warming and the warming trends projected by models that include a full indirect aerosol effect (denoted here as AA models) are significantly higher (mean projected Arctic warming is about 1.5°C higher) than those projected by models without a full indirect aerosol effect (denoted here as NAA models). The suggestion is that, within models including full indirect aerosol effects, those projecting stronger future changes are not necessarily distinguishable historically because any stronger past warming may have been partially offset by stronger historical aerosol cooling. The CMIP5 models that include a full indirect aerosol effect follow an inverse radiative forcing to equilibrium climate sensitivity relationship, while models without it do not.
Title: Re: Validation of GCM Models
Post by: GeoffBeacon on March 22, 2017, 03:59:53 PM
ALSR

What's the origin/copyright of those images

Geoff
Title: Re: Validation of GCM Models
Post by: AbruptSLR on March 22, 2017, 04:18:57 PM
Obviously Jim's position is rather doctrinaire on this topic.  I don't know that much about GCMs but I tend to agree with him that at the end of the day, their utility in helping to understand the climate crisis, and respond to it, will be very limited.  For example, and yes I understand that the time scales are wrong, but the very warm non el nino driven global temps of the past two months are surprising, alarming and suggest that our overall understanding of the climate system is dangerously limited.

Have you all seen Orrin Pilkey's take on this general matter?

Useless Arithmetic
Why Environmental Scientists Can't Predict the Future
Orrin H. Pilkey and Linda Pilkey-Jarvis
Columbia University Press
https://cup.columbia.edu/book/useless-arithmetic/9780231132121 (https://cup.columbia.edu/book/useless-arithmetic/9780231132121)

The linked article indicates that the Trump Administration considers climate research a 'waste'.

https://www.washingtonpost.com/news/energy-environment/wp/2017/03/21/trumps-budget-slashes-climate-research-but-these-scientists-still-have-a-job-to-do/?tid=ss_tw&utm_term=.1d97ff9b7bdc (https://www.washingtonpost.com/news/energy-environment/wp/2017/03/21/trumps-budget-slashes-climate-research-but-these-scientists-still-have-a-job-to-do/?tid=ss_tw&utm_term=.1d97ff9b7bdc)

On April 22nd The March for Science will endeavor to teach the Trump Administration the errors of its thinking.
Title: Re: Validation of GCM Models
Post by: AbruptSLR on March 22, 2017, 04:33:38 PM
ALSR

What's the origin/copyright of those images

Geoff

Geoff,

I find almost all of the cartoon images that I post using GOOGLE, & thus I do not know the original source.  Therefore, if you want to retro search for the origins of the images you can use one of the following tools:

https://www.imageraider.com/ (https://www.imageraider.com/)
https://www.tineye.com/ (https://www.tineye.com/)
https://support.google.com/websearch/answer/1325808?hl=en (https://support.google.com/websearch/answer/1325808?hl=en)

Best,
ASLR
Title: Re: Validation of GCM Models
Post by: dnem on March 22, 2017, 04:59:57 PM
Have you all seen Orrin Pilkey's take on this general matter?

Useless Arithmetic
Why Environmental Scientists Can't Predict the Future
Orrin H. Pilkey and Linda Pilkey-Jarvis
Columbia University Press
https://cup.columbia.edu/book/useless-arithmetic/9780231132121 (https://cup.columbia.edu/book/useless-arithmetic/9780231132121)

The linked article indicates that the Trump Administration considers climate research a 'waste'.

https://www.washingtonpost.com/news/energy-environment/wp/2017/03/21/trumps-budget-slashes-climate-research-but-these-scientists-still-have-a-job-to-do/?tid=ss_tw&utm_term=.1d97ff9b7bdc (https://www.washingtonpost.com/news/energy-environment/wp/2017/03/21/trumps-budget-slashes-climate-research-but-these-scientists-still-have-a-job-to-do/?tid=ss_tw&utm_term=.1d97ff9b7bdc)

On April 22nd The March for Science will endeavor to teach the Trump Administration the errors of its thinking.

ASLR, not sure why you append this article to my post.  Orrin Pilkey, the author of the book is "Professor Emeritus of Earth and Ocean Sciences, Nicholas School of the Environment, at Duke University, and Founder and Director Emeritus of the Program for the Study of Developed Shorelines (PSDS) which is currently based at Western Carolina University."

I certainly did not intend my post to be anti-science! I'm a PhD ecologist and will be at the march.  But that does not mean that numerical modeling has an outstanding record of success.  There is a lot more to science than just modeling and I'm not sure why you are conflating the two as somehow inseparable.  Here is some more content from his Wikipedia page:

Pilkey began his career with the study of abyssal plains on the deep sea floor. As a result of the destruction of his parents' house in Waveland, Mississippi in Hurricane Camille (1969), he switched to the study of coasts. Pilkey's research centers on both basic and applied coastal geology, focusing primarily on barrier island coasts and the effects of shoreline stabilization and development, and sea-level rise. The PSDS has analyzed the numerical models used by coastal geologists and engineers to predict the movement of beach sand, especially in beach replenishment. In general, Pilkey argues that mathematical models cannot be used to accurately predict the behavior of beaches, although they can be useful if directional or orders-of-magnitude answers are sought. In the book, Useless Arithmetic, written with his daughter, Linda Pilkey-Jarvis, they argue that the outcome of natural processes in general cannot be accurately predicted by mathematical models.[1]
Title: Re: Validation of GCM Models
Post by: AbruptSLR on March 22, 2017, 05:49:24 PM

ASLR, not sure why you append this article to my post.  Orrin Pilkey, the author of the book is "Professor Emeritus of Earth and Ocean Sciences, Nicholas School of the Environment, at Duke University, and Founder and Director Emeritus of the Program for the Study of Developed Shorelines (PSDS) which is currently based at Western Carolina University."

I certainly did not intend my post to be anti-science! I'm a PhD ecologist and will be at the march.  But that does not mean that numerical modeling has an outstanding record of success.  There is a lot more to science than just modeling and I'm not sure why you are conflating the two as somehow inseparable.  Here is some more content from his Wikipedia page:

Pilkey began his career with the study of abyssal plains on the deep sea floor. As a result of the destruction of his parents' house in Waveland, Mississippi in Hurricane Camille (1969), he switched to the study of coasts. Pilkey's research centers on both basic and applied coastal geology, focusing primarily on barrier island coasts and the effects of shoreline stabilization and development, and sea-level rise. The PSDS has analyzed the numerical models used by coastal geologists and engineers to predict the movement of beach sand, especially in beach replenishment. In general, Pilkey argues that mathematical models cannot be used to accurately predict the behavior of beaches, although they can be useful if directional or orders-of-magnitude answers are sought. In the book, Useless Arithmetic, written with his daughter, Linda Pilkey-Jarvis, they argue that the outcome of natural processes in general cannot be accurately predicted by mathematical models.[1]
[/quote]

dnem,

I apologize for any confusion that my post may have contributed to (I believe I posted too quickly); as indeed Orrin Pilkey does fight against anti-science efforts.

Here is a link to an article co-authored by Orrin Pilkey were he fights against anti-science efforts in North Carolina:

https://www.earthmagazine.org/article/denying-sea-level-rise-how-100-centimeters-divided-state-north-carolina (https://www.earthmagazine.org/article/denying-sea-level-rise-how-100-centimeters-divided-state-north-carolina)

However, I do believe that this illustrates how complicated the challenge is of trying to motivate decision makers to follow the Precautionary Principle when denialist can just say that the model in question gives projections that are not sufficiently accurate, so they must use their own personal judgment to cancel funding to support such climate research as the current administration is doing.