Kicking the Climate Change Cat Further Down the Road... 43

[ewh]

What is the reputation of the NIPCC (Nongovernmental International Panel on Climate Change, a organization of 50 "top" scientists) in the engineering community? I really don't know how reliable they are, but a study (Climate Change Reconsidered II) produced by them and published by the Heartland Institute (an organization which espouses other ideas I disagree with) claims to be "double peer reviewed" and presents a seemingly well-founded arguement that AGW is a political red herring.
I am not a climate scientist, but thought that this was a good example of one side of the differing dogmas surrounding the issue. Just how is a layman supposed to make sense of these opposing arguments?

http://climatechangereconsidered.org/

or the summary

http://heartland.org/media-library/pdfs/CCR-II/Summary-for-Policymakers.pdf

“Know the rules well, so you can break them effectively.”
-Dalai Lama XIV

 

[2dye4]

beej67

I think you broke some thermodynamics with that post.

Removal of vegetation -> "" While relatively carbon neutral, this reduces the energy 'removed' from the system by photosynthesis processes ""

This removed energy is only stored in carbon form for a very short time at the surface, it is released back immediately upon decay.

""IPCC have had the gall to claim that our current level of agriculture and urbanization has produced a net cooling effect on the earth""

Some have claimed that forests absorb more radiation and warm the land more than lighter colored farmland. No doubt urban areas capture more
heat. If forests capture more heat than open land then it is likely this effect has provided marginal cooling.

""Every jump a molecule of water makes on its path through the hydrologic cycle is a loss of energy in the energy balance of the planet,""

No I don't think so, energy cannot be created nor destroyed only transferred.

The cloud thing -- OK yup I buy that, but has anyone proven an increase in clouds is likely in the MMGW scenario??

The Earth does not cool or heat itself through vaporization or condensation of water, it is part of a closed system.

The direct heat produced by our energy usage activities is trivial compared to solar insolation. Not a factor at all.

""Mammals are very hot creatures by comparison to everything else on the planet"" Not relevant, again a closed system.

The Methane is a valid factor, however methane does not last long in the atmosphere before decomposing.

I count two valid issues in your post, both of which are considered in climate science.

So you are 0 for 12 issues that are valid and not considered in climate science.

 

[cranky108]

"methane does not last long in the atmosphere before decomposing" So why is the EPA trying to regulate it?
Follow the money.

 

[beej67]

Go back and review the 1st law of thermodynamics, 2dye4. I will admit I was a little sloppy with my words above, so lets be clear on the thermodynamic ramifications here.

If the earth is a closed system, and things requiring energy are happening in that system, then that energy cannot also be simultaneously encountered as heat. Think about how much kinetic energy is in convection in the atmosphere at any given moment, and then think about how much more kinetic energy there is if we get more hurricanes due to global warming. That kinetic energy must come from somewhere, and that "somewhere" is the same pot of energy that the "warming" comes from.

Think it through.

Removal of vegetation -> "" While relatively carbon neutral, this reduces the energy 'removed' from the system by photosynthesis processes ""

This removed energy is only stored in carbon form for a very short time at the surface, it is released back immediately upon decay.

The carbon is released back. All of those processes require energy while they're ongoing, and when those processes are eliminated from the closed system on a large scale, due to something like urbanization, they're no longer utilizing that energy. So the energy is experienced in some other form, such as heat.

Some have claimed that forests absorb more radiation and warm the land more than lighter colored farmland. No doubt urban areas capture more
heat. If forests capture more heat than open land then it is likely this effect has provided marginal cooling.

Go stand in a forest. Go stand in a corn field. Look at a forest on IR from space. Look at a corn field on IR from space. The mental gymnastics necessary to claim that corn fields cool the planet and forests warm it boggle my mind. Again, the main disconnect here is that the process of "being a forest" takes energy.

""Every jump a molecule of water makes on its path through the hydrologic cycle is a loss of energy in the energy balance of the planet,""

No I don't think so, energy cannot be created nor destroyed only transferred.

I phrased it poorly. Every jump a molecule of water makes in the hydrologic cycle requires energy, and so when more molecules are making those jumps, less of that energy is experienced in the system as heat.

The cloud thing -- OK yup I buy that, but has anyone proven an increase in clouds is likely in the MMGW scenario??

Dampening effect often ignored by the atmo chemists:
More heat = more water vapor = more clouds

Anthropogenic warming effect often ignored by the atmo chemists:
less plants = less transpiration = less clouds = more heat

The Methane is a valid factor, however methane does not last long in the atmosphere before decomposing.

And yet, we have this pesky hockey-stick graph above.



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[rconnor]

Beej67,

Much of what you said is correct in premise but dead-wrong in the conclusions you draw from it, while other statements are dead-wrong in both premise and conclusion.

Comments along the lines of cloud cover is an “energy balance term ignored by the climate scientists” is just so utterly wrong. Where do you get these conclusions from? Nothing is backed up by anything close to quantitative data or research. It sounds like you’re working off a lot of hunches, gut-feelings and eye-balling of graphs, all of which is in direct contrast to the conclusion of piles of peer-reviewed scientific studies.

Having said that, I’m in agreement with you in principle. Human actions, related to consumption (which, yes, is a function of population), are having major effects on the planet. The planet has never seen anything like us before as we’ve broken out of a lot of natural controls. We haven’t fully beat the “predator-prey” or “supply-demand” natural control but we have made ourselves very resilient to it. This has been accomplished largely through exploitation of natural and human resources. This exploitation is only going to get worse and worse if we want to continue down a consumption-centric, infinite growth paradigm.

I disagree with you, and the science does as well, that CO2 emissions are much less of a concern than those you brought up. However, they are part of the same problem that, largely, has the same solution. We need to curb consumption. I’m not willing to advocate for any population control measures (and most experts predict that the planet will do that for us at ~9 to 10 billion people). This leaves us with reducing the consumption/person. Improved efficiencies of technologies do that. Better city planning does that. And regulations or taxes on consumption do that.

All these solutions need to be either accompanied or preceded by massive cultural shifts. We need to erase our materialistic, consumption-is-success or consumption-is-status mentality. This is the antithesis of the current Western zeitgeist (a culture that the developing world would love to emulate) and therefore will not happen easily. I have my doubts over whether it can happen at all.

 

[2dye4]

beej67 I think you are still skirting the laws a bit.

""If the earth is a closed system""
Well it isn't or we wouldn't be alive here or having MMGW. The premise is that the heat flux in to the Earth from the sun
is balanced by the heat flux out of the Earth, but the steady state point is altered by greenhouse gasses.

From a thermodynamic perspective any alternative theories of the causes of the Earths temperature changing MUST
involve a mechanism to alter the net heat flux the Earth receives from the sun period...

Anyway some of your issues impact the albedo of the surface and have valid effects on the net heat flux.
And luckily these issues are easily resolved by analyzing the spectrum of solar energy absorbed.

Did you know plants are green because light of green color is utilized poorly by photosynthesis, plants reflect it away
and capture much of the other visible spectrum.

In summary heat is being exchanged on Earth in nearly an infinite number of ways, but if these process do not provide
a method to increase or decrease the rate of heat flux across the boundary that is the Earth system then they are not
an issue.

Give it a thought for a spell and you will see what I mean.

 

[GregLocock]

Re the ragbag comment. You have cherry picked phenomena that your hypothesis agree with, you have not listed those that do not, and you have not listed alternative explanations for the ones you have chosen. These are hallmarks of Cargo Cult Science. Feynman must be laughing his socks off.

You have also listed sub phenomena, ie those with obviously a common cause. If the globe is warming then absent other effects we would expect the sea level to rise for two reasons, and we would expect increased water vapour in the atmosphere and ice to melt.



Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

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[cranky108]

Still, if water vapor is increaseing, and it is raining less, than shoulden't the atomspheric pressure be increasing? Am I missing something?
I just need to know how this equasion balances?

 

[rb1957]

a warmer atmosphere can support a higher humidity ?

Quando Omni Flunkus Moritati

 

[TGS4]

rconnor - your knowledge and understand of numerical models (specifically control volume discretization schemes of the type used in GCMs) is fantastically underwhelming. And your appeal to authority consists of all of two articles that are 5+ years old, that address exactly nothing of my criticisms, is also telling. I understand that you desperately want to believe the catastrophe foretold by these models, but you probably would have better luck with the Oracle at Delphi.

Dr. Schmidt's article @ NASA tries to describe weather models as being initial value problems while climate models are boundary value problems. However, with climate being the time-integral of weather, I find that explanation to be lacking. Furthermore, the time-discretization described in the articles (20-30 min) implies an attempt to either simulate weather or the average of weather - both of which are doomed to failure on the order of about 144-150 time-steps (I'd have to find the article, but a recent Environment Canada article described the accuracy of long-term forecasts as being worse than chance 3+ days out).

From a numerical (control volume) modelling perspective, the mesh used is absurdly too coarse. It matters not the equations used to describe what happens INSIDE the control volume, although I doubt (but indeed do not know for certain) that the equations are much more than second-order - most likely they are linear. I have a difficult enough time generating a CFD model of natural convection up the outside of a heated cylinder with a similar number of grid points as used by these GCMs - the emergent phenomenon are extremely difficult to capture, let alone simulate.

To further describe my disdain for the discretization scheme, I offer the follow: I live in a location where the weather and climate can be vastly different in the span of hours and km. The difference between -20°C and 10°C is as small as whether the chinook wind stays aloft at 1000ft or drops to the surface; the difference between drought and flood is off by 1/4 mile (Dominion Land Survey distances were in miles...) from a strong thunderstorm; and winter temperatures of 10°C or -10°C depends on which side of the jetstream you are one - and can vary within 50km. Until we can figure out what causes and sustains weather events such as blocking highs, Omega-patterns, or even Rossby waves, any climate model is doomed to failure.

Finally, the outcomes of the GCMs predictions diverge from reality. Full stop - they made predictions and their predictions failed. The models are not validated in the non-tuned time, and therefore something (see above) is wrong. And this failure is on the global "parameters". On regional predictions, the modellers themselves admit to the models being pathetic (perhaps not the spin-doctor words they use, but that is the essence). And to that, I apply the legal phrase falsus in unum, falsus in omnia - if we can't even get the little things right, how do we have confidence in the whole? We can't; we shouldn't; and I, as one who is knowledgeable in the field, don't.

 

[rconnor]

GregLocock, cherry picked? What observed global climatic phenomena have I missed that are inconsistent with and unexplainable by the CO2 theory? (and it’s oh-so-rich that you would accuse me of cherry picking…)

My guess is that you have two: tropospheric hot spots and the “pause”. Neither are inconsistent with OR unexplainable by the CO2 theory and our understanding of the science. Both have been addressed at some length. Not including false counter-arguments isn’t being biased, it’s being rational. You’ve offered no defense in light of my debunking of these arguments. Either do so or stop regurgitating the same nonsense.

Let me do the leg work for you: WUWT had a “lengthy” list of “failed observations” the other day. Maybe you could link that? Although they are nothing but isolated, regional, seasonal predictions that has nothing to do with the Anthropogenic Global Climate Change Theory as a whole, so maybe you had the good sense not to include it because it was nonsense. There is a massive difference between short-term, spatially and temporally, predictions of seasonal weather and the predictions of long-term, wide scale changes in global climate. Again, none of them are inconsistent with and unexplainable by the CO2 theory and our understanding of the science. If you don’t understand the science then they might not be explainable but that matters not to me.

Or maybe you’ll bring up the 538 article by Pielke that says extreme weather events haven’t been increasing. This has been debunked over and over and over and over and over and [link ftp://texmex.mit.edu/pub/emanuel/PAPERS/Kunkel_etal_2013.pdf]over[/url] and again. Again, this is not inconsistent with and unexplainable by the CO2 theory and our understanding of the science. If you cherry pick the evidence and ignore the vast amounts of contradictory research then it might not be explainable but that matters not to me.

The main predictions of the CO2 theory are that increased levels of CO2 should cause:
- A decrease in outgoing longwave radiation along bands associated with CO2 – check
- An increase in downward radiation along bands associated with CO2 – check
Leading to…
- A radiative imbalance – check
Leading to…
- Increased energy accumulation within the system (OHC being the best measure) – check
- Cooling stratosphere - check
- Warmer surface temperatures – check
Leading to…
- Increased humidity (positive feedback to increase temperatures) – check
- Decreasing sea ice – check
- Rising sea level (partly due to decreasing sea ice, partly due to thermal expansion) – check

That’s not “ragbag”, that’s not “cherrying-picking”, that’s a scientific narrative. Again, without the use of models, you have a robust theory that provides an explanation for the physical mechanism behind the changes in our climate and agrees with empirical observations.

As to alternative explanations, I have described two – “it’s changed before” AKA “MAGIC!” and changes in solar activity, as these tend to be the most popular. The first is woefully unscientific and not a scientific counter-theory by any stretch. The second explanation has difficulty explaining many phenomena and has short term cycles that cannot explain long term trends. Furthermore, long-term solar trends have been on the way down since the 1940's but temperatures are much higher. Cosmic Rays and cloud seeding is another hypothesis but I’ve already linked about 6 papers that demonstrate that is not likely to have much effect on long term temperature trends. I’m not aware of any observed phenomenon that effects long term temperature trends that is better explained by a counter-hypothesis. I’d be opening to hearing such arguments.

You’ve started to talk about the Earth itself causing this warming trend. I don’t believe I’ve come across a paper that purports what you are talking about. Can you provide the link to one?

Also, beej67 has repeatedly been saying that “it’s anthropogenic but not caused by CO2”. Again, he has offered nothing to support this. It’s counter to vast amounts of peer-reviewed research. I, and the science, agree that humans have an effect on the climate outside of CO2 but I, and the science, observe that it has a much smaller effect (on global climate change) than CO2.

There’s also the null-hypothesis, which is favoured by some. There is a physical mechanism behind the wide scale, trending changes in our climate. If no theory can provide such an explanation, then you revert back to the null-hypothesis. However, the anthropogenic CO2 theory, as demonstrated by its agreement with observations, does provide a robust explanation for the physical mechanism behind the changes. It’s less important that no other hypothesis comes close to the explanatory power of the CO2 theory (although it’s true), the important part is that the CO2 theory is in such agreement with observations.

So you’re chastising me for not including counter-hypothesis that I’ve already demonstrated to have severe inconsistencies with observed changes? Should I also include the theory that aliens are driving climate change through epiphenomenal telepathy?

Regarding Feynman, one of us has repeatedly referred to empirical data, peer-reviewed research, provided detailed explanations of those studies and offered point-by-point rebuttals. The other has not used a single reference, has categorically rejected much of the information provided (admitting to not reading it) and picks-and-chooses which points he will harp on. One side is supported by the science, the other is supported by ideologically-driven self-reinforcing ignorance of the science. Feynman would certainly not approve of one of us.

 

[2dye4]

TGS4

""However, with climate being the time-integral of weather...""

I don't think this is true. Does 'climate' include the seasons ?? I think so
and this has nothing to do with weather.

And i still disagree that a fine grained fluid dynamic model is needed to predict the warming.
You did reply the last time we discussed this with something that sounded a touch convincing but
I forgot what it was.

Surely the warming inside a large greenhouse could be accurately calculated without modeling the
fluid dynamics of the interior.

And as a final note , the fluid dynamic solution is impossible to achieve for the Earth so
the requirement is tantamont to deciding to ignore the issue. Can't we infer some level of
warming will occur without the heat flow dynamics of the global winds ?? After all the heat
is captured it will 'be' somewhere so the average temp is increased which is what the discussion
metric is in the first place.

""Finally, the outcomes of the GCMs predictions diverge from reality. Full stop - they made predictions and their predictions failed""

Correction, they made predictions of the increase in temps per increase in CO2 concentrations.
To say the climate predictions were of absolute future results is ridiculous. This can not be
done even without any changes in the makeup of the atmosphere, so how can we expect climate
scientists to do it.
No the predictions are of the marginal temp increase given marginal CO2 increase. The temperature
estimates have always had a strong random component and always will, the problem breaks down
to probabilities.

The task is to in some way quantify the random process that is non CO2 forced portion of global
climate temperature to gauge what the likelihood of the current industrial era being manifested without
a CO2 forcing consideration.

 

[beej67]

a warmer atmosphere can support a higher humidity ?

Not really but sorta.

Two air parcels of different temperatures hold different amounts of water at the same percent relative humidity. That's why it's called "relative humidity." Humidity is the ratio of (the current partial pressure due to water vapor in a parcel) to (that parcel's equilibrium vapor pressure). The denominator varies with heat. When the heat goes up, the amount of water that can be stored in the atmosphere goes up, as does the amount of water actually evaporating, and the activity in the hydrologic cycle increases.

Truthfully, global warming might save mankind from the impending fresh water crisis, by creating more activity in the hydrologic cycle. Folks don't like to talk about that though.

Also, beej67 has repeatedly been saying that “it’s anthropogenic but not caused by CO2”. Again, he has offered nothing to support this. It’s counter to vast amounts of peer-reviewed research. I, and the science, agree that humans have an effect on the climate outside of CO2 but I, and the science, observe that it has a much smaller effect (on global climate change) than CO2.

Well I don't intend to quit my job and go do a PHD thesis on the subject just to win an internet argument, which is what it would take to defeat your Appeal To Authority. But I would like to respond to this. I didn't say it wasn't caused by CO2. I said some of it probably is, but nobody knows how much, because you cannot prove how much simply by calibrating a forecasting model to CO2 as "the science" has done. I have repeatedly shown why doing so is bad science. I could calibrate a forecasting model purely to methane and get similar results, because methane and CO2 have the same historical hockey stick. I could calibrate a forecasting model to square miles of urban land and get similar results, because square miles of urban land has the same hockey stick. I could calibrate a forecasting model to any other potential factor that changes climate and get similar results, because they all have the same hockey stick. The hockey stick is people.

My opinion is born out in the IPCC's actual research once you look at the numbers, because their own predictions vary so wildly on equilibrium climate sensitivity from one study to the next. The best ones in AR5 went down quite a bit, to about half the number the IPCC is still claiming.

And all of this doesn't even broach the fact that carbon trading won't fix anything. Let's presume, purely for the sake of argument, that the only thing in the whole world we're doing to to change the climate is burn oil and coal. If that's the case, the only way to stop affecting the climate is to completely stop burning oil and coal. And even if we did so, the globe would continue to warm at the rate it was before we started burning coal and oil instead of the rate it's warming now. It would still warm. It was warming before.

So what's the point of these carbon credits and carbon taxes again? Wouldn't it be smarter policy, and a better use of our collective resources, to start preparing ourselves for life on a warmer planet instead?

Hydrology, Drainage Analysis, Flood Studies, and Complex Stormwater Litigation for Atlanta and the South East -

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[zdas04]

"You don't need a fine grained model ..."?????? The current grid size is down to only slightly smaller than the state of Colorado. Remember that everything within a grid cube is treated as homogeneous. So I will average Raton, with Cortez, with Sterling, with Craig, with Vail, with Denver. Elevation spread from about 2500 ft to 12000 ft. Annual snowfall ranging from a few inches to dozens of feet. The results of this average are dominated by the heat island adjustments applied to Denver and Denver becomes the surrogate for the gridblock even though most of the forcing effects take place in the high mountains.

Then you look at the ocean grid blocks. The Japanese current is about 50 miles across. It dominates the climate of the Pacific rim. It is in a grid block nearly 300 miles across.

I have a CFD model of a single pressure vessel that uses 6 different grid sizes. It is a lot smaller than the earth, where we use one grid size.

David Simpson, PE
MuleShoe Engineering

Law is the common force organized to act as an obstacle of injustice Frédéric Bastiat

 

[TGS4]

And i still disagree that a fine grained fluid dynamic model is needed to predict the warming.

The warming predicated on a doubling of CO2 (given the logarithmic laboratory LWIR-spectral relationship between CO2 and temperature) is about 1°C. I don't think that you will find many credible skeptics who will disagree. However, 1°C doesn't get you to a catastrophe, so "feedbacks" are required. I can create a 1D equation predicting CO2 concentration and temperature with no need for and grid.

However, it is the feedbacks that need the GCM simulation. And they do a very poor job of it. Positive feedbacks are needed for catastrophe, so it is positive feedbacks that are programmed into the simulations. Clouds are very poorly treated by the current generation of GCMs, yet they constitute the primary nature of the feedbacks. And they are poorly treated because we don't really have a sufficient understanding of them - especially how they initiate, grow and finally how they disperse. And the GCMs that include coupled-ocean-atmosphere are worse because we so little data about the intricacies of currents (as indicated by zdas04) and deepwater processes.

You are indeed correct that the predictions of the GCMs are based on emission scenarios and cannot (nor ought not) predict such things as vulcanism. That said, the actual emission trajectory has been on the high-side of the "business-as-usual" case, which as generally the high-outliers in the model ensembles. Even the model runs simulating lower emission scenarios have over-predicted the atmospheric temperature rise (an atmospheric temperature rise hat has been stalled from anywhere from 9 to 17+ years, depending on which flawed metric you choose - the average of these say it is at least 13 years). So, the models fail. Simple.

To summarize:
- the GCMs are needed to directly calculate the feedbacks from CO2-increased LWIR.
- the physical processes w.r.t. those feedbacks are not well understood, hence a first-principles approach from the GCMs
- with this approach, the grid size is woefully inadequate, both from a computational perspective and from a experiential one
- when run beyond their tuning/training period, the models consistently over-predict temperatures

 

[2dye4]

Sunlight comes in through the clouds, warms the surface of the Earth, which tries to
radiate long wave IR back out into space. More CO2 lets less heat back out.

Why do you need to resolve where the wind is blowing and will be blowing in order to estimate the extra heat that will be trapped ??

I am not a climatologist, but it seems the scenario requiring a detailed and impossible fluid dynamic prediction
is not necessary. It is however convenient if you want to skew public opinion.

 

[2dye4]

""the GCMs are needed to directly calculate the feedbacks from CO2-increased LWIR""

Why are detailed fluid dynamic models needed for the feedbacks.

Why is it not possible to estimate cloud cover without knowing the intricate dynamics of how the wind will blow all over the planet.
Weather forecasters seem to be able to do it over the short term knowing only a few things like humidity and temperature.

We know of a positive feedback effect of snow cover which causes colder air temperatures which causes snow, no detailed fluid dyn models needed.
We know of a drought situation where the dryness causes higher temperatures which further eliminate moisture from a region, NFDMN (no fluid dny model needed )

We know the sun will cast a more overhead projection in the summer northern hemisphere and we predict it will be warmer as a result ( NFDMN )

Make the case for why whatever feedback could not just occur due to spatial averaged warmer air.

 

[TGS4]

Sunlight comes in through the clouds

Beyond a threshold of optical depth, no it doesn't. It increases the SWIR reflected back to space which doesn't heat the lower atmosphere or the earth. Clouds do, however, re-reflect outgoing LWIR and slow the cooling process.

A day is cooler when it is cloudy compared to when it is sunny. A night when it is cloudy is warmer compared to when it is clear.

Why do I care about winds? In one word: advection. Winds are the transport processes for heat. Winds (in the form of, for example Hadley Cells) advect heat from the tropics to the poles - cooling the tropics and warming the poles.

...it seems the scenario requiring a detailed and impossible fluid dynamic prediction is not necessary. It is however convenient if you want to skew public opinion.

I think that you are saying here that I have presented an impossible condition, which therefore makes the scientific case for "doing something" nigh impossible. Of course I could also read that to say that these GCMs, being completely inadequate to the task, are nevertheless convenient for skewing public opinion. I would tend to agree with both of those interpretations.

 

[zdas04]

It snowed in Farmington, NM yesterday with an ambient temperature of 51F. The snow stuck to grass and tree limbs until it melted. My wife says it was kind of pretty (I'm on another continent right not so I didn't see it).

The "Positive feedback loop" of "snow causes colder air and colder air causes snow" is just laughable. Even this "simple" system is too complex to describe without getting into the arithmetic of thermodynamics and fluid mechanics. Were it even true in the short term the world would be covered in glaciers.

Net positive feedback loops cannot be stable even in the short term. An avalanche is an example of a positive feedback loop--the falling mass accelerates which increases the momentum available to dislodge lower material which further increases momentum, etc. A few tens of seconds after the start of an avalanche it has reached a stable resting point and stops. If that were not true then then an avalanche that started at the top of the Andes would not stop until it reached the bottom of the Mariana's Trench. But the positive feedback loop is not stable and cannot exist for more than a few seconds. Snow/cold surface temps is anything but a positive feedback loop.

David Simpson, PE
MuleShoe Engineering

Law is the common force organized to act as an obstacle of injustice Frédéric Bastiat

 

[beej67]

Anyone read this yet?

http://ajae.oxfordjournals.org/content/early/2014/02/24/ajae.aau001.abstract

If so, I'm interested in hearing a summary.

Hydrology, Drainage Analysis, Flood Studies, and Complex Stormwater Litigation for Atlanta and the South East -

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[rconnor]

the outcomes of the GCMs predictions diverge from reality. Full stop - they made predictions and their predictions failed

This overly simplistic, under-informed statement is common amongst skeptics but needs unpacking. When do climate models “fail”? If climate models “fail”, does the theory fall apart?

----When Do Climate Models “Fail”----
This is a bit of a subjective question. An easy answer would be when observed temperature trends fall outside the predicted range of climate model runs. 1)Which temperature data set? 2) Which confidence range does it need to lie outside? 3) Which climate model runs? 4) For how long do they have to lie outside the confidence range? The answers are usually : 1) average of GISS, NCDC and CRU, 2)95%, and 3) average of all CMIP3 runs. 4) ranges from 1 day for “skeptics” to multiple years to a decade, let’s say 3 years.

So, let’s look to see if the average of the major temperature data sets lies outside the 95% confidence interval for the average of all model runs for at least 3 years. From AR5 SPM, Figure 1.4 (Dark Blue = GISS, “Mustard” = NOAA, Bright Green = CRU)
[image

http://m5.i.pbase.com/o9/10/152510/1/152647365.VGKk7kJX.IPCC_AR5_W_13jun7.PNG

]

“But…but…the leaked draft version of that graph is the right one! The IPCC tried to cover it up with the other one! You’re cherry-picking!” said the “Skeptics”.

Let’s make sure we understand why it was changed – it was wrong. In the leaked draft version, all series (models and observations) were aligned at 1990, a single year. Observations inherently include the random year-to-year fluctuations, whereas models do not as they are the average of numerous runs off numerous models. So to aligned to a single year, a hot one at that, makes the projections of the models appear hotter than they actually are. In other words, they took the projected trend from the models and attached it to the 1990 data point (which was hotter than the trend leading up to that). What should happen, and what did happen in the final report, is the projected trend line should be attached to the trend line leading up to 1990. That’s not “masking the truth”, that’s correcting a statistical error. If you’re curious, more info can be found here.

This is what the draft version did:
[image

http://tamino.files.wordpress.com/2012/12/compare1.jpg

]

And here is the same projected trends but, correctly, applied to the TREND leading up to 1990 (it looks almost identical to the IPCC final report):
[image

http://tamino.files.wordpress.com/2012/12/compare2.jpg

]

Or another way of looking at it, the trends since 1990:
[image

http://tamino.files.wordpress.com/2012/12/rates.jpg

]

So, NO, climate models have not “failed” to predict temperatures accurately.

----If Models “Fail” (which they haven’t), does the theory fall apart?----
We could stop here but let’s address the consolation argument, “well they may not have “failed” but they are certainly trending away from observations”. So let’s revise are second major question to, “If Models momentarily diverge from observations, does the theory fall apart?”. Again, we need to unpack this statement – 1) What is causing the divergence? 2) Is that error a crucial aspect of the theory? 3) If yes, is the divergence long enough and/or drastic enough to point to a serious flaw in the theory? We will take each question one at a time

1) What is Causing the Divergence?
We come back to the “pause”. If that pesky short-term memory issue is coming up again, please re-read any of my 13 previous posts on the subject. The basic answer is that we are in an negative PDO where La Nina events dominate, creating a short-term decrease in surface warming. Models do not attempt to accurately match ENSO periods with reality as ENSO is stochastic. However, the PDO is also cyclical and is purely about the short term storage and release of heat in the oceans – it cannot effect long-term trends.

Another stochastic element of climate that cannot be predicted is volcanoes. Again, volcanoes only have a short-term effect.

The last element that is difficult to predict is human actions. We appreciate this when discussing CO2 emissions and no one has an issue with their being different trends that represent different emission scenarios – we don’t expect the models to tell us what the emissions will be. However, few “skeptics” also realize this applies to other emissions such as aerosols. Recently, anthropogenic aerosol emissions have been higher than estimated, largely contributed to faster than expected growth in the developing world. More aerosols means less energy enters the troposphere which has caused incoming solar forcing to be less than estimated.

What do temperature trends vs model predictions look like when we account for these effects? The first image is the as-is model (CMIP5) vs observation trends (average of GISS, NOAA and CRU):
[image

http://s28.postimg.org/hvirsnjm5/Global.png

]

Now when we account for the La Nina dominated period by inputting the actual ENSO values into climate models, we get the following:
[image

http://s2.postimg.org/5t1caooe1/Global_El_Nino.png

]

When we update the aerosol and volcano values to match the actual observed trends, solar forcing gets adjusted and the trend looks like this:
[image

http://s23.postimg.org/vraz3r81n/Global_El_Nino_Solar.png

]

2) Is the Error (ENSO, Aerosols) a Crucial Aspect of the Theory?
Some of you I’m sure are saying “well you’ve just tweaked the models to get what you wanted!”. That is incorrect. All that was changed was:
- ENSO was set to match observations
- Volcano and aerosol (solar) values were set to match observations.

No one, including climates models, can predict when ENSO and volcano events will happen. Both of these are short term and have no effect on long-term trends. Aerosol adjustments came primarily from updated anthropogenic emission numbers (they were higher than previous projections). Again, models cannot predict emission trends from either CO2 or aerosols, you have to tell them what you think they’ll be and they tell you what temperature that will lead to.

So all that we have “tweaked” are aspect that are not predictable and, in the case of ENSO and volcanoes, have only short term effects. We have not adjusted anything related to CO2 sensitivity, cloud feedbacks, albedo effects, water vapour feedbacks, etc. The manner in which the models calculate all the interactions between CO2 and the environment, the various forcings and feedbacks and the way energy is moved around the system remain untouched – these are the “crucial” elements of the theory and the accuracy of climate models. Therefore, without making any adjustments to any crucial elements of our understanding of climate science, models are shown to be in excellent agreement with observations.

Beyond providing a definite NO to the question “Is the Error a Crucial Aspect of the Theory?”, we can also conclude that the crucial elements of the CO2 theory, when modeled, do an excellent job predicted temperature trends. The estimated effect of feedbacks and forcings are, firstly, very accurate and, secondly, well represented within climate models.

3) If Yes, Is the Divergence Long or Drastic Enough to Point to a Serious Flaw in the Theory?
Given that the answer is a clear NO to 2), this question doesn’t apply. Furthermore, reviewing the data actually says that the theory is even stronger than we thought.

I’d also like to illustrate just how spurious of an argument the “pause” is by showing the temperature trends of various sets vs a true pause (a flat line) vs a continued warming trend from 1997 on.
[image

http://s9.postimg.org/ag8qave2n/GISS_Trend.png

]
[image

http://s28.postimg.org/lymnu7k0d/Had_CRU_Trend.png

]

That’s your “pause” for ya.