By Steven Goddard
I recently had the opportunity to attend a meeting of some top weather modelers. Weather models differ from climate models in that they have to work and are verified every hour of every day around the planet. If a weather model is broken, it becomes obvious immediately. By contrast, climate modelers have the advantage that they will be long since retired when their predictions don’t come to pass.
Weather and climate models are at the core very similar, but climate models also consider additional parameters that vary over time, like atmospheric composition. Climate models iterate over very long time periods, and thus compound error. Weather modelers understand that 72 hours is about the limit which they can claim accuracy. Climate modelers on the other hand are happy to run simulations for decades (because they know that they will be retired and no one will remember what they said) and because it provides an excuse to sink money into really cool HPC (High Performance Computing) clusters.
But enough gossip. I learned a few very interesting things at this meeting.
1. Weather modelers consider the realm of climate calculation to be “months to seasons.” Not the 30 year minimum we hear quoted all the time by AGW groupies. That is why NOAA’s “Climate Prediction Center” generates their seasonal forecasts, rather than the National Weather Service.
2. The two most important boundary conditions (inputs) to seasonal forecasts are sea surface temperatures and soil moisture. No one has shown any skill at modeling either of those, so no surprise that The Met Office Seasonal forecasts were consistently wrong.
For example, just a few months ago the odds of La Niña were considered very low. Compare the December forecast with the May version. How quickly things change!
SST modeling capabilities are very limited, and as a result seasonal weather forecasts (climate) are little more than academic exercises.
Oh and by the way, Colorado will be exactly 8.72 degrees warmer in 100 years. But they can’t tell you what the temperature will be next week.
“If I don’t understand it, it must be simple.”
– Dilbert Principle
In the top picture, which boxer is weather and which one is climate? What do readers think?
R. Gates, you should listen to Bobbie Burns: “To see oursels as ithers see us!”
You claim that “no matter what facts are presented to them [skeptics – the only honest kind of scientists] because it is an emotional bond they have with their beliefs, not a rational one. I have no such attachment…”
Who are you trying to kid? You constantly call yourself a 75% climate alarmist [while heading a 2-car household], and pretend that you have an open mind??
Please.
Admit what you are: a CAGW advocate pushing an agenda.
And for my skeptical part, simply show me where the climate has exceeded its past parameters, and you will have a CAGW convert.
Word up.
carrot eater says:
July 1, 2010 at 1:42 pm
“Not once have you shown that you understand that weather prediction is an initial value problem, and climate is a boundary value problem.”
This is NOT true! Please have a look at the differential equations being solved. This idea that the solutions do not depend on the initial conditions is simply bogus and demonstrates a fundamental lack of understanding of mathematical physics…
Also, read this.
Having spent much time examining anomalies on 4,200 months of CET, it became apparent to me that the majority of the coldest winters, were soon followed by above normal temperatures, usually as early as April, and typically July at the latest. It is not very easy to identify many times where a significant number of years in succession have markedly both lower winter, and lower summer temperatures. The two clear examples are a run from the mid 1680`s to the late 1690`s (the worst of Maunder), and a few years around 1815. The observation of a none to clear climatic signiture of the late LIA in CET has also been noted here;
http://homepage.ntlworld.com/jdrake/Questioning_Climate/_sgg/m2_1.htm
The majority of the series would appear to consist of short term changes in temperature, showing far larger range in the winter months, and very little evidence for what is conventionally regarded as a climatic tendancy or trend/cycle, more like event clusters, a bunch of warm winters and then a bunch of cooler winters, to simplify.
This very useful resource shows the same patterns through the earlier parts of the LIA, in terms of hot years right next to very cold years, or cold winters followed by hot summers:
http://booty.org.uk/booty.weather/climate/histclimat.htm
It is very clear to me that what is regarded as weather, not only completely dominates climatic structure, but season by season, is what we really need to know about first, due the magnitude of natural variation.
On Canada Day nothing better than an Environment Canada gem:
“Asked if there may be a hot spell on the horizon, Jones said he couldn’t say other than noting mid-July to mid-August is typically the driest time of the year for Vancouver:
“Just ignore [the long-term forecast] because there’s nothing we can tell you with any reliability,” he said.”
Amaaaaazing!
This is what Kerry and Waxman said about GRACE. I’m surprised all the GRACE apologists here didn’t rush to Washington to straighten them out.
Paul Daniel Ash says: July 1, 2010 at 7:27 pm
“You could try reading about chaos, or you could just keep groping around in the dark. Your choice!”
When was the last time you took money from a automated teller machine?
Was it empty? Why did you choose that ATM at that time? Why not an hour later or the next day? Why did you not choose one a few blocks down the road? Somehow the machine seldom runs out of cash and yet the bank pays the minimum possible overnight interest of the unsold cash in the machine while spending a minimum amount in filling charges.
In that model you are the chaos. Unpredictable, yet I knew that you would be there 3 days before you did.
When was the last time you made a cell phone call? Did you get a signal? Was there space on the tower when you needed it? Did you notice when you were moved to another tower in anticipation of another call or that you were ok with the tower that you were on?
In that model you are the chaos. Unpredictable, yet I knew that you would be there 3 hours before you did.
Some models of systems must work with chaotic elements, like you.
I think I understand how to model a cyclical system with a large contingent of chaotic influences. Do you? Or do you just read about it?
At the risk of being accused of pedantry, I’ll point out that Cassandra was blessed with the gift of prophecy, and cursed so that her predictions, though correct, would not be believed. So I certainly hope that the doom-sayers are not Cassandras.
I wouldn’t be disappointed, though, if the not-believed part were accurate.
dr.bill says: July 1, 2010 at 12:28 pm
“…..But feel free to rave on.”
vukcevic: July 1, 2010 at 1:21 pm
If you are real Dr. (someone ?), then for the above choice of words, the real name rather than the ellipsis would be more appropriate, so readers can judge the real command of authority you articulate.
dr.bill says: July 1, 2010 at 2:02 pm
“Translate, please?”
No need doc. I also use Vuk etc. when frivolous…
CarrotEater declares: “Not once have you shown that you understand that weather prediction is an initial value problem, and climate is a boundary value problem.”
This primitive authoritarianism is really annoying. I am tired of repetition of this meaningless AGW gobbledygook.
There is no “climate boundary or initial or whatever problem”, there is only one coupled dynamical system that can be considered as two coupled boundary value problems, oceans and atmosphere, with non-trivial (and non-stationary) boundary conditions and with uncountable set of possible initial states (“values”) of the system. There is only one (and fully deterministic) evolution of these initial states called “weather”, which appears to be quite irregular and chaotic.
One can apply various spatio-temporal filters over these solutions and call them whatever you wish, “regional climate”, “global seasonal (or yearly) temperature”, whatever suite your needs. However, the science (classical mechanics) of condensed media has come to conclusion that averaged equations of this turbulent motion are not closed, and therefore no new physical abstraction can be identified (that can be called “climate”) and governed by some special physical equations. Therefore, one cannot “calculate climate” without calculating physical weather first.
This does not mean that the weather must be calculated precisely to reproduce every hurricane or location and time of every tornado in Texas. Since topological properties of phase flow on weather attractor are known to have hyperbolic qualities, the weather seems to be pretty ergodic, and therefore small computational imperfections should keep the [correctly designed] system on the attractor, such that statistically speaking the GCMs should be capable of predicting climate. The keyword here is “correctly designed”, especially with regard to slow-changing boundary conditions and long-distance weak interactions.
Cheers to audacious climate modelers – Al
Paul Daniel Ash
The IPCC also say:
http://www.ipcc.ch/ipccreports/tar/wg1/505.htm
“In sum, a strategy must recognise what is possible. In climate research and modelling, we should recognise that we are dealing with a coupled non-linear chaotic system, and therefore that the long-term prediction of future climate states is not possible. The most we can expect to achieve is the prediction of the probability distribution of the systems future possible states by the generation of ensembles of model solutions. This reduces climate change to the discernment of significant differences in the statistics of such ensembles. The generation of such model ensembles will require the dedication of greatly increased computer resources and the application of new methods of model diagnosis. Addressing adequately the statistical nature of climate is computationally intensive, but such statistical information is essential.”
The IPcc and Kevin Trenberth continually cite concerns over computer models of which clouds-amongst other factors-are a particular fly in the ointment.
That is not to say that such models are not interesting, but merely that the phrase ‘not possible’ should be a hint as to the degree of credence we should place on them
tonyb
IPCC climate modelling GIGO
Relative forcing
Solar irradiance — 0.12 W/ m sq , CO2 —- 1.66 W/ m sq, for CO2 10 x greater
http://www.ipcc.ch/graphics/syr/fig2-4.jpg
Models gives results
http://www.ipcc.ch/graphics/syr/fig2-5.jpg
Now interesting thing about it is: Observations are always in the middle of the modelled range. Smell of a ‘dead’ rat.
I suspect: Use observations, work backwards and calculate relative forcing then adjust the range to fit observations.
I suggest to the Core Writing Team of IPCC i.e. Pachauri, R.K. and Reisinger, A. (Eds.) to take a look at this:
http://www.vukcevic.talktalk.net/AMOFz.htm
No forcing, no back calculations and no fiddles here, just what natural system does, like it or not.
Steven:
“But the whole point of the climate models is to evaluate the feedback from changes to the environment. Feedback is calculated through iteration, and if the feedback assumptions are incorrect, the model output will become progressively divergent from reality. There is no magic averaging function which will come to the models’ rescue.”
That may be true, but it is not de facto true as you try to claim in this article–and this is my point of contention. Just because some of the dynamics of the system are chaotic does not mean all of the dynamics are. I have no problem with skepticism over the models (I myself am quite weary of them as well; I am an atmospheric scientist), but your particular skepticism is based on the faulty science. And when you purport to be a science blog, you lose credibility.
Re: your response to carrot eater
CE: “Not once have you shown that you understand that weather prediction is an initial value problem, and climate is a boundary value problem.”
SG: “If you have something specific to say technically, I’d like to hear it. But when people start quoting terminology they learned earlier in the day, it is pretty much of a turn off.”
Do you think that is a reasonable, professional response?
timheyes:
“I think you’ll find that January colder than July in the northern hemisphere due to Earth’s orbit around the Sun and the axial tilt of the Earth WRT the orbital plane.”
Exactly. And the dynamics of the Earth’s orientation relative to the Sun are well-understood and easy to predict long into the future.
Tonyb,
I’m glad at least someone else here gets that models are used to predict “the probability distribution of the system’s future possible states by the generation of ensembles of model solutions.” The highlighted words are important: using output from a range of different models – rather than relying on just one – to estimate the likely ranges of a host of variables. Very different than a specific forecast.
The idea that models are thought of as perfect predictors in part comes from the popular press, no doubt, who treat big computers as some sort of time machines. It’s also a useful straw man to some, obviously, as evidenced by this whole nonsense about “100%” and “exactly 8.72 degrees warmer.”
“By contrast, climate modelers have the advantage that they will be long since retired when their predictions don’t come to pass.”
=====
Ot long since retired when their predictions do come to pass.
Smokey says:
July 1, 2010 at 8:29 pm
R. Gates, you should listen to Bobbie Burns: “To see oursels as ithers see us!”
You claim that “no matter what facts are presented to them [skeptics – the only honest kind of scientists] because it is an emotional bond they have with their beliefs, not a rational one. I have no such attachment…”
Who are you trying to kid? You constantly call yourself a 75% climate alarmist [while heading a 2-car household], and pretend that you have an open mind??
Please.
Admit what you are: a CAGW advocate pushing an agenda.
And for my skeptical part, simply show me where the climate has exceeded its past parameters, and you will have a CAGW convert.
Word up.
_____________________
Actually Sparky, you once more really twist my words as I was quite clearly talking about the true believers on both side of the issue, “warmist” and “skeptic” alike. I may be on the side of believing the AGW is likely happening, but I’m hardly an alarmist nor do I put the “C” in front of my AGW beliefs.
I’m not out to convert anyone, but simply try to present alternative views to plainly wrong or completely cherry-picked data, though it may be hard for some so-called skeptics to imagine that there are those who think that AGW could be happening without being alarmist, wild-eyed radicals. True believers want to see the world in extreme terms, and in fact can ONLY see the world in extreme terms– everyone is a saint or a sinner, whereas in reality most people are neither.
I’ve noticed that most people’s perception this issue is pretty broadly colored by their cultural preconceptions.
Folks who dislike big business will see reports of potential consequences in the media and discard anything that doesn’t fit as misinformation paid for by Big Oil, calling for changes in the economy and Western lifestyle that suit their ideological preferences.
Similarly, people who tend to mistrust government and academia see any ambiguous or contradictory study as vindication of beliefs that AGW is mostly or entirely a sham foisted upon the public by cynical scientists and liberal ideologues, for grant money and to further a particular political agenda.
There are – of course – exceptions to the rule, but I’ve found the correspondence between climate change attitudes and cultural affinities to be very strong in almost every case.
“This idea that the solutions do not depend on the initial conditions is simply bogus and demonstrates a fundamental lack of understanding of mathematical physics…”
The solution does depend on the initial condition. That’s why you run the model several times at different initial conditions, to get an ensemble of results.
But given the same boundary conditions (the external forcings), the long term trends are going to be about the same in each case. It’s the short term and decadal wiggles that differ.
Same as my point with the sun. Crank up the sun by 20%, and I won’t know if it’s El Nino or La Nina in Jan 2100, but I know on average it’s going to warm up over time.
Hi Paul your 7.44
Is that your web site linked to from your name? Some interesting articles.
I partially agree with what you write above, but I think that those on the ‘other side’ completely fail to notice that there are some considerable differences between those you would put under the one generic term of ‘sceptic.”
I wrote the folowing comment to another warmist but think it is very relevant to your observations. Comment from my warmist friend first;
“My theory would be that nearly all sceptics, and I can’t see any exceptions on this blog, start off being sceptical, usually for political reasons, and any science they later bring into the argument is done to try to bolster their preconceived position.”
I disagree. Most disbelievers start off agreeing with the party line-that there is AGW-and only after looking at it properly do a proportion then realise all is not what it seems. They have looked at the facts and changed their minds, so how is that bolstering their pre conceived position?
I think what you have failed to appreciate is that there are two main types of ‘disbelievers’.
The first are ’sceptics’ who have thought deeply about it, read the papers and changed their original position based on actual facts and observations. With this group you consistently hugely overestimate the political aspect.
The second group are ‘deniers’ (lower case and non perjorative) who hate the govt, hate authority, believe they should be able to do whatever they want. AGW is just one of many things they automatically disbelieve because they think it is a govt attempt to control them. There is a political element here, but equally very many hate govt of any complexion.
This last group hate AGW because they believe it is being used as a tool of the govt to intrude in to their life. The latter would go on denying until their last breath- no matter the proof. The former are perfectly rational people and would look at the evidence presented to them, but based on the past performance of some of those involved in promoting AGW-and the exaggerated claims made-would want to delve behind the headlines before accepting anything as factual.
Your group also has similar schisms. The quote you are trotting out about Al Gore is replicated in numerous green blogs where the green believer has as much made up their mind as the ‘denier’. There was a prime example of that this morning from the latest climate group interviewed on the BBC who said they ‘just know’ that man is wrecking the planet.
When there are so many question marks about the reliability of data-sea level rise,arctic ice variation through the centuries,global temperatures to 1850, Ocean temperatures,Co2 levels, and so many unknown facets- such as the real effect of the sun, the PDO etc, it is supremely arrogant of anyone to believe that the science is settled.”
So Paul, I believe that there are two broad movements on my side, one more rational than the other and most of whom probably started off in your camp. Equally there are two broad movements on your side, of which only one is reasonably rational and the other who would believe anyting that fitted into their world view.
I have come to believe over the years that ‘our’ rational wing is somewhat larger than yours. 🙂
Best regards
Tonyb
From: Paul Daniel Ash on July 2, 2010 at 5:38 am
Major problem being, that might not be how “ensemble” is used.
From Zhang’s (and Lindsay’s) “Introduction” section on the “Seasonal Ensemble Forecasts of Arctic Sea Ice” page:
In the 2008 paper we find:
Same model, different input data. You can see what the output looks like in the 2008 SEARCH Sea Ice Outlook (Full Report tab), Figure 6. From the ensemble came a median map.
As you quoted, “…by the generation of ensembles of model solutions.” This is what Zhang does. What you interpreted: “The highlighted words are important: using output from a range of different models – rather than relying on just one – to estimate the likely ranges of a host of variables.” Sorry, but only one model could be used for an ensemble forecast. Thus the accuracy of the ensemble forecast is dependent on the accuracy of that single model.
Dan
I am not talking about chaos. If you have the wrong polarity on a deterministic factor like cloud feedback, the results will increasingly diverge from reality through each iteration.
For example, if your bank gives you -5% interest and you are expecting +5% interest, you may come up with different compounded numbers after a few years. ;^)
TonyB,
What you describe has been noted over and over here: readers regularly comment that they assumed at first that “global warming” was a problem — until they did a little investigating, and realized that the whole CAGW premise has no empirical, testable evidence supporting it.
Those who claim that scientific skepticism is ‘political’ suffer from psychological projection. They are hobbled by their political belief system, and they cannot accept that what skeptics are saying is: prove it. Or at least provide real world, verifiable evidence showing that an increase in a minor trace gas controls the planet’s temperature.
If the financial stakes weren’t so high, the self-serving clowns promoting the CO2=CAGW conjecture would be laughed off stage for being a crowd of pseudo-scientific Elmer Gantry clones.
I think what you have failed to appreciate is that there are two main types of ‘disbelievers’.
No, I allowed for that. I don’t have any way of knowing how large each group is, but I’m sure that the blind skeptics and blind believers well outweigh their counterparts when it comes to internet postings.
Or at least provide real world, verifiable evidence showing that an increase in a minor trace gas controls the planet’s temperature.
Smokey, you keep saying that over and over again, but you never indicate what it could possibly mean. What would this “real world, verifiable evidence” look like? Can we tag individual molecules of CO2 and measure the forcing of that molecule and no other? Obviously not. What, then, would constitute the evidence you claim to be searching for? Give an example, or let go of the talking point: you can’t look for something without any way to recognize when you’ve found it.
[REPLY – At a guess, I think perhaps he means something that would refute Lindzen’s study on radiative forcing observations. However, you may be correct about the blindness of most on both sides as expressed on the internet. (Not in this forum, of course!) ~ Evan]
Goddard:
If you have some feedback completely wrong or completely missing, then obviously yes, your projection of where things will be in the distant future will not be in the right ballpark.
If that’s the basis of the point you’re trying to make, you could have actually written that in the original post.
carrot eater says:
July 2, 2010 at 8:08 am
“The solution does depend on the initial condition. ”
Yes it does! The PDEs demand it :^)
“That’s why you run the model several times at different initial conditions, to get an ensemble of results.”
So the climate solutions don’t “forget” their initial conditions like some claim. Excellent! :^)
“But given the same boundary conditions (the external forcings), the long term trends are going to be about the same in each case. It’s the short term and decadal wiggles that differ.”
However, the problem is that the boundary conditions depend non-linearly on the evolving solution. And the external “forcings” are not known perfectly. In the end, the “trends” generated by these models are going to be highly dependent on the behavior of the submodels (which are themselves imperfect) and the prescribed forcings. By the way, if everyone uses the same forcings, do you think the trends will be similar?? …hmmmm…
All of this begs another question – if the short term climate solutions are not accurate, why run them with high resolution grids? For example:
http://www.hpcwire.com/offthewire/NASA-Center-for-Climate-Simulation-Debuts-Spring-2010-95542709.html
“With the new augmentations of Discover we probably have a 3 to 4x increase in the amount of work that we can push through the computer in a day,” Webster said. “You can run more simulations at the same resolutions you’ve had, but the thing that really excites us is that we can run much higher resolution simulations.”
By the way, the multi-million dollar “new augmentations” of the Discover computing facility (referred to above) were paid for by US government “stimulus” money…just in case anyone was wondering who’s getting the climate ca$h…