Raff,

And I won't argue that these ideas are untrue. But to conclude that they are true you need a model that incorporates the known information about clouds, water vapour and so on. You use that model to tell you what happens, as evidence.

That is arrant nonsense. You know this is nonsense, but you're hoping that by attrition, people will get fed up and leave you to state that as the final word on this discussion.

A model is someone expressing a formula which is an embodiment of a theory. Once you prove the theory - if you can - then you can say that the model is accurate. But the model is not proof on its own, anymore than the statement of any equation is.

If I write an equation : IQ(raff) = Lines Per Post(raff) x 2.5

...then I have a created a model. That model is not proof that your IQ is linked to the number of lines you post. It's a STATEMENT of my theory that your IQ is linked to the number of lines you post. If you're happy the existence of my
model is proof that your IQ is linked to the number of lines you post, then I'm delighted for you.

Meanwhile.. back in the real world.....

michael hart, I'm glad that you treat all economic models with such disdain. I take it then, that you have no opinion of the likely effect of taxing carbon emissions and therefore would not object to a carbon tax in principle.

Radical, are you a creationist? Are others here? Your questions are very odd - "how many insects are there that are significantly genetically different because of evolving to counter insecticides?" those which have developed resistance to insecticides. "Could it not be that these insects have not evolved, but have adapted?" If you get killed by an insecticide it is difficult then to adapt. If you don't get killed then either you are genetically different and not (or less) susceptible to the insecticide, in which case your genes have a survival advantage over your peers and survival of the fittest will favor you, or you just didn't get a high enough dose. In the latter case, to 'adapt' and thus avoid a futher dose means to have the inteligence to recognize and avoid the source of the toxin. "If evolution does not necessarily mean speciation, how can evolution be identified?" Look at the genome perhaps or just look at whether the insects now survive against an insecticide that originally was toxic.

TheBigYinJames, you are wrong. Models are not just formulae. We make models in our heads every time we imagine something. Rhoda thinking that extra heat produces extra evaporations and hence clouds and hence reflection of sunlight all forms a model based upon her understanding at some level of the physics if each of those steps. It might be correct. Or not. It will use simplifications because many of the parts, for example at molecular level, are irrelevant at the level of abstraction at which she is thinking. But it is a model despite not being quantified or calculated. She is modelling the atmosphere in her head and drawing conclusions from the model.

Raff " Models are not just formulae"

Err, what else could they be?

michael hart, I'm glad that you treat all economic models with such disdain. I take it then, that you have no opinion of the likely effect of taxing carbon emissions and therefore would not object to a carbon tax in principle.

Not all models are created equal, but a taxed person does not need a Met-Office sized computer to argue that a new tax will make them poorer.

RKS if all we ever saw was people who agreed with us we'd have nothing to say. While we wait for climate to make the next move, what else do we do?

And anyway, it's cheaper and less annoying than arguing with John Cleese.

Or MDGNN.

Sorry, Martin A, but I do not agree; there is a big difference between adaptation and evolution. As yet, for all human tinkering with the genomes of many species, no known evolution has occurred.

I think one of the common fallacies of evolution is that all the species present developed from fewer species in the past – e.g. all the present dog species and cat species evolved from a single common ancestor. What evidence is there of that? Have you heard of the fossil shales somewhere in Canada (can’t remember its name, sorry, and can’t be bothered looking for it) which contains a huge number of species – some utterly unrelated to any known present-day species, implying that there could have been as great a variety of species then as now? If so, why not have similar variety during most of the life of… er… life on this planet?

Now look what you’ve done! You have allowed this conversation to drift way off topic! So, while you are reading this, try and see through the rising red mist what sort of evidence models could provide, apart from whether the input in its creation were correct or not.

Radical so you really are a creationist! You are confusing the adaptation that an individual can achieve with genetic adaptation, known as evolution. I imagine you are just playing word games when you say, "no known evolution has occurred". Evolution happens everywhere and can be observed in a dish.

And the number of species that have existed in past aeons is thought to dwarf the number now. So what? That has no bearing on whether labradors are genetically different from poodles. They still interbreed because they have not diverged far enough (they still have the same number of chromosomes for example)

Evidence that all dogs evolved from a single common ancestor? Their mitochondrial DNA tells their maternal lineage and almost certainly gives evidence of common ancestry.

michael hart, "a taxed person does not need a Met-Office sized computer to argue that a new tax will make them poorer". Indeed, he may instead just trust the *evidence* from his *mental model* of how the economy works.

Raff

TheBigYinJames, you are wrong. Models are not just formulae. We make models in our heads every time we imagine something.

Raff, you may say I'm wrong, but unfortunately for you, that doesn't make it so.

You seem to think your sentence above delivers a killer blow to my argument, when in fact it agrees completely with what I have been saying all along, and flies in the face of what you have been saying. Formulae, models, ideas, thought experiments, descriptions. They are all the same thing - they are our brains abstracting the idea of a relationship between observable phenomenon. Whether that relationship is expressed mathematically, in lines of modelling code, or just as a vague bit of hand-waving, they are all models. I'm glad you now accept that there is nothing special about a climate model - in essence it is no different from a man in a pub saying he thinks mouthwash is linked to oral cancer - it is a proposed theoretical relationship which is there to be proved or disproved - the model does not constitute the evidence by itself.

I can tell from the way you argue, you're not from a STEM education, you seem more intrigued by trying to define language terms. In science, words mean very specific things, the meanings of which are not up for debate. Scientists don't spend a lot of time arguing about what a model is, or what a feedback is, or what an equation is. Everyone grounded in science knows what these terms mean, they are not philosophical entities there to be discussed and picked apart by arts grads on blogs.

Let me explain it a bit for you. You say a model is evidence. You are wrong. The comparison of the model output with reality is the evidence. For shorthand, people may say the 'model is proven', but what they actually mean is the underlying relationship expressed by the model has been proven. The model is a just a calculation tool used by the scientist to calculate the raw material (modelled output) which can be used later to produce evidence that the underlying theory is correct. But the important step is not the model itself, it's the comparison step.

When you say a model is evidence for a theory, it's as stupid as saying "the calculator is evidence that the theory is correct", or "my squared-paper jotter is evidence for the theory". A model is just a tool, which may indeed be useful on the journey towards evidence and proof, but it is NOT evidence itself.

I don't blame you for elevating climate models to such exalted status as some sort oracle, since it seems to happen all over climate science. Real science doesn't do this, the theory and then the experiment are the major celebrated milestones. When they fire up the Large Hadron Collider, they don't put out a press release to the world saying how the computer program they used to model the expected results is working fantastically. They say THIS is our theory we proposed, and THESE are the results from the experiment, and the latter proves the former. Why mention the workaday calculation programs?

The problem for climate science is it has no luxury of an earth-sized planet for experimentation. So it can really only posit theories, it can never prove them. Climate science never has 'proof', so they have invented the idea that models are evidence - for them that is the only evidence they will ever have, but they are not evidence in the proper scientific sense of the word. The idea that models now constitute evidence is an artefact of a science which can never have any of the real proof. Unfortunately, this doesn't make it so.

I hope this clears it up for you, raff. Perhaps you might like to take a primer in science, in order to familiarise yourself with the rigour in terminology that an education in its methods insists upon.

TBYJ so why will nobody accept the consequences of what you say, not even you?

I will accept that models produce no evidence if each of you admits without artifice that there is no evidence that any degree of warming will be beneficial and that people like Ridley and perhaps even our host are completely wrong to claim that it will be or to draw attention to model-based research that suggests it will; and that there is no evidence that taxing carbon emissions will cause great economic harm...

And explain these views frm Rhoda, without support from any sort of model:

-- when it gets hot the effect of H2O is to redistribute the energy faster (presumably that means faster than if there isn't any water).

-- cumulus clouds are negative feedback (presumably the suggestion is that warming produces more cumulus clouds and that these reflect sunlight etc).

Not that they are untrue. Just show that they are true without using any sort of model.

Raff,

You're making the mistake many wide-eyed have made here - that we here somehow speak as a monolithic opinion, and we all must back each other up or else we're all flawed. I haven't even read what Rhoda has said, and I don't feel compelled to justify or condemn it. She could be completely wrong for all I know, or she might have stumbled upon the solution to the entire mystery. We're all independent here, unlike "the team" we don't vet each other's comments for "on-message" before posting them. This means we don't always agree. Welcome to the real world, the tradition of real Science which tolerates co-existing theories, and not the stifled, political world of climate science.

As for using a model to prove or disprove what she says - no model will do that, for all the reasons I've already gone over. A model may demonstrate her idea simulated in action, but it can never prove it happens in the real world. Yes, you need a model on your journey towards evidence, I agree with you there. Models are essential in our understanding of physical phenomenon. But they are NOT evidence, they are tools we use to get to evidence. Evidence has to be - and always has been the bedrock of science - an empirical measurement of nature, to compare with our model.

Really raff, this point is not that difficult to understand. A model is a simulation. All it proves is the idea is feasible or possible. It can never EVER prove that is what actually occurs in nature. You do that by looking at nature itself, if nature is doing what your model predicted, then your theory/model may be correct. But the evidence is not the model, the evidence is the comparison. That model is only useful as long as it tracks reality.

This is not hard stuff, come on you can do it!

Raff, I don't think a model can prove that some warming will be net beneficial or that in the future everyone will be richer but you can't prove things will be worse either. We know that life is more than supportable under warmer temperatures and that current economic practices seem to be good for society and prosperity. What we know for certain is that at the moment we can't do without fossil fuels without massive hardship. We do not need models for that, there is proof out there already. That makes all models irrelevant. People will not embrace hardship without very good reasons. Those reasons do not yet exist. I do not need a model for that either, the daily actions of the public are proof enough.

Reality trumps models every time. Too many modellers (climate or economic) forget that.

Martin, I suspect the truth is more mundane.

raff, a debater, looks ahead chess-like at where the conversation will go.

If he admits models are just theories and real evidence comes from measuring nature, then he loses the argument, because nature is not cooperating.

So he must step back in the debating moves, and deny measuring nature is evidence at all, in order to head off this inexorable conclusion.

This leads him to the truly ridiculous debating strategy of claiming something ridiculous, such as models are evidence. For to do otherwise is to admit defeat one or two steps down the argument, he knows it, we know it.

TBYJ, I don't have any illusions about your views being all the same. But you are unanimous against me that models don't produce evidence. I expect you all to be consistent in that opinion.

Rhoda's points were as written above. No research is necessary to understand them, they are commonplace and trivial. That you refuse to consider how they can be shown to be true or false without reference to a model is unsurprising. You cannot, hence your reticence.

But you can accept the others, which follow directly from your position on models and evidence: that Ridley and Montford and others are wrong to use model output to claim warming is beneficial and that there is no evidence that taxing carbon emissions will cause great economic harm. Why won't you?

Martin A, you moved the goalposts. You suggest I or others think that "a model, ... can provide the same sort of evidence about the physical world that physical measurements and observations provide". Maybe you have somewhere, but I have not seen that said. And I have only said they provide evidence, unqualified.

"The idea that there can be "evidence" about things that are yet to happen is simply nonsense."

Here's a suggestion for you. Go down to the railway track and put your ear to the rail. If you hear the noise of an approaching train, don't worry, it cannot possibly be evidence that your head will soon be crushed if you don't move it.

raff

Here's a suggestion for you. Go down to the railway track and put your ear to the rail. If you hear the noise of an approaching train, don't worry, it cannot possibly be evidence that your head will soon be crushed if you don't move it.

That is yet again a prime demonstration that you don't understand what evidence is. I mean the word and concept of evidence. You seem to think evidence means "suggests an explanation" or '"is one of the characteristics of a possible explanation" or "means the most likely explanation is about to happen".

If you put your ear to the track and hear/feel a rumble. You seem to think that is "evidence" that a train will come and crush your head. It's not. You misunderstand what evidence is, we're getting to the nub here.

The rumble is a phenomenon. It could be caused by any number of sources. One of them is that a train is about to come and crush your head. One is that someone is drilling the track half a mile away.. Another is that the train has already passed. One is that there's an earthquake. Another is that you are imaging the vibration.

The hearing of the rumble itself is not evidence of any of those possible explanations.

The evidence is when the train comes by.

Do you get it now?

raff

But you can accept the others, which follow directly from your position on models and evidence: that Ridley and Montford and others are wrong to use model output to claim warming is beneficial and that there is no evidence that taxing carbon emissions will cause great economic harm. Why won't you?

I do, when it's pointed out to me.

If they are modelling and say their models prove something, then they are mistaken.

I have no idea if warming will be beneficial, and neither do they.

So yes, they are wrong too.

Raff

Here's a suggestion for you. Go down to the railway track and put your ear to the rail. If you hear the noise of an approaching train, don't worry, it cannot possibly be evidence that your head will soon be crushed if you don't move it.

Sorry Raff now you're getting very silly, that is not a model that is an experiment. Now the head-crushing may not happen if the train (assuming you;re talking about the noise from a train/locomotive) is actually moving away from you. A further period of observation will confirm the direction of travel. Equally likely on a Sunday is that what you can hear is the sound of engineering work, again observation will prove that your model of head being crushed by locomotive is about as good as the climate models under discussion. Real data trumps models everytime.

TBYJ
Sorry your response to the response to crass stupidity was quicker than mine, but I couldn't let that one pass. Previously I had been enjoying the exchange as a lurker.

Raff also misses the point that the vibrating tracks have been observed countless times and most often it's the sound of a train either coming or going. Climate models have no... err... track record. Albert Einstein is reported to have said: No amount of experimentation can ever prove me right; a single experiment can prove me wrong. So if you create a model that says rumbling tracks always means there's a train coming then you would be proved wrong. A wider model might conclude that pressing your ear to the rails is a dumb idea, especially if you don't know which might be electrified.