“We know the risks even if we cannot quantify them exectly. And we already know the solution - cutting CO2. If you admit there is a risk, why are you implaccably opposed to solution?” Raff.

But there are other risks both global and personal some of them are even more catastrophic than climate change could ever be. We can’t quantify them either but does it mean we should drop everything and concentrate on those problems? Do we start at the most catastrophic and work down?

If CAGW was to be unimaginably bad is there anything we should not do to prevent it? Mass genocide? Enforced poverty? Euthanasia for the over 50s? Turn pets into pâté? Legalise murder?

If you take any issue to the extreme you can turn it into something stupid. We mostly don’t say don’t study it. We don’t say do nothing but we do say do things that will benefit us any way, until we know how bad the problem is. Deliberately courting poverty won’t solve AGW. Wasting money on solutions that don’t work won’t reduce emissions. Making people live poorer lives when the evidence of catastrophe is weak will just generate resentment.

I suggest that all those who do believe it’s a problem put their hands in their own pockets and prove they mean what they say. Maybe their noble sacrifice will impress the rest of us.

Rhoda - my take is that he is trying to raise the precautionary principle (use of risk in his arguments) based on the premise that if models come up with a figure of 4C (his preferred number?) then we should take that number seriously because the models say so..

I don't know if that would extend as far as the hopelessly implausible 12C number that came out of Climate Prediction Net as an illustration of the silly figures that models are capable of producing. Or why we should take the 4C as more credible than for example the 2C or less that comes out of recent observational studies

Tiny, there are always other risks. They are strawmen conjured up by Lomborgs jumping out of haystacks worldwide to prevent any action. Do you think that fixing global problems is like putting your socks on - you have to finish one before you do the other, otherwise you fall over?

Rhoda, my summary is that many of the views held here are illogical. People cannot simultaneously believe that climate is affected by GHGs without admitting the chance of significant damaging change (and hence the need to study and address change, which means CO2 reductions, models and paleo studies). Your own position is no better in that it ignores reality - rising sea levels, air and ocean temperatures, acidifying oceans, shrinking ice sheets and glaciers, degrading permafrost, changing species distributions. But at least by denying reality you can be more logical in rejecting models and action. Yet strangely you don't reject all models. GCMs would be fine if they were 'good' GCMs. Yet you will not explain how you would judge a GCM to be good.

clivere, 4C was arbitrary (as I indicated).

Micky, I think the null hypothesis would be 1C change for doubled CO2. To suggest a null of no change implies that you have overturned a century of physics. You would need some good evidence to do that. Just saying I don't believe it (figuratively putting your fingers in your ears and shouting la, la, la) allows you, like Rhoda, to reject research and action without causing too much cognative dissonance, hence its popularity as an approach.

geronimo, go on, humor me. Why is it "outrageously, obviously, stupid" to question why a model of the *climate* should have no facility to forecast solar cycles, tectonic activity, social behavior (as opposed to assuming some typical values)?

Interesting that in the Raff scheme of things, studying GHGs involves 'CO2 reductions, models and paleo studies' but it just plain ignores measuring what is happening and providing experimental proof in the lab and the field.

I don't trust the GCMs. I've explained why. I have multiple problems with them and their promoters. I have stated those problems here and elsewhere with no reply. Now, I may be a mere Oxfordshire housewife and ignorant of science, but you'd think the questions I have posed could be easily answered.

And while I believe in GHGs, I do not believe it to have been proven that a marginal change in a minor GHG makes a lot of difference. I have pretty good reason not to believe that the positive feedbacks are dominant. I am bemused, not to say amazed, that anybody would think they were otherwise. Yet the models depend on them.

I don't trust the GCMs. Or the cliimate science community. Why do they need to cheat?

Raff " Do you think that fixing global problems is like putting your socks on - you have to finish one before you do the other, otherwise you fall over?" No, I don't, that was my point. We all put in as much money and effort we think each hazard requires. WE JUST DON'T SEE AGW AS LIKELY/DANGEROUS AS YOU DO. And given the global lack of interest, neither does the vast majority of people. What part of that can you not understand?

I could point to at least 4 diseases that have the capability with a few, quite possible, mutations that could wipe out between 20 and 99% of the population. These diseases could be here within hours of the key mutations. Do we run around and panic? Do we ban all contact with the areas where those disease are likely to emerge? No. We apply the cautions we think are sensible at the time. Only time will tell if we are correct.

I will say that if AGW is going to be catastrophic and rapid, nothing we are doing now is more than a sticking plaster. Those who claim to believe in it, are not doing the sorts of hard self assessment that would be necessary to drastically reduce CO2. Why would anyone listen to a bunch of part time believers?

raff:"geronimo, you claim that a model of the climate should be able to model solar cycles, tectonic activity, social behavior (emissions) and ocean cycles."

You're at it again, I have never made any comments about what a model of the climate should be able to model, so giving me a list you've made up is adding no weight to your arguments. I am commenting on their performance and its worth as input into the polictical debate. I did say in passing that they were trying to forecast the future using a chaotic system that would interact with two other chaotic systems but to make it clear as I don't seem to be getting through to you I DO NOT BELIEVE YOU CAN FORECAST THE FUTURE STATE OF A CHAOTIC SYSTEM USING MODELS. So why the hell would I be suggesting that the models can forecast volcanoes, tectonic activity and social behaviour. (BTW if you're not American or from other ex-colonies in the Anglosphere honour and behaviour have "u" in 'em).

GCMs, the models we're talking about specifially have seven sets of equations to solve these are:

Atmosphere
Ocean
Sea ice
Land surface
Marine biogeochemistry
Ice sheets
Coupling between the components - Earth system models.

As you would imagine given the novelty of most of these as scientific research there are huge known unknowns in each of these areas and consequently there cannot be a comprehensive set of equations defining them, and there probably won't be for the foreseeable future at least.

Aerosols are the knob they use to make their hindcasts fit the temperature. So if the observed temperature is too low the introduce negative forcings for hindcasts that keep the temperature as that shown by the GCMs as correct, but reduce the observed temperature with the introduction of more aerosols. It seems never to occur to them that the models might be the problem.

"Would its projections be fundamentally wrong if it failed to forecast these events." The answer to that is if that is what they were trying to do, and there projections were wrong, then yes they would be fundamentally wrong. I'm not sure what you're not understanding that about that. As it happens the models are forecasting temperatures and then from these temperatures "projecting" what climatic conditions would be like. They've got the temperatures wrong, all else fails after that.

"Those who claim to believe in it, are not doing the sorts of hard self assessment that would be necessary to drastically reduce CO2. Why would anyone listen to a bunch of part time believers?"

Tiny I often wonder why those lying awake worrying about the upcoming thermageddon haven't cottoned on to the fact that the people they look up to don't give a FF for carbon footprints and fly all over the world, some of them have bought beach front houses, while 100,000s of the descend up cities having conferences on climate change. It's a bit like watching those working class people voting Labour at every election while it's really obvious that the upper middle class types at the top of the Labour party have not the remotest empathy with them and wouldn't be seen dead with them except for a photo opportunity.

Breath of Fresh Air, there are various posited feedbacks and studies of sensitivity use these to estimate the response to CO2. The pdf of some estimated responses do I imagine include zero, as well as including values of several degrees. You don't get one tail (the zero) without the other (significantly positive). So no, you cannot believe negative feedbacks cancel CO2 except in the sense of believing in UFOs and fairys.

As far as reality, rising sea levels, air and ocean temperatures, acidifying oceans, shrinking ice sheets and glaciers, degrading permafrost, changing species distributions are it. A 17 year history picked explicitly to start in an exceptional El Nino year is not.

Rhoda, your problems with GCMs and their authors strike me as mere conspiracy theory. And your purported belief in GHGs is betrayed by your words: "a marginal change in a minor GHG makes". Conspiracy theory and denial of physics is all you have. I am disappointed. You seemed to offer more.

Tiny, your 4 disease may well be a threat. Do we address them with the necessary seriousness? If not it is hard to think you believe that is because we are so busy addressing CO2. As I said we could address CO2 and disease. Why don't we? Careful putting your socks on now...

geronimo, I'm not aware of models trying to forecast volcanos etc. So lets try again. Would a GCM's projections be fundamentally wrong if they were wrong because of factors it was not attempting to model (i.e. factors that are entered as averages because they cannot be forecast, such as volcanic activity, solar cycle intensity, aerosol levels and el Nino) but not wrong once those factors were corrected?

" Careful putting your socks on now..."

Raff, I think we've established that you're the one who's scared of stuff. The rest of us manage fine until people like you want us to be scared along with you. The medical world realises we can't stop the world while we deal with problems, no matter how potentially severe.

!geronimo, I'm not aware of models trying to forecast volcanos etc. So lets try again. Would a GCM's projections be fundamentally wrong if they were wrong because of factors it was not attempting to model (i.e. factors that are entered as averages because they cannot be forecast, such as volcanic activity, solar cycle intensity, aerosol levels and el Nino) but not wrong once those factors were corrected?"

That's a hypothetical question with a loaded answer. The short answer is that if you are going to put guesses into the models you should say so before you publish the results, not after when the results are shown to be wildly out of kilter with reality. You should read Feynman, old school scientist, who exhorts scientists to tell everything they know about their work even if it might upset their own pet theory. How many politicians do you think know that huge areas of the models are educated guesses? And what do you think their response would be if they found out.

To emphasise it for you it is not possible to forecast the future state of a coupled non-linear chaotic system.

If you want to play childish "what if" games to win arguments you should try someone else.

Conspiracy theory and denial of physics is all you have. - Raff

We've seen unequivocal evidence of cheating numerous times. No need for a conspiracy theory.

Asking for evidence and pointing out that none has been provided is hardly 'denial of physics'.

Micky, you are wrong. Noone "assumes convection for one thing has no effect". It is well known to have an effect. Refer to http://scienceofdoom.com/2014/06/21/radiative-atmospheres-with-no-convection/ for a discussion of a hypothetical radiation-only atmosphere without convection. It seems that not only are you discarding a century of physics, you don't know what you are discarding.

Tiny, you didn't comment - *do* you think we are not addressing the threats you perceive with the necessary seriousness *because* you believe we are so busy addressing CO2?

geronimo, it is not hypothetical it is the actual situation. Oh and I would be careful throwing "coupled non-linear chaotic systems" around too freely.

Green Sand, no you are mistaking evidence for proof. See the start of the thread.

splitpin, "unequivocal evidence of cheating", such as?

rhoda, you all know that some cheat... Is that a reference to the same "unequivocal evidence of cheating" from splitpin? What is the nature of this 'cheating' (strange word, like they are taking an exam or a shortcut in a race)?

Admissions of doubt? All the scientific discussions I've seen are couched in doubt, confidence intervals and so on. If any people are short on doubt it is those here (for example). People give me certainties - this is wrong, this is worse than useless, etc. I've tried to get some sort of probability distributions from you to indicate your levels of confidence in any particular idea but non has been forthcoming. You don't do uncertainty, you just know. Skeptic, heal thyself.

You asked about run away warming (although you caught yourself later) but that assumes that feedbacks are constant. They don't have to be. If warming causes ice loss, albedo change, increased absorbtion and more warming, that feedback will stop when there is no more ice. Similarly with permafrost loss - there is only so much permasfrost.

“*do* you think we are not addressing the threats you perceive with the necessary seriousness *because* you believe we are so busy addressing CO2?”

*Yes!!* The best way to improve the problems of disease, warfare, inequality, and countless other human conditions is to raise the standards of other countries to that of our own. Or more specifically, don't stop them from trying to achieve that for themselves. Consumerism is the key to our success. Consumerism, not oil.

Current policies to solve AGW promote the suppression of industrialisation for those countries. Ideas of sustainability favour people keeping backyard flocks rather than buying pre-packed birds from mass producers. Lack of prosperity and organised farming leads to the consumption of bush meat and unhygienic practices when preparing and eating food. People are most at risk from malaria because they have no homes with windows and ways of keeping cool other than letting in the night air and the mosquitoes. Women in industrialised societies can escape the tyrrany of forced marriage and pregnancy.

So *yes* our obsession with AGW is making other hazards more likely.