Are you asking me to write out the interpretation of the evidence I see as a mathematical model
Not evidence. I want you to make a precise claim.
For example, “because CO2 is a greenhouse gas, and because there’s a lot more of it around than there used to be, that CO2 cascades into a warming event” is a not-quantified claim. It’s not precise enough to be falsifiable (which is how a lot of people like it, but that’s a tangent).
A quantified equivalent would be something along the lines of “We expect the increase in atmospheric CO2 from 300 to 400 ppmv to lead to the increase of the average global temperature by X degrees spread over the period of Z years so that we forecast the average temperature in the year YYYY as measured by a particular method M to be T with the standard error of E”.
Note that this is all claim, no evidence (and not a model, either).
Yes it is. For example, if CO2 concentrations and/or global temperatures went down by much more than the measurement uncertainties, the claim would be falsified.
For example, “because CO2 is a greenhouse gas, and because there’s a lot more of it around than there used to be, that CO2 cascades into a warming event” is a not-quantified claim.
The claim doesn’t mention any measurement uncertainties. Moreover, the actual claim is “CO2 cascades into a warming event” and, y’know, it’s just an event. Maybe it’s an event with a tiny magnitude, maybe another event happens which counterbalances the CO2 effect, maybe the event ends, who knows…
The claim doesn’t mention any measurement uncertainties.
That’s why I said “much more”. If I claimed “X is greater than Y” and it turned out that X = 15±1 and Y = 47±1, would my claim not be falsified because it didn’t mention measurement uncertainties?
The general test is whether the claim is precise enough to be falsifiable—is there an outcome (or a set of data, etc) which will unambiguously prove that claim to be wrong, with no wiggle room to back out?
And, by the way, IPCC reports are, of course, full of quantified claims like the one I mentioned. There might be concerns with data quality, model errors, overconfidence in the results, etc. etc, but the claims are well-quantified.
That is fair, so why was the claim that cars are a net positive not nearly as thoroughly scrutinized as my counterargument? I can’t help but notice some favoritism here...
Was such an analysis done? Recently? Is this such common knowledge that nobody bothered to refute it?
Edit: my imagination only stretches so far as to see climate change being the only heavy counterargument to the virtue of cars. Anything else seems relatively minor, i.e deaths from motor accidents, etc.
why was the claim that cars are a net positive not nearly as thoroughly scrutinized as my counterargument?
Because there is a significant prior to overcome. Whenever people get sufficiently wealthy, they start buying cars. Happened in the West, happened in China, Russia, India, etc. etc. Everywhere. And powers-that-be are fine with that. So to assert that cars are a net negative you need to assert that everyone is wrong.
Just out of curiosity, what is your stance on the impact of cars on climate change? And cars are too narrow, then what is your stance on fossil fuel consumptions and its impact on climate change?
You linked to parts of the debate I’ve never been exposed to, so I’m curious if there’s more to know.
Generally speaking, the issue of global warming is decomposable into several questions with potentially different answers. E.g.:
Have we observed general warming throughout the XX and early XXI century? That’s a question about facts and can be answered relatively easily.
Does emitting very large amounts of CO2 into the atmosphere affect climate? That’s a question about a scientific theory and by now it’s relatively uncontested as well (note: quantifying the impact of CO2 on climate is a different thing. For now the issue is whether such an impact exists).
Are there other factors affecting climate on decade- and century- scales? Also a question about scientific theories and again the accepted answer is “yes”, but quantifying the impact (or agreeing on a fixed set of such factors) is not so simple.
What do we expect the global temperatures to be in 20/50/100 years under certain assumptions about the rate of CO2 emissions? Ah, here we enter the realm of models and forecasts. Note: these are not facts. Also note that here the “complicated” part becomes “really complicated”. For myself, I’ll just point out that I distrust the confidence put by many people into these models and the forecasts they produce. By the way, there are a LOT of these models.
What consequences of our temperature forecasts do we anticipate? Forecasting these consequences is harder than forecasting temperatures, since these consequences are conditional on temperature forecasts. Some things here are not very controversial (it’s unlikely that glaciers will stop retreating), some are (will hurricanes become weaker? stronger? more frequent? Umm....)
What should we do in response to global warming? At this point we actually leave the realm of science and enter the world of “should”. For some reason many climate scientists decided that they are experts in economics and politics and so know what the response should be. Unfortunately for them, it’s not a scientific question. It’s a question of making a series of uncertain trade-offs where what you pick is largely decided by your values and your preferences. I expect the outcome to be as usual: “The strong do what they can and the weak suffer what they must”.
What inference are you expecting readers to draw from that?
Inferences I draw from it: 1. Looks like researchers are checking one another’s results, developing models that probe different features, improving models as time goes on, etc.; those are all good things. 2. It would be good to know how well these models agree with one another on what questions. I don’t know how well they do, but I’m pretty sure that if the answer were “they disagree wildly on central issues” then the denier/skeptic[1] camp would be shouting it from the rooftops. Unless, I guess, the disagreement were because some models predict much worse futures than currently expected. So my guess is that although there are such a lot of models, they pretty much all agree that e.g. under business-as-usual assumptions we can expect quite a lot more warming over the coming decades.
[1] I don’t know of any good terms that indicate without value judgement that a given person does or doesn’t broadly agree that global warming is real, substantially caused by human activities, and likely to continue in the future.
That there is no single forecast that “the science” converged on
I confess it never occurred to me that anyone would ever think such a thing. (Other than when reading what you wrote, when I thought “surely he can’t be attacking such a strawman”.)
I mean, I bet there are people who think that or say it. Probably when someone says “we expect 2 degrees of warming by such-and-such a date unless something changes radically” many naive listeners take it to mean that all models agree on exactly 2 degrees of warming by exactly that date. But people seriously claiming that all the models agree on a single forecast? Even halfway-clueful people seriously believing it? Really?
A nice example of a non-quantified claim
Do please show us all the quantified claims you have made about global warming, so that we can compare. (I can remember … precisely none, ever. But perhaps I just missed them.)
Not that I think there’s anything very bad about non-quantified claims—else I wouldn’t go on making them, just like everyone else does. I simply think you’re being disingenuous in complaining when other people make such claims, while avoiding making any definite claims to speak of yourself and leaving the ones you do make non-quantified. From the great-grandparent of this comment I quote: “relatively easily”, “relatively uncontested”, “really complicated”, “I distrust the confidence …”, “a LOT of these models”, “not very controversial”, (implicitly in the same sentence) “very controversial”.
But, since you ask: I think it is broadly agreed (among actual climate scientists) that business as usual will probably (let’s say p=0.75 or thereabouts) mean that by 2100 global mean surface temperature will be at least about 2 degrees C above what it was before 1900. (Relative to the same baseline, we’re currently somewhere around 0.9 degrees up from then.)
“Sceptic” implies value judgement? I thought being a sceptic was a good thing
I paraphrase: “How silly to suggest that ‘sceptic’ implies a value judgement. It implies a positive value judgement.”
Being a skeptic is a good thing. I was deliberately using one word that suggests a positive judgement (“skeptic”) alongside one that suggests a negative one (“denier”). Perhaps try reading what I write more charitably?
I confess it never occurred to me that anyone would ever think such a thing.
I recommend glancing at some popular press. There’s “scientific consensus”, dontcha know? No need to mention specific numbers, but all right-thinking men, err… persons know that Something Must Be Done. Think of the children!
Do please show us all the quantified claims you have made about global warming
Is this a competition?
I don’t feel the need to make quantified claims because I’m not asking anyone to reduce their carbon footprint or introduce carbon taxes, or destroy their incandescent bulbs, or tar-and-feather coal companies...
Let me quote you some Richard Feynman: “I have approximate answers and possible beliefs and different degrees of uncertainty about different things, but I am not absolutely sure of anything”.
Being a skeptic is a good thing
It is to me and, seems like, to you. I know people who think otherwise: a sceptic is a malcontent, a troublemaker who’s never satisfied, one who distrusts what honest people tell him.
I recommend glancing at some popular press. There’s “scientific consensus”, dontcha know?
Yeah, there’s all kinds of crap in the popular press. That’s why I generally don’t pay much attention to it. Anyway, what do the deficiencies of the popular press have to do with the discussion here?
Is this a competition?
No, it’s a demonstration of your insincerity.
I don’t feel the need to make quantified claims because I’m not [...]
Status quo bias.
In (implicitly) asking us not to put effort into reducing carbon footprints, introduce carbon taxes, etc., etc., you are asking us (or our descendants) to accept whatever consequences that may have for the future.
I fail to see why causing short-term inconvenience should require quantified claims, but not causing long-term possible disaster.
(I am all in favour of the attitude Feymnan describes. It is mine too. If there is any actual connection between that and our discussion, other than that you are turning on the applause lights, I fail to see it.)
Anyway, what do the deficiencies of the popular press have to do with the discussion here?
Because my original conversation was with a guy who, evidently, picked up some of his ideas about global warming from there.
In (implicitly) asking us not to put effort into reducing carbon footprints
LOL. I am also implicitly asking not to stop sex-slave trafficking, not to prevent starvation somewhere in Africa, and not to thwart child abuse. A right monster am I!
In any case, I could not fail to notice certain… rigidities in you mind with respect to certain topics. Perhaps it will be better if I tap out.
I could not fail to notice certain… rigidities in your mind
I’m sorry to hear that. I would gently suggest that you consider the possibility that the rigidity may not be where you think it is, but I doubt there’s much point.
They don’t, that’s something you train to do.
Why? Are you asking me to write out the interpretation of the evidence I see as a mathematical model instead of a sentence in English?
Not evidence. I want you to make a precise claim.
For example, “because CO2 is a greenhouse gas, and because there’s a lot more of it around than there used to be, that CO2 cascades into a warming event” is a not-quantified claim. It’s not precise enough to be falsifiable (which is how a lot of people like it, but that’s a tangent).
A quantified equivalent would be something along the lines of “We expect the increase in atmospheric CO2 from 300 to 400 ppmv to lead to the increase of the average global temperature by X degrees spread over the period of Z years so that we forecast the average temperature in the year YYYY as measured by a particular method M to be T with the standard error of E”.
Note that this is all claim, no evidence (and not a model, either).
Yes it is. For example, if CO2 concentrations and/or global temperatures went down by much more than the measurement uncertainties, the claim would be falsified.
I said:
The claim doesn’t mention any measurement uncertainties. Moreover, the actual claim is “CO2 cascades into a warming event” and, y’know, it’s just an event. Maybe it’s an event with a tiny magnitude, maybe another event happens which counterbalances the CO2 effect, maybe the event ends, who knows…
That’s why I said “much more”. If I claimed “X is greater than Y” and it turned out that X = 15±1 and Y = 47±1, would my claim not be falsified because it didn’t mention measurement uncertainties?
Well, at this point I’d concede its not easy to make a claim with standards fit for such an example.
I’ll see what I can do.
The general test is whether the claim is precise enough to be falsifiable—is there an outcome (or a set of data, etc) which will unambiguously prove that claim to be wrong, with no wiggle room to back out?
And, by the way, IPCC reports are, of course, full of quantified claims like the one I mentioned. There might be concerns with data quality, model errors, overconfidence in the results, etc. etc, but the claims are well-quantified.
That is fair, so why was the claim that cars are a net positive not nearly as thoroughly scrutinized as my counterargument? I can’t help but notice some favoritism here...
Was such an analysis done? Recently? Is this such common knowledge that nobody bothered to refute it?
Edit: my imagination only stretches so far as to see climate change being the only heavy counterargument to the virtue of cars. Anything else seems relatively minor, i.e deaths from motor accidents, etc.
Because there is a significant prior to overcome. Whenever people get sufficiently wealthy, they start buying cars. Happened in the West, happened in China, Russia, India, etc. etc. Everywhere. And powers-that-be are fine with that. So to assert that cars are a net negative you need to assert that everyone is wrong.
Just out of curiosity, what is your stance on the impact of cars on climate change? And cars are too narrow, then what is your stance on fossil fuel consumptions and its impact on climate change?
You linked to parts of the debate I’ve never been exposed to, so I’m curious if there’s more to know.
tl;dr It’s complicated :-)
Generally speaking, the issue of global warming is decomposable into several questions with potentially different answers. E.g.:
Have we observed general warming throughout the XX and early XXI century? That’s a question about facts and can be answered relatively easily.
Does emitting very large amounts of CO2 into the atmosphere affect climate? That’s a question about a scientific theory and by now it’s relatively uncontested as well (note: quantifying the impact of CO2 on climate is a different thing. For now the issue is whether such an impact exists).
Are there other factors affecting climate on decade- and century- scales? Also a question about scientific theories and again the accepted answer is “yes”, but quantifying the impact (or agreeing on a fixed set of such factors) is not so simple.
What do we expect the global temperatures to be in 20/50/100 years under certain assumptions about the rate of CO2 emissions? Ah, here we enter the realm of models and forecasts. Note: these are not facts. Also note that here the “complicated” part becomes “really complicated”. For myself, I’ll just point out that I distrust the confidence put by many people into these models and the forecasts they produce. By the way, there are a LOT of these models.
What consequences of our temperature forecasts do we anticipate? Forecasting these consequences is harder than forecasting temperatures, since these consequences are conditional on temperature forecasts. Some things here are not very controversial (it’s unlikely that glaciers will stop retreating), some are (will hurricanes become weaker? stronger? more frequent? Umm....)
What should we do in response to global warming? At this point we actually leave the realm of science and enter the world of “should”. For some reason many climate scientists decided that they are experts in economics and politics and so know what the response should be. Unfortunately for them, it’s not a scientific question. It’s a question of making a series of uncertain trade-offs where what you pick is largely decided by your values and your preferences. I expect the outcome to be as usual: “The strong do what they can and the weak suffer what they must”.
What inference are you expecting readers to draw from that?
Inferences I draw from it: 1. Looks like researchers are checking one another’s results, developing models that probe different features, improving models as time goes on, etc.; those are all good things. 2. It would be good to know how well these models agree with one another on what questions. I don’t know how well they do, but I’m pretty sure that if the answer were “they disagree wildly on central issues” then the denier/skeptic[1] camp would be shouting it from the rooftops. Unless, I guess, the disagreement were because some models predict much worse futures than currently expected. So my guess is that although there are such a lot of models, they pretty much all agree that e.g. under business-as-usual assumptions we can expect quite a lot more warming over the coming decades.
[1] I don’t know of any good terms that indicate without value judgement that a given person does or doesn’t broadly agree that global warming is real, substantially caused by human activities, and likely to continue in the future.
That there is no single forecast that “the science” converged on and everyone is in agreement about what will happen.
If you’re curious, IPCC reports will provide you with lots of data.
A nice example of a non-quantified claim :-P
“Sceptic” implies value judgement? I thought being a sceptic was a good thing, certainly better than being credulous or gullible.
I confess it never occurred to me that anyone would ever think such a thing. (Other than when reading what you wrote, when I thought “surely he can’t be attacking such a strawman”.)
I mean, I bet there are people who think that or say it. Probably when someone says “we expect 2 degrees of warming by such-and-such a date unless something changes radically” many naive listeners take it to mean that all models agree on exactly 2 degrees of warming by exactly that date. But people seriously claiming that all the models agree on a single forecast? Even halfway-clueful people seriously believing it? Really?
Do please show us all the quantified claims you have made about global warming, so that we can compare. (I can remember … precisely none, ever. But perhaps I just missed them.)
Not that I think there’s anything very bad about non-quantified claims—else I wouldn’t go on making them, just like everyone else does. I simply think you’re being disingenuous in complaining when other people make such claims, while avoiding making any definite claims to speak of yourself and leaving the ones you do make non-quantified. From the great-grandparent of this comment I quote: “relatively easily”, “relatively uncontested”, “really complicated”, “I distrust the confidence …”, “a LOT of these models”, “not very controversial”, (implicitly in the same sentence) “very controversial”.
But, since you ask: I think it is broadly agreed (among actual climate scientists) that business as usual will probably (let’s say p=0.75 or thereabouts) mean that by 2100 global mean surface temperature will be at least about 2 degrees C above what it was before 1900. (Relative to the same baseline, we’re currently somewhere around 0.9 degrees up from then.)
I paraphrase: “How silly to suggest that ‘sceptic’ implies a value judgement. It implies a positive value judgement.”
Being a skeptic is a good thing. I was deliberately using one word that suggests a positive judgement (“skeptic”) alongside one that suggests a negative one (“denier”). Perhaps try reading what I write more charitably?
I recommend glancing at some popular press. There’s “scientific consensus”, dontcha know? No need to mention specific numbers, but all right-thinking men, err… persons know that Something Must Be Done. Think of the children!
Is this a competition?
I don’t feel the need to make quantified claims because I’m not asking anyone to reduce their carbon footprint or introduce carbon taxes, or destroy their incandescent bulbs, or tar-and-feather coal companies...
Let me quote you some Richard Feynman: “I have approximate answers and possible beliefs and different degrees of uncertainty about different things, but I am not absolutely sure of anything”.
It is to me and, seems like, to you. I know people who think otherwise: a sceptic is a malcontent, a troublemaker who’s never satisfied, one who distrusts what honest people tell him.
Yeah, there’s all kinds of crap in the popular press. That’s why I generally don’t pay much attention to it. Anyway, what do the deficiencies of the popular press have to do with the discussion here?
No, it’s a demonstration of your insincerity.
Status quo bias.
In (implicitly) asking us not to put effort into reducing carbon footprints, introduce carbon taxes, etc., etc., you are asking us (or our descendants) to accept whatever consequences that may have for the future.
I fail to see why causing short-term inconvenience should require quantified claims, but not causing long-term possible disaster.
(I am all in favour of the attitude Feymnan describes. It is mine too. If there is any actual connection between that and our discussion, other than that you are turning on the applause lights, I fail to see it.)
Sure. So what?
Because my original conversation was with a guy who, evidently, picked up some of his ideas about global warming from there.
LOL. I am also implicitly asking not to stop sex-slave trafficking, not to prevent starvation somewhere in Africa, and not to thwart child abuse. A right monster am I!
In any case, I could not fail to notice certain… rigidities in you mind with respect to certain topics. Perhaps it will be better if I tap out.
Er, no.
I’m sorry to hear that. I would gently suggest that you consider the possibility that the rigidity may not be where you think it is, but I doubt there’s much point.