Even if you grant that global warming is real that doesn’t mean that there also isn’t a lot of misinformation on the global warming side.
If I quiz a random number of liberal on the truth as the truth has been found by the IPCC, there are many issues where the liberals are likely saying that specific scenarios are more likely than the IPCC assumes.
there are many issues where the liberals are likely saying that specific scenarios are more likely than the IPCC assumes.
Could be. As I’ve said elsewhere in the thread, I think the relevant question is not “is there misinformation on both sides?” (the answer to that is likely to be yes on almost any question) but “how do the quantity and severity of misinformation differ between sides?”. My impression is that it’s not at all symmetrical, but of course I might think that even if it were (it’s much easier to spot misinformation when you disagree strongly with it). Do you know of any nonpartisan studies of this?
There was a letter by Nobel Laureates that suggested the probability of global warming is in the same class as evolution.
Given the probability I have in my mind for evolution, that’s off more orders of magnitude from the IPCC number than the positions of global warming skeptics.
Do you know of any nonpartisan studies of this?
Who would have to fund a study like this to be nonparitsan?
My impression is that it’s not at all symmetrical, but of course I might think that even if it were
How do you make that judgment? Did you read the IPCC report to have the ground truth for various claims? The great thing in the report is that it has probability categories for it’s various claims.
In reading most of the claims that the IPCC report makes about global warming are a lot less than 99% certain. Media reports generally have a hard time reasoning about claims with probability 80% or 90%.
a letter [...] that suggested the probability of global warming is in the same class as evolution [...] more orders of magnitude from the IPCC number than the positions of global warming skeptics.
I can only guess what letter you have in mind; perhaps this one? (Some of its signatories are Nobel laureates; most aren’t.) I’ll assume that’s the one; let me know if I’m wrong.
It doesn’t mention probability at all. The way in which it suggests global warming is in the same class as evolution is this:
But when some conclusions have been thoroughly and deeply tested, questioned, and examined, they gain the status of “well-established theories” and are often spoken of as “facts”.
For instance, there is compelling scientific evidence that [here they list the age of the earth, the Big Bang, and evolution]. Even as they are overwhelmingly accepted by the scientific community, fame still awaits anyone who could show these theories to be wrong. Climate change now falls into this category: there is compelling, comprehensive, and consistent objective evidence that humans are changing the climate in ways that threaten our societies and the ecosystems on which we depend.
They don’t claim that the probabilities are the same. Only that in all these cases the probability is high enough to justify saying that this is a thing that’s been scientifically established.
Who would have to fund a study like this to be nonpartisan?
I don’t know. Probably best not the fossil fuel industry. Probably best not any environmentalist organization. I think claims of bias on the part of government and academia are severely exaggerated, but maybe best to avoid those if only for the sake of appearances. A more pressing question, actually, is who would have to do it to be nonpartisan. You want people with demonstrated expertise, but the way you demonstrate expertise is by publishing things and as soon as anyone publishes anything related to climate change they will be labelled a partisan by people who disagree with what they wrote.
I don’t have a good answer to this.
How do you make that judgement? Did you read the IPCC report [...] most of the claims that the IPCC report makes about global warming are a lot less than 99% certain.
It’s not a judgement; my use of the rather noncommital word “impression” was deliberate. I make it by looking at what I see said about climate change, comparing it informally with what I think I know about climate change, and considering the consequences. It’s not the result of any sort of statistical study, hence my deliberately noncommittal language. I have read chunks of the IPCC report but not the whole thing. I agree that it’s good that they talk about probabilities. The terms they attach actual numerical probabilities to are used for future events; they usually don’t give any numerical assessment of probability (nor any verbal assessment signifying a numerical assessment) for statements about the present and past, so I don’t see any way to tell whether they regard those as “a lot less than 99% certain”. They say “Where appropriate, findings are also formulated as statements of fact without using uncertainty qualifiers”, which I take to mean that when they do that they mean there’s no uncertainty to speak of.
Here are a few extracts from the AR5 “synthesis report”.
Warming of the climate system is unequivocal [...] it is virtually certain [GJM: this is their term for >99%] that globally the troposphere has warmed and the lower stratosphere has cooled since the mid-20th century [...] It is virtually certain that the upper ocean (0-700m) warmed from 1971 to 2010 [...] Human influence [...] is extremely likely [GJM this is their term for 95-100%] to have been the dominant cause of the observed warming since the mid-20th century.
The key “headline” claims that distinguish the “global warming” from “not global warming” positions are “virtually certain”; attribution to human activities is “extremely likely” (and I have the strong impression that they are being deliberately overcautious about this one; note, e.g., that they say the best estimates for how much warming known human activity should have caused and the best estimates for how much warming there has actually been are pretty much equal).
I would judge the chances that evolution is incorrect by lower than 10^{-6}.
When the IPCC uses 10^{-2} as the category for global warming that off by many orders of magnitude.
A person who would believe that the chances of human-caused global warming are 10% would be nearer at the truth than a person who think that it’s in the same category as evolution.
and I have the strong impression that they are being deliberately overcautious
Basically given the information to which you have been exposed you have a strong impression that the IPCC is making a mistake in the direction that would align with your politics.
The outside view suggests that most of the time experts are a bit overconfident. The replication crisis suggests that scientists are often overconfident. With climate science we are speaking about a domain that doesn’t even have access to running real controlled experiments to verify important beliefs. That makes me doubt the idea that IPCC are underconfident.
If those IPCC scientists are that good at not being overconfident, why don’t we tell the psychologists to listen to them to deal with their replication crisis?
There are some contexts in which the difference between 99.999% and 99.9% is about the same as the difference between 10% and 90%. However, I do not think this is one of them. I repeat: the letter you are talking about did not say anything about probabilities; it said “some scientific theories have a shedload of evidence and are well enough established that we can reasonably call them facts; here are some familiar examples; well, global warming is also in that category”.
I think it’s probably 100x more certain that the earth is more than a few thousands of years old than that our universe began with a big bang ~14Gya. Does that mean the people who wrote that letter were wrong to group those together? Nope; all that matters is that both are in the “firmly enough established” category. So, they suggest (and I agree), is global warming.
(Not every detail of global warming. Not any specific claim about what the global mean surface temperature will be in 50 years’ time. But the broad outline.)
The outside view suggests that most of the time experts are a bit overconfident.
The outside view suggests to me that much of the time experts are horribly overconfident, and some of the time they are distinctly underconfident (at least in what they say). The picture doesn’t look to me much like one of consistent slight overconfidence at all.
If those IPCC scientists are that good at not being overconfident, why don’t we tell the psychologists to listen to them to deal with their replication crisis?
Hey, psychologists! Go read the IPCC reports, and follow their example!
There you go. I did. It won’t actually do any good, because the problem isn’t that no one has ever told psychologists to be cautious and avoid overconfidence. And that’s the answer to your question “why don’t we …”, and you will notice that it has nothing to do with the people who wrote the IPCC being overconfident.
the problem isn’t that no one has ever told psychologists to be cautious and avoid overconfidence.
The problem is probably that psychologists afterwards always nod their heads and say: “uhm, uhm, that’s interesting… please tell me more about your feelings of anxiety.”
There are some contexts in which the difference between 99.999% and 99.9% is about the same as the difference between 10% and 90%.
It’s not 99.9% in the IPCC report.
Events that happen with 0.005 probability are worth planning for when they have high impacts. We care about asteroid defense when that probability is much lower.
Humanity has a good chance of getting destroyed in this century if decision makers treat 0.001 the same way as 0.0000000001.
The outside view suggests to me that much of the time experts are horribly overconfident, and some of the time they are distinctly underconfident (at least in what they say)
In what examples are are experts underconfident when they give 0.9 or 0.95 probabilities of an event happening.
I wasn’t trying to suggest it was; my apologies for (evidently) being insufficiently clear.
Events that happen with 0.005 probability are worth planning for when they have high impacts.
Yup, strongly agreed. But here the low-probability events we’re talking about here are things like “it turns out global warming wasn’t a big deal after all”. It would be sad to have spent a lot of money trying to reduce carbon dioxide emissions in that case, but it wouldn’t be much like (e.g.) being hit by an asteroid.
In what examples are experts underconfident when they give 0.9 or 0.95 probabilities of an event happening
I don’t have examples to hand, I’m afraid (other than the IPCC example we’re discussing here, though actually all we know there is that their probability estimate is somewhere between 0.95 and 1, and is probably below 0.99 since they didn’t choose to say “virtually certain”. (Only “probably” because when they list what the terms mean they say 95-100% and not 95-99% for “extremely likely”, and the best explanation I can see for that is that they are reserving the right to say “extremely likely” rather than “virtually certain” sometimes even though they think the actual probability is over 99%. This is one reason why I suspect them of understating their certainty on purpose: they seem to have gone out of their way to provide themselves with a way to do that.)
Even if you grant that global warming is real that doesn’t mean that there also isn’t a lot of misinformation on the global warming side.
If I quiz a random number of liberal on the truth as the truth has been found by the IPCC, there are many issues where the liberals are likely saying that specific scenarios are more likely than the IPCC assumes.
Could be. As I’ve said elsewhere in the thread, I think the relevant question is not “is there misinformation on both sides?” (the answer to that is likely to be yes on almost any question) but “how do the quantity and severity of misinformation differ between sides?”. My impression is that it’s not at all symmetrical, but of course I might think that even if it were (it’s much easier to spot misinformation when you disagree strongly with it). Do you know of any nonpartisan studies of this?
There was a letter by Nobel Laureates that suggested the probability of global warming is in the same class as evolution.
Given the probability I have in my mind for evolution, that’s off more orders of magnitude from the IPCC number than the positions of global warming skeptics.
Who would have to fund a study like this to be nonparitsan?
How do you make that judgment? Did you read the IPCC report to have the ground truth for various claims? The great thing in the report is that it has probability categories for it’s various claims.
In reading most of the claims that the IPCC report makes about global warming are a lot less than 99% certain. Media reports generally have a hard time reasoning about claims with probability 80% or 90%.
I can only guess what letter you have in mind; perhaps this one? (Some of its signatories are Nobel laureates; most aren’t.) I’ll assume that’s the one; let me know if I’m wrong.
It doesn’t mention probability at all. The way in which it suggests global warming is in the same class as evolution is this:
They don’t claim that the probabilities are the same. Only that in all these cases the probability is high enough to justify saying that this is a thing that’s been scientifically established.
I don’t know. Probably best not the fossil fuel industry. Probably best not any environmentalist organization. I think claims of bias on the part of government and academia are severely exaggerated, but maybe best to avoid those if only for the sake of appearances. A more pressing question, actually, is who would have to do it to be nonpartisan. You want people with demonstrated expertise, but the way you demonstrate expertise is by publishing things and as soon as anyone publishes anything related to climate change they will be labelled a partisan by people who disagree with what they wrote.
I don’t have a good answer to this.
It’s not a judgement; my use of the rather noncommital word “impression” was deliberate. I make it by looking at what I see said about climate change, comparing it informally with what I think I know about climate change, and considering the consequences. It’s not the result of any sort of statistical study, hence my deliberately noncommittal language. I have read chunks of the IPCC report but not the whole thing. I agree that it’s good that they talk about probabilities. The terms they attach actual numerical probabilities to are used for future events; they usually don’t give any numerical assessment of probability (nor any verbal assessment signifying a numerical assessment) for statements about the present and past, so I don’t see any way to tell whether they regard those as “a lot less than 99% certain”. They say “Where appropriate, findings are also formulated as statements of fact without using uncertainty qualifiers”, which I take to mean that when they do that they mean there’s no uncertainty to speak of.
Here are a few extracts from the AR5 “synthesis report”.
The key “headline” claims that distinguish the “global warming” from “not global warming” positions are “virtually certain”; attribution to human activities is “extremely likely” (and I have the strong impression that they are being deliberately overcautious about this one; note, e.g., that they say the best estimates for how much warming known human activity should have caused and the best estimates for how much warming there has actually been are pretty much equal).
I would judge the chances that evolution is incorrect by lower than 10^{-6}.
When the IPCC uses 10^{-2} as the category for global warming that off by many orders of magnitude.
A person who would believe that the chances of human-caused global warming are 10% would be nearer at the truth than a person who think that it’s in the same category as evolution.
Basically given the information to which you have been exposed you have a strong impression that the IPCC is making a mistake in the direction that would align with your politics.
The outside view suggests that most of the time experts are a bit overconfident. The replication crisis suggests that scientists are often overconfident. With climate science we are speaking about a domain that doesn’t even have access to running real controlled experiments to verify important beliefs. That makes me doubt the idea that IPCC are underconfident.
If those IPCC scientists are that good at not being overconfident, why don’t we tell the psychologists to listen to them to deal with their replication crisis?
There are some contexts in which the difference between 99.999% and 99.9% is about the same as the difference between 10% and 90%. However, I do not think this is one of them. I repeat: the letter you are talking about did not say anything about probabilities; it said “some scientific theories have a shedload of evidence and are well enough established that we can reasonably call them facts; here are some familiar examples; well, global warming is also in that category”.
I think it’s probably 100x more certain that the earth is more than a few thousands of years old than that our universe began with a big bang ~14Gya. Does that mean the people who wrote that letter were wrong to group those together? Nope; all that matters is that both are in the “firmly enough established” category. So, they suggest (and I agree), is global warming.
(Not every detail of global warming. Not any specific claim about what the global mean surface temperature will be in 50 years’ time. But the broad outline.)
The outside view suggests to me that much of the time experts are horribly overconfident, and some of the time they are distinctly underconfident (at least in what they say). The picture doesn’t look to me much like one of consistent slight overconfidence at all.
Hey, psychologists! Go read the IPCC reports, and follow their example!
There you go. I did. It won’t actually do any good, because the problem isn’t that no one has ever told psychologists to be cautious and avoid overconfidence. And that’s the answer to your question “why don’t we …”, and you will notice that it has nothing to do with the people who wrote the IPCC being overconfident.
The problem is probably that psychologists afterwards always nod their heads and say: “uhm, uhm, that’s interesting… please tell me more about your feelings of anxiety.”
:D
It’s not 99.9% in the IPCC report.
Events that happen with 0.005 probability are worth planning for when they have high impacts. We care about asteroid defense when that probability is much lower.
Humanity has a good chance of getting destroyed in this century if decision makers treat 0.001 the same way as 0.0000000001.
In what examples are are experts underconfident when they give 0.9 or 0.95 probabilities of an event happening.
I wasn’t trying to suggest it was; my apologies for (evidently) being insufficiently clear.
Yup, strongly agreed. But here the low-probability events we’re talking about here are things like “it turns out global warming wasn’t a big deal after all”. It would be sad to have spent a lot of money trying to reduce carbon dioxide emissions in that case, but it wouldn’t be much like (e.g.) being hit by an asteroid.
I don’t have examples to hand, I’m afraid (other than the IPCC example we’re discussing here, though actually all we know there is that their probability estimate is somewhere between 0.95 and 1, and is probably below 0.99 since they didn’t choose to say “virtually certain”. (Only “probably” because when they list what the terms mean they say 95-100% and not 95-99% for “extremely likely”, and the best explanation I can see for that is that they are reserving the right to say “extremely likely” rather than “virtually certain” sometimes even though they think the actual probability is over 99%. This is one reason why I suspect them of understating their certainty on purpose: they seem to have gone out of their way to provide themselves with a way to do that.)