Official Global Warming thread (merged)

So, it's your claim that the Nobel winning IPCC assessment report is more so a scientific document and Darriulat's problem was only with the summary that was produced by 65 hand picked climate scientists from around the world? You know, the summary that was meant to be a scientific analaysis of the most authoritative research? You know the Nobel winning summary? And, that you know who produced these papers the summary was based upon and you want to know if I know? Those are your arguments? I don't think you have a clue what you are talking about. You really don't have a clue.

What are you talking about? The assessment reports (I believe we are at 5 now unless I missed one or added one) itself is authored by teams for each chapter. The teams are led by experts in the field pertinent to that chapter. These teams are largely made up of the scientific community, though that depends on the chapter - some stray into the social sciences.

The summary for policy makers is a much-condensed and simplified chapter that is intended to capture the overall tone of the report in something more digestible by policy makers. While based on the assessment report (which is based on the scientific literature), it is necessarily less scientific because an attempt is made to package it for policy makers. This includes some of the confidence intervals such as we will see warming greater than 3C with 95% confidence.

I believe this was a key change from the 3rd to the 4th assessment. Before, words like "very likely" or "likely" were used rather than percentages. My take from looking over your comments from Darriulat were that an issue being taken was with regard to placing specific numbers of confidence on statements where there was no scientific way of arriving at the number. I was agreeing that I think they wanted to diverge from loose terms like "very likely" and move to terms like "with 95% confidence" and that I am not sure there was a real scientific basis for getting that specific.

However, my larger point was that I don't see how assessment reports written based on the scientific literature are somehow a dagger in the heart of the climate change argument and at the scientists have changed their tune .... The report is written from their tune.
 
What are you talking about? The assessment reports (I believe we are at 5 now unless I missed one or added one) itself is authored by teams for each chapter. The teams are led by experts in the field pertinent to that chapter. These teams are largely made up of the scientific community, though that depends on the chapter - some stray into the social sciences.

The summary for policy makers is a much-condensed and simplified chapter that is intended to capture the overall tone of the report in something more digestible by policy makers. While based on the assessment report (which is based on the scientific literature), it is necessarily less scientific because an attempt is made to package it for policy makers. This includes some of the confidence intervals such as we will see warming greater than 3C with 95% confidence.

I believe this was a key change from the 3rd to the 4th assessment. Before, words like "very likely" or "likely" were used rather than percentages. My take from looking over your comments from Darriulat were that an issue being taken was with regard to placing specific numbers of confidence on statements where there was no scientific way of arriving at the number. I was agreeing that I think they wanted to diverge from loose terms like "very likely" and move to terms like "with 95% confidence" and that I am not sure there was a real scientific basis for getting that specific.

However, my larger point was that I don't see how assessment reports written based on the scientific literature are somehow a dagger in the heart of the climate change argument and at the scientists have changed their tune .... The report is written from their tune.

You'd expect that most politicians had taken high school science wouldn't you? The summary didn't even pass the standard for a high school science book. It is a dagger in the heart because 65 hand picked biased scientists could not produce a report of all the best and most authoritative literature and research on climate change with any degree of confidence. Darriulat said go back and study 10 more years and maybe you'll come up with something that has a modicum of confidence. (By the way I suggest they don't use Greenpeace literature in their bibliographies.)

P.S.-I should have said it wouldn't pass the standard for a science book in the country I grew up in. However, what you liberals have done to our schools I don't know now.
 
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You'd expect that most politicians had taken high school science wouldn't you? The summary didn't even pass the standard for a high school science book. It is a dagger in the heart because 65 hand picked biased scientists could not produce a report of all the best and most authoritative literature and research on climate change with any degree of confidence. Darriulat said go back and study 10 more years and maybe you'll come up with something that has a modicum of confidence. (By the way I suggest they don't use Greenpeace literature in their bibliographies.)

Darriulat is arguing they can't use the confidence intervals in the way they are using them. I would agree it is likely improper to do so . That does not discredit the full assessment report as a scientific assessment of the body of literature nor does it discredit the summary as a summary for policy makers. I would personally rather the authors leave off the exact confidence intervals because they really aren't that. The problem was that policy makers were, for understandable reasons, not sure what terms like 'very likely', 'likely', 'more likely than not', etc. really meant. So the scientists made attempts at quantifying what those terms meant. That doesn't smell right in a pure scientific sense - and for scientists who haven't been put in the position of communicating complex scientific findings to individuals who are generally scientifically illiterate, there is a general unwillingness to bend 'the rules' and mix terminology (that is to use subjective confidence intervals - that is, exact numbers - to describe scientific results).

None of this represents a dagger in the heart of climate science or the assessment report. The individuals charged with putting together the summary for policy makers are pulled from the lead authors of the individual chapters - and those authors are pulled from multiple experts in their respective fields. It is not a climate scientist attacking the climate science in the assessment or climate change theory. I know a lead author of the climate modeling chapter and have passing knowledge of others. They are well-respected, well-credentialed leaders in that field. They are not amateurs and they have nor 'abandoned' climate change studies.

It is unfactual to say that only amateurs cling to climate change theories and that the scientists have moved on. The arguments you are citing are attacking the presentation of the summary. That the researchers are stepping beyond where they should in an attempt to make things more digestible.

The heart of the argument is that it is not rigorous to place precise scientific-looking confidence intervals on something that is not directly calculated as such. To place such precision on an estimate can imply more certainty than the models really afford and that can lead to misunderstandings. Furthermore, if the model says that there is 95% confidence we'll see >3C warming, does that mean we have 95% confidence that we'll see that? Do we have 100% confidence in the model? I doubt it. Are we certain the model is at least conservatively low? Probably not. Based on that, I get the argument that is being presented about the SPM.

HOWEVER, I completely disagree with how you're construing it.
 
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Darriulat is arguing they can't use the confidence intervals in the way they are using them. I would agree it is likely improper to do so . That does not discredit the full assessment report as a scientific assessment of the body of literature nor does it discredit the summary as a summary for policy makers. I would personally rather the authors leave off the exact confidence intervals because they really aren't that. The problem was that policy makers were, for understandable reasons, not sure what terms like 'very likely', 'likely', 'more likely than not', etc. really meant. So the scientists made attempts at quantifying what those terms meant. That doesn't smell right in a pure scientific sense - and for scientists who haven't been put in the position of communicating complex scientific findings to individuals who are generally scientifically illiterate, there is a general unwillingness to bend 'the rules' and mix terminology (that is to use subjective confidence intervals - that is, exact numbers - to describe scientific results).

None of this represents a dagger in the heart of climate science or the assessment report. The individuals charged with putting together the summary for policy makers are pulled from the lead authors of the individual chapters - and those authors are pulled from multiple experts in their respective fields. It is not a climate scientist attacking the climate science in the assessment or climate change theory. I know a lead author of the climate modeling chapter and have passing knowledge of others. They are well-respected, well-credentialed leaders in that field. They are not amateurs and they have nor 'abandoned' climate change studies.

It is unfactual to say that only amateurs cling to climate change theories and that the scientists have moved on. The arguments you are citing are attacking the presentation of the summary. That the researchers are stepping beyond where they should in an attempt to make things more digestible.

The heart of the argument is that it is not rigorous to place precise scientific-looking confidence intervals on something that is not directly calculated as such. To place such precision on an estimate can imply more certainty than the models really afford and that can lead to misunderstandings. Furthermore, if the model says that there is 95% confidence we'll see >3C warming, does that mean we have 95% confidence that we'll see that? Do we have 100% confidence in the model? I doubt it. Are we certain the model is at least conservatively low? Probably not. Based on that, I get the argument that is being presented about the SPM.

HOWEVER, I completely disagree with how you're construing it.

it sounds like what you're saying is that this so-called "settled science" is anything but settled, at least when it comes to the question of anthropogenic global warming/climate change
 
"The heart of the argument is that it is not rigorous to place precise scientific-looking confidence intervals on something that is not directly calculated as such. To place such precision on an estimate can imply more certainty than the models really afford and that can lead to misunderstandings. Furthermore, if the model says that there is 95% confidence we'll see >3C warming, does that mean we have 95% confidence that we'll see that? Do we have 100% confidence in the model? I doubt it. Are we certain the model is at least conservatively low? Probably not. Based on that, I get the argument that is being presented about the SPM.

HOWEVER, I completely disagree with how you're construing it."

No, that isn't what Darriulat is saying at all. He is saying you can't apply any level of confidence to the model at all-you can't say it is going to warm 1C, 3C, 5C, or anything anymore than you can say it is going to cool 1C, 3C or 5C. He is saying it is just a hypothetical at this point. He is saying there are so many unanswered questions and that the research to this date is inconclusive, you can't construct a model with any level of confidence, and that we are where we were 10 years ago or 20 years ago or however many years ago. Nothing. Do you get that? That is a dagger in the heart.
 
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I mean you have Judith Curry who is a serious climate scientist quoting von Hayek's 1974noble prize lecture:

"We know: of course, with regard to the market and similar social structures, a great many facts which we cannot measure and on which indeed we have only some very imprecise and general information. And because the effects of these facts in any particular instance cannot be confirmed by quantitative evidence, they are simply disregarded by those sworn to admit only what they regard as scientific evidence: they thereupon happily proceed on the fiction that the factors which they can measure are the only ones that are relevant."

Read her December 25th article. Global Warming Science is in deep do do.
 
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it sounds like what you're saying is that this so-called "settled science" is anything but settled, at least when it comes to the question of anthropogenic global warming/climate change

I wouldn't say that. The fundamental issue of attribution stands. Amount and effects have been and continue to be a matter of study.
 
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So I pose this one more time. Algore, in his quest to try and present "scientific" slides as if he knew what he was talking about, showed a slide in his inconvenient truth comedy that explained global warming and cooling cycles. Essentially, he showed a graph of scientific data charting temperature spikes every 200k years +/- about 10k - 15k years. There were 3 of these spikes if I remember correctly. We are currently about 250k years removed from the last temp spike. His data showed a rise in temps. Point is, he was using this slide to support man-made warming, what his slide showed was we are due for a warming trend, and when it warms, it does so quickly. I believe if we have done anything, we have stabilized the temperature or at least slowed the warm up. TIFWIW.
 
Sandvol - he is hammering home the second part of my confidence interval argument. You have 1) confidence interval from model simulation output and 2) confidence in model. The first is objective and the second isn't. His confidence in the models may be near zero. I haven't read enough of his stuff to say that for sure.

What I would say is that challenges like these - even if his confidence is zero - are not daggers in the heart, but rather shots in the arm. The climate science community needs to be challenged in healthy, scientific ways. To categorize it as a dagger in the heart is really just politicizing what is the scientific process playing out. Well-founded challenges should be embraced and either scientifically refuted or embraced.

And I think that he has a good point. To avoid getting too technical, the SPM states complex arguments in simple terms with *little to no* nuance. Anyone who knows my posting here knows that I get stuck in the nuance and believe detail and intellectual honesty are very important. As a scientist in industry, it is something I struggle with in communicating the results produced by my team to management. I think that in order to write the SPM, the lead authors end up overreaching by stating subjective concensus (around the validity of the models) as scientific confidence intervals in order to avoid hedging or providing too much detail / nuance. It isn't an easy thing to write - merging the science with the policy angle.
 
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So I pose this one more time. Algore, in his quest to try and present "scientific" slides as if he knew what he was talking about, showed a slide in his inconvenient truth comedy that explained global warming and cooling cycles. Essentially, he showed a graph of scientific data charting temperature spikes every 200k years +/- about 10k - 15k years. There were 3 of these spikes if I remember correctly. We are currently about 250k years removed from the last temp spike. His data showed a rise in temps. Point is, he was using this slide to support man-made warming, what his slide showed was we are due for a warming trend, and when it warms, it does so quickly. I believe if we have done anything, we have stabilized the temperature or at least slowed the warm up. TIFWIW.
What physical principle would you argue such a stabilization is based on?
 
What physical principle would you argue such a stabilization is based on?

Hey, I am speculating like all the other "scientists". If your buddy Algore's slides were correct, we are overdue for a temp spike. Has not the first thing to do with humans. The only difference in 250k years ago and now is us. What physical principal would you blame it on? Either we are slowing the temp increase or we have nothing to do with it if you take Algore's data as fact.
 
Hey, I am speculating like all the other "scientists". If your buddy Algore's slides were correct, we are overdue for a temp spike. Has not the first thing to do with humans. The only difference in 250k years ago and now is us. What physical principal would you blame it on? Either we are slowing the temp increase or we have nothing to do with it if you take Algore's data as fact.

I think you are misinterpreting something here. I'm not sure which plot you are talking about.

I'm not saying parts of his talk weren't wrong over over-exaggerated, but I'm not sure what you're talking about.

Regardless, if you think there is no physical basis for warming arguments and that the scientists are just making it up then I think we're not going to get anywhere.
 
I think you are misinterpreting something here. I'm not sure which plot you are talking about.

I'm not saying parts of his talk weren't wrong over over-exaggerated, but I'm not sure what you're talking about.

Regardless, if you think there is no physical basis for warming arguments and that the scientists are just making it up then I think we're not going to get anywhere.

The problem arises when scientists make predictions of doom that turn out to be patently false.

in 2003 it was claimed that due to AGW, the Himalayas would be snow free within a decade, didn't happen.

Post Katrina, "scientists" claimed that, due to AGW, hurricanes would become increasingly larger and more destructive, hasn't happened

the new canard now is that when asked why climate prediction models didn't predict the past decade's lack of warming, "scientists" claim that all that excess heat is being stored deep in the oceans

listening to the doom and gloom prophecies followed by excuse making is tiring. It's like conspiracy theorists who gleefully point out that a lack of evidence to prove their conspiracy is actually proof that a conspiracy exists.
 
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The problem arises when scientists make predictions of doom that turn out to be patently false.

in 2003 it was claimed that due to AGW, the Himalayas would be snow free within a decade, didn't happen.

Post Katrina, "scientists" claimed that, due to AGW, hurricanes would become increasingly larger and more destructive, hasn't happened

the new canard now is that when asked why climate prediction models didn't predict the past decade's lack of warming, "scientists" claim that all that excess heat is being stored deep in the oceans

listening to the doom and gloom prophecies followed by excuse making is tiring. It's like conspiracy theorists who gleefully point out that a lack of evidence to prove their conspiracy is actually proof that a conspiracy exists.

It is certainly a risk one runs when making predictions.

I'm not sure I'd lump the issue if stronger cyclones with the Himalayan ice. I think that the jury is still out there. If sea temperatures continue to climb, it is very likely stronger cyclones (not necessarily more frequent) will follow.

Predictions are made to give meaningful value to otherwise obscure numbers, such as 2 degrees of global average temperature rise. The problem is that if you miss the estimate - even if you are within the error of your model or if you realize you've missed some important physics in the model - then you will almost certainly have egg on your face.

It is a very tough scientific issue because if the policy impact of the science. It drives me a little batty to see climate scientists attacked in general for their work on the models when they truly are for the most part not the wing nuts that the other side of the spectrum argues they are. They are in general good scientists - certainly smart folks working on a hard problem. Their quality as scientists - that is, truly following the scientific method - is probably a little harmed by the pressure cooker effect of working on something at the interface with policy. At some point the community felt compelled to engage the policy debate directly. It has been tough sledding since from the standpoint of attacks flying back and forth. It means some scientists won't admit uncertainty as readily as they otherwise would to scientists because they don't think the public will understand the nuance and much of the public is left very distrustful of almost everything those scientists do.
 
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What physical principle would you argue such a stabilization is based on?

Hey, I am speculating like all the other "scientists". If your buddy Algore's slides were correct, we are overdue for a temp spike. Has not the first thing to do with humans. The only difference in 250k years ago and now is us. What physical principal would you blame it on? Either we are slowing the temp increase or we have nothing to do with it if you take Algore's data as fact.

:popcorn::popcorn:
 
Sandvol - he is hammering home the second part of my confidence interval argument. You have 1) confidence interval from model simulation output and 2) confidence in model. The first is objective and the second isn't. His confidence in the models may be near zero. I haven't read enough of his stuff to say that for sure.

What I would say is that challenges like these - even if his confidence is zero - are not daggers in the heart, but rather shots in the arm. The climate science community needs to be challenged in healthy, scientific ways. To categorize it as a dagger in the heart is really just politicizing what is the scientific process playing out. Well-founded challenges should be embraced and either scientifically refuted or embraced.

And I think that he has a good point. To avoid getting too technical, the SPM states complex arguments in simple terms with *little to no* nuance. Anyone who knows my posting here knows that I get stuck in the nuance and believe detail and intellectual honesty are very important. As a scientist in industry, it is something I struggle with in communicating the results produced by my team to management. I think that in order to write the SPM, the lead authors end up overreaching by stating subjective concensus (around the validity of the models) as scientific confidence intervals in order to avoid hedging or providing too much detail / nuance. It isn't an easy thing to write - merging the science with the policy angle.

He is saying they improperly used statistical terms like 95% confidence level when there were no confidence intervals that supported those statements. He stated it essentially invalidated the whole report. It is also not a 10 year hiatus in warming but a 15 year hiatus. He said the model is nothing more than a hypothetical at this point.
 
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I've already replied.

Oh yeah, saw that.....sorry.

And, I never said the climate isn't warming, much to the contrary. I am a big believer in planetary fluctuations. I simply believe that man has had very little effect on the temperature and I am not totally certain that the effect is actually known. What I am saying is that your boy Algore's slide actually proved nothing other than we are over due for a temperature spike. I don't deny climate CHANGE, I deny that man has had an appreciable effect on it.
 
Oh yeah, saw that.....sorry.

And, I never said the climate isn't warming, much to the contrary. I am a big believer in planetary fluctuations. I simply believe that man has had very little effect on the temperature and I am not totally certain that the effect is actually known. What I am saying is that your boy Algore's slide actually proved nothing other than we are over due for a temperature spike. I don't deny climate CHANGE, I deny that man has had an appreciable effect on it.

Not in the last 15-17 years.
 
He is saying they improperly used statistical terms like 95% confidence level when there were no confidence intervals that supported those statements. He stated it essentially invalidated the whole report. It is also not a 10 year hiatus in warming but a 15 year hiatus. He said the model is nothing more than a hypothetical at this point.

The 15 year no warming bit is just silly. If I use narrow reference frames, I can say there has been warning over the last 16 years and over the last 14 years but not the last 15. The absurdity of that shoud point out the flaw of looking at it that way.

As for the confidence intervals - there are confidence intervals in some models. Monte Carlo analysis can be applied with probability ranges for input terms and the result is a range of responses (i.e., warming predictions). From this, one can ascribe terms such as >95% confidence in a predicted warming of at least x degrees.

The problem is that this obviously doesn't really mean greater than 95% confidence in the result. The error in the model is not quantified in a wholistic fashion. So to go from models to general statements in confidence in results can be subjective. In the SPM, this likely crosses a line into overstepping bounds of scientific rigor. However the actual assessment report tends to toe that line more carefully.

The SPM is not a scientific document. That is the point I took away. The assessment report is more so, but it is in itself just an assessment of the true scientific work.
 
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Oh yeah, saw that.....sorry.

And, I never said the climate isn't warming, much to the contrary. I am a big believer in planetary fluctuations. I simply believe that man has had very little effect on the temperature and I am not totally certain that the effect is actually known. What I am saying is that your boy Algore's slide actually proved nothing other than we are over due for a temperature spike. I don't deny climate CHANGE, I deny that man has had an appreciable effect on it.

And that denial is based on a gut feel?
 
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