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Ask HN: John Cook et al., 2013 a climate propaganda piece?

The study[0] popularized the "97% consensus" that 97% of climate scientists agree that humans are the main contributing factor to the observed global warming. As far as I can tell, that 97% number includes those scientists who think humans contribute more than zero. So a more honest conclusion would have been: 97% of climate scientists agree that humans have a non-zero impact on the global warming. But they warped this into: 97% agree we are the main contributing factor. This particular study is wildly misleading and borders on scientific misconduct? [0] https://iopscience.iop.org/article/10.1088/1748-9326/8/2/024024/pdf

yawpitch 4y ago
The study never states that 97% of climate scientists have a particular opinion on the matter. It doesn’t come remotely close to saying that. Wherever you and popular opinion are getting that “97% of climate scientists” idea, it isn’t from this paper. What it DOES say is that ~97% of papers whose abstract states a clear opinion on Anthropogenic Global Warming agree with the idea that Anthropogenic (literally “human-caused”) Global Warming is, in fact, human-caused. Shocking, I know, that the majority of climate scientists who state an opinion about human-caused global warming believe that such global warming is, in fact, human-caused. Just shocking. That 97% consensus amongst papers that state an opinion doesn’t represent the majority of climate scientists who published during the period of the meta-study… the paper clearly states that the majority of climate-related papers didn’t state an opinion at all. Shocking, again, I know, that less than half of climate related papers expressed an opinion on the subject at all… but there you have it. Basically they’ve told you up front what the number show… the vast majority of papers that care enough to state an opinion support the mainstream consensus. Which… again… is shocking, to someone looking for a nit to pick. What it isn’t is particularly misleading, or anything like an example of scientific misconduct. > The number of papers rejecting AGW is a miniscule proportion of the published research, with the percentage slightly decreasing over time. Or, in other words, few papers whose authors have the requisite expertise to successfully navigate peer review disagree with those who have the expertise required to review their work. > Among papers expressing a position on AGW, an overwhelming percentage (97.2% based on self-ratings, 97.1% based on abstract ratings) endorses the scientific consensus on AGW. Or, in other words, the experts who state an opinion overwhelmingly share their opinion, and both methods of confirming their consensus tally to roughly the same result. What you haven’t done here is poke holes in the science, or their conclusion… what you’ve done is poked holes in the inferences you’ve made from bad reporting on the science. Which is, again, shocking. Nevertheless, it’s much greater than non-zero… those who know enough to state an opinion state that opinion.
- late_to_party 4y ago
  I accept much of your feedback. It seems the media has done a lot of twisting here. Still remains to explain why adding level 1, level 2 and level 3 together and calling it consensus is not wildly misleading. They dont even define what a consensus is but it is implied that it means humans are the main contributing factor. Here are the endorsement levels: 1. Explicit endorsement with quantification. Explicitly states that humans are the primary cause of recent global warming 2. Explicit endorsement without quantification Explicitly states humans are causing global warming or refers to anthropogenic global warming/climate change as a known fact 3. Implicit endorsement Implies humans are causing global warming. E.g., research assumes greenhouse gas emissions cause warming without explicitly stating humans are the cause As a reminder, they lumped all these together to produce the 97% number. This is a 97% consensus that humans have a non-zero impact. It is NOT a 97% consensus that humans are the main contributing factor. EDIT: The paper does not list the data for these endorsement levels so we cannot know the distribution.
  - yawpitch 4y ago
    > The paper does not list the data for these endorsement levels so we cannot know the distribution. There’s a link to supplementary data at the top of the paper, and a further link within the paper explicitly stating to look there for more details: I haven’t checked, but it’s entirely possible that a breakdown of the 1-3 agreement levels is available there, just not explicitly described, which is perfectly fine if an explicitly listing of such data doesn’t do anything to elucidate the answer to the research question. And, except for someone seeking to find or manufacture dissent, there’s nothing wrong with this “lumping together”… doing so DOES NOT imply “97% consensus that [human impact != 0]”, it DOES imply “97% consensus that [human impact > 0]”. Now, that may look like splitting hairs, but what you are providing here is the idea that “approximately or nearly zero” is a likely position for those who didn’t explicitly quantify, and that’s simply not the case… anyone with such weak agreement is, if anything, MORE inclined to quantify their position on the power effect, not less. To Godwin early, you’re acting as if there’s a problem with lumping together these groups that sum to a consensus: 1) The Nazis were responsible for killing [a series of specific, very large number of] Jews, Poles, Russians, Masons, LGBTQT+, etc individuals in the Holocaust. 2) The Nazis were responsible for killing untold millions in the Holocaust. 3) The Nazis were responsible for the Holocaust. … and calling that “97% consensus that the Nazis were responsible for a non-zero number of deaths in the Holocaust”. The reality, presented by this and numerous other papers, is that an overwhelming majority of those with sufficient expertise to form an opinion share the opinion that anthropogenic climate change is — shockingly — anthropogenic… to an overwhelming degree they agree that such impact is substantial enough to mean not merely contributory (Imp != 0 and Imp > 0 where Imp is potentially small) but to rise to responsibility ((Imp != 0 and Imp > 0 where Imp is not small)… those who oppose this consensus are, usually, not experts or, if experts, not publishing their opinions in their abstracts. Now, there is a legit research question there… of the substantial number of papers that stated no opinion whatsoever (not part of the 97% of the opinionated you’re not really succeeding to nitpick), how many held a conflicting-to-consensus opinion but didn’t state it, and what factors led to them not stating that opinion? The authors who didn’t place a stake are where you should be focusing, rather than letting your confirmation bias try and put a wedge where it won’t fit.

yawpitch 4y ago

The study never states that 97% of climate scientists have a particular opinion on the matter. It doesn’t come remotely close to saying that. Wherever you and popular opinion are getting that “97% of climate scientists” idea, it isn’t from this paper. What it DOES say is that ~97% of papers whose abstract states a clear opinion on Anthropogenic Global Warming agree with the idea that Anthropogenic (literally “human-caused”) Global Warming is, in fact, human-caused. Shocking, I know, that the majority of climate scientists who state an opinion about human-caused global warming believe that such global warming is, in fact, human-caused. Just shocking. That 97% consensus amongst papers that state an opinion doesn’t represent the majority of climate scientists who published during the period of the meta-study… the paper clearly states that the majority of climate-related papers didn’t state an opinion at all. Shocking, again, I know, that less than half of climate related papers expressed an opinion on the subject at all… but there you have it. Basically they’ve told you up front what the number show… the vast majority of papers that care enough to state an opinion support the mainstream consensus. Which… again… is shocking, to someone looking for a nit to pick. What it isn’t is particularly misleading, or anything like an example of scientific misconduct. > The number of papers rejecting AGW is a miniscule proportion of the published research, with the percentage slightly decreasing over time. Or, in other words, few papers whose authors have the requisite expertise to successfully navigate peer review disagree with those who have the expertise required to review their work. > Among papers expressing a position on AGW, an overwhelming percentage (97.2% based on self-ratings, 97.1% based on abstract ratings) endorses the scientific consensus on AGW. Or, in other words, the experts who state an opinion overwhelmingly share their opinion, and both methods of confirming their consensus tally to roughly the same result. What you haven’t done here is poke holes in the science, or their conclusion… what you’ve done is poked holes in the inferences you’ve made from bad reporting on the science. Which is, again, shocking. Nevertheless, it’s much greater than non-zero… those who know enough to state an opinion state that opinion.

late_to_party 4y ago
I accept much of your feedback. It seems the media has done a lot of twisting here. Still remains to explain why adding level 1, level 2 and level 3 together and calling it consensus is not wildly misleading. They dont even define what a consensus is but it is implied that it means humans are the main contributing factor. Here are the endorsement levels: 1. Explicit endorsement with quantification. Explicitly states that humans are the primary cause of recent global warming 2. Explicit endorsement without quantification Explicitly states humans are causing global warming or refers to anthropogenic global warming/climate change as a known fact 3. Implicit endorsement Implies humans are causing global warming. E.g., research assumes greenhouse gas emissions cause warming without explicitly stating humans are the cause As a reminder, they lumped all these together to produce the 97% number. This is a 97% consensus that humans have a non-zero impact. It is NOT a 97% consensus that humans are the main contributing factor. EDIT: The paper does not list the data for these endorsement levels so we cannot know the distribution.
- yawpitch 4y ago
  > The paper does not list the data for these endorsement levels so we cannot know the distribution. There’s a link to supplementary data at the top of the paper, and a further link within the paper explicitly stating to look there for more details: I haven’t checked, but it’s entirely possible that a breakdown of the 1-3 agreement levels is available there, just not explicitly described, which is perfectly fine if an explicitly listing of such data doesn’t do anything to elucidate the answer to the research question. And, except for someone seeking to find or manufacture dissent, there’s nothing wrong with this “lumping together”… doing so DOES NOT imply “97% consensus that [human impact != 0]”, it DOES imply “97% consensus that [human impact > 0]”. Now, that may look like splitting hairs, but what you are providing here is the idea that “approximately or nearly zero” is a likely position for those who didn’t explicitly quantify, and that’s simply not the case… anyone with such weak agreement is, if anything, MORE inclined to quantify their position on the power effect, not less. To Godwin early, you’re acting as if there’s a problem with lumping together these groups that sum to a consensus: 1) The Nazis were responsible for killing [a series of specific, very large number of] Jews, Poles, Russians, Masons, LGBTQT+, etc individuals in the Holocaust. 2) The Nazis were responsible for killing untold millions in the Holocaust. 3) The Nazis were responsible for the Holocaust. … and calling that “97% consensus that the Nazis were responsible for a non-zero number of deaths in the Holocaust”. The reality, presented by this and numerous other papers, is that an overwhelming majority of those with sufficient expertise to form an opinion share the opinion that anthropogenic climate change is — shockingly — anthropogenic… to an overwhelming degree they agree that such impact is substantial enough to mean not merely contributory (Imp != 0 and Imp > 0 where Imp is potentially small) but to rise to responsibility ((Imp != 0 and Imp > 0 where Imp is not small)… those who oppose this consensus are, usually, not experts or, if experts, not publishing their opinions in their abstracts. Now, there is a legit research question there… of the substantial number of papers that stated no opinion whatsoever (not part of the 97% of the opinionated you’re not really succeeding to nitpick), how many held a conflicting-to-consensus opinion but didn’t state it, and what factors led to them not stating that opinion? The authors who didn’t place a stake are where you should be focusing, rather than letting your confirmation bias try and put a wedge where it won’t fit.