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No. They aren't "only looking at feedback mechanisms that reinforce cataclysm." Modelers include every feedback that they can quantify well enough to include an

No. They aren't "only looking at feedback mechanisms that reinforce cataclysm." Modelers include every feedback that they can quantify well enough to include and the ones they don't understand well enough are studied carefully to be able to work out what the uncertainties are. Scientists 50 years ago predicted that we would be at around 1C (1.8F) of warming by 2020 with a 40% over preindustrial co2 level. That's exactly what we have now. They predicted almost perfectly today's climate decades before it came to pass. That may not seem like a big deal until you understand that global temperatures haven't been this high in 130,000 years. It isn't being recognized properly yet in the media, but the stunning accuracy of predictions by climate modelers is one of the greatest achievements in the history Earth sciences.

mistermann 7y ago
This sounds like you're saying that 50 years ago there was a single climate model, upon which significant consensus among scientists had been reached, that predicted a 1C temperature rise. I've read quite a few articles and discussions on this topic but have never heard this before. Am I misunderstanding you? If not, do you have a link that discusses this?
- phaemon 7y ago
  Perhaps the Sawyer paper from 1973? https://www.carbonbrief.org/analysis-how-well-have-climate-models-projected-global-warming https://www.carbonbrief.org/analysis-how-well-have-climate-m...
  - mistermann 7y ago
    Surely there was one model that happened to come up with the right prediction, I would assume there were multiple. But my questions is whether there was one model with consensus support (which seems to be the claim), which would be necessary to rule out survivorship bias.
    - phaemon 7y ago
      > Surely there was one model that happened to come up with the right prediction What does that mean? This "model" is someone sitting down and, using what we know of physics, calculating how something will warm up when you add some extra energy (in this case, the earth). You surely don't think that physics works by people randomly guessing answers and then one of them "happened" to be correct? You don't, do you?!
      - rbavocadotree 7y ago
        From the 1975 US National Academy of Sciences/National Research Council Report ...we do not have a good quantitative understanding of our climate machine and what determines its course. Without the fundamental understanding, it does not seem possible to predict climate... [0] The point is that there were a lot of climate models done in the 70's, and only a few of them were accurate. No one was randomly guessing, but the model you gave was not the consensus. [0] https://skepticalscience.com/ice-age-predictions-in-1970s-intermediate.htm https://skepticalscience.com/ice-age-predictions-in-1970s-in...
      - jazzyjackson 7y ago
        When a thousand hedge funds hire mathematicians and economists to create models of the global economy so that they can predict whether individual stocks will move up or down over different timescales, their task is similar to predicting the weather. Some will beat the market, many won't. Are they guessing? Maybe that's a bad analogy, but my point is that climate is a chaotic system, and detailed models might be right and might be wrong. It's not that the scientists are guessing, of course the science is methodical - but the performance of the model might not be better than guessing, hence the speculation of survivorship bias. There were lots of climate models over the last century, was there consensus around a paper that is now proven correct? Or were there a hundred models that were off and one that, yes, happened to be correct. I don't know the answer.
        monknomo 7y ago
        I think an individual stock in this analogy would be "Will it rain in Duluth". Climate predictions, to use your economic model, would be more along the lines of "Will stocks continue to rise on the whole over the next 100 years?"
- atotic 7y ago
  "Evaluating the performance of past climate model projections" https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2019GL085378 https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2019... "We found that climate models – even those published back in the 1970s – did remarkably well, with 14 out of the 17 projections statistically indistinguishable from what actually occurred."
  - mistermann 7y ago
    Yes, I read that report and participated in the subsequent discussion [0] where I raised a number of concerns with the study, but wasn't able to find anyone who would seriously and objectively address them. Frustrated by the unwillingness of anyone to engage in rigorous discussion in that thread, I also contacted the authors to see if they were willing to address some of the concerns. Unfortunately, I did not hear back. I must confess, this strange combination of group declaration that "the science is in", combined with complete refusal to discuss "the science", leaves me feeling a bit suspicious about the degree to which anyone has actually read the science, or is thinking critically on this matter. If you could address some of the concerns I raised in [0], I would be delighted. [0] https://news.ycombinator.com/item?id=21708936 https://news.ycombinator.com/item?id=21708936
    - mturmon 7y ago
      > I raised a number of concerns with the study, but wasn't able to find anyone who would seriously and objectively address them. This is an inaccurate summary of that thread, in which you raised a simple accusation that the article cherry-picked the models, were swatted down with a citation from the article referenced in the OP, and then retreated into a maze of long, twisty replies that failed to raise any other specific points. Your comments in this thread have had the same flavor. Consider brevity and specificity.
      - mistermann 7y ago
        > This is an inaccurate summary of that thread, in which you raised a simple accusation that the article cherry-picked the models Ironically, or not, your summary of my summary of that thread is inaccurate. > "you raised a simple accusation that the article cherry-picked the models" is not what I did. What I did do is ask for an explanation of how we know no cherry picking occurred. Their methodology for article selection was not published, so therefore it cannot be reproduced. I emailed the authors asking for clarification, and they did not reply. > were swatted down with a citation from the article referenced in the OP "swatted down", but didn't address my actual question, rather re-reffering to the original ambiguous wording that I was complaining about. A reproducible methodology could clear up the uncertainty (and please note, my claim is that there is uncertainty not that there is wrongdoing), yet no methodology was offered in the original paper, and the authors did not reply to the request. In such situations, I adopt a position of "Unknown - more information is required", but obviously others have a much more flexible approach to what they're willing to believe. Although, I wonder if this approach varies depending on the subject - would be interesting to read up on. > and then retreated into a maze of long, twisty replies that failed to raise any other specific points "Mazes of long, twisty replies", and failures to "raise any other specific points" are a common consequences when one party in a discussion is unwilling to directly address questions as asked, and the other party's response to that is re-asking the same question. > Your comments in this thread have had the same flavor. Indeed they do, as do the replies: unwillingness to directly address questions as asked. > Consider brevity and specificity. I will do so. In return, please consider honesty, epistemic humility, your willingness to acknowledge that ambiguity often exists in written language, and whether a lack of 100% agreement should be interpreted as opposition, as opposed to curiosity and strictness. Sometimes those who appear to be your enemy may actually be some of your best friends. EDIT: Here's another way to look at it (a better description of my main intent): "conspiracy theorists" and "deniers" are a problem, to some degree, in broad acceptance of climate change messaging, agreed? Might it be a good idea to consider whether there are some flaws in the messaging that could be improved, that would result in reducing the material they have to work with in any influence campaigns?

mistermann 7y ago

This sounds like you're saying that 50 years ago there was a single climate model, upon which significant consensus among scientists had been reached, that predicted a 1C temperature rise. I've read quite a few articles and discussions on this topic but have never heard this before. Am I misunderstanding you? If not, do you have a link that discusses this?

phaemon 7y ago
Perhaps the Sawyer paper from 1973? https://www.carbonbrief.org/analysis-how-well-have-climate-models-projected-global-warming https://www.carbonbrief.org/analysis-how-well-have-climate-m...
- mistermann 7y ago
  Surely there was one model that happened to come up with the right prediction, I would assume there were multiple. But my questions is whether there was one model with consensus support (which seems to be the claim), which would be necessary to rule out survivorship bias.
  - phaemon 7y ago
    > Surely there was one model that happened to come up with the right prediction What does that mean? This "model" is someone sitting down and, using what we know of physics, calculating how something will warm up when you add some extra energy (in this case, the earth). You surely don't think that physics works by people randomly guessing answers and then one of them "happened" to be correct? You don't, do you?!
    - rbavocadotree 7y ago
      From the 1975 US National Academy of Sciences/National Research Council Report ...we do not have a good quantitative understanding of our climate machine and what determines its course. Without the fundamental understanding, it does not seem possible to predict climate... [0] The point is that there were a lot of climate models done in the 70's, and only a few of them were accurate. No one was randomly guessing, but the model you gave was not the consensus. [0] https://skepticalscience.com/ice-age-predictions-in-1970s-intermediate.htm https://skepticalscience.com/ice-age-predictions-in-1970s-in...
    - jazzyjackson 7y ago
      When a thousand hedge funds hire mathematicians and economists to create models of the global economy so that they can predict whether individual stocks will move up or down over different timescales, their task is similar to predicting the weather. Some will beat the market, many won't. Are they guessing? Maybe that's a bad analogy, but my point is that climate is a chaotic system, and detailed models might be right and might be wrong. It's not that the scientists are guessing, of course the science is methodical - but the performance of the model might not be better than guessing, hence the speculation of survivorship bias. There were lots of climate models over the last century, was there consensus around a paper that is now proven correct? Or were there a hundred models that were off and one that, yes, happened to be correct. I don't know the answer.
      - monknomo 7y ago
        I think an individual stock in this analogy would be "Will it rain in Duluth". Climate predictions, to use your economic model, would be more along the lines of "Will stocks continue to rise on the whole over the next 100 years?"
atotic 7y ago
"Evaluating the performance of past climate model projections" https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2019GL085378 https://agupubs.onlinelibrary.wiley.com/doi/abs/10.1029/2019... "We found that climate models – even those published back in the 1970s – did remarkably well, with 14 out of the 17 projections statistically indistinguishable from what actually occurred."
- mistermann 7y ago
  Yes, I read that report and participated in the subsequent discussion [0] where I raised a number of concerns with the study, but wasn't able to find anyone who would seriously and objectively address them. Frustrated by the unwillingness of anyone to engage in rigorous discussion in that thread, I also contacted the authors to see if they were willing to address some of the concerns. Unfortunately, I did not hear back. I must confess, this strange combination of group declaration that "the science is in", combined with complete refusal to discuss "the science", leaves me feeling a bit suspicious about the degree to which anyone has actually read the science, or is thinking critically on this matter. If you could address some of the concerns I raised in [0], I would be delighted. [0] https://news.ycombinator.com/item?id=21708936 https://news.ycombinator.com/item?id=21708936
  - mturmon 7y ago
    > I raised a number of concerns with the study, but wasn't able to find anyone who would seriously and objectively address them. This is an inaccurate summary of that thread, in which you raised a simple accusation that the article cherry-picked the models, were swatted down with a citation from the article referenced in the OP, and then retreated into a maze of long, twisty replies that failed to raise any other specific points. Your comments in this thread have had the same flavor. Consider brevity and specificity.
    - mistermann 7y ago
      > This is an inaccurate summary of that thread, in which you raised a simple accusation that the article cherry-picked the models Ironically, or not, your summary of my summary of that thread is inaccurate. > "you raised a simple accusation that the article cherry-picked the models" is not what I did. What I did do is ask for an explanation of how we know no cherry picking occurred. Their methodology for article selection was not published, so therefore it cannot be reproduced. I emailed the authors asking for clarification, and they did not reply. > were swatted down with a citation from the article referenced in the OP "swatted down", but didn't address my actual question, rather re-reffering to the original ambiguous wording that I was complaining about. A reproducible methodology could clear up the uncertainty (and please note, my claim is that there is uncertainty not that there is wrongdoing), yet no methodology was offered in the original paper, and the authors did not reply to the request. In such situations, I adopt a position of "Unknown - more information is required", but obviously others have a much more flexible approach to what they're willing to believe. Although, I wonder if this approach varies depending on the subject - would be interesting to read up on. > and then retreated into a maze of long, twisty replies that failed to raise any other specific points "Mazes of long, twisty replies", and failures to "raise any other specific points" are a common consequences when one party in a discussion is unwilling to directly address questions as asked, and the other party's response to that is re-asking the same question. > Your comments in this thread have had the same flavor. Indeed they do, as do the replies: unwillingness to directly address questions as asked. > Consider brevity and specificity. I will do so. In return, please consider honesty, epistemic humility, your willingness to acknowledge that ambiguity often exists in written language, and whether a lack of 100% agreement should be interpreted as opposition, as opposed to curiosity and strictness. Sometimes those who appear to be your enemy may actually be some of your best friends. EDIT: Here's another way to look at it (a better description of my main intent): "conspiracy theorists" and "deniers" are a problem, to some degree, in broad acceptance of climate change messaging, agreed? Might it be a good idea to consider whether there are some flaws in the messaging that could be improved, that would result in reducing the material they have to work with in any influence campaigns?