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I don’t disagree that there could be lots of other forcings/tipping points etc, but I hear lots of conjecture and don’t see the effect as much in actual predict

I don’t disagree that there could be lots of other forcings/tipping points etc, but I hear lots of conjecture and don’t see the effect as much in actual predictions / models. I do disagree that if they are not included in our models, then we must be systemically underestimating warming. Why do you assume the missing effects will make the situation worse? If the model is missing positive forcings, what makes you so sure that they have included all the negative forcings?

paulmd 3y ago
> Why do you assume the missing effects will make the situation worse? > If the model is missing positive forcings, what makes you so sure that they have included all the negative forcings? I don't think they have included all the negative forcings, but I think that's irrelevant because the observed evidence is that the unincluded positive forcings are significantly larger than the unincluded negative forcings. All that matters is the net balance, and the fact that the climate is systematically exceeding the most wildly pessimistic predictions our model provides, shows that the model is not neutrally-calibrated with the present assumptions. There is a significant positive net balance (including any negative forcing) that our model is understating. At any given time that could be a lot or a little, but, right now it seems to be "a lot". And the fact that it's been that way for 30 years, says that this isn't a short-term thing. And in fact the rate of departure from the model is accelerating too - the second derivative and third derivates seem to be strongly positive. We are not just getting farther away from the model, we are getting farther away faster and accelerating as we do it. Could that all change tomorrow when some other effect kicks in and plunges us into a nuclear winter or whatever? No, probably not, but that's the kind of hope that conservative media has been selling people for 40 years. When scientists give a neutral "well, anything could happen but..." response, all the public hears is "you're saying there's a chance". Nope, we're blasting through all the guardrails of the model on a yearly basis, we're pretty fucked. And yes, there's also the possibility that we've unintentionally been geoengineering something for a while and when we stop ships from putting out sulfur (because it causes acid rain) that we suddenly jump even higher. Getting to the "disease, famine, endless wildfires (way too many to keep under control), storms with the power to level cities and blot out the sun" portion of the Toby Ruins It For Everyone video. https://www.youtube.com/watch?v=Uc1vrO6iL0U https://www.youtube.com/watch?v=Uc1vrO6iL0U And yes, it is absolutely too late to stop and the best we can do is try to limit the impacts... which will continue to worsen until we do (and then for about another 20 years after we cease net emissions). Which is why the conservative media will jump right from "it's not real/it's not human caused/it's not bad enough to do anything about it" right to "wow it's too late, let's do nothing". Which is the same thing they've wanted us to do all along, ofc...
- brutusborn 3y ago
  What’s the evidence for “observed evidence is that the unincluded positive forcings are significantly larger than the unincluded negative forcings”?
  - paulmd 3y ago
    The fact that we're continually exceeding the most pessimistic projections the models can produce on a yearly basis, even after repeatedly recalibrating it to build in even more pessimistic assumptions, and that we're tending to depart more strongly from even the pessimistic models. This implies that the models are broadly understating these feedback loops, that they are net-balance in the positive-feedback direction, and that they are becoming more active in the current climate behavior regime.
    - RandomLensman 3y ago
      Strictly speaking that is not sufficient as it only holds for the current part of the climate evolution and not the future one. It could be that currently positive forcing is underestimated while in the future negative forcing is.
    - brutusborn 3y ago
      That isn’t evidence of the previous statement. If we continually exceed model predictions, it could be from underestimating known positive forcings, overestimating known negative forcings, or some combination of unknown positive/negative forcings. Essentially I think continuous failed predictions are a red flag for any model, especially one as critical to us as the global climate models.
- RandomLensman 3y ago
  If it is too late to stop might as well aggressively geoengineer and see if it pans out, no? We sort of know we can cool the planet if we wanted to.
  - adrianN 3y ago

paulmd 3y ago

> Why do you assume the missing effects will make the situation worse? > If the model is missing positive forcings, what makes you so sure that they have included all the negative forcings? I don't think they have included all the negative forcings, but I think that's irrelevant because the observed evidence is that the unincluded positive forcings are significantly larger than the unincluded negative forcings. All that matters is the net balance, and the fact that the climate is systematically exceeding the most wildly pessimistic predictions our model provides, shows that the model is not neutrally-calibrated with the present assumptions. There is a significant positive net balance (including any negative forcing) that our model is understating. At any given time that could be a lot or a little, but, right now it seems to be "a lot". And the fact that it's been that way for 30 years, says that this isn't a short-term thing. And in fact the rate of departure from the model is accelerating too - the second derivative and third derivates seem to be strongly positive. We are not just getting farther away from the model, we are getting farther away faster and accelerating as we do it. Could that all change tomorrow when some other effect kicks in and plunges us into a nuclear winter or whatever? No, probably not, but that's the kind of hope that conservative media has been selling people for 40 years. When scientists give a neutral "well, anything could happen but..." response, all the public hears is "you're saying there's a chance". Nope, we're blasting through all the guardrails of the model on a yearly basis, we're pretty fucked. And yes, there's also the possibility that we've unintentionally been geoengineering something for a while and when we stop ships from putting out sulfur (because it causes acid rain) that we suddenly jump even higher. Getting to the "disease, famine, endless wildfires (way too many to keep under control), storms with the power to level cities and blot out the sun" portion of the Toby Ruins It For Everyone video. https://www.youtube.com/watch?v=Uc1vrO6iL0U https://www.youtube.com/watch?v=Uc1vrO6iL0U And yes, it is absolutely too late to stop and the best we can do is try to limit the impacts... which will continue to worsen until we do (and then for about another 20 years after we cease net emissions). Which is why the conservative media will jump right from "it's not real/it's not human caused/it's not bad enough to do anything about it" right to "wow it's too late, let's do nothing". Which is the same thing they've wanted us to do all along, ofc...

brutusborn 3y ago
What’s the evidence for “observed evidence is that the unincluded positive forcings are significantly larger than the unincluded negative forcings”?
- paulmd 3y ago
  The fact that we're continually exceeding the most pessimistic projections the models can produce on a yearly basis, even after repeatedly recalibrating it to build in even more pessimistic assumptions, and that we're tending to depart more strongly from even the pessimistic models. This implies that the models are broadly understating these feedback loops, that they are net-balance in the positive-feedback direction, and that they are becoming more active in the current climate behavior regime.
  - RandomLensman 3y ago
    Strictly speaking that is not sufficient as it only holds for the current part of the climate evolution and not the future one. It could be that currently positive forcing is underestimated while in the future negative forcing is.
  - brutusborn 3y ago
    That isn’t evidence of the previous statement. If we continually exceed model predictions, it could be from underestimating known positive forcings, overestimating known negative forcings, or some combination of unknown positive/negative forcings. Essentially I think continuous failed predictions are a red flag for any model, especially one as critical to us as the global climate models.
RandomLensman 3y ago
If it is too late to stop might as well aggressively geoengineer and see if it pans out, no? We sort of know we can cool the planet if we wanted to.
- adrianN 3y ago