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I don’t know why you’re being downvoted. We simply don’t know. Experts couldn’t even predict COVID waves correctly (UK) but we think we can predict the entire p

by zpeti 5y ago

I don’t know why you’re being downvoted. We simply don’t know. Experts couldn’t even predict COVID waves correctly (UK) but we think we can predict the entire planets ecosystem changes? I also think we need to seperate out how humans are driving species extinct, and climate change. These two can be very different things, yet are always conflated in the media for hype. Most species are going extinct because their habitats are actively destroyed by humans, or are fished to extinction, not because the planet is warming.

jeffbee 5y ago
Predicting aggregate impacts of a warm climate decade into the future is far easier than predicting the short-term process of an unstable system hypersensitive to initial conditions.
- darkerside 5y ago
  Only in that you don't know you're wrong for a much longer period of time.
- throwaways885 5y ago
  As a layman, can you explain to me why a very accurate (i.e. small error) model wouldn't still lead to catastrophically incorrect results when projected across a long timespan?
  - jeffbee 5y ago
    There's a difference between a fairly simple linear model of the climate and trying to guess whether the initial conditions of an unstable disease propagation model are < 1.0 or > 1.0. Think of climate modeling as saying that for a given species of trees, half of them will be dead at a given latitude in 50-100 years, not pointing at a specific tree and predicting that it will die on July 7th, 2047.
  - jbay808 5y ago
    What do you consider to be catastrophically incorrect? If the model predicts that a glacier disappears in 2050 and it disappears in 2070 instead? Or if the lack-of-model makes a lack-of-prediction about glacier disappearance, and then it disappears in 2070 by surprise? Error accumulation makes sense to worry about if you're planning a voyage and worried that dead-reckoning navigation will leave you kilometres off course. But if you're on the voyage already, out on the open ocean, you can argue with the navigator's math but you still need to navigate -- you won't do better by just blindly insisting the boat never left the harbour.
adamrezich 5y ago
ever since I read this article titled "Clouds May Be the Key to a Climate Modeling Mystery"[0], I've come to understand that all climate models are basically useless for predicting anything. anyone who claims such-and-such will happen as a result of climate change, because a model said so, is speaking nonsense. the planet is massive and its climate is an infinitely fractally complex system. if we can't even model clouds with anything remotely resembling accuracy, then why do we put any stock in predictive climate models at all? basically everyone agrees that the climate is changing, has always changed, and will always change. there is debate over how much of climate change is anthropogenic, but this is irrelevant to the point that predictive climate models are functionally useless, due to the complexity of the thing it's modeling. [0] https://www.scientificamerican.com/article/clouds-may-be-the-key-to-a-climate-modeling-mystery/ https://www.scientificamerican.com/article/clouds-may-be-the... downvoters: I would appreciate an explanation as to how my understanding of this situation is inaccurate. my views are never set in stone, I'm always open to learn new things. I just don't see how, short of a complete holistic Matrix-style simulation of the planet, one can obtain meaningful predictions from a data-driven climate model. I'm wrong about a lot of stuff all the time and I'd like to know where my understanding of this situation is incomplete or inaccurate.
- vegetablepotpie 5y ago
  > climate models are basically useless for predicting anything That is false. Although you’re correct that climate is very complex and it is impossible to model every detail. The notion that you cannot make valid conclusions from modeling because a set of observations do not match models is fallacious because it discounts the correct conclusions that climate models have achieved. For example, the first climate models from the 1960s predicted that the mesosphere will contract and cool as a result of increasing co2 concentrations, and this conclusion has been backed by empirical observations. Furthermore, modeling from the 1970s by scientists at Exxon Mobile found that by 2020, net warming would reach an average of 1 degree centigrade, which we’ve since exceeded.
  - adamrezich 5y ago
    how is this different than a broken clock being correct twice a day? by this I mean to say, just because some predictions made using some models turned out to be correct, why does this validate those or all climate models as accurate predictors of the future? the system is so complex, poorly-understood, infinitely fractal, with endless variables depending upon each other in ways that we mostly don't understand... the models are so varied, based on different data sources, some omitting entire classes of data entirely... I would be more surprised if some predictions some models made didn't end up being true after several years. but that doesn't mean they're useful at predicting things going forward, by any means.

by zpeti 5y ago

jeffbee 5y ago

Predicting aggregate impacts of a warm climate decade into the future is far easier than predicting the short-term process of an unstable system hypersensitive to initial conditions.

darkerside 5y ago
Only in that you don't know you're wrong for a much longer period of time.
throwaways885 5y ago
As a layman, can you explain to me why a very accurate (i.e. small error) model wouldn't still lead to catastrophically incorrect results when projected across a long timespan?
- jeffbee 5y ago
  There's a difference between a fairly simple linear model of the climate and trying to guess whether the initial conditions of an unstable disease propagation model are < 1.0 or > 1.0. Think of climate modeling as saying that for a given species of trees, half of them will be dead at a given latitude in 50-100 years, not pointing at a specific tree and predicting that it will die on July 7th, 2047.
- jbay808 5y ago
  What do you consider to be catastrophically incorrect? If the model predicts that a glacier disappears in 2050 and it disappears in 2070 instead? Or if the lack-of-model makes a lack-of-prediction about glacier disappearance, and then it disappears in 2070 by surprise? Error accumulation makes sense to worry about if you're planning a voyage and worried that dead-reckoning navigation will leave you kilometres off course. But if you're on the voyage already, out on the open ocean, you can argue with the navigator's math but you still need to navigate -- you won't do better by just blindly insisting the boat never left the harbour.

adamrezich 5y ago

ever since I read this article titled "Clouds May Be the Key to a Climate Modeling Mystery"[0], I've come to understand that all climate models are basically useless for predicting anything. anyone who claims such-and-such will happen as a result of climate change, because a model said so, is speaking nonsense. the planet is massive and its climate is an infinitely fractally complex system. if we can't even model clouds with anything remotely resembling accuracy, then why do we put any stock in predictive climate models at all? basically everyone agrees that the climate is changing, has always changed, and will always change. there is debate over how much of climate change is anthropogenic, but this is irrelevant to the point that predictive climate models are functionally useless, due to the complexity of the thing it's modeling. [0] https://www.scientificamerican.com/article/clouds-may-be-the-key-to-a-climate-modeling-mystery/ https://www.scientificamerican.com/article/clouds-may-be-the... downvoters: I would appreciate an explanation as to how my understanding of this situation is inaccurate. my views are never set in stone, I'm always open to learn new things. I just don't see how, short of a complete holistic Matrix-style simulation of the planet, one can obtain meaningful predictions from a data-driven climate model. I'm wrong about a lot of stuff all the time and I'd like to know where my understanding of this situation is incomplete or inaccurate.

vegetablepotpie 5y ago
> climate models are basically useless for predicting anything That is false. Although you’re correct that climate is very complex and it is impossible to model every detail. The notion that you cannot make valid conclusions from modeling because a set of observations do not match models is fallacious because it discounts the correct conclusions that climate models have achieved. For example, the first climate models from the 1960s predicted that the mesosphere will contract and cool as a result of increasing co2 concentrations, and this conclusion has been backed by empirical observations. Furthermore, modeling from the 1970s by scientists at Exxon Mobile found that by 2020, net warming would reach an average of 1 degree centigrade, which we’ve since exceeded.
- adamrezich 5y ago
  how is this different than a broken clock being correct twice a day? by this I mean to say, just because some predictions made using some models turned out to be correct, why does this validate those or all climate models as accurate predictors of the future? the system is so complex, poorly-understood, infinitely fractal, with endless variables depending upon each other in ways that we mostly don't understand... the models are so varied, based on different data sources, some omitting entire classes of data entirely... I would be more surprised if some predictions some models made didn't end up being true after several years. but that doesn't mean they're useful at predicting things going forward, by any means.