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Even 50-year-old climate models correctly predicted global warming

sciencemag.org

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Re: Even 50-year-old climate models correctly predicted global warming

#51

Post by huffmsa »

aidenn0 wrote: post #42
jml7c5 wrote: post #29

I'm not sure if he'll pop in here, but one of the co-authors (Henri Drake) has a comment thread on /r/science if anyone wants to ask any questions: https://www.reddit.com/r/science/comments/e63ic5/of_17_clima... EDIT: Here is some of the code used in the paper: https://github.com/hausfath/OldModels Here is a blog post on the paper, written by one of the authors: http://www.realclimate.org/index.php/archives/2019/12/h…

When Henri was suggesting to use specific models for specific predictions, he added this note: > Note to reader: I was going to use Arctic sea ice in 2100 as an example, but there probably won’t be any lol

There has been sea ice in the Arctic for well under 50% of the planets history.

Life thrived

The Sahara desert was a grassland 5000-10000 years

Life thrived.

Re: Even 50-year-old climate models correctly predicted global warming

#53

Post by bitlax »

woodandsteel wrote: post #36

Standard conservative responses: --The globe is not getting warmer --We don't know if the globe is getting warmer or not --We do know the globe is getting warmer, but we don't know why --We do know the globe is getting warmer, but it has a different cause than human activities --We do know the globe is getting warmer, and it is in part due to human activities, but any action to counter this would be more harmful than…

How do we convince China and India to lessen their CO2 production in any meaningful way?

Re: Even 50-year-old climate models correctly predicted global warming

#54

Post by starpilot »

It does seem like survivorship bias could be a factor. The article talks about how some of the old models were off until they "corrected" them. All right, and did they apply the same scrutiny to the apparently "correct" ones? "All of the models predicted this (except for the ones that didn't.)

Re: Even 50-year-old climate models correctly predicted global warming

#55

Post by gowld »

huffmsa wrote: post #51
aidenn0 wrote: post #42

Earlier quoted context omitted.

When Henri was suggesting to use specific models for specific predictions, he added this note: > Note to reader: I was going to use Arctic sea ice in 2100 as an example, but there probably won’t be any lol

There has been sea ice in the Arctic for well under 50% of the planets history. Life thrived The Sahara desert was a grassland 5000-10000 years Life thrived.

Most people are interested in a particular subset of life thriving.

Re: Even 50-year-old climate models correctly predicted global warming

#56

Post by lukifer »

bagacrap wrote: post #4
minikites wrote: post #2

People who don't believe in anthropogenic climate change at this point are no better than people who believe the Earth is flat.

I watched the documentary about flat Earthers and I think they're just having harmless fun.

I found the same documentary instructive. I think there's an insight there into human tribal instincts, demonstrating that our epistemologies can't help be be socially mediated. It was flabbergasting how deeply intelligent some of the true believers were, and it's a little too convenient to label and discard them as crazies or outliers. They might be a little more representative of the human animal than any of us want to admit.

What's most unsettling is, there's no reason to expect that the same psychosocial tribal mechanisms are not constantly active, even when the facts are on the side of one's tribal beliefs. This leads to any number of blind spots, not only in truth-seeking and self-correction, but in social dynamics (in-group vs. out-group). Our brains are exceptionally, insidiously good at working backwards, not just to convince others, but to convince ourselves. Those who can spin on a dime and update/discard ideas in the presence of new evidence are a truly rare breed.

Two of my favorite books on motivated reasoning and self-deception:

Strangers to Ourselves, by Timothy D. Wilson: https://www.hup.harvard.edu/catalog.php?isbn=9780674013827

The Elephant in the Brain, by Robin Hanson & Kevin Simler: http://elephantinthebrain.com/

Re: Even 50-year-old climate models correctly predicted global warming

#57

Post by p1necone »

huffmsa wrote: post #51
aidenn0 wrote: post #42

Earlier quoted context omitted.

When Henri was suggesting to use specific models for specific predictions, he added this note: > Note to reader: I was going to use Arctic sea ice in 2100 as an example, but there probably won’t be any lol

There has been sea ice in the Arctic for well under 50% of the planets history. Life thrived The Sahara desert was a grassland 5000-10000 years Life thrived.

https://xkcd.com/1732/

Re: Even 50-year-old climate models correctly predicted global warming

#58

Post by triceratops »

woodandsteel wrote: post #36

Standard conservative responses: --The globe is not getting warmer --We don't know if the globe is getting warmer or not --We do know the globe is getting warmer, but we don't know why --We do know the globe is getting warmer, but it has a different cause than human activities --We do know the globe is getting warmer, and it is in part due to human activities, but any action to counter this would be more harmful than…

[deleted]

Re: Even 50-year-old climate models correctly predicted global warming

#59

Post by starpilot »

ekianjo wrote: post #48

Where is the story hère though? So they looked retroactively and found some models in the past that fitted with current observations even though they had no clue that China would become such a powerful force in terms of CO2 emissions? If you run random models and wait long enough you will always be able to find at least one model that predicted the current observations. That does NOT mean the models were right, it me…

Yeah, this could be survivorship bias: https://motls.blogspot.com/2017/03/selection-of-climate-mode...

As someone who's written basic fluid dynamics codes, I'm blown away by the complexity of climate models. The errors I ran into in debugging my relatively straightforward codes were incredibly subtle. Like pressures, velocities still "looking right" but still being wrong, due to numerical viscosity and other artifacts of the inexact solutions to Navier-Stokes. This is for flow in a box in a steady state. For an entire planetary atmosphere at a time scale of decades, I can't even imagine how they can track down every error without duct taping "corrections" (overfitting) on everything.

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