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

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

#132

Earlier quoted context omitted.

It’s not the case. Newsweek has a cover story. None of the consensus of climate science said anything about an ice age. The anti-warming FUD spreaders use this debunked claim to press their lies.

It wasn't just a Newsweek cover story. There were still major news cycles on the coming ice age in the early 80's.

Bad science reporting is not the same thing as science. Major news cycles were misreporting the actual science. No science was predicting a coming ice age in the 80s.

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

#133
post #83

Earlier quoted context omitted.

What about the person who believes in anthropogenic climate change but doesn’t believe that humans will ever be able (or have ever been able) to cooperate to the extent that is necessary to prevent it, and questions whether required technological advances will ever be made? Asking for a friend...

It’s not the cooperation that’s the issue. Every country can come together for the Olympics. It’s the cost. Green energy and co2 emissions reduction needs to have a cheaper price point to be globally adopted. If being green meant being more efficient and cost reduction it would be a no brainer. This is the challenge of green tech. We have to create the alternative. No one is willing to jump in a lifeboat made out of…

> It’s not the cooperation that’s the issue. Every country can come together for the Olympics.

It has been repeatedly demonstrated that countries can come together for the Olympics. It has yet to be demonstrated that they can do the same to fight global climate change. The opposite seems to be the case so far, as far as I can tell.

> The method of guilting people into changing makes me sick.

100% agree.

> Politics isn’t how we will get out of this, imho. Science and engineering is the key.

To move forward, we are going to need both science and engineering, and some minimum level of agreement in Democratic countries. Perhaps if we could manage that, China might consider getting on board as well.

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

#134

Earlier quoted context omitted.

It wasn't just a Newsweek cover story. There were still major news cycles on the coming ice age in the early 80's.

The ice age hysteria was big in the 70s as well. I don't know what year it started but 70s through 80s climate scientists were saying a global ice age was all but certain, based on sound science and those who disagreed were science haters and all around bad people. Interesting the guy noting this historical fact above has been flagged and censored and this subthread removed. The truth isn't allowed to be known on HN.

Citation needed.

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

#135
post #87
post #75

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I don't think there's any disputing the overall trendline, which far predates the Industrial Revolution. Yet that doesn't mean that human activity isn't also meaningfully impactful. Though it's hardly scientific, from a layperson's perspective, I find xkcd's climate history megacomic instructive: https://xkcd.com/1732/ . That rapid-ish spike after 1900 is by no means a smoking gun, but it's a hint that there may be m…

I'm mostly concerned about the scale were looking at. A 50-100 year uptick is nothing on the timescales that the planet operates on. Even 20k years is miniscule.

No dispute. And yet, I don't see any other instances of the a near-45-degree angle spike over the last 20k years (with the obvious caveat that our data on the past is imperfect).

Like I said, not a smoking gun; just a clue that it's worth digging into. And from a Bayesian perspective, one must ask: what are the odds that that rising temperature would happen to correlate with CO2, for entirely unrelated reasons? https://www.youtube.com/watch?v=Sme8WQ4Wb5w

Don't get me wrong, I find Greta-style alarmism and claims of "extinction" to be counter-productive. But given how difficult it is to get nerds to agree on anything, the fact that there are so few credible scientists on the other side of the issue gives me pause. Pure groupthink? Maybe. Hardly unprecedented. But we've been examining the data and improving the models for decades (including from those with a strong financial incentive to debunk AGW), and yet the scientific consensus continues trending in one direction. Skepticism is a good thing, but the evidence for AGW can't merely be handwaved away by causal narrative.

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

#136

Earlier quoted context omitted.

Nah. In 1974 and 1975, Time and Newsweek respectively ran articles proposing a global cooling trend. These articles were (loosely) based on a couple of papers that found that if fine-particulate atmospheric aerosols continued to increase the way they were, they could reflect away enough sunlight to cause surface cooling. (And in fact, exactly that was happening during the 70s.) However, the Clean Air Act and other si…

> the Clean Air Act and other similar efforts around the world reduced the amount of particulate aerosols in the air. You just found a solution to global warming. Since you agree that particulate aerosols in the air were going to cause an ice age and the Clean Air Act would fix that, then the Clean Air Act is what has contributed more than anything else to global warming. Repeal the Clean Air Act, reintroduce those o…

Sure. Now do the math on how much it will cost to make the aerosols and how many deaths due to respiratory illness it will cause.

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

#137
post #116

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The bias I'm suggesting is an appeal to authority, and you'll have to be more clear on how I'm displaying that, since I am neither suggesting I am an expert, nor am I showing off my long history of "being right" about other things.

It's not an appeal to authority when they back it up with data and numerical analysis.

You can back up study X with all the data and numerical analysis in the world, and it still doesn't increase study Y being right, except through appeal to authority.

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

#138
post #70

Earlier quoted context omitted.

It’s _nearly_ an urban myth. Some people did say we were due an ice age, but in the “within the next few millennia” range of accuracy, not ‘any day now’. Basically, it’s a good story, but that’s all.

"Meteorologists disagree about the cause and extent of the cooling trend, as well as over its specific impact on local weather conditions. But they are almost unanimous in the view that the trend will reduce agricultural productivity for the rest of the century. ... If the climatic change is as profound as some of the pessimists fear, the resulting famines could be catastrophic. ``A major climatic change would force…

Meteorologists are not, and have never been, scientists. Their opinion on climate is no more valid than any other lay persons. It is like equating the physicists and engineers who develop new MRI machines with the technicians who press the button at the imaging center. Time and Newsweek are not scientific sources. Your whole post is just nonsense.

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

#139
post #63
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…

Your comment contains hypotheticals ("run random models and wait long enough you will always be able to find at least one model that predicted the current observations") that are NOT what the present study did. As noted in TFA, they looked at 17 forecasts from 14 models and found that the temperature predictions of 10 of them were consistent with what has happened in the meantime. And if you adjust for forcing (CO2,…

But we don't know how those 17 were chosen in the first place. There would be survivorship bias if models which match observations get more attention.

With that being said, I doubt that survivorship bias is strong enough to explain their combined result of 10/17 models being significant.

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

#140
post #63

Earlier quoted context omitted.

Your comment contains hypotheticals ("run random models and wait long enough you will always be able to find at least one model that predicted the current observations") that are NOT what the present study did. As noted in TFA, they looked at 17 forecasts from 14 models and found that the temperature predictions of 10 of them were consistent with what has happened in the meantime. And if you adjust for forcing (CO2,…

> As noted in TFA, they looked at 17 forecasts from 14 models Pardon a little pedantry: >> The researchers compared annual average surface temperatures across the globe to the surface temperatures predicted in 17 forecasts. Those predictions were drawn from 14 separate computer models released between 1970 and 2001. In some cases, the studies and their computer codes were so old that the team had to extract data publ…

Even if they said how many models they looked at before choosing 14 models (and explained why they chose those 14), conspiracy theorists and people skepticalof climate science would still argue that it is not legitimate because of survivorship bias and several other reasons.

"You looked at 1000 models, but what about the 1000 models that scientists made and didn't publish. You didn't look at those!"

People can always suggest more tests you need to do or poke holes in any analysis. That doesn't mean you just stop ding the work.

Overall it is impressive that different models made over 30 years can predict fairly accurate results. In my opinion that shows that the underlying physics of the models is correct and makes me trust the models even more.

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