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How Climate Scenarios Lost Touch with Reality

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Re: How Climate Scenarios Lost Touch with Reality

#41
post #31

Eeh. Misguided article. The article itself starts by recognizing the challenge of making scenarios because of the feedback loop they embody. Then seemingly forgets about all that and basically says "coal has likely peaked already, why are assuming it will grow in the future?" Well, because of that feedback loop. Coal is still a cheap way of making energy, as it is in the business-as-usual economics of the scenarios.…

The IPCC report made some really questionable assumptions, reached conclusions based on those, which were then exacerbated by the journalists treating the worst case scenarios as absolute certainties. Creating fear and panic around stuff usually works and has worked well for a long time.

It's true that we reduced the usage of coal in last few years. It's a big assumption that it happened because of a worst case scenario popularized by IPCC.

From this article[1], IPCC's 8.5 was based on the assumption that between 2017-2100 we will use 5x as much coal as we had done in our entire lifetime. That's a like a "coal boom". The world was already moving away from coal, even before the report, and at best the report and faulty scenario created more panic.

> Everyone knew about the decades of coal-powered economic growth in China, but those working closely on the future of energy had already grown somewhat skeptical that the same model would be deployed across the developing world — and even more skeptical that the rich nations of the world would ever return to coal in a sustained way.

> The most conspicuous example was an emissions pathway called RCP8.5, which required at least a fivefold growth of coal use over the course of the 21st century. Because it was the darkest available do-nothing path, RCP8.5 was reflexively called, in the scientific literature and by journalists covering it, “business as usual.”

Feedback loop as you call it probably slowed down the pace turning the whole thing into a culture war, creating mass hysteria, and getting people to fight each other when they were likely already moving away from coal. We don't have a control group in this case, and climate action is needed, though I am not sure if creating panic was justified at any time.

[1]: https://www.nytimes.com/interactive/2022/10/26/magazine/clim...

Re: How Climate Scenarios Lost Touch with Reality

#42

Earlier quoted context omitted.

Please don't. Anyone on HN who wants a ChatGPT summary can make one themselves; when I read a person's post I want to know what that person has to say about a topic, not what they can produce with a machine. It's the same reason we don't need comments along the lines of 'I used a spell checker to identify the typos in your comment' or consisting of tables generated in MS Excel. edit: it's not due to any antipathy to…

Still upset about Wikipedia too?

Wikipedia is authored and curated by people who, by and large, know what they're talking about. When they make things up, it's verified and corrected by other people, usually within the decade.

Re: How Climate Scenarios Lost Touch with Reality

#43
post #35

How accurate are models of complex systems? Consider that if highly accurate models were really possible someone could make one that would accurately predict NFL game outcomes. When that happens we will know it because Sports Books would no longer take bets on NFL games. Sports Books profit because they get a slight statistical advantage which pays off due to bettor volume. So we know they can't make an accurately pr…

I'm sorry, but the sports betting analogy is hilariously wrongheaded. In order to set any prices at all, books have reasonably good models for the sports they offer, including NFL. But these models are not and do not need to be perfect, in order for a profitable business model to exist. There are in fact, plenty of "sharps" who can beat the books on certain sports or certain types of markets (e.g. maybe you can model O/U markets very well, but money line not so much).

The book does not "stop taking bets" on the entire event in question. The book simply has to limit the "sharp" individually. Of course then we get into the whole cat and mouse game of chasing sharp action through straw bettors and playing games of information theory (i.e. how much money can a sharp win while still plausibly not outing themselves as an obvious sharp).

The book only would have a serious problem, if the entire world became sharp and every bettor was betting sharply. But alas there you have a paradox: anyone who is currently a sharp, has a strong self interest to preserve the secrecy of their models and methods, because knowing something that nobody else knows is precisely what creates their edge. And so therefore, as long as sharps have this self-interest, then there is no problem for books to keep operating, and the problem is reduced to one of identifying and limiting sharps occasionally (basically a "cost of doing business" that books acknowledge).

The only way for the scenario you describe to happen, is for disinterested actors with no thought of profit for themselves, to not only "solve" a particular market, but also release it to the entire world and make it a commodity. I'm not saying it's impossible, but I'm saying that normal economic incentives work against this outcome.

Re: How Climate Scenarios Lost Touch with Reality

#44
post #27

I'm not clear on the take away. Are the models wrong? Or is it more that the projections were off? Put differently, are the models precise but inaccurate or both? If inaccurate only, are they still instructive?

The article argues that the models are still using baselines from the 90s, while the world as it is today has already made significant progress toward decarbonizing industry. Therefore the projection are far more onerous than they should be.

[deleted]

Re: How Climate Scenarios Lost Touch with Reality

#45
post #35

How accurate are models of complex systems? Consider that if highly accurate models were really possible someone could make one that would accurately predict NFL game outcomes. When that happens we will know it because Sports Books would no longer take bets on NFL games. Sports Books profit because they get a slight statistical advantage which pays off due to bettor volume. So we know they can't make an accurately pr…

> How accurate can they possibly get with climate change modeling?

At least as accurate as weather reports, which can be pretty reliable days in advance. The outcome of a football match often can't be predicted accurately during the match. This should suggest that the atmosphere and a sport are qualitatively different things.

> What happens if they say the climate is fine?

They go into some other statistical modelling field, probably to do with meteorology, and we start to get accurate weather reports two weeks in advance.

It's not like high-level sports players, who have specialised into that sport, and are unlikely to ever be high-level players of any other sport. (If anything, there are incentives for high-level sports players to throw games to keep them more exciting! Maybe that's why we can't predict the games? It's not, but what if it were?)

Re: How Climate Scenarios Lost Touch with Reality

#46
post #35

How accurate are models of complex systems? Consider that if highly accurate models were really possible someone could make one that would accurately predict NFL game outcomes. When that happens we will know it because Sports Books would no longer take bets on NFL games. Sports Books profit because they get a slight statistical advantage which pays off due to bettor volume. So we know they can't make an accurately pr…

I cant tell whether the parent comment is disingenuous though it looks a lot like it, but I will take it at face value.

The models created by the oil companies back in the 70s seem to be “breathtakingly accurate” [1]

Second, the problem with your analogy is that with football you expect the prediction to be X team will win, and similarly expect the predictions to be X weather event at $place will occur. The problem with your expectations of predictions regarding the latter is the sample space.

The sample space is so large that extreme weather events will occur $somewhere. Predicting exactly where and their trajectories is difficult due to chaos and the complexity of the system. There is a bound on our capacity to predict exact events long ahead of time. However, what we can do is give a probability of the event occurring over a large enough region. When you scale said region to the earth, we can ignore very small details and focus on the bigger picture, which is that the variance in weather in creases.

The problem with an increasing variance is that extreme events occur more frequently in all directions. Meaning high and low temperatures, droughts and floods and so on.

To observe this in action, a year or so ago europe had severe floods that killed many people and simultaneously over the next summer experienced historic droughts.

The sample space strikes again and we saw historic droughts in China too.

[1] https://www.theguardian.com/business/2023/jan/12/exxon-clima...

[2] Firmament, by Dr Simon Clark

Re: How Climate Scenarios Lost Touch with Reality

#47
post #27

I'm not clear on the take away. Are the models wrong? Or is it more that the projections were off? Put differently, are the models precise but inaccurate or both? If inaccurate only, are they still instructive?

The article argues that the models are still using baselines from the 90s, while the world as it is today has already made significant progress toward decarbonizing industry. Therefore the projection are far more onerous than they should be.

We're probably using more carbon now, then in the 90s. You have to look at the total carbon output of the world.

Re: How Climate Scenarios Lost Touch with Reality

#50
The problem with scenarios is that every resource is entangled with many others and that evolution of each one is wildly non-linear. Example : copper availability depends upon energy availability. However sustainable energy deployment depends upon copper extraction (as long as we're in the "up" part of the development S-curve).

Another less important example is helium : helium is necessary for high end electronics, and electronics are necessary for modern cars. However car manufacturers are generally completely oblivious of their very real dependency upon helium, which came mostly from the US and Russia.

I've just watched an interesting conference by a researcher who's working on new, complex models to build scenarios taking all these entanglements into account, managing thousands of different resources across the whole globe. At the moment there's like 5 of them working on these. Unsurprisingly, these complex, stochastic models treated with lot of Monte-Carlo analyses and now even AI are far from being stable and precise enough for projects such as IPCC. So that's where we are for now.

Classical economics are wildly out of touch with reality here (Nordhaus even got the Nobel in economics with a completely bonkers linear extrapolation of climate effect on global GDP), and these sorts of interdependencies are everywhere.

So OK, I've got it, the scenarios are too simple. But the IPCC working group II is composed of mainstream economists, and mainstream economists are wildly out of their league (in my opinion I'd go as far as saying that macro economy is a pseudo-science at this point anyway), so they're doing what's possible in a mainstream environment. Too bad.

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