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Climate models are running red hot, and scientists don’t know why

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Re: Climate models are running red hot, and scientists don’t know why

#141

Post by dls2016 »

Angostura wrote: post #104
dls2016 wrote: post #71

Earlier quoted context omitted.

This part of climate "science" always makes me put on my Popper hat. The social aspect of being the outlier (grants dry up, career goes away) makes me skeptical of the IPCC reports, just not in the usual direction. I fear reality could be much worse. I can't ding the climate scientists too much, though... I'm not sure there's a better way to study this stuff.

In this case have grants actually dried up or careers gone away? Nope.

I don't think I implied they did. I'm only saying that humans are social creatures and that scientists are susceptible to peer pressure (even in "hard" sciences with lots of possibility for experiment). I imply no maliciousness, but am trying to voice my fear of the impossibility of knowing whether or not the consensus warming scenario is a "reversion to the social mean", that is, we just have to wait and see if warming is worse that expected.

But I'm only a bit surprised this would be such a controversial opinion here.

Re: Climate models are running red hot, and scientists don’t know why

#142

Post by cryptica »

Accujack wrote: post #66
klodolph wrote: post #22

Earlier quoted context omitted.

Or a third, frustrating possibility—the new cloud model is more accurate, but some other inaccuracy in the model used to be balanced out by the inaccurate cloud model.

Or that there are multiple inaccuracies in the model which interact, so finding and correcting each one makes progress but still doesn't improve the model overall.

Having built some models to simulate very basic things myself, I've seen first-hand how the slightest deviation of the model from reality can completely invalidate the entire output of the model.

For this reason, I'm skeptical of models that try to simulate very complex systems with a lot of variables and feedback loops. Models that have a large number of variables are particularly difficult to get right because different tiny mistakes in various parts of the model can compound and yield completely arbitrary and contradictory results. Approximating the reality in software is almost impossible.

Re: Climate models are running red hot, and scientists don’t know why

#143

Post by tasty_freeze »

protanopia wrote: post #69
orev wrote: post #37

Earlier quoted context omitted.

Tweaking the inputs would help one to identify what factor is causing the difference, which allows you to focus on that. It doesn’t mean you permanently leave it out. And it does not make a credibility issue. This is how science works — it is a process that strives to be as accurate as possible, not come up with a static answer and stick to it (that’s what religion does). The ability for science to change and adapt i…

It certainly does hurt the credibility of people saying we need drastic changes now based upon the models. If the answer might change next year, then making a drastic change based upon the current projections seems foolhardy.

Individuals, corporations, and the politicians who set policy all operate on imperfect knowledge in many many domains as a routine matter of course.

It is a denier talking point to claim that we just don't know enough, or that the models are always being tweaked and we should just wait until scientists have "the final answer" before doing anything.

Hey, let's stop giving NOAA weather forecasts because they aren't 100% accurate. Let's close down the stock market until everyone can decide what the values should be. Let's disband the military because not all military leaders have the same opinion.

If we are mature enough to recognize that imperfect but credible models are worth acting on in other domains, why do we hold climate change to impossible standards?

Re: Climate models are running red hot, and scientists don’t know why

#144

Post by [deleted] »

Certhas wrote: post #124
protanopia wrote: post #69

Earlier quoted context omitted.

It certainly does hurt the credibility of people saying we need drastic changes now based upon the models. If the answer might change next year, then making a drastic change based upon the current projections seems foolhardy.

FUD. The statement that we need drastic changes is not dependent on the details of the projection and is not based on it. Further, climate models have correctly predicted the heating we have already caused. We have known the rough level of the climate sensitivity (delta T per doubling CO2) in the current macro state for decades. We have observed it. This science is incredibly settled. We don't know where the tipping…

[deleted]

Re: Climate models are running red hot, and scientists don’t know why

#145

Post by 0xffff2 »

coldpie wrote: post #122
0xffff2 wrote: post #52

Earlier quoted context omitted.

There is a problem and you can't do anything about it. We are way past the point where individual action is going to cut it. You have to vote. No other action is going to have a meaningful impact and you shouldn't pretend otherwise because it makes you feel better about yourself.

You're right that individual action isn't enough. But individual action does also have an impact. Commuter cars and SUVs (not airplanes, not shipping trucks) are the largest single source of carbon emissions in the US[1], accounting for about 15% of all US carbon emissions[2]. If just 1 in 10 commuters switched to taking public transit instead of driving, that alone would drop US emissions by 1.5%. If public transit…

> If public transit became the default method for most transportation, we could realistically lop off 7-10% of US emissions.

I honestly struggle to understand this statement in the context of discussing individual action. Making public transit a reasonable option for most personal transportation in the US would be a public works project on the scale of the New Deal.

Perhaps more importantly, cutting US emissions by 10% is very nearly inconsequential unless it is part of a coordinated effort that is driving global emissions down by significantly more than 10%.

Re: Climate models are running red hot, and scientists don’t know why

#146

Post by Igelau »

TimTheTinker wrote: post #79
JackFr wrote: post #64

Earlier quoted context omitted.

> advances in computing have allowed the reduction of cell size, allowing more detailed and therefore hopefully more accurate physical simulations. 'Hopefully' is doing a lot of work there. In modeling a highly dimensional dynamic system it's not obvious that a smaller cell size will lead to more accurate predictions.

... beyond a certain (perhaps trivial or intuitive) threshold.

I guess that depends on the nature of the models. If they actually capture the inherent chaos of the system they claim to model, then minor tweaks will have wildly unpredictable side effects.

Re: Climate models are running red hot, and scientists don’t know why

#147

Post by bannable »

lazyjones wrote: post #50
jknoepfler wrote: post #35

Earlier quoted context omitted.

So if I asked you to bet at 50/50 odds that next year would be colder on average than this year, you'd take the bet?

That's not what climate is about. Also, it depends on location, in many places it was colder in 2019 than in 2018. If you're talking about some calculated "global" temperature, it doesn't exist in a valid form.

Are you claiming that it is not possible to find a trend in a mean temperature of a great many points across the globe, over a long period of time?

What makes such a measurement an "invalid form"?

Re: Climate models are running red hot, and scientists don’t know why

#148

Post by zaroth »

lucisferre wrote: post #87
protanopia wrote: post #69

Earlier quoted context omitted.

It certainly does hurt the credibility of people saying we need drastic changes now based upon the models. If the answer might change next year, then making a drastic change based upon the current projections seems foolhardy.

Yes it would be terribly foolhardy for us to stop polluting the atmosphere prematurely.

This isn’t really a helpful reply, because of course it’s not a question of magically reducing pollution.

There are two basic modes of reducing pollution. Technological advancement, and conservation.

In the case of technological advancement, you get less pollution per unit of output as the same or lower cost. As long as capital is fairly cheap, these advances tend to propagate quickly through a competitive market.

In the case of conservation, it’s more a question of which groups of people should conserve (i.e. suffer) for this outcome, and by how much.

Re: Climate models are running red hot, and scientists don’t know why

#149

Post by QuantumGood »

HenryKissinger wrote: post #65
derg wrote: post #19

Earlier quoted context omitted.

Can you even imagine how a Total War economy/society based on transitioning to greener energies, cutting emissions and pollutants, and working on improvements to housing and urban planning would end up looking? Like ignoring the whole climate change thing for a moment (though we absolutely should not do that), just the quality of life improvements to our health and well being this kind of mobilization would bring wou…

That would not be possible today. The wartime World War Two economy we learn about in school was only made possible because of two factors: 1) A massive surge in federal government spending, financed by borrowing from public markets (incl. war bonds), to buy the materiel needed to fight a war on two fronts (in Europe against Germany and in the Pacific against Japan). Such spending caused the public debt as a share of…

https://www.nytimes.com/interactive/2019/12/12/business/econ...

America has a large shadow labor force. People who do not regularly apply to work are not counted as officially “unemployed.” Have to take this into account.

Re: Climate models are running red hot, and scientists don’t know why

#150

Post by cagenut »

samatman wrote: post #129

I'm reminded of Feynman's famous anecdote about the Millikan oil drop experiment: Millikan underestimated the charge of the electron, and over the ensuing years, subsequent measurements slowly but surely converged on the correct value. Why? Because experimenters who got the correct value figured it must be too high, and ran the experiment again until they got a more-erroneous value, one that was nonetheless higher. E…

this is textbook middlebrow contrarianism.

using some quote from some recognizable name to dismiss the incredible work of dozens of top of their field professionals doing their life's work.

its a perfect example of the way hacker news "types" do climate change denial. via endless "well-actuallys" until you're lost and stuck in a level of analysis-paralysis that borders on an anxiety disorder.

the problem with solving climate change is not a technology problem any more, its a decision making and coordination problem. we have a third of people in denial, a third of people who want to fix stuff, and this unbelievably infuriating third of people in the middle who can't stop equivocating and triangulating.

the thing preventing a simple majority from moving on with solutions is not the outright-deniers, its the people in the middle using the deniers as an excuse to not get on board with the solvers.

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