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

bloomberg.com

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

#191

Post by Kliment »

derefr wrote: post #181
monkeynotes wrote: post #177

Earlier quoted context omitted.

Seems like a recipe for bad data and undiscoverable flaws.

Not really; you'd probably take the Folding@Home approach† to work distribution: assign each small piece as a job to N non-trustworthy "workers" (humans, computers), and then trust the results if all N results concur. If they don't, fail the job back into the work queue to be tried again later with different workers. (And maybe give the workers a reputation score, kicking out the ones who participate in enough failed…

Closest I can think of is https://en.wikipedia.org/wiki/Triple_modular_redundancy

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

#192

Post by qubex »

bumby wrote: post #185
qubex wrote: post #167

Earlier quoted context omitted.

Why do you want to a horde of “non-professional[s] with a pair of eyes and a smartphone” to contribute if literally hundreds of professionals with high-end equipment, meteorological observation satellites, and oodles of computational firepower are already on the task? The main problem has never been a lack of science, the problem has always been (and alas, continues to be) a lack of political wherewithal to actually…

I think what precedes the problem you mention (and one of the main points in the article) is the problem of generating reduced uncertainty in the model. Maybe there’s a chance for more granular data to enhance that?

The problem isn’t the granularity of observations, it’s the granularity of the grid with which the simulations are run. As I understand it (by analogy with my own field of macroeconomics) the current limit is the fact that the grid is coarser than the average size of a cloud, and that therefore cloud cover needs to be approximated. That is the real source of uncertainty.

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

#193

Post by fencepost »

lbsnake7 wrote: post #134
anonuser123456 wrote: post #103

Earlier quoted context omitted.

>I’m a climate change skeptic almost entirely because I don’t trust models. You don't have to believe the models: https://www.fooledbyrandomness.com/climateletter.pdf

My argument to this would be that changing our world because of a faulty model system would be disastrous. Because of the advancements of the last two centuries more people have had food and water and basic necessities being met then at any time in history (and yet we still have billions suffering). Worsening their lives over something that might not happen is not a good way to run the world. The models being accurat…

The models being accurate is important so that if we do implement policy that end up worsening people’s lives we have proof that it is worth it.

The models differ in the scale of how bad it's going to be, not on whether it's going to be bad. Your stance is kind of like saying "Well doc, you're telling me I have sepsis, but you can't tell me how bad that's going to be so I'm refusing treatment until you can improve your models."

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

#195

Post by luckylion »

giarc wrote: post #29

If you are like me, you hate reading articles like this. You know there is a problem but you feel like you can't do anything about it. You recycle, you turn off lights, you have a programmable thermostat but you know it's a drop in the ocean. I finally decided to do something about it last fall. I researched and have committed to purchasing green power. Every month I purchase 850 kWh for $22 from Bullfrog Power (a Ca…

> Every month I purchase 850 kWh for $22

Is there a typo somewhere? I run multiple computers at home 24/7 and I'm using ~2500 kWh a year. Also, 850 kWh for $22 sounds crazy cheap, I pay ~100€ per 200kWh (including the rented meter, but more importantly, taxes).

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

#196

Post by marmaduke »

qubex wrote: post #187
mondoshawan wrote: post #139

Earlier quoted context omitted.

Can we get the source for the models?

http://www.cesm.ucar.edu/models/ccsm4.0/ seems to offer what you are looking for (first Google hit for “NCAR climate model source code”) but without a cluster of supercomputing nodes, what are you planning to do with it?

ESCM is a smaller one and it seems there are transport matrix models which could be small enough for a single workstation?

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

#197

Post by samatman »

jellicle wrote: post #180
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…

So close, but not quite. The oil drop results (Millikan was less than 1% off, by the way) show the pressure on scientists to conform with the current status quo, the pressure NOT to release shocking or unexpected results. In climate science, that means underplaying the results, biasing them towards less catastrophic findings, and there's a great deal of evidence that that is what has been happening. For instance, the…

I've read the AR5 synthesis report, and your description is simply inaccurate.

To use your numbers, the IPCC reports that 99% of scientists believe 100 units of climate change is coming, and 1% believe no more than 30.

It's less than 200 pages, I recommend actually reading it, rather than just guessing how the sausage is made, as you've done here.

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

#198

Post by shusson »

cryptica wrote: post #142
Accujack wrote: post #66

Earlier quoted context omitted.

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 diff…

I believe you are talking about Chaos theory [1]

[1] https://en.wikipedia.org/wiki/Chaos_theory

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

#200

Post by protanopia »

bannable wrote: post #151
protanopia wrote: post #119

Earlier quoted context omitted.

Are you asking about the weather in one specific year? Weather is not climate.

Yes, weather is climate. But that isn't what OP said.

Climate is long term patterns. Weather is what is happening at a specific time. If the distinction wasn't made then someone could argue that a cold winter day disproves warming.
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