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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

#91

Post by rayiner »

claudeganon wrote: post #84
rayiner wrote: post #77

Earlier quoted context omitted.

Even a 5C (9F) warming is not "CATASTROPHE." See: https://www.forbes.com/sites/ucenergy/2018/12/05/will-global... > While it is true that we estimated damages as high as 10% of GDP annually at the end of the century for warming of 15°F above pre-industrial levels, the odds of a temperature change that would drive damages of this magnitude are slim. In fact, they are less than 1-in-100 by our original calculation. Und…

Not a catastrophe for whom is the obvious question here.

Pretty much everybody: https://www.cnbc.com/2019/08/20/climate-change-to-slow-globa...

> In other words, if global GDP doubles or halves by 2100, the results suggest real GDP per capita would still be 7.22% below where it would be otherwise.

For most of the world, an RCP8.5 scenario is equivalent to knocking out 3-4 years of GDP growth. Bad, but not catastrophic, and probably less bad than the impact of "WWII-style mobilization" and shifting the economy into command-and-control mode.

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

#92

Post by Angostura »

leifdenby wrote: post #47

There is a big observational campaign happening right now that is trying to get to the heart of this called EUREC4A (main website: http://eurec4a.eu and information sheet: http://eurec4a.eu/fileadmin/user_upload/eurec4a/2019/Press/E... ). The key uncertainty between different climate models is whether shallow clouds in the tropics (which in general cool the Earth through radiation) will disappear or not and make our…

I suppose my immediate question is - is there any way for an non-professional with a pair of eyes and a smartphone to contribute in a crowd-sourcy way?

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

#93

Post by HenryKissinger »

jokoon wrote: post #90

I live in a small, old apartment in the EU, without proper AC. I'm pretty worried about the next summer. I can crash at a friend where the temperature never went above 26C last summer, despite a heatwave. I always hope that if heatwaves keep coming summer after summer, governments/the UN will take tough decisions. If nothing is done and summers are too hot, I clearly see people protesting/striking/blocking roads/etc…

You should get an AC unit. A window one if you have the right kind of window, or a larger, mobile one.

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

#94

Post by cat199 »

fabian2k wrote: post #10

The title seems like clickbait, and the last part of the article does explain that the scientists actually know that new cloud models are mostly responsible for the change. The big question is then of course whether the new cloud model is wrong and the temperature increase therefore as well, or whether the new cloud model is more accurate than previous ones and the temperature increase is a real effect. I found anoth…

> The title seems like clickbait

Not to diverge, but I'd be extremely wary of editorial bias/spin from this particular publication until November or so.. which is not to say that the topic itself is suspect - as you point out, the big question is if the updated model is actually worse than previous models or if it is better

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

#95

Post by microcolonel »

Udik wrote: post #88
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…

Total wars are not known to increase the quality of life. If a transition to a green economy guaranteed such massive economic gains (and no pains) don't you think that politicians of all colours would scramble to implement it? The first step to solving issues is to acknowledge all the difficulties that lie ahead: otherwise you end up in a delusional state in which solutions are obvious and easy and the only reason th…

The other sad conclusion to derive from this is that the "improvements to urban planning" bit is largely not happening, despite generally broad bipartisan support.

It signals to me that people like complaining about things, but do not participate in politics in any productive fashion. Right now it's just team sports, and most people can not name the candidate they are voting for, outside of the presidential election, until they read it off the ballot.

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

#96

Post by peterwoerner »

norswap wrote: post #6
vincent-toups wrote: post #2

I guess climate scientists don't use version control?

The article isn't very precise, but my understanding was that the run some kind of machine learning based on past data. Adding in the more recent data changed the predictions dramatically. So it's not an issue of versioning (I assume they could reproduce the old results using the old data).

They technically use the term constitutive model development. The math is similar to machine learning.

Typically we know the basics of the physics, i.e. conservation of energy, momentum and angular momentum which set up the equations. But there a number of constitutive laws which relate parameters between these are "machine learned" but in generally, they are typically linear relations.

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

#98

Post by AsusFan »

chrisco255 wrote: post #63
DennisP wrote: post #42

Earlier quoted context omitted.

People use models to try to nail down the details, not to see whether climate change from CO2 emissions is a real thing. That's well established by physics and geological history. A good presentation of this evidence is in a couple chapters of Hansen's Storms of My Grandchildren .

Could you point me to the academic, empirical research that quantifies the influence of CO2 on climate? Not a book, but from an academic publication.

Assuming that you asking honestly, and not just trying to derail the conversation...

Start here: https://skepticalscience.com/empirical-evidence-for-co2-enha...

Then proceed to intermediate and advanced. There are a TON of citations for your perusal. After your are done with that, the comments have some additional insights.

Have fun. This is quite the rabbit hole to dive into.

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