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The computer models (all models are wrong, some models are useful) 7

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GregLocock

Automotive
Apr 10, 2001
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Orbiting a small yellow star
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One problem with concentrating on the global average temperature as the taregt for testing the fidelity of the models is that local effects can be wildly out of whack. In particular in this case the temperature during the growing season for corn is of significance to farmers, yet the computer models get it wrong


Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376
 
...ever hear of Lorenz's butterfly? Climate models are extremely complex and subject to perturbations... one of the problems in guessing the weather a week from now...

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik
 
dik said:
...ever hear of Lorenz's butterfly? Climate models are extremely complex and subject to perturbations... one of the problems in guessing the weather a week from now...

I don't know if I've ever seen a more ironic post. That's exactly the point. It seems that climate change is much bigger than CO2. CO2 and this per capita nonsense exists only to convince the West to suicide itself.
 
It's an effect of CO[sub]2[/sub]. It's not a myth and is not nonsense. There's a direct correlation between CO[sub]2[/sub] and the earth's temperature. From where I'm sitting it's going to get a lot worse, but we'll have to wait and see. The next couple of years can be interesting.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik
 
"As I mentioned, it's happening." ... something's happening.

"It's an effect of CO2. It's not a myth and is not nonsense. There's a direct correlation between CO2 and the earth's temperature." ... this statement is why so much ink has been spilt. We KNOW so very little about the earth's climate that to say A is causing B is IMHO the height of hubris. Every time we learn something, we find a dozen other questions we don't know. But to say we do nothing until we KNOW is equally foolish.

The problem is that to "correct" CO2 is going to take such a massive cultural change and financial cost that people have had to say A is causing B, there's no doubt, and we're utterly domed if we don't do C. There's no "may" (in that A may be causing B), 'cause that opens the door to the how "how much ?" question. And the argument has ratchetted up so much that dire threats are posited (like "the globe will be uninhabitable by 2050 if we carry on"). The rhetoric is (IMHO) so absorb as people are saying things like "the tipping point is only 2030, after that we're doomed to an imminent and irreversible change".

And now we have a neat, catchy, slogan "net zero by 2050".

In my mind it is more like "A may be causing B" so lets look into A. Let's look into the climate mechanisms. Maybe we should stop burning coal (ok, well, reduce coal consumption), maybe there are some industries that liberate a lot of CO2, and maybe these can be modified at some acceptable cost ? Maybe there are things we can do that reduce CO2 without causing the destruction of our economies. Maybe build some more nukes ?

We should of course be aware of our impact on the environment. I contend that there are may more impacts than CO2, and by focusing in on one issue we're forgetting the others that could have a similar extinctual consequence.

"Hoffen wir mal, dass alles gut geht !"
General Paulus, Nov 1942, outside Stalingrad after the launch of Operation Uranus.
 

That part is 'bang on' and very serious, and therein lies the problem. People are using the uncertainty to defer trying to solve the problem. What are you trying to define here? And A is producing more CO[sub]2[/sub] than we are, or at least we will argue about it, instead of fixing it. We'll use metrics so we don't look so bad. All sorts of excuses.

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik
 

"An international team of scientists from the Earth Commission, of which we were part, identified eight “safe” and “just” boundaries spanning five vital planetary systems: climate change, the biosphere, freshwater, nutrient use in fertilizers, and air pollution."


-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik
 
geeze ... that is just word salad of just about the worst kind. who are these guys to decide what is "just", "safe" ? who are these guys to decide where we are on their arbitrary scale of doom ? was there Ever a chance that they would have said "job well done" ? Where to they measure things like human age/longevity ? economic benefits (%age below the poverty line) %age of humans with access to clean water ? power ? the internet ? authoritarian governments ? education/literacy ?

"Hoffen wir mal, dass alles gut geht !"
General Paulus, Nov 1942, outside Stalingrad after the launch of Operation Uranus.
 
Some people thrive on word salad. Then there are some of us who like a bit of animal protein.
 
Hmm, climate models don't obey the laws of thermodynamics, particularly #1


Long story short, they inject energy into the system beyond what the inputs are. Oh, I wonder why they run hot?

ABSTRACT: Coupledclimatemodelsareproneto‘‘drift’’(long-termunforcedtrendsinstatevariables)duetoincompletespinup and nonclosure of the global mass and energy budgets. Here we assess model drift and the associated conservation of energy, mass, and salt in CMIP6 and CMIP5 models. For most models, drift in globally integrated ocean mass and heat content represents a small but nonnegligible fraction of recent historical trends, while drift in atmospheric water vapor is negligible. Model drift tends to be much larger in time-integrated ocean heat and freshwater flux, net top-of-the-atmosphere radiation (netTOA) and moisture flux into the atmosphere (evaporation minus precipitation), indicating a substantial leakage of mass and energy in the simulated climate system. Most models are able to achieve approximate energy budget closure after drift is removed, but ocean mass budget closure eludes a number of models even after dedrifting and none achieve closure of the atmospheric moisture budget. The magnitude of the drift in the CMIP6 ensemble represents an improvement over CMIP5 in some cases (salinity and time-integrated netTOA) but is worse (time-integrated ocean freshwater and atmospheric moisture fluxes) or little changed (ocean heat content, ocean mass, and time- integrated ocean heat flux) for others, while closure of the ocean mass and energy budgets after drift removal has improved.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376
 
dik said:
Coincidence or not... it's happening. The CO2 traps heat, and by coincidence the earth's temperature is rising. As I mentioned, it's happening.

FWIW, I want to point out (if no one else has) that CO2 does NOT trap heat. That's a faulty understanding of global warming based on the poorly named
term "the greenhouse effect" that was spread in the media for so long. Greenhouses do exactly what you said, they trap the gases and heat. Not allowing the gases to expand and such so that it's forced to increase the temperature.

The CO2 warming effect is due to how CO2 will absorb SOME of the heat that is transmitted to it and radiate SOME of it out in all directions (back to earth and up into outer space).

I know I'm nit-picking you a bit dik.... But, I think that's an important distinction to make when you talk about global warming.
 
A recent paper on using the climate models to understand the variation in the AMOC, Atlantic Meridional Overturning Circulation, or Gulf Stream as we normally call it. IPCC says it will collapse this century with ensuing scary stories, observations say it is getting stronger.

But why do we see such a discrepancy between model and observational data? We consider three
possible reasons:
(i) The models are wrong.
(ii) The observations are wrong.
(iii) Models and observations are not expected to agree.


Having spent most of my life correlating models and observations I've heard all three of those many times. If it's 1 or 3 then there seems little point in making predictions from models.


Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376
 
We'll just have to wait... I understand that AMOC is diminishing and that it is possible to 'collapse'. What the results will be??? [ponder]

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik
 
Sorry guy, you're wrong... we just don't know where the data is taking us...

The data is showing us that the CO2 levels are as high as they've been for as long as man has been on earth. The data shows us the the CO2 buildup is a result of man's activities. The data shows us that the ocean's temperatures are increasing. The data show us that temperatures on earth are increasing. It's not conjecture... it's just not knowing where this will lead us.[pipe][pipe]

-----*****-----
So strange to see the singularity approaching while the entire planet is rapidly turning into a hellscape. -John Coates

-Dik
 
Don't forget the reason Ar is used to enhance He-Arc welding, it reduces in infrared heat loss; hence hotter welding..

CO2 does the same thing with global temps. Things get worse when artic permafrost melts, releasing large quantities of CH4 which reduces the IR loss from
the earths surface far more than CO2.

The IR effects even occur in process temperature measurements, though usually ignored.
 
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