09-10-2018, 06:59 PM
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#2811 (permalink)
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Not Doug
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RedPoint, do you know if any of these models have been used to predict the past and if so, how they did?
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Today
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Other popular topics in this forum...
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09-10-2018, 07:04 PM
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#2812 (permalink)
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Human Environmentalist
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No idea; I'm no subject matter expert. It just seems to me that the way you test any model is to compare it against known results. If you had a fluid dynamics algorithm for aerodynamics, you would test the predicted results with real world models. Same reasoning applies with climate change modeling.
I'd be way more convinced by a model if it accurately predicted past climate conditions, and that's something I haven't seen demonstrated before.
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09-10-2018, 07:42 PM
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#2813 (permalink)
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EcoModding Lurcher
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First hit in Google for
"how are climate models tested?"
Quote:
So all models are first tested in a process called Hindcasting. The models used to predict future global warming can accurately map past climate changes...
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09-10-2018, 09:34 PM
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#2814 (permalink)
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Not Doug
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It seems that most people either accept Andygriffith Global Warming or they refuse to consider it. This seems to be the only [mostly] civilized discussion that I have seen.
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09-10-2018, 09:36 PM
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#2815 (permalink)
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Human Environmentalist
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Granted, I haven't looked yet, but I still haven't seen someone show the public how a given model has accurately hindcasted past climate, and to what degree of accuracy.
You'd think that is the first thing the public should see if trying to convince them of the future. While that link said models are hindcasted, they didn't show the hind-casting and accuracy.
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09-11-2018, 01:26 AM
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#2816 (permalink)
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Master EcoModder
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If you dig, you can find numerous papers showing this process of testing.
But it would help public discourse if it was talked about more often.
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09-11-2018, 02:36 AM
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#2817 (permalink)
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Not Doug
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Quote:
Originally Posted by sendler
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Did anyone watch this?
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09-11-2018, 08:30 AM
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#2818 (permalink)
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Corporate imperialist
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The church of man made global warming says "trust us our computer modeling is flawless" and here we are nearly 25 years later and every computer model I am aware of has failed.
They all said it was supposed to get warmer and warmer and that the rate of warming was supposed to increase, the ice was supposed to melt faster and faster, there would be less an less ice.
No one said anything about the ice loss slowing, reversing, this is supposed to be the death spiral and they should be saying "I told you so".
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09-11-2018, 11:49 AM
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#2819 (permalink)
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The road not so traveled
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I have only seen the data on a couple of models used to reproduce previous temperatures, they were so-so.
On a computer that is unfortunately dead now I had built a rather basic model that went back 1000 years. I used the past data to fine tune the model as much as I could so the hind cast was actually fairly accurate. I didn't future cast because whenever I added CO2 to it things blew up in the modern day so I left it out and figured the discrepancy would likely be due to us. It showed approximately half of the observed warming was natural, and followed with the pause that used to be in the data-sets which was due to the long low portion of the solar cycle.
Mind you this was before the data-set changes a couple of years ago. If I was to do it with the way the data-sets are now it would show that we should be cooling (changed the TSI data as well). Meaning that we are responsible for more of the warming than has been observed.
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09-11-2018, 12:15 PM
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#2820 (permalink)
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Human Environmentalist
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To be clear, the real problem with global warming is the speed at which it is happening. The climate has always changed and always will, but adaptation is made difficult when it happens geologically quickly; which is to say in a few hundred years rather than thousands or millions.
It's difficult to feel like addressing global warming is a solvable problem, and one which is a big enough deal to devote extreme resources to. Since the earth has been warming for thousands of years now, the scientists talk in terms of delaying temperature rise. An example might be the Paris Climate Agreement. If all the nations adhered to that agreement, we would delay the temperature rise by something like 6 months (or other geologically short time period). So basically, if we do nothing than we just get the projected temperature increase 6 months earlier.
Basically, if we stopped emitting any man-made CO2 immediately, we are still projected to increase temperature a couple degrees C within some short timeframe.
While climate change will need to be considered, the problem of our day is transitioning away from fossil fuels as a primary energy source (Sendler's concern). Climate change will be the problem of my great grandchildren. That and designer babies, coupled with underpopulation. The population explosion will turn into a population contraction within my lifetime.
I wish I could take a short position on Social Security.
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