How accurate are climate models?

It turns it they’re almost universally spot on.

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Um … no they’re not. Potholer (your expert) isn’t without his critics.

Or another article specifically addressing/debunking your assertion,

http://joannenova.com.au/2012/10/man-made-global-warming-disproved/

Part of the issue in forecasting climate trends into the future is how much weight the models give to the climate sensitivity to increasing CO2 in the atmosphere. Estimates of CO2’s contribution to the greenhouse effect vary greatly between 2% (0.7 C) to as much as 26% (8.6C) of the total 33 C greenhouse effect. This means that there is some uncertainty as to CO2’s actual contribution. In addition, there is also uncertainty about the sensitivity of the climate to CO2. The best estimates I can find is that doubling CO2 in the atmosphere should result in a warming of 0.4 C to 1.2C before factoring in any feedbacks. See http://oceanweatherservices.com/blog/2019/01/29/what-is-the-greenhouse-effect/

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He’s a critic, yes, but incorrect in all his points.

No doubt you have access to Heller’s responses to all of Potholer’s responses (consistently debunking them) and we could continue our unproductive battle of the experts. You do, don’t you? Have you let yourself see them?

Suffice to say you won’t convince me and I won’t convince you. Believe what you want. I just say (with evidence) you’re wrong.

I have yet to see Heller be able to debunk his way out of a wet paper bag

If you could product that evidence you’d be famous.

“-ologist” can be wrong and keep a job, that includes lack of accuracy.

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It’s a percentage thing.

A paper or model produced using the scientific method and peer reviewed is far and away more likely to be correct then one produced using the flat-earth method. That is to search the internet for items that confirm per-existing beliefs.

That’s why I don’t use the Farmer’s Almanac for weather information.

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Here’s the summary from the linked article Peer review: a flawed process at the heart of science and journals - PMC titled " Peer review: a flawed process at the heart of science and journals".

“So peer review is a flawed process, full of easily identified defects with little evidence that it works. Nevertheless, it is likely to remain central to science and journals because there is no obvious alternative, and scientists and editors have a continuing belief in peer review. How odd that science should be rooted in belief.”

So you may trust peer review to deliver science, but scientists are human and subject to human failings which we ignore at our peril in any attempt to turn them into infallible gods.

Model simulations suggest a wide range of estimates regarding climate sensitivity (how the doubling the CO2 levels could eventually warm planet). Estimates range from a low of 0.8 C to as much as 4.5 C with the most likely range being between 1.2 C and 1.6 C. The difficulty in estimating future temperature based on CO2 levels is that there are many other factors that come into play, including atmospheric dust from volcanic eruptions, amount of forests and other vegetation, variations in incoming sunlight, aerosol particle pollution and the relationship of the deep global ocean currents.

I think what is not understood by most is exactly what @Fredwx explained pretty well above.
ALL climate models depend upon assumptions.
The model may be very good, but the assumptions if off the mark, make the results worthless.

For me, as an ex-meteorologist and someone who had looked at climate for 40+ years, it’s obvious that the planet has been warming or 15,000 years, OTHERWISE, we would still be in an Ice Age.
And since this warming started before humans had any impact, it’s not clear to me, what we can do about it.

Yes, human activity in the last 8,000 years (since the start of agriculture) has impacted the planet and has increased the warming. But that is probably a good thing, otherwise the data also shows without that extra human caused warming, we probably would have re-entered an Ice Age 10k to 8k years ago.

So in my mind, the real debate is how should we mitigate the warming, not think how we can stop it.
The planet has been warming and cooling for 4B years. It’s beyond hubris when humans think we can change that.

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The tactic you are using here is shifting the discussion from climate science to epistemology. Here is a article: What We Know, Can Know, and Don’t Know About Climate Change

We assume science works, well, because it works. Planes don’t fall out of the sky because we lack the ability to provide a satisfying epistemological backing for the theory of lift. So far, the lack of epistemologically satisfying answers hasn’t done much harm.

I thought I was agreeing with you, so it’s unclear to me, what you are trying to say.
Please clarify what your object to in my post.

Richard

I have three really simple questions…

  1. If the earth were the size of a basketball, how thick would the breathable atmosphere be?

  2. How many pounds of carbon are released by burning a gallon of gas/diesel?

  3. How many tons of carbon are released globally by burning Fossil Fuels?

What’s your point?
How many tons of CO2 are released by cooking using charcoal? (If you don’t know it, that’s how 2/3 of the world cooks).

How much CO2 is realized in the average volcanic eruption? How often are those eruptions?

No problem with whatever you believe. Stop driving, stop eating, stop consuming and that will solve the CO2 issue, but the earth will continue to warm.

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Three very simple questions.

Are you unable to answer them?

There is simply no point since you know all the answers.

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Here is a good, well written explanation of the issues. It’s uses risk rather than a simple yes/no approach.

Climate Science and Climate Risk: A Primer - by Kerry A. Emanuel.

Emanuel is Professor of Atmospheric Science at Massachusetts Institute of Technology and the author of the paper that was the subject of this thread Hurricane Carnot Engine. about this paper. -A Theory of Hurricanes

From the primer:

Considerably more than 90% percent of climate scientists attribute the bulk of the increase in global mean temperature over the past three to four decades to the anthropogenic increase in atmospheric greenhouse gases that commenced with the Industrial Revolution.1 The great majority of these scientists hold that continued warming presents significant risks to humankind over the coming centuries. What scientific evidence led the scientific community to these conclusions? How robust is that evidence? To what extent should we trust uncertain projections of future climate change based on complicated global climate models? How do we deal with climate change as a problem of risk assessment and management?

FWIW Enanuel is a political conservative and a Republican.