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Comment Re:How is CO2 leading cause of warming? (Score 1) 143

So, answer it. If you model something and then compare your model results to actual reality and they're wildly divergent from that reality, what do you conclude?

Climate models are not expected to reproduce short term noisy variation. Therefore you can't conclude anything from comparing short term model outputs with short term measurements.

Going back to the dice analogy, the model is: given N rolls, you expect N/6 sixes. The fact this this does not give accurate results for small N does not allow us to conclude anything.

Comment Re:Bullshit! (Score 1) 236

I will believe these pig fuckers when they can accurately predict what will happen next year. Otherwise, why would I believe what they say will happen 10 years from now. Computer models are only as accurate as the assumptions programmed into them.

And this got voted insightful?!

Let me give you an analogy. I am going to write a simple computer model that predicts how many sixes you'll get if you roll a die 1000 times. In fact, here's the source code (Python 2 compatible):

print 1000.0/6

By your argument, this is wrong because it can't tell me whether the next roll of the die will be a six.

Comment Re: Yawn (Score 1) 367

RockDoctor: I think you are misunderstanding my comment. What I was saying was that I *don't* believe the CO2 effect is saturated and am sceptical about those who claim that it is. This is not because I have expert knowledge but because I don't believe in conspiracies. Apologies for not being clear.

Comment Re: Yawn (Score 1) 367

If it were so trivially obvious that the CO2 effect is saturated, it follows that lots of scientists are either too stupid to understand this or they understand it but are deliberately ignoring it or 'covering it up'. Alternatively, maybe there actually is a bit more to it than there seems. As a sceptic, my instinct is to favour the latter.

This article explains it quite nicely and even goes into the history of why some of the 'obvious' conclusions turned out to be faulty.


Comment Re: Yawn (Score 1) 367

>An example of how the alarmists seize on every theoretical positive feedback for their models and ignore negative feedbacks which the observable long term stability of the climate demonstrates must exist, otherwise the first really big volcano eruptions would have charbroiled the planet.

You are assuming that a net positive feedback implies instability rather being something that might drive the system to a new equilibrium. There is plenty of historic evidence of positive feedback - insolation changes alone are not sufficient to account for past changes in climate - and the climate has been stable long term only in the sense that it has not got into a runaway feedback. Its 'stability' has encompassed a very broad range of conditions, many of which would be very uncomfortable for human civilisation as we know it.

I don't think you are correct that negative feedbacks are ignored. There is plenty of discussion in the literature of which way cloud feedbacks go and it is widely acknowledged to be a complex area. Nevertheless, I am not aware of any compelling evidence of strong negative feedback from clouds.

Let's turn things around. We know that there *are* feedbacks - they are irrefutable from basic physical arguments. Are you saying that it just happens that these all balance each other out?

Comment Re: Yawn (Score 1) 367

> Indeed.

? So you agree that your assertion was innumerate.

Anyway, I see you've moved on to some different zombie arguments.

> And the biggest of those is water vapor, by an overwhelming margin.

It's not an 'overwhelming' margin. Yes it is a stronger GH gas than CO2 but it is limited by its saturation vapour pressure in the atmosphere, which in turn is a function of temperature. Hence, as you know, water vapour can amplify the GH effect of CO2.

> Some even question whether there's *any* IR left over in the proper bands for C02 to make a difference.

Who questions this and are they credible?

Comment Re: Yawn (Score 1) 367

> Mind you, some intuitively ridiculous things are in fact true.

Perhaps you should have taken more heed of this possibility before embarrassing yourself.

If you had engaged your brain you might have realised that your assertion about percentages makes sense only if the entire atmosphere comprises greenhouse gases rather than mainly consisting of gases that are unaffected by IR. It is the change in greenhouse gases that is important.

Comment Re:... and yet no global warming in the last 16 ye (Score 1) 367

Here's one good reason for discounting anything associated with Roy Spencer: Look up "An Evangelical Declaration on Global Warming" and note who signed it. He's welcome to believe what he likes but he's no scientist. As for the chart itself, that appears to be from the uncorrected version of Loehle's paper, which in any case was published in the Mickey Mouse journal Energy & Environment. What other information do you have that backs up why to trust this single chart rather than other temperature reconstructions?

Comment Re:Final nail? (Score 1) 398

I don't know. Do you think there is? For sure, it doesn't lend any support to the claim that an AC made up there that things have 'levelled off'. Unless of course they meant that little bit at the right. If they did, then they must be pretty thick as they have not noticed that similar features appear at various points earlier in the graph but that there is nevertheless a clear upward trend. Certainly there does not appear to be sufficient information to draw any conclusion whatsoever from that little bit at the right.

Comment Re:Final nail? (Score 3, Insightful) 398

There is some information on this site that gives an overview of the adjustments that have been made to the USHCN data and provides links to further detailed references. I am no expert but my impression is that the adjustments have been made for sound and fairly standard reasons such as time of observation. Furthermore, and the whole point of that page, a different method of adjustment has been applied that yields very similar results. This would tend to suggest that both methods are robust.

It is a standard 'skeptic' tactic to complain vaguely about 'adjustments' to data as if adjustments are intrinsically wrong or suspicious whereas in fact it is rare in science for raw data not to need some pre-processing before robust conclusions may be drawn from it. However I will give you the benefit of the doubt. Unlike me, you might very well be an expert on this topic, so I'd be interested if you could explain specifically what you think is wrong with the adjustments.

Comment Re:And yet ... (Score 1) 468

And where exactly is this being 'vilified'?

Slashdot (the headline of this post, for one) felt the need to counter Bloomberg's summary with NY Times summary.

I see. The problem is that you don't know what vilified means. Fair enough.

All I see is a study that accepts mainstream climate science and offers another data point about climate sensitivity

You must be talking about something else then. The study claims the data shows plateauing since the 2000. It doesn't directly conclude that the previous conclusions (that GW is anthropogenic) were wrong. But it does provide evidence to support investing such a possibility.

You seem to be a bit confused. The whole point of the study is to estimate climate sensitivity - how much the atmosphere warms for a doubling of CO2. How on earth does that provide evidence against AGW?

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