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Translation: I can't cite any data because I don't have any data.

Translation: you have conceded all the other points and are now grasping at straws and straw men.

Since you seem to be unable to use Google, here is the first hit on Google:

https://arstechnica.com/scienc...

Developed vs third world:

http://www.energytrendsinsider...

20th century patterns aren't "current trends". Current trends suggest constant or declining carbon emissions.

The data shows otherwise: http://www.energytrendsinsider.com/wp-content/uploads/2012/07/Global-CO2.png

Your graph cuts off in 2010.

I notice you don't bother to cite any data supporting your claim of a trend of "constant or declining carbon emissions". Unless you have some data showing such a trend-- and a trend long enough to be meaningful-- I stand by my statement.

If you're quibbiling, Manabe and Wetherald's calculated climate sensitivity was 2.4, not 2.0. [...] (with your rounding of "2.4" down to "2" corrected)

I didn't round, that's what the paper says: "According to our estimate, a doubling of the CO2 content in the atmosphere has the effect of raising the temperature of the atmosphere (whose relative humidity is fixed) by about 2C". You really need to read the paper, instead of random blog posts.

I'd actually checked the number out of a textbook that I happen to have near my desk (Liou, An Introduction to Atmospheric Radiation, 1980, if it matters-- my usual go-to book on atmospheric light scattering) instead of digging up the original paper. But turns out it's not hard to dig up the paper, it is on the web several places, so it's easy enough to check: http://ruby.fgcu.edu/courses/twimberley/EnviroPhilo/ThermalEqu.pdf

And, how about that?-- you're almost right. "About 2C" is indeed what is says... in the abstract.

In the body of the paper, though, they give the calculated result to more than one figure. Table 4 and table 5 shows their calculated results. The increase from 300 to 600 gives an effect of 2.36C (for fixed relative humidity and "average cloudiness;" slightly higher for clear skies).

So, I withdraw my statement that you rounded their result down. In fact, it wasn't you: they did the rounding. Nevertheless: the number was 2.36 (but the parts after the decimal point are probably not significant.)

For what it's worth, their 1975 paper, calculating with a three-dimensional model instead of the 1967 2D model (which means that they have both oceans and continents, instead of an average of ocean and continent), came up with 2.39 degrees per doubling-- nearly the same.

I don't see much real information in the rest of your post, you're arguing your opinion and policy, and not significantly disputing facts. You're saying you don't like the models because you don't understand the feedbacks, but you're more or less ok with the results to the first significant figure, although to a second significant figure you prefer a number slightly on the lower side but still within the error bars, but you think that existing societal trends will reduce CO2 emissions anyway so the predicted warming will be lower than the highest value of the IPCC scenarios (which is what the IPCC also seems to thing: that is the high case.)

OK. I'm not sure that there's enough in that to bother arguing with.

I will, however, quibble with two points:

There is nothing "paradoxical" about it; irrational climate change deniers are largely a figment of your imagination.

No, irrational climate change deniers are certainly out there, and say all sorts of bizarre things. However, you have clearly shown that you are not an "irrational climate change denier," since you're arguing with numbers based on the real science. That is neither irrational, nor even being a "climate change denier" of any kind. There doesn't seem to be a quick category nam

The question "what happens if current trends continue" seems like a reasonable thing to ask

20th century patterns aren't "current trends". Current trends suggest constant or declining carbon emissions.

The data shows otherwise: http://www.energytrendsinsider...

But that's irrelevant: the question what if current trends continue is still an interesting one to ask, even if the answer is "current trends won't continue."

But, by the way, why should "current trends continue" be "economically utterly implausible"? It's not economically implausible now, why does it suddenly switch to being implausible?

Because the price of fossil fuels goes up as they are exhausted

Historical data shows that fossil fuels don't get exhausted, because new supplies are found.

and the price of carbon neutral sources are steadily falling. Not taking that into account is absurd.

And that's why they also looked at the effect of substitution of other sources.

Basically, you took a whole array of different scenarios put forth by IPCC to look at the effect of all sorts of different possible things that could happen, you took the most extreme one, and you say "look at their prediction! It is absurd!". That wasn't their "prediction". That was their analysis "here is the result if this one particular scenario takes place."

I gave this as an example of their use of economic predictions; they use economic predictions in all their analyses, as well as predictions about the effects of government policies. Their other scenarios suffer from analogous problems, it's just not worth going through every one of them to get my main point across, namely that their conclusions are not just rooted in "basic physics" but require lots of other assumptions that are far more speculative and not rooted in any science.

My objection stands. They gave a wide variety of different possible scenarios but you chose to point out only the most extreme what-if scenario and ignore the fact that this was only one of many different scenarios. If they hadn't looked at a "what if current trends continue" scenario, then that would have been dishonest.

As you pointed out very clearly in your previous post, the current IPCC best estimate of climate sensitivity, 3 plus or minus 1.5 degrees per doubling, is pretty much identical to the one-dimensional constant-humidity model of Manabe and Wetherald.

No, their most likely prediction of 3C is not the same as 2C, it's 50% larger.

If you're quibbiling, Manabe and Wetherald's calculated climate sensitivity was 2.4, not 2.0. That is 25%, not 50%. And within error bounds of the current best estimate. You do know about error bounds? This is how science works.

I'm annoyed at people attacking the science because they don't like proposed policies

Stop pretending that there is something like "the science". People attack some of the science in the report because some of the science is in fact weak. Scientific conclusions and arguments are only as strong as the weakest link, that's why many people consider the overall conclusion of the report to be weak even if they (like me) agree that parts of it are strong.

You've been asserting that some of the science is weak, but you haven't shown that-- you've just said it over and over again, on the assumption that repeating something enough times is as good as actual evidence.

Nevertheless, paradoxically, you seem to actually agree with the conclusions of the report, since (with your rounding of "2.4" down to "2" corrected), you quote a climate sensitivity within the error bars of the current best estimate.

All 16% of it.

How about almost every climatology study done in the last forty years?

I tell you what. If you don't think AGW is real, why don't you explain where all the energy being absorbed by CO2 in the atmosphere is going. Are you advocating the "magic heat sink back into space" theory?

I think AGW is real, but I fail to see how you get from that to August 8 as a single date of an "overshoot day". Does this imply that, since on August 8 we're about 60% through the year, we'd have to reduce our CO2 output by 40% to completely stop the increase of atmospheric CO2 levels? That doesn't make any sense at all, given that the worldwide CO2 emissions were 40% lower than today roughly 30 years ago, but by that time the CO2 levels had been increasing for more than a century already. So that doesn't make sense at all unless you postulate that the natural CO2 sinks work at a much higher pace at today's CO2 levels compared to those in 1986.

So what does August 8 represent? Are they computing one overshoot day per type of resource (Hydrocarbons, aluminium, copper, ...) and take the average? Or the minimum? And what's a "copper overshoot day" anyways, given that we don't "use up" metals the way we do oil or gas when we burn it. If you count metal as "used up" if it's not recycled but replaced with new raw materials, then the corresponding "overshoot day" would be January 1st because the Earth's crust contains a fixed amount of extractable ores.

You are confusing "oil" and "gasoline"

You're kidding right?

so you can declare a "win" in your mind

If you think I care that much about the "win" you've completely misunderstood me.

with an argument nobody is having with you.

*shrug*, I re-read your post I initially replied to and parsed it more carefully; in fairness you didn't directly link supply and demand to price.

Not sure actual numbers confirm your theory.

http://www.energytrendsinsider...

Frankly if most of your driving is highway I don't see the point, my $17,000 non-hybrid Honda Civic is competitive with the Prius when it comes to highway driving.... I can milk 43-44mpg out of my Civic without trying that hard, and that's despite living in a hilly region.

I think that's an important point. The hybrids aren't peaking because people aren't interested in fuel efficient vehicles. They're peaking because there's so many fuel efficient vehicles available.

"Peak Oil is the point in time when the maximum rate of petroleum extraction is reached" - http://en.wikipedia.org/wiki/P...

It looks like the GP does know what peak oil is. the following chart shows that the oil production has been decelerating for the last 50 years and growth seems to have stopped in about 2005: http://www.energytrendsinsider...

All the while demand is increasing exponentially.

It is really all about coal. USA Has been converting to Natural Gas, China has been gorging on coal. Finding a way for China to get off coal is really important. http://www.energytrendsinsider...