Jack,

“If the CO2 hypothesis is correct, at no time should the temperature trends be anything but up.”

Not at all. That an increase in the concentration of CO2 produces a background of warming does not preclude other natural and unnatural effects from causing cooling that can temporarily (a decade or more) be even greater. Climate models include both anthropogenic and natural effects, and show temperature drops in the time series.

Listen to yourself:

does not preclude other natural and unnatural effects from causing cooling that can temporarily (a decade or more) be even greater.

Yes, natural and unnatural effects can override CO2 for decades. Which is why there is no point in controlling CO2 emissions. There are other forces at work, rendering mankind’s effort trivial.

No, Tom, you are wrong.

You are either ignorant, or you are deliberately misrepresenting the facts.

For your sake, I will assume it’s the former, and enlighten you:

Arrhenius (1906) estimated 1.6 C° of warming at CO2 doubling, down from 5° C in his paper of 1896; however, Al Gore, Sir David King and others cite only the 1896 paper. [source, "Red Flag #21"]

Despite your link [which was clearly written to obtain grant money -- just read the summary, and look at the alarming graphs based on rank speculation], there are no “observations” for climate sensitivity. Climate sensitivity has not been observed, because it is so small. Climate sensitivity is simply a model output, and the warmist contingent is still desperately, and impotently, hoping for temperatures to rise in order to prove its existence.

The estimates and models of climate sensitivity vary all over the map. And there is no consensus for any particular climate sensitivity number. As your summary link states, there is wide uncertainty, ranging from 1.5° C to 6° C and more. But empirical, real world climate sensitivity appears to be not much above zero.

Now that your “alarming” argument has been corrected, this is a good opportunity for an ad-hoc ethics test:

By admitting your post was factually wrong, and that you are left only with facts that support natural climate variability, will you now become a skeptic of the CO2=AGW hypothesis, which depends entirely on a large climate sensitivity number?

Or will you just move the goal posts, as usual?

I predict the latter. Prove me wrong. Please.

You’re out of date, about a century. Check out what his calculations were after he used Navier-Stokes equations after the turn of the century. You’ve been propagandized, honey.
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REPLY: Kim and Tom please give it a rest. – Anthony

Just two quick responses:

“Arrhenius’s own calculations show a small effect from CO2″

You’re wrong: he calculated an alarming 5 to 6K doubling temperature.
Arrhenius, Svante (1896). “On the Influence of Carbonic Acid in the Air Upon the Temperature of the Ground.” Philosophical Magazine 41: 237-76.

Various observations favour a climate sensitivity value of about 3 K, with a likely range of about 2 – 4.5 K:
http://www.iac.ethz.ch/people/knuttir/papers/knutti08natgeo.pdf

Naw, the quantification is only there during the last quarter of the last century. Not before, and not since. Once again, you misconstrue my point.

You are right, climate sensitivity to CO2 is the key point. You’ve not supported your belief in its high sensitivity with either quantitative arguments or with underlying scientific theory. And every day the earth cools further diminishes your hypothetical high sensitivity. When empiric facts dispute predictions from hypotheses the scientific method requires re-evaluation of the assumptions underlying your hypotheses. Get busy.
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Climate sensitivity is obviously a key aspect of the science of global warming. Kim doesn’t want to further discuss it in any quantitative way, and as there’s apparently no appetite from anyone else I agree it’s time to move on.

If the deceit leads to expensive and dangerous policy, those being deceitful will be exposed and held responsible. Carbon encumbering is likely to become deadly. Think about it.
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REPLY: Tom P is exceptionally stubborn, and this thread has gone so far OT now that it is mostly all about this argument. I’m getting a bit weary of Tom P. hijacking threads. Perhaps it is just best to ignore him. – Anthony

You are hopeless. Your misunderstanding of my point does not make it a circular argument. If there were a perfect correlation of CO2 and temperature then that would be evidence that there is an important CO2 effect on climate. I am making exactly the opposite point, that since we can’t see a correlation, then it is likely that CO2 has a negligible effect on climate.

And Arrhenius’s own calculations show a small effect from CO2. It is the mistaken addition of a large positive feedback of water vapor that has misled you and the models.

And I’ll counter with this challenge. Show that the effect on temperature that the models and the IPCC have promoted has been scientifically demonstrated. You can’t; it hasn’t been done.
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