Maverick Philosopher

Crisis or hoax? How much of which? At the top of the Stack.

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Ed Buckner writes,

I can help with your first three questions.

1. Is global warming (GW) occurring?

2. If yes to (1), is it naturally irreversible, or is it likely to reverse itself on its own? And if irreversible, how would you know that?

3. If GW is occurring, and will not reverse itself on its own, to what extent is it anthropogenic, i.e., caused by human activity, and what are the human causes?

To the first, undeniably yes. The science is that as the carbon dioxide in the atmosphere has a physical effect that causes temperature to rise, all other things being equal. Note the rider: things are generally not equal, as there are other (well known) effects on climate. This also answers your third question. Yes, the warming caused by CO2 is man-made.

BV: You did not answer my third question. I asked to what extent is GW man-made. A priori, from the armchair, we know that if there is GW — if the Earth's atmosphere, land masses and oceans are in the aggregate getting warmer and warmer over time –  then GW cannot be wholly anthropogenic and also that human activity cannot have zero effect on it.  The empirical question for the climatologists is: how much of the GW is due to human activity?  The answer to this question has serious repercussions for policy decisions.  I suspect, though I do not claim to know, that the percentage of GW due to human activity — carbon emissions and what all else — is not high enough to justify the draconian "Green New Deal " measures of the GW alarmists.  The onus probandi, I should think, is on them to prove otherwise.

Is the science settled with respect to the empirical question I have posed? Has consensus been reached among competent climatologists?  That is not a rhetorical question. I would really like to know,

You write, "Yes, the warming caused by CO2 is man-made."  I didn't ask that question. I didn't ask what causes the warming. I asked, given that GW is occurring, about the extent to which the causes — whatever they are — are man-made. Not that I deny that CO2 plays a role.  But as you know, CO2 is also produced naturally, and some of the warming produced by naturally occurrent CO2 is precisely not man-made.  

So here is another empirical question: How much of the CO2 in the atmosphere originates naturally and how much from human activity? Has scientific consensus been reached on this question?

However, there is other stuff you must know. First, the known physics does not explain the predicted rises in temperature. The predicted rises are based on speculation to do with water vapour ‘positive feedback’.

Second, ‘global warming’ is ambiguous between cause and effect. We know a bit about the forcing, less about the water vapour possible cause. Regarding effect, we only have temperature measurement to go by, and the records are not long term enough. I have looked at Antarctic data and there is no evidence of any change, except at the limb of the Antarctic peninsula, which is coastal and affected by the sea. Also, the peninsula is some way from the Pole, and is naturally quite warm.

BV: Very interesting. So you are saying that the water vapor caused by GW causes more GW?

Third, and this addresses your question about reversibility: for every amount of CO2 in the atmosphere there corresponds an equilibrium temperature. Were all CO2 emission to halt, the atmosphere would take a while to establish that equilibrium, then remain there, so long as the CO2 concentration remained constant (which it won’t, as it will tend to fall).

Fourth, and global warmists tend to avoid this fact like the plague, the rise in temperature is logarithmic to the CO2 concentration. If the concentration doubles, equilibrium temperature goes up x degrees. If it doubles again, another x degrees. And so on. So a lot of the scare stories show linear charts of concentration, not logarithmic, which is somewhat misleading.

Fifth, and here I agree somewhat with the warmists, while the effect of warming can be continuous with no step changes, there is a well-known step change that occurs when ice melts. With an average of 1/10 degree below freezing point, the ice will not tend to melt. With the same amount above, it will eventually melt. So Antarctica would melt if its average temperature were a tiny amount above freezing point. But that won’t happen because Antarctica is huge and most of it close enough to the Pole that temperatures are way way below freezing.

Hope that helps.

BV: It does indeed, and thanks very much. The fourth and fifth points add to my understanding of the topic. The fifth is particularly interesting since it raises the logico-philosophical question of the metabasis eis allo genos, the shift into another genus, the somersault from a quantitative change into a qualitative one.

By the way Ed, since you are an historian of logic, do you have a list of sources on the metabasis eis allo genos?  I first encountered a reference to it in Kierkegaard. Does Trendelenburg say anything about it? Must go back to Aristotle. Medievals had to have addressed it.

One more question: if the issue is global warming, why the talk of climate change? That move involves an ascent from the species to the genus.  Obviously the global climate can change by getting hotter and by getting cooler.

Can you answer me this one, Ed?  (Knowing me, you know that I suspect wokeassed chicanery at work.)

COMBOX now open.