Changes In Solar Brightness Too Weak To Explain Global Warming

"Your initial comment was to the effect of how one molecule of CO₂ could influence 2500 molecules of air. You nicely demonstrated how in your response to me! I used the cotton sheet to demonstrate how a small number of "molecules" can significantly influence the bulk properties of a much larger quantity of molecules."

One could also argue that only a few molecules of cyanide will influence the billions of molecules in the human body. However, either comparison to GHGs is unfair since the mechanics and inherent efficiencies are drastically different.

In the blanket scenario, the blanket is trapping heat via a barrier to convection from a heat source totally enveloped by the blanket.

In contrast, GHGs do not impede convection, do not fully impede radiated heat, do not reflect or trap the majority of the heat back to within it's envelope and in the case of the earth, the main heat source is not within the envelope of the GHGs. A blanket is way more efficient than GHGs at trapping heat (technically this isn't a good correlation since a blanket will trap heated air, but traps little energy from infrared sources, but I'm trying to keep things simple here). GHGs induce heat from excitation by IR wavelengths... they do not trap heated air like a blanket does.

Since the mechanics and efficiencies are very different, the blanket analogy to the "1 vs. 2500 molecules" point is invalid.

"Because there are no other factors (such as solar variability) <that we are aware of and fully understand> that could cause such an observed increase, the level of "firmness" (definitive attribution) to increasing atmospheric CO₂ as the main cause of the observed warming trend is becoming stronger."

There. I made your comment logically correct. To state it otherwise implies that we do know it all... and we don't.

"Provide examples of this observation."

I had this one lying around for awhile.....

Discounting the CO² data prior to 1958 (which I hold in dispute for reasons outside the original scope of my comment), numerous periods indicate no close causal effect of CO² levels on temperature anomalies.

Not including the effects of the volcanic events noted in the chart;

GTAs in the period between 1958 to the Agung event were in a decline followed by short level period.
GTAs in the period between 1970 to 1976 were also in a decline.
Dips in the GTAs also occurred after the effects of St. Helens, El Chichon and Pinatubo.
The overall GTA trend diverges from the CO² trend after 1978.

If earth's system is as sensitive as you infer, and if solar variance has been of no serious influence, then GTAs should track more closely with changes in CO².

Richard Axtell asked:

"Can the mechanism that has been hypothetically proposed, a convection cell or local condition where a local concentration of CO2 cause a much greater Greenhouse effect than would occur in the same region with .01 or .02% less CO2 and the same percentage of water vapor?"

cogitator responded:

"CO2 is a well-mixed gas, so the situation I think you are describing doesn't happen."

I would interject here that although CO² is well-mixed on a global basis, there must be higher concentrations near it's sources (cities, swamps, forests, etc..) before it is more evenly distributed. A drop of food coloring will evenly mix with a gallon of water, but only after enough time for circulation is provided. Until then, the heaviest area of saturation is nearest to the injection point.

If CO² is such a potent GHG as claimed, then this could in part explain the "heat island effect" near cities where CO², CO and various hydrocarbon compounds would be most prevalent. Has anyone performed any heat island studies in city/urban areas to measure the GHG levels vs. local temperatures on days when energy use is high (weekdays) compared to when energy use is low (weekends)? I'd be interested in this.

Perhaps you could enlighten me about the Lomnicky Peak Monthly Mean Coronal Index chart in the following paper: Scroll down to see Lomnicky chart.

I know the corona supposedly supplies only a small amount of the total energy or radiation from the sun, but I also am given to understand that the corona or holes in the corona have an effect on the earth's upper atmospheric temperature.

The Lomnicky Peak Monthly Mean Coronal Index seems to mimic the global temperature average in a way. It increases significantly about the time that global temperature supposedly deviates from the Friis-Christensen and Lassen correlation or other correlations. It increases far more than the 0.07% change in radiative energy talked about above.

If the corona, insignificant as it might appear to be, has a demonstrable effect on the upper atmosphere, might it also be having an effect on global temperature. Perhaps it affects cloud formation and thus affects reflected energy.

What I think our exchange, and of many others on this thread, has done is to make it clear that it is not clear that man-made CO2 emissions are without doubt the single and only cause of climate change. However, that is what we are being told.

I would say that it's becoming clearer that the current major driver of climate change is increasing atmospheric CO2 concentrations. Most the scientifically-literate skeptics are assuming a "the warming will be small and we can cope with the changes" position, given the growing body of evidence.

I think further research can establish real data that will bring new understanding of just what is going on.

That would be helpful.

BTW, it's CO₂, not CO². For the sake of speed, I'll just use CO2.

I don't think there's anyone that would assume a linear or simple cause-effect relationship between increasing atmospheric CO2 and temperature. The climate system is complex and non-linear. One of the discussion points is how much solar influence caused the early 20th century warming trend; the cool period from the peak in the 30s to the mid-1970s is attributed to natural variability plus a possible contribution from sulfur aerosols due to rapid post WWII industrialization. And there is also the short-term effect of the volcanoes, though between Katmai and Pinatubo there wasn't anything really big.

"BTW, it's CO₂, not CO². For the sake of speed, I'll just use CO2."

Noted. I need to proof-read a bit better. I was using the _wrong ^tags.

As for the rest of your comment, I don't see how any of that explains the divergence of trends past 1978. If that's due to the nebulous factor of natural variability (those many things which we don't yet understand), then it would seem that natural variability is a much more influential factor than CO_2.

I don't see how any of that explains the divergence of trends past 1978. If that's due to the nebulous factor of natural variability (those many things which we don't yet understand), then it would seem that natural variability is a much more influential factor than CO2.

You see a significant divergence of trends between GTA and the increase in CO2? GTA will vary year-to-year (clearly El Nino / La Nina is a significant factor). I see the expected greater variability in GTA, but they both seem headed in the same direction.

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