Does the global climate possess a stabilizing negative feedback and is the likely candidate for such a feedback cloud cover ?
The excellent whimsical but nonetheless academically highly authoritative, Canadian Spectator draws our attention to an overlooked paper in 2003 in the Geological Society of America Journal Vol13 Issue 7 July 2003.
Celestial driver of Phanerozoic climate?
by Nir J. Shaviv, Ján Veizer
They examine how the two principal drivers of the global climate ;
1 Atmospheric levels of CO2
2 The galactic cosmic ray flux (CRF)
are and have been linked to climate variability in the context of daily to millennial variations, ands also over geological time scales e.g the Phanerozoic (past 545 m.y.),
It would be pointless to abbreviate the detailed arguments, maths, geological record, hydrogeological and climate records they use to detremine and illustrate their thesis. There conclusion is however, that when considering both forcing effects that ;
We find that with none of the CO2 reconstructions can the doubling effect of CO2 on low-latitude sea temperatures be larger than ~ 1.9 °C, with the expected value being closer to 0.5 °C. These results differ somewhat from the predictions of the general circulation models (GCMs) (IPCC, 2001), which typically imply a CO2 doubling effect of ~ 1.5–5.5 °C global warming, but they are consistent with alternative lower estimates of 0.6–1.6 °C . See ...
Lindzen, R.S., 1997, Can increasing carbon dioxide cause climate change?Proceedings of the National Academy of Sciences, v. 948335–8342.).
They claim in their discussion of Potential implications that their approach , based on entirely independent studies from astrophysics and geosciences, yields a surprisingly consistent picture of climate evolution on geological time scales.
They state that the proposition that celestial phenomena are important for understanding the vagaries of the planetary climate is viable . Most intriguing (and of vast important to the current debate if correct) is their claim that one interpretation of their results could be that the global climate possesses a stabilizing negative feedback and a likely candidate for such a feedback is cloud cover (Lindzen, 1997 op cit Ou, H.-W., 2001, Possible bounds on the Earth's surface temperature: From the perspective of conceptual global mean model: Journal of Climate, v. 142976–2988.).
This therefore implies they argue that the water cycle is the thermostat of climate dynamics, acting both as a positive (water vapor) and negative (clouds) feedback, with the carbon cycle “piggybacking” on, and being modified by, the water cycle. See ...
Nemani, R., White, M., Thornton, P., Nishida, K., Reddy, S., Jenkins, J., Running, S., 2002, Recent trends in hydrologic balance have enhanced the terrestrial carbon sink in the United States: Geophysical Research Letters, v. 29106-1–106-4.
Lovett, R.A., 2002, Global warming: Rain might be leading carbon sink factor: Science, v. 2961787.
Lee, D., Veizer, J., 2003, Water and carbon cycles in the Mississippi river basin: potential implications for the northern hemisphere “residual terrestrial sink”: Global Biogeochemical Cyclesv. 17DOI: 10.1029/2002GB001984.
This is they say an aid to understanding the complexities of climate dynamics and ultimately to quantification of its response to potential anthropogenic impact.
Which of course flies in the face of the hysteria which supports the unwelcome, wholesale and erroneous belief that the sole driver of climate change AKA global warming is driven by atmospheric CO2 and that the source of that is anthropogenic.
Anyone seriously interested in educating themselves about the debate would benefit from reading this major but evidently overlooked study....at least look at the graphs which are very convincing.
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