What else? Long term cyclical climatic fluctuation, driven by Sun-Earth interaction.

My own thinking is that ozone production is driven by this interaction, and that the ozone works as valve for total energy flow, something analogous to a transistor. But the exact mechanism of cyclical Sun-Earth variability is yet to be detemined.

By the way, to my knowledge the Finnish researcher Timo Niroma was the first to note that our Sun's variability appears to be tied to the gravtitional effects of Jupiter.

As a second by the way, I think that Rush Limbaugh was way out of line is belittling concern over ozone depletion due to freon.

In depth abstracts on all of the competing theories may be found in the Cambridge Conference archive.

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