In 1980, J. O’Keefe suggested that an Earth ring could have caused the onset and breakup of an Ice Age: material ejected from a lunar volcano could fall into Earth orbit and form a ring in its equatorial plane that would shade Earth’s winter hemisphere. Erosion of this ring would be followed by climate warmup. The theory did not catch on. Incidentally it was not in tune with its time, because an alternative account envisioned the Ice Age as the outcome of massive asteroid impact causing a one-time dust event. The latter line of reasoning had strong popular resonance as an image of nuclear winter. But if anything the prima facie case for seeking an Earth ring driven by lunar volcanism, in continuous if tenuous and wavering existence, has become stronger since 1980 as rings have now been found around Jupiter, Uranus and Neptune, around at least one planetary moon, and very recently in a new orientation in the plane of orbit of a Saturnian moon.
So let’s try to find an Earth ring if it is there.
Here as an introduction is a the poster paper I took to AGU/San Francisco in December 2010.
AGU 2010 Rings as of Dec 11. Errata – Note that the final figure’s title should read “Trends in 25-year record Tmax by day of year.” Further, I didn’t say so, but I moved all the Southern Hemisphere days-of-year forward by six months.