Glacial Cycles and Interplanetary Dust
Spectral analysis of proxy global ice data shows conclusively that the cycles of glaciation are astronomically driven. However the same analysis shows serious, perhaps fatal, difficulties with the standard (Milankovitch) theory. We argue that only the 41 kyr cycle of glaciation can be driven by insolation, and that the 100 kyr cycle, dominant for the past million years, is driven by orbital inclination. The linking mechanism is uncertain, although the most likely candidate is that variations in accreting interplanetary dust modulate the cloud cover, and this in turn drives the major glacial cycles.
KeywordsMethane Dust Ozone Helium Geochemistry
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