Another piece of significant evidence regarding the earth's climatic history that can now be completely misunderstood or (more likely) misrepresented by the global warming deniers.
We've known for quite some time that changes in the eccentricity of the earth's orbit have played a role in the earth's climatic history. Actually, orbital eccentricity has been considered to be part of the puzzle, along with changes in axial tilt and the precession of the axis have all been lumped together to explain what are commonly called Milankovitch cycles (after the Serbian who first postulated the climatic connection). Definitely not my field, but if I interpret this correctly, Dr. Lisiecki is suggesting that the roughly 100,000 year cycle of glaciation that the earth has experienced over the last million years or so is largely explained by changes in orbital eccentricity.
That's great. The problem will come when some Exxon lackey touts this as evidence that climate change is not anthropogenically induced. Over geologic time, have there been climatic changes that man had nothing to do with? Of course. Is the current warming trend the result of human activity? Absolutely.
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