Miklankovitch Theory - Hits and Misses
Milankovitch Theory has become an important tool in geologic practice andthought, and is sufficiently conspicuous to provide a rewarding target for criticism.The chief problem arising has to do with the prominence of a cycle near 100,000years, whose origin is not clear. Most practitioners, presumably, would accept aclose relationship of that cycle to precession of the equinoxes (that is, cyclicchanges in seasonality), along with dynamical properties of the system thatenhance the amplitude of the 100-kyr cycle at the expense of others. In anycase, Milankovitch Theory has proved useful, both for age assignments and forstimulating thought about relationships between climate change andsedimentation, as is readily evident from the relevant literature. It would bedifficult to replace. Neither does it seem desirable to do so: the chief problemnoted in regard of the theory (the 100-kyr problem) is not necessarily a part of thetheory, which is concerned with change rather than with condition. The 100-kyrcycle is linked to condition. The problem raised by critics seems to be the timescale of integration of change, a problem not addressed in Milankovitch Theory.A necessity for additional processes and mechanisms not considered inMilankovitch Theory cannot be excluded.