Abstract
This paper addresses several issues concerning Milankovitch Theory and
its relationship to paleoclimate data over the last 800,000 years. A
model is presented that deconvolutes the precession index (precession
modulated by the eccentricity) and the obliquity contributions to the
percentage change between successive mean-daily-insolation minima and
maxima. The sum of these contributions is in close agreement with the
corresponding benchmark calculation of J. Laskar et al. The model
predictions indicate that the precession index contribution dominates
such insolation changes, and its time-dependent behavior correlates with
the occurrence of interglacial and glacial periods and temperature
trends during these periods. Best fit curves to the separate
contributions appear as quasiperiodic waves that correlate with
interglacial initiations and terminations through their constructive and
destructive interference. However, a comparison of model predictions
with the EPICA Dome C (EDC) data indicates delayed inceptions for Marine
Isotope Stages 18d and 13c, which have also been noted by Parrenin et
al. through a comparison of LR04 benthic 18O and EDC
ice core datasets. Finally, the model enables the classification of
interglacial periods into two distinct types that approximately account
for their durations. This classification also enables a low-resolution
estimation of the Holocene termination based solely on celestial
mechanical forcing.