The lags in degrees from the del 18 O stack are shown on the left. Vertical arrangement is according to phase difference relative to del 18 O stack. Superimposed, phase-aligned records show high coherence with orbital forcing. Statistical summary of cross spectra of climatic time series. Signs have been changed for consistency with Figure PH-3.
Positive phase means that the variable lags the reference variable.
Phases of orbital, radiation, and climatic cycles. 18 O, others lag. In most cases, the behavior is the same for all three frequency bands At all three Milankovitch frequencies, certain sets of proxies tend to group together. This zero point occurs after a number of important environmental changes, suggesting that minimum eccentricity or some intermediate point in the cycle may be more significant. Thus, for the precession peak at 23ky, a lag of 40 degrees converts to 2,560 years.