Time-series analysis of the Pleistocene deep-sea paleoclimatic record

Abstract

Pleistocene deep-sea cores V16-205, V28-239 and composite core RC11-120/E49-18 were selected for a time-series analysis of climatic periodicities which correspond to secular changes in the earth's orbital parameters. These data were analyzed using the Periodic Regression with Cyclic Descent — a technique which offers three major advantages over more conventional approaches because (1) the observation interval may be unequally spaced with respect to time, (2) resolution of all the discrete periodic components present in the data, including those with low frequencies, is made possible, and (3) the associated Monte Carlo experiments permit the evaluation of the importance of the observed periodic components vis-a-vis “red” climatic noise. Analytical results indicate periodicities which correspond to secular changes in the earth's orbital parameters. In particular, the results strongly suggest a quasi-periodicity of 413,000 years recorded in deep-sea globigerina oozes. Clearly this periodicity is reminiscent of a beat in the eccentricity of the earth's orbit, first detected in tropical North Atlantic core V16-205 by Briskin and Berggren (1975).