Change point method for detecting regime shifts in paleoclimatic time series: Application to delta(18)O time series of the Plio-Pleistocene

Although different paleoenvironmental time series resolve past climatic change at different time scales, nearly all share one characteristic: they are nonstationary over the length of the record sampled. We describe a recursive dynamic programming change point algorithm that is well suited to identify shifts in the Earth system's variability, as it represents a nonstationary time series as a series of regimes, each of which is homogeneous. The algorithm fits the data by minimizing squared errors not only over the parameters of the models for each subsequence but also over an arbitrary number of boundary points without restrictions on the lengths of regimes. The versatility of the algorithm is illustrated by an application to 5 Ma of Plio-Pleisotcene delta(18)O variations. We seek to identify either the single dominant "Milankovitch" frequency or linear combinations of frequencies and consistently identify changes similar to 780 ka and similar to 2.7 Ma, among others, in each analysis done. Our applications also provide support to the recent hypothesis that obliquity-based Milankovitch terms can account for the circa 100 ka cycle that empirically dominates the most recent 1 million years.

Title	Change point method for detecting regime shifts in paleoclimatic time series: Application to delta(18)O time series of the Plio-Pleistocene
Creator	Lawrence, C. E.
	Herbert, T.
	Lawrence, Kira T.
	Ruggieri, E.
Publisher	Paleoceanography
Academic Department	Geology & Environmental Geosciences
Division	Natural Sciences
Organization	Lafayette College
Date Issued	2009
Date Available	2011-12-01T18:44:02Z
Type	Article
Language	English
Bibliographic Citation	Ruggieri, E., et al. (2009) "Change point method for detecting regime shifts in paleoclimatic time series: Application to delta(18)O time series of the Plio-Pleistocene." Paleoceanography 24: PA1204.
Standard Identifier	Handle 10385/861
Standard Identifier	DOI doi:10.1029/2007PA001568
Permalink	http://hdl.handle.net/10385/861
Rights Statement	In Copyright
Rights Holders	American Geophysical Union