Optimizing significance testing of astronomical forcing in cyclostratigraphy

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doi: 10.1002/2016PA002963
Author(s): Kemp, David B.
Author Affiliation(s): Primary:
University of Aberdeen, School of Geosciences, Aberdeen, United Kingdom
Volume Title: Paleoceanography
Source: Paleoceanography, 31(12), p.1516-1531. Publisher: American Geophysical Union, Washington, DC, United States. ISSN: 0883-8305 CODEN: POCGEP
Note: In English. 45 refs.; illus.
Summary: The recognition of astronomically forced (Milankovitch) climate cycles in geological archives marked a major advance in Earth science, revealing a heartbeat within the climate system of general importance and key utility. Power spectral analysis is the primary tool used to facilitate identification of astronomical cycles in stratigraphic data, but commonly employed methods for testing the statistical significance of relatively high narrow-band variance of potential astronomical origin in spectra have been criticized for inadequately balancing the respective probabilities of type I (false positive) and type II (false negative) errors. This has led to suggestions that the importance of astronomical forcing in Earth history is overstated. It can be readily demonstrated, however, that the imperfect nature of the stratigraphic record and the quasiperiodicity of astronomical cycles sets an upper limit on the attainable significance of astronomical signals. Optimized significance testing is that which minimizes the combined probability of type I and type II errors. Numerical simulations of stratigraphically preserved astronomical signals suggest that optimum significance levels at which to reject a null hypothesis of no astronomical forcing are between 0.01 and 0.001 (i.e., 99-99.9% confidence level). This is lower than commonly employed in the literature (90-99% confidence levels). Nevertheless, in consonance with the emergent view from other scientific disciplines, fixed-value null hypothesis significance testing of power spectra is implicitly ill suited to demonstrating astronomical forcing, and the use of spectral analysis remains a difficult and subjective endeavor in the absence of additional supporting evidence. Abstract Copyright (2016), American Geophysical Union. All Rights Reserved.
Year of Publication: 2016
Research Program: DSDP Deep Sea Drilling Project
IPOD International Phase of Ocean Drilling
ODP Ocean Drilling Program
Key Words: 24 Surficial Geology, Quaternary Geology; Atlantic Ocean; Ceara Rise; Cenozoic; Climate forcing; Cyclostratigraphy; DSDP Site 607; Deep Sea Drilling Project; East Pacific; Equatorial Atlantic; Equatorial Pacific; Errors; IPOD; Leg 108; Leg 111; Leg 138; Leg 154; Leg 162; Leg 94; Marine sedimentation; Mid-Atlantic Ridge; Milankovitch theory; North Atlantic; North Pacific; Northeast Atlantic; Northeast Pacific; Numerical models; ODP Site 663; ODP Site 664; ODP Site 677; ODP Site 846; ODP Site 849; ODP Site 925; ODP Site 980; ODP Site 982; Ocean Drilling Program; Optimization; Orbital forcing; Pacific Ocean; Pleistocene; Quaternary; Rockall Bank; Sedimentation; Sedimentation rates; South Atlantic; South Pacific; Southeast Pacific
Coordinates: N410004 N410005 W0325726 W0325727
S011153 N000627 W0115242 W0231630
N011203 N011209 W0834413 W0834414
N041215 N041216 W0432920 W0432922
Record ID: 2017048000
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data from John Wiley & Sons, Chichester, United Kingdom