Potential analysis reveals changing number of climate states during the last 60 kyr

We develop and apply a new statistical method of potential analysis for detecting the number of states of a geophysical system, from its recorded time series. Estimation of the degree of a polynomial potential allows us to derive the number of potential wells in a system. The method correctly detect...

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Bibliographic Details
Main Authors: V. N. Livina, F. Kwasniok, T. M. Lenton
Format: Article in Journal/Newspaper
Language:English
Published: Copernicus Publications 2010
Subjects:
geo
Online Access:http://www.clim-past.net/6/77/2010/cp-6-77-2010.pdf
https://doaj.org/article/a6e7f27e69574c6197c779a67fe9f5a2
Description
Summary:We develop and apply a new statistical method of potential analysis for detecting the number of states of a geophysical system, from its recorded time series. Estimation of the degree of a polynomial potential allows us to derive the number of potential wells in a system. The method correctly detects changes in the number of wells in artificial data. In ice-core proxy records of Greenland paleotemperature, a reduction in the number of climate states from two to one is detected sometime prior to the last glacial maximum (LGM), 23–19 kyr BP. This result is also found in analysis of Greenland Ca data. The bifurcation can be interpreted as loss of stability of the warm interstadial state of the Dansgaard-Oeschger (DO) events. The proposed method can be applied to a wide range of geophysical time series exhibiting bifurcations.