A stochastic nonlinear oscillator model for glacial millennial-scale climate transitions derived from ice-core data

• Published in: Nonlinear Processes in Geophysics
• Main Authors: F. Kwasniok, G. Lohmann
• Format: Article in Journal/Newspaper
• Language: English
• Published: Copernicus Publications 2012
• Subjects: Science; Q; Physics; QC1-999; Geophysics. Cosmic physics; QC801-809; Greenland; Greenland ice core; ice core
• Online Access: https://doi.org/10.5194/npg-19-595-2012; https://doaj.org/article/72621f573b7f4be1bf2876bbf6d9c2e6

A stochastic Duffing-type oscillator model, i.e noise-driven motion with inertia in a potential landscape, is considered for glacial millennial-scale climate transitions. The potential and noise parameters are estimated from a Greenland ice-core record using a nonlinear Kalman filter. For the period from 60 to 20 ky before present, a bistable potential with a deep well corresponding to a cold stadial state and a shallow well corresponding to a warm interstadial state is found. The system is in the strongly dissipative regime and can be very well approximated by an effective one-dimensional Langevin equation.