NG41B-05:
A Data-based Low-dimensional Stochastic Model of the NGRIP delta-O18 with Built-in Delays
Thursday, 18 December 2014: 9:00 AM
Dmitri A Kondrashov1, Honghu Liu1, Mickael Chekroun1, Anders Svensson2, Denis-Didier Rousseau3 and Michael Ghil1, (1)University of California Los Angeles, Atmos. Sci, Los Angeles, CA, United States, (2)Centre for Ice and Climate, Copenhagen, Denmark, (3)CNRS, Paris Cedex 16, France
Abstract:
We used a high-resolution delta-O18 record from the North Greenland Ice Core Project (NGRIP) to derive a low-dimensional inverse stochastic model of this record. The model reproduces well the record’s visual features, its probability density function and its lag-correlation function. The model’s deterministic part needs to include explicitly several lags in order to achieve these properties of the delta-O18 variations. The relevance of the memory effects captured by these lagged dependencies, along with their physical interpretation, will be discussed from a theoretical perspective based on the Mori-Zwanzig formalism of statistical mechanics.
