Title
Anomaly Detection in Paleoclimate Records Using Permutation Entropy.
Abstract
Permutation entropy techniques can be useful for identifying anomalies in paleoclimate data records, including noise, outliers, and post-processing issues. We demonstrate this using weighted and unweighted permutation entropy with water-isotope records containing data from a deep polar ice core. In one region of these isotope records, our previous calculations (See Garland et al. 2018) revealed an abrupt change in the complexity of the traces: specifically, in the amount of new information that appeared at every time step. We conjectured that this effect was due to noise introduced by an older laboratory instrument. In this paper, we validate that conjecture by reanalyzing a section of the ice core using a more advanced version of the laboratory instrument. The anomalous noise levels are absent from the permutation entropy traces of the new data. In other sections of the core, we show that permutation entropy techniques can be used to identify anomalies in the data that are not associated with climatic or glaciological processes, but rather effects occurring during field work, laboratory analysis, or data post-processing. These examples make it clear that permutation entropy is a useful forensic tool for identifying sections of data that require targeted reanalysisand can even be useful for guiding that analysis.
Year
DOI
Venue
2018
10.3390/e20120931
ENTROPY
Keywords
Field
DocType
paleoclimate,permutation entropy,ice core,anomaly detection
Anomaly detection,Ice core,Paleoclimatology,Outlier,Permutation entropy,Algorithm,Raw data,Polar,Statistics,Conjecture,Mathematics
Journal
Volume
Issue
ISSN
20
12
1099-4300
Citations 
PageRank 
References 
0
0.34
1
Authors
6
Name
Order
Citations
PageRank
Joshua Garland195.25
Tyler R. Jones200.68
Michael Neuder300.34
Valerie Morris400.34
James W. C. White500.68
Elizabeth Bradley610116.27