Reconstructing Large-scale Variability from Palaeoclimatic Evidence by Means of Data Assimilation Through Upscaling and Nudging(DATUN)

  • Julie M. Jones
  • Martin Widmann
Part of the GKSS School of Environmental Research book series (GKSS)


This chapter describes a newly developed approach for extracting the climate signal from proxy records, termed DATUN (Data Assimilation Through Upscaling and Nudging).

The first half of the paper describes the development of an estimate of the strength of the Austral Summer Antarctic Oscillation using station sea level pressure records for the period 1878–1985, the first to our knowledge. To extend this record further back, a estimate using tree-ring chronologies back to 1743 has also been undertaken. Comparison of the two estimates shows moderate agreement on interannual and decadal timescales, but the comparison also points towards the inherent uncertainties of proxy-based climate reconstructions.

The background to, and theory behind, assimilation of large-scale climate patterns in general circulation models using pattern nudging are then explained. First results of nudging towards prescribed states of the Arctic Oscillation are shown.


Empirical Orthogonal Function Principal Component Regression Proxy Data Tree Ring Chronology Antarctic Oscillation 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.

Copyright information

© Springer-Verlag Berlin Heidelberg 2004

Authors and Affiliations

  1. 1.Institute for Coastal ResearchGKSS Research CentreGeesthachtGermany

Personalised recommendations