Berlin 2012 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
UP: Fachverband Umweltphysik
UP 11: Methods 2
UP 11.2: Talk
Thursday, March 29, 2012, 09:45–10:00, HFT-FT 131
Complex networks from irregularly sampled time series of palaeo data — •Kira Rehfeld1,2, Norbert Marwan1, Sebastian Breitenbach3, and Jürgen Kurths1,2 — 1Potsdam Institute for Climate Impact Research, Potsdam, Germany — 2Department of Physics, Humboldt University Berlin, Berlin, Germany — 3Department of Earth Sciences, Swiss Federal Institute of Science and Technology (ETH), Zürich, Switzerland
In order to understand regional climate changes in spatially extensive and complex regions, combined information from palaeo archives, such as stalagmites, tree rings and sediment records is necessary. To this end, complex networks present a powerful and increasingly popular tool for the description and analysis of interactions within complex spatially extended systems in the geosciences. Such a network is typically constructed by thresholding a similarity matrix which in turn is based on a set of time series representing the (Earth) system dynamics at different locations. Regarding the pre-instrumental past, information about the system's processes and thus its state is available only through the reconstructed time series which -- most often -- are irregularly sampled in time and space. Interpolation methods introduce strongly sampling-dependent additional errors, thus we use our recently developed methods to quantify linear (Pearson correlation) and non-linear (mutual information) similarity in presence of heterogeneous sampling. We illustrate our approach in the assessment of Holocene Asian monsoon dynamics from stalagmite records.