Dynamical regimes and transitions in Plio-Pleistocene Asian monsoon

¹ Department of Mathematics, CB#3250, University of North Carolina - Chapel Hill, NC 27599, USA
² Potsdam Institute for Climate Impact Research - P.O. Box 601203, 14412 Potsdam, Germany, EU
³ Institute of Physics, University of Potsdam - Karl-Liebknecht-Str. 24/25, 14476 Potsdam-Golm, Germany, EU
⁴ Department of Physics, East China Normal University - Shanghai 200241, China
⁵ Department of Electronic and Information Engineering, The Hong Kong Polytechnic University Hunghom Kowloon, Hong Kong
⁶ Department of Physics, Humboldt University Berlin - Newtonstr. 15, 12489 Berlin, Germany, EU

^a malik@pik-potsdam.de

Received: 7 October 2011
Accepted: 20 January 2012

Abstract

We propose a novel approach based on the fluctuation of similarity to identify regimes of distinct dynamical complexity in short time series. A statistical test is developed to estimate the significance of the identified transitions. Our method is verified by uncovering bifurcation structures in several paradigmatic models, providing more complex transitions compared with traditional Lyapunov exponents. In a real-world situation, we apply this method to identify millennial-scale dynamical transitions in Plio-Pleistocene proxy records of the South Asian summer monsoon system. We infer that many of these transitions are induced by the external forcing of the solar insolation and are also affected by internal forcing on Monsoonal dynamics, i.e., the glaciation cycles of the Northern Hemisphere and the onset of the Walker circulation.