Nonlinear Synergies and Multiscale Structural Dynamics in Complex Systems: Theoretical Advances and Applications to Hydroclimate Dynamics

Abstract:

The dynamical evolution of complex coevolving systems is assessed in a novel nonlinear statistical-dynamical framework formally linking nonlinear statistical measures of codependence and emergence with fundamental dynamical interaction laws.

The methodological developments are then used to shed light onto fundamental interactions underlying complex behaviour in hydroclimate dynamics.

For that purpose, a dynamical model is presented predicting evolving hydroclimatic quantities and their distributions under nonlinearly coevolving geophysical processes. The functional model is based on first principles regulating the dynamics of each system constituent and their synergies, therefore its applicability is general and data-independent, not requiring local calibrations. Moreover, it enables the dynamical estimation of hydroclimatic variations in space and time from the given knowledge at different spatiotemporal conditions. This paves the way for a robust physically based prediction of hydroclimatic changes in unmonitored areas.

Validation is achieved by producing, with the dynamical model, a comprehensive spatiotemporal legacy consistent with the observed distributions along with their dynamical and statistical properties and relations. The similarity between simulated and observed distributions is further assessed with robust information-theoretic diagnostics.

This study ultimately brings to light emerging signatures of structural change in hydroclimate dynamics arising from nonlinear synergies across spatiotemporal scales, and contributes to a better dynamical understanding and prediction of spatiotemporal regimes, transitions and extremes. The study further sheds light onto a diversity of emerging properties from harmonic to hyper-chaotic dynamics in hydroclimatic systems.