WP2: Interacting Networks

We propose to develop a framework for studying interacting networks. It will consist of various well-defined models of network interactions, new tools for characterisation and classification of coupled networks, simulation and numerical methods, as well as analytical tools based on percolation theory and generating functions for studying the robustness of interacting networks. By applying this framework to study structural and dynamical properties of coupled networks as well as the influence of structural properties on dynamics, we expect, based on preliminary results, to find significantly different features of these properties, compared to a single network. Due to the coupling between networks we expect to identify new physical laws and scaling behaviours, differing from those found recently for single networks. This acquired knowledge in the context of climate systems provides a completely new toolbox for theory and analysis of climate systems. The specific objectives of WP2 are: 1) the study of the hierarchy of dynamical climate systems such as different time scales, which be viewed as several separate networks embedded in the same space. We will focus on how the different time scale networks interact with each other; 2) we will explore how networks representing different atmospheric layers and different climatological fields (e.g. air and ocean temperatures, pressures and precipitation) interact with each other. Our proposed framework of networks and interacting networks will provide new predictions of possible dynamics such as cascades, new stability patterns, and formation of autonomous clusters; 3) we will test these predictions for climate systems which are known to be coupled (which provides coupling between WP2 and WP3 and WP4). We believe that this innovative point of view will lead to a better understanding of complex climate phenomena such as El NiƱo.