Sensitivity of Dynamical Coupling to Large-Scale Circulation in European Winter Extremes

The physical mechanisms underlying climate-induced extreme events are inherently complex, arising from the compounding nature of multiple drivers and/or hazards. Leveraging the chaotic nature of the atmosphere, a novel approach, based on results from dynamical system theory, has recently been adopted to reveal the drivers of both individual and compound extremes. Central to this approach is the co-recurrence ratio, which quantifies the instantaneous dynamical coupling between multiple variables in terms of joint recurrences of atmospheric configurations to similar ones in the past.

While the co-recurrence ratio has demonstrated potential in revealing the atmospheric drivers of certain extremes, its performance may depend heavily on factors such as the choice of geographical domain(s), selection of variables, and the thresholds used to define extremes. These sensitivities remain underexplored, limiting the broader applicability of this approach.

In this study, we aim to address these gaps by assessing the sensitivity of the co-recurrence ratio in a European setting, focusing on daily winter extremes in temperature, wind, and precipitation. For this analysis, we adopt a bivariate focus, diagnosing the coupling between large-scale circulation patterns and single hazard variables.

By exploring these sensitivities, this work seeks to enhance the understanding of the robustness of the co-recurrence ratio and its effectiveness in diagnosing the atmospheric drivers of various types of extremes.