Atmosphere Ocean Science Colloquium

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Exploring Climate Variability through Complex and Dynamical systems

Speaker: Fabrizio Falasca, Courant

Location: 60 Fifth Avenue 7th Floor Open Space

Date: Wednesday, March 22, 2023, 2:30 p.m.

Synopsis:

The Earth’s climate is a complex system composed of many sub-components, interacting with each other across a vast range of spatial and temporal scales. Quantifying the response of such a system to natural and anthropogenic external forcing is a central challenge of contemporary science. To pursue this line of research, climate scientists have focused on hierarchies of models and theories. The recent exponential growth of climate data, combined with advances in statistical learning, data mining and physical insights offer opportunities to further understand and characterize climate dynamics. In this talk I will present strategies to simplify the description of spatiotemporal climate fields through the lens of complex and dynamical systems. This line of research often requires to first reduce the dimensionality of spatiotemporal climate fields into spatially contiguous patterns (i.e., regions). Such patterns can then be thought of as nodes in a complex network. Their linkages, physically caused by atmospheric/oceanic coupled phenomena, can then be inferred through statistical methodologies. Finally, I will focus on a novel methodology for causal inference from time series stemming from linear response theory and fluctuation dissipation relation (FDR). Such causal framework, together with suitable dimensionality
reduction techniques, allows to quantify the response of a spatiotemporal system to local perturbations directly from data. I will showcase a first application to characterize large scale dynamics in the Tropical Pacific basin. The end of the talk will focus on challenges and opportunities for future work.