A Self-Exciting Model of Eddy Formation at Submesoscale

Mine Çağlar; Barış Samed Yakar

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arXiv · 2608.19275

A Self-Exciting Model of Eddy Formation at Submesoscale

Mine Çağlar·Barış Samed Yakar

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Abstract

Ocean eddies are highly dynamic structures marked by frequent splitting and merging events. They exhibit complex spatio-temporal clustering that traditional Poisson models fail to capture. In this paper, a novel spatio-temporal Hawkes process is introduced to model self-exciting eddy fields on the basis of high-frequency ocean flow data. We formulate a triggering kernel that couples the self-excitation intensity with spatial deformation caused by the strain rate magnitude. To characterize the asymptotic behavior of the eddy field, we derive a Volterra integral equation that governs the expected eddy intensity over time and space. We develop an Expectation-Maximization (EM) algorithm that treats the unobserved parent-child relationships as latent branching structures for parameter estimation. We further extend this framework to accommodate a time-varying, non-homogeneous background intensity, modifying both the EM updates and the analytical Volterra solution accordingly. Finally, we propose a two-stage simulation framework utilizing a cluster representation algorithm. The simulated empirical paths of eddy formation are compared together with numerical solution of the Volterra equation for mean rate as validation of the Hawkes model.

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Mine Çağlar, Barış Samed Yakar. 2026-08-18. A Self-Exciting Model of Eddy Formation at Submesoscale. https://arxiv.org/abs/2608.19275

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