• Corpus ID: 231855769

A Lagrangian perspective on nonautonomous advection-diffusion processes in the low-diffusivity limit

  title={A Lagrangian perspective on nonautonomous advection-diffusion processes in the low-diffusivity limit},
  author={Daniel Karrasch and Nathanael Schilling},
We study mass preserving transport of passive tracers in the lowdiffusivity limit using Lagrangian coordinates. Over finite-time intervals, the solution-operator of the nonautonomous diffusion equation is approximated by that of a time-averaged diffusion equation. We show that leading order asymptotics that hold for functions [Krol, 1991] extend to the dominant nontrivial singular value. This answers questions raised in [Karrasch & Keller, 2020]. The generator of the time-averaged diffusion… 
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