Bin Cheng is visiting the Mathematical Institute at Oxford University today (20 May) to give a talk in the Partial Differential Equations Seminar.  The title of the talk is “Analysis of some nonlinear PDEs from multi-scale geophysical applications“.  The talk is regarding PDE systems from geophysical applications with multiple time scales, in which linear skew-self-adjoint operators of size 1/epsilon give rise to highly oscillatory solutions. Analysis is performed in justifying the limiting dynamics as epsilon goes to zero; furthermore, the analysis yields estimates on the difference between the multiscale solution and the limiting solution. The talk will introduce a simple yet effective time-averaging technique which is especially useful in general domains where Fourier analysis is not applicable.