[MITgcm-support] noise near the boundary

[Yangxin He]

Hi there,


I am running a simple 2D tide over topography simulation. I am using advection scheme 33, Smagorinsky viscosity and pp81 for the vertical viscosity/diffusion. The barotropic tide is forced by obcs package at west and east boundaries.

The simulation is fine overall, but there is significant noise near the eastern boundary. I have attached a plot of horizontal velocity (u(z=0)) at the surface. The y-axis is u(z=0). The x-axis is the number of points. My domain ends at 9500pt and there is a layer of stretched grids between 8500pt to 9500pt. As you can see, the wave has not propagated to the boundary, so why will it have such noise generating at the eastern boundary? Anyone else has this kind of problem?

This noise is not something I cannot live with, but it is a bit annoying and I am afraid there is something apparently wrong going on which I am not aware of.


Thanks


Yangxin
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