neg. dp (m) problem near the southern open boundary

[Jeongin Kim]

Hi, I made a new domain for north atlantic ocean, and I'm getting neg. dp (m) in about 5-7 days of run when I turn on the nesting option. 

Without the nesting option, it runs pretty well for a few months (I haven't runned a longer period), but whenever I turn on the nesting option, the outcome gives neg. dp(m) near the southern open boundary. 

It's really close to the western edge of the southern open boundary, near the relaxation zone.

Should I modify e-folding dates (Currently 0.1-10 days within 10 grid points, similar to the GOMb0.08 example), or baclin and batrop, etc.?

I've tried several methods from the solution in previous threads, but those didn't work.

And it is okay when I run without nesting, so I guess the problem is related to nesting.

Could you please share your ideas?

My running bathymetry: Grid size 0.08, from GEBCO 2025 (From the GEBCO_2025I2021.nc file you've uploaded recently)
My nesting bathymetry: Grid size 0.08, from GLBb0.08 (09m11, generated similarly with GOM example)

I attached a powerpoint slides for plots of my topologies, nest_rmu_invday.a, ports, etc., for your information.

Many thanks,

Jeongin