Running a proper pressure gradient error test

General scientific issues regarding ROMS

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lcbernardo
Posts: 88
Joined: Wed Oct 01, 2014 8:57 pm
Location: International Coastal Research Center

Running a proper pressure gradient error test

#1 Unread post by lcbernardo »

Hi everyone. As my modelling study sites often feature complex bathymetric features, I would like to learn more about properly running a pressure gradient error test. And although I have a general idea after reading many posts about it, I'd like to clear up some of my confusions about it, which are the following?

-When doing a pressure gradient error test, what is meant by having 'no forcing'? Does this mean closing all the open boundaries? Or does this mean prescribing temperature and salinity values constant in time (with zero velocities)?

-Which kind of initial temperature and salinity conditions would be ideal to use? Would homogeneous conditions suffice, or must there necessarily be some kind of stratification with depth?

-I've also read that using analytical functions to prescribe the necessary conditions for the pressure gradient error test is recommended, but I'm more used to modifying input and boundary condition netcdf files using MATLAB and other programs. Will I still be able to properly run the test if so?

I would greatly appreciate any help or insights. Thanks!

Lawrence

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kate
Posts: 4088
Joined: Wed Jul 02, 2003 5:29 pm
Location: CFOS/UAF, USA

Re: Running a proper pressure gradient error test

#2 Unread post by kate »

All I know is from reading Beckmann and Haidvogel back in the day.

No forcing meant no wind stress. Whatever the boundary conditions, you don't want
them to be driving a circulation. You can let temperature and salt evolve. Aike
showed that you need stratification, but it should be a uniform nonlinear function of z
throughout the domain.

lcbernardo
Posts: 88
Joined: Wed Oct 01, 2014 8:57 pm
Location: International Coastal Research Center

Re: Running a proper pressure gradient error test

#3 Unread post by lcbernardo »

Thanks for your advice Kate! I'll study the paper then for starters, and see how I can proceed.

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