Tidal Forcing NOT using boundaries

[huynhk4]

Hi Everyone,

I'm relatively new to ROMS and I haven't found anything related to the problem I'm having

I would like to generate a tidal force using body force acceleration, NOT boundary forcing. I've only found boundary forcing topics on this forum.

We were able to implement this in an older version of the code (2.1) by changing the wind stress and setting the surface turbulence to the minimum/zero. However, implementing it in this manner has given me errors in the new code. Can anyone help or point me in the right direction?

Thank You!
Kristina

[kate]

What Paul Budgell has done is implement a tidal potential force as part of the pressure gradient computation. In prsgrd32.h after P(i,j,N(ng) is set:

Code: Select all

#ifdef POT_TIDES
          P(i,j,N(ng)) = P(i,j,N(ng)) - g*Ptide(i,j)
#endif

Of course, Ptide has to be passed into the routine when POT_TIDES is defined.

[huynhk4]

Thank you for the help, this sounds like just what I'm looking for! However, I'm having some trouble implementing it. I defined POT_TIDES but encounter errors in adding that bit of code to prsgrd32.h

What do you mean by "Ptide has to be passed into the routine when POT_TIDES is defined"? Perhaps that is where I'm encountering trouble since I have not done anything with Ptide. I also haven't been able to find any documentation on Ptide (except for your comment instance!) so if you could point me in the right direction I'd really appreciate it.

[kate]

Ptide is a tidal potential field, summed from the components (frequencies) of tidal body forcing. You need to have the components in a forcing file that's read in when ROMS starts up. All the bits of ROMS code to go with it are in my branch of roms, available at github. Just search on POT_TIDES to find them.

As for the fields themselves, Paul Budgell has given me the bits to make them, but the fields aren't as smooth as you might expect from simply the astronomical sines and cosines. I can put the bits out on a web site. There are several phases:

• * make an ascii file of your lat/lon
  * edit an input file
  * compile and run a fortran code
  * convert the code's output to ROMS NetCDF

[kate]

All I have on this is now here.