Ocean Modeling Discussion

ROMS/TOMS

Search for:
It is currently Sat Jul 20, 2019 8:34 pm




Post new topic Reply to topic  [ 3 posts ] 

All times are UTC

Author Message
PostPosted: Tue Nov 08, 2011 4:10 pm 
Offline

Joined: Fri Jan 08, 2010 7:22 pm
Posts: 139
Location: Theiss Research
In the current cppdefs ( svn $Id: cppdefs.h 572 2011-10-18 17:56:01Z arango $ ) the pressure gradient options are:

Code:
** Pressure gradient algorithm OPTIONS:                                      **
**                                                                           **
**   If no option is selected, the pressure gradient term is computed using  **
**   standard density Jacobian algorithm. Notice that there are two quartic  **
**   pressure Jacobian options. They differ on how the WENO reconciliation   **
**   step is done and in the monotonicity constraining algorithms.           **
**                                                                           **
** DJ_GRADPS           use if splines density Jacobian (Shchepetkin, 2000)   **
** PJ_GRADP            use if finite volume Pressure Jacobian (Lin,1997)     **
** PJ_GRADPQ2          use if quartic 2 Pressure Jacobian (Shchepetkin,2000) **
** PJ_GRADPQ4          use if quartic 4 Pressure Jacobian (Shchepetkin,2000) **
** WJ_GRADP            use if weighted density Jacobian (Song,1998)          **


In a 2002 paper (Developments in terrain-following ocean models:
intercomparisons of numerical aspects - Ezer, Arango & Shchepetkin) it is shown that ROMS can have an order of magnitude bigger errors than POM (best algorithm vs best algorithm when topography is very steep). In this paper they cite a paper titled A method for computing horizontal pressure-gradient force in an oceanic model with a nonaligned vertical coordinate (which was actually published in 2003 - Shchepetkin & McWilliam).

There is no Shchepetkin 2000 in the bibliography (https://www.myroms.org/wiki/index.php/Bibliography) so I'm wondering if the pressure gradient options in cppdefs.h are the same as the ones described in the 2003 paper.

It seems however that the 2003 paper algorithm was never fully implemented in ROMS-Rutgers
(viewtopic.php?f=14&t=2437&p=9083&hilit=pressure+gradient#p9083)

Are there any plans to implement the 2003 pressure gradient algorithm in ROMS-rutgers?

Is it possible to use the latest pressure gradient algorithms? Are there newer algorithms I am missing?

Or are there any plans for future releases of algorithms that would improve ROMS performance over very steep topography?

Attempts to simulate a realistic continental slope would benefit from these improvements, unfortunately however I am probably not in a position to contribute to this endeavor myself.


Top
 Profile  
Reply with quote  
PostPosted: Wed Nov 09, 2011 1:06 am 
Offline
User avatar

Joined: Fri Nov 14, 2003 4:57 pm
Posts: 185
Shchepetkin, 2000 (also cited in Ezer, Arango, Shchepetkin, 2002) refers to
http://www.atmos.ucla.edu/~alex/ROMS/pgf1A.ps
http://www.atmos.ucla.edu/~alex/ROMS/pgf1B.ps
which are odd and even pages of the same document (these files are designed
to generate a two-sided printout using one-sided black-and-white printer). It was
never formally published, even though algorithms developed there are widely used.


Top
 Profile  
Reply with quote  
PostPosted: Thu Nov 10, 2011 2:46 am 
Offline

Joined: Fri Jan 08, 2010 7:22 pm
Posts: 139
Location: Theiss Research
Thank you Alexander!


Top
 Profile  
Reply with quote  
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 3 posts ] 

All times are UTC


Who is online

Users browsing this forum: No registered users and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
Powered by phpBB® Forum Software © phpBB Group