ROMS output gradient calculation

[anurag.kumar]

Dear All,

Hope you are doing well.

I wish to initiate again the geostrophic current issue for ocean ROMS community. I am trying to calculate it in Arabian Gulf with 1/120 degree resolution output. I am just curious how we can get gradient of pressure on skew curvilnear grid of ROMS output . My intention is to calculate it with mathematical formula. I did try to get it with by my own mathematical calculation but still getting a lot of differences in actual and geostropic current which seems not good as usual. I have both pressure data on sigma as well as on Z co-ordinate but the the issue is how I can take gradient of pressure field on this non-symmetric lat-lon coordinate.

Anurag

[tompc35]

You could try the XROMS Python package. It has a general function for calculating horizontal derivatives on the native ROMS grid, as well as specialized functions for calculating geostrophic surface velocity and horizontal buoyancy gradients.

https://xroms.readthedocs.io/en/latest/ ... erivatives

[anurag.kumar]

You could try the XROMS Python package. It has a general function for calculating horizontal derivatives on the native ROMS grid, as well as specialized functions for calculating geostrophic surface velocity and horizontal buoyancy gradients.

https://xroms.readthedocs.io/en/latest/ ... erivatives

Thank you for your help. it is really awesome tools. I got derivative of temperature and salt now but I have one more concern regarding the pressure. I have ROMS output data which have no pressure variables and I want to calculate pressure gradient. Have you some idea how can i get it by XROMS tools or by any convenient methods ?