Difference between revisions of "Nemo"

Revision as of 19:38, 9 November 2007

Welcome to the Bristol Nemo Page!

Here are a few tips and comments based on Bristol's experiences compiling and running NEMO. Hopefully, you will find some useful.

Please take a look the official NEMO webpage before continuing with this page.

Projects using Nemo at Bristol

Mediterranean Sea

Amundsen Sea

Thinning of the Pine Island Glacier, West Antarctica, has been observed during the 1990s. It has been suggested that relatively warm water at the base of the ice shelf has triggered the thinning. The source of and mechanism driving this warm water is unknown.

We are constructing a regional model of the Amunsden Sea using Nemo to investigate ocean circulation close to Pine Island Bay. Input data at the sea surface and at the open boundaries are constructed using output data from the OCCAM global ocean model.

ORCA2_LIM test case

Nemo provides a test case, ORCA2_LIM, for a global ocean run coupled with the sea-ice model. The run simulates one year.

The configuration for ORCA2_LIM is downloaded through CVS when getting Nemo and the necessary forcing files are provided through a link on the Nemo website.

Region model

How to set up a regional model starting from the ORCA2_LIM test case:

Create a new configuration for the regional model.
- In directory modipsl/config/ create a new directory AMUNDSEN, for example, and copy the contents of the ORCA2_LIM directory into AMUNDSEN.
- Edit file fait_config in modipsl/modeles/UTIL/. Add \n AMUNDSEN to LIST = and add the line set -A DIR_AMUNSDEN OPA_SRC C1D_SRC NST_SRC.
Change CPP keys by editing BB_make.ldef in modipsl/config/AMUNDSEN/scripts/. Remove key_orca_r2 since you're not running a global model and add key_obc to invoke open boundary conditions instead.
TIP: modify tradmp.F90 in modipsl/modeles/NEMO/OPA_SRC/TRA/. Replace the line if (cp_cfg=="orca" .AND. (ndmp > 0 .OR. ndmp==-1)) then with if (ndmp > 0 .OR. ndmp==-1) then. If you don't make the change you'll get the error message tra_dmp: You should not have seen this print error?. With this change you can apply tracer damping as in the ORCA configurations (i.e. global models for various resolutions) without special treatment for particular areas such as the Meditarrean

Open boundary conditions

Wiki example

This text is very imprtant. This is less so.

Listen very carefully, I shall say this only once:

put kettle on
find mug
add water to tea bag--in mug!

slurp
read
slurp

can be done in any order

An external link is a search engine

A link to another wiki page is the genie project

@@ Line 34: / Line 34: @@
 #* Edit file '''fait_config''' in modipsl/modeles/UTIL/. Add <code>\n AMUNDSEN</code> to <code>LIST =</code> and add the line <code>set -A DIR_AMUNSDEN OPA_SRC C1D_SRC NST_SRC</code>.
 # Change CPP keys by editing '''BB_make.ldef''' in modipsl/config/AMUNDSEN/scripts/. Remove <code>key_orca_r2</code> since you're not running a global model and add <code>key_obc</code> to invoke [[open boundary conditions]] instead.
+# '''TIP''': modify '''tradmp.F90''' in modipsl/modeles/NEMO/OPA_SRC/TRA/. Replace the line <code>if (cp_cfg=="orca" .AND. (ndmp > 0 .OR. ndmp==-1)) then </code> with <code>if (ndmp > 0 .OR. ndmp==-1) then</code>. If you don't make the change you'll get the error message <code>tra_dmp: You should not have seen this print error?</code>. With this change you can apply tracer damping as in the ORCA configurations (i.e. global models for various resolutions) without special treatment for particular areas such as the Meditarrean
 ==Open boundary conditions==