Information about NCOM Release 1.3

NCAR CSM Ocean Model

June 1997

NCAR CSM Ocean Model (NCOM 1.3)

A primitive-equation ocean model upgraded by the

NCAR Oceanography Section

National Center for Atmospheric Research *

PO Box 3000, Boulder, CO 80307

This model is based upon, but differs substantially from the

GFDL Modular Ocean Model (MOM 1.1)

which was implemented by

R.C. Pacanowski K. Dixon A. Rosati

Geophysical Fluid Dynamics Laboratory /NOAA

Princeton, NJ. 08542

based on the work of

Kirk Bryan: A numerical method for the study of the of the

circulation world ocean: 1969, J. Computat. Phys 4 347-376


the invaluable work of Mike Cox & Bert Semtner on earlier

fortran implementations.


Substantial changes to MOM 1.1 have been made in the NCOM, and present MOM 1.1 users should be alert to such changes and familiarize themselves with the many differences. The user should pay particular attention to the added model features and to the list of preprocessor options: many of the MOM 1.1 options have been removed (see checks.F), and several new options have been added. Many of these differences have been noted where they occur in the code, but it was impractical to mark all such differences.


Documentation of the NCOM is available in the NCAR technical note referenced below. Hard-copies of the technical note were distributed at the May 1996 and June 1997 CSM Workshops; electronic copies are available from the NCOM website (see url below).

The NCOM user is encouraged to periodically check our website for code updates and announcements. Several new and updated links were added in June, 1997 when NCOM 1.3 was officially released.

General Notes on NCOM

Description of Distribution Contents

The NCOM distribution (ocn_public_1.3.tar.gz) consists of the NCOM 1.3 Fortran source code and a collection of shell scripts. An ascii file with a diagram of the ocn_public_1.3 structure is available here.