TOP interface User Quick Guide (NEMO 4.0+)

TOP interface structure

TOP (Tracers in the Ocean Paradigm) is the NEMO hardwired interface toward biogeochemical models and provide the physical constraints/boundaries for oceanic tracers. It consists of a modular framework to handle multiple ocean tracers, including also a variety of built-in modules. TOP interfaces has the following location in the code repository

<repository>/NEMOGCM/NEMO/TOP_SRC/

and the following modules are available:

TRP : Interface to NEMO physical core for computing tracers transport CFC : Inert carbon tracers (CFC11,CFC12, SF6) C14 : Radiocarbon passive tracer AGE : Water age tracking MY_TRC : Template for creation of new modules and external BGC models coupling PISCES : Built in BGC model

The usage of TOP is done by i) including in the configuration definition the component “TOP_SRC” and ii) adding the macro key_top in the configuration cpp file.

As an example, the user can refer to simplest configurations already available in the code GYRE_BFM or GYRE_PISCES.

Note that, since version 4.0, TOP interface core functionalities are activated by means of logical keys and all process-specific pre-processing macros from previous versions were removed.

TOP namelist Walkthrough

Here below are listed the features/options of the TOP interface accessible through the namelist_top_ref and modifiable by means of namelist_top_cfg (as for NEMO physical ones).