2. Code Overview

2.1. UFS Weather Model Hierarchical Repository Structure

The UFS Weather Model (WM) repository supports the UFS short- and medium-range weather applications (SRW / MRW Apps). The WM repository contains atmosphere, ocean, sea ice, and wave components, as well as some infrastructure components. Each of these subcomponents has its own repository. All the repositories are currently located in GitHub with public access to the broad community. Table 2.1 describes the list of repositories that comprises the UFS WM.

Table 2.1 List of Repositories that comprise the ufs-weather-model

Repository Description	Authoritative repository URL
Umbrella repository for the UFS Weather Model	https://github.com/ufs-community/ufs-weather-model
Framework to connect the CCPP library to a host model	https://github.com/NCAR/ccpp-framework
CCPP library of physical parameterizations	https://github.com/NCAR/ccpp-physics
Umbrella repository for the physics and dynamics of the atmospheric model (FV3)	https://github.com/NOAA-EMC/fv3atm
FV3 dynamical core	https://github.com/NOAA-GFDL/GFDL_atmos_cubed_sphere
Stochastic physics pattern generator	https://github.com/noaa-psd/stochastic_physics
Modular Ocean Model (MOM6)	https://github.com/NOAA-EMC/MOM6
HYbrid Coordinate Ocean Model (HYCOM)	https://github.com/NOAA-EMC/HYCOM-src
Los Alamos sea ice model (CICE6)	https://github.com/NOAA-EMC/CICE
NOAA/NCEP WAVEWATCH III Model (WW3)	https://github.com/NOAA-EMC/WW3
The Goddard Chemistry Aerosol Radiation and Transport (GOCART)	https://github.com/GEOS-ESM/GOCART
NUOPC Community Mediator for Earth Prediction Systems (CMEPS)	https://github.com/NOAA-EMC/CMEPS
Community Data Models for Earth Prediction Systems (CDEPS)	https://github.com/NOAA-EMC/CDEPS
Air Quality Model (AQM)	https://github.com/NOAA-EMC/AQM

In the table, the left column contains a description of each repository, and the right column shows the component repositories which are pointing to (or will point to) the authoritative repositories. The UFS WM currently uses Git submodules to manage the sub-components.

2.2. Directory Structure

The umbrella repository for the UFS Weather Model is named ufs-weather-model. Under this repository reside a number of submodules that are nested in specific directories under the parent repository’s working directory. When the ufs-weather-model repository is cloned, the basic directory structure will be similar to the example below. Files and some directories have been removed for brevity. Directories in parentheses will appear only after a submodule update (git submodule update --init --recursive).

ufs-weather-model/
├── build.sh                 -------- script for building the WM
├── cmake                    -------- cmake configuration files
├── CMakeLists.txt
├── CMakeModules
├── doc                      -------- User Guide files
├── driver
├── FV3                      -------- UFSAtm atmosphere model
│   ├── (atmos_cubed_sphere) -------- FV3 dynamical core
│   │   ├── (docs)
│   │   ├── (driver)
│   │   ├── (model)
│   │   └── (tools)
│   ├── (ccpp)               -------- Common Community Physics Package
│   │   ├── (config)
│   │   ├── (driver)
│   │   ├── (framework)      -------- CCPP framework
│   │   ├── (physics)        -------- CCPP compliant physics schemes
│   │   └── (suites)         -------- CCPP physics suite definition files (SDFs)
│   ├── (cpl)                -------- Coupling field data structures
│   ├── (io)                 -------- UFSAtm write grid comp code
│   └── (stochastic_physics) -------- Wrapper for stochastic physics
│
├── stochastic_physics       -------- stochastic physics pattern generator
├── AQM
│     └── (src)
│         ├── (model)
│            └── (CMAQ)                         --------- EPA AQ Model
├── CICE-interface
│    └── CICE                                   --------- CICE6 sea ice model
│        ├── (icepack)                          --------- Sea ice column physics
│        └── (cicecore/drivers/nuopc/cmeps)     --------- NUOPC CICE6 cap
├── GOCART
│    └── (ESMF)                                 --------- GOCART model
├── HYCOM-interface
│    └── HYCOM                                  --------- HYCOM ocean model
│        └── (NUOPC)                            --------- NUOPC HYCOM cap
├── MOM6-interface
│    └── MOM6
│        ├── (src)                              --------- MOM6 ocean model
│        └── (config_source/drivers/nuopc_cap)  --------- NUOPC MOM6 cap
├── WW3
│    └── (model)                                --------- WW3 model
│        └── (esmf)                             --------- NUOPC WW3 cap
├── CDEPS-interface
│     └── CDEPS
│         ├── (datm)                            --------- CDEPS DATM
│         └── (docn)                            --------- CDEPS DOCN
├── CMEPS-interface
│    └── CMEPS
│         └── (cesm)                            --------- CMEPS CESM
├── modulefiles          -------- system module files for supported HPC systems
└── tests                -------- regression test infrastructure
    └── parm
    └── tests
    └── fv3_conf

The physics subdirectory in the gfsphysics directory is not used or supported as part of this release (all physics is available through the CCPP using the repository described in Table 2.1).