2. Technical Overview
2.1. Prerequisites
2.1.1. Minimum System Requirements
UFS applications, models, and components require a UNIX-based operating system (i.e., Linux or MacOS).
Additionally, users will need:
Disk space: ~23GB (11GB for Land DA System [or 6.5GB for Land DA container], 11GB for Land DA data, and ~1GB for staging and output)
6 CPU cores (or option to run with “oversubscribe”)
2.1.2. Software Prerequisites
The Land DA System requires:
An MPI implementation
A Fortran compiler
Python
Lmod
These software prerequisites are pre-installed in the Land DA container and on other Level 1 systems (see below for details). However, users on non-Level 1 systems will need to install them.
Before using the Land DA container, users will need to install Singularity and an Intel MPI (available free here).
2.2. Supported Systems for Running Land DA
Four levels of support have been defined for UFS applications, and the Land DA System operates under this paradigm:
Level 1 (Pre-configured): Prerequisite software libraries are pre-built and available in a central location; code builds; full testing of model.
Level 2 (Configurable): Prerequisite libraries are not available in a centralized location but are expected to install successfully; code builds; full testing of model.
Level 3 (Limited-test platforms): Libraries and code build on these systems, but there is limited testing of the model.
Level 4 (Build-only platforms): Libraries and code build, but running the model is not tested.
2.2.1. Level 1 Systems
Preconfigured (Level 1) systems for Land DA already have the required external libraries available in a central location via spack-stack and JEDI’s fv3-bundle. Land DA is expected to build and run out-of-the-box on these systems, and users can download the Land DA code without first installing prerequisite software. With the exception of the Land DA container, users must have access to these Level 1 systems in order to use them.
Platform |
Compiler/MPI |
spack-stack & fv3-bundle Installations |
|---|---|---|
Hera |
intel/2022.1.2 / impi/2022.1.2 |
/scratch1/NCEPDEV/nems/role.epic/spack-stack/envs/landda-release-1.0-intel /scratch1/NCEPDEV/nems/role.epic/contrib/fv3-bundle |
Orion |
intel/2022.1.2 / impi/2022.1.2 |
/work/noaa/epic-ps/role-epic-ps/spack-stack/envs/landda-release-1.0-intel /work/noaa/epic-ps/role-epic-ps/contrib/fv3-bundle |
Container |
intel-oneapi-compilers/2021.8.0 / intel-oneapi-mpi/2021.8.0 |
/opt/spack-stack/ (inside the container) /opt/fv3-bundle (inside the container) |
2.2.2. Level 2-4 Systems
On non-Level 1 platforms, the Land DA System can be run within a container that includes the prerequisite software; otherwise, the required libraries will need to be installed as part of the Land DA build process. Once these prerequisite libraries are installed, applications and models should build and run successfully. However, users may need to perform additional troubleshooting on Level 3 or 4 systems since little or no pre-release testing has been conducted on these systems.
Note
Running on Jet, Cheyenne, and NOAA Cloud systems is supported via container.
2.3. Code Repositories and Directory Structure
2.3.1. Directory Structure
The main repository for the Land DA System is named land-offline_workflow;
it is available on GitHub at https://github.com/NOAA-EPIC/land-offline_workflow/.
A number of submodules are nested under the main land-offline_workflow directory.
When the release/public-v1.0.0 branch of the land-offline_workflow repository
is cloned with the --recursive argument, the basic directory structure will be
similar to the example below. Some files and directories have been removed for brevity.
land-offline_workflow
├── DA_update
│ ├── add_jedi_incr
│ ├── jedi/fv3-jedi
│ └── do_LandDA.sh
├── cmake
├── configures
├── docs
├── modulefiles
├── test
├── ufs-land-driver
│ └── ccpp-physics
├── vector2tile
├── CMakeLists.txt
├── README.md
├── LICENSE
├── do_submit_cycle.sh
├── release.environment
├── settings_DA_*
├── submit_cycle.sh
└── template.*
2.3.2. Land DA Components
Table 2.1 describes the various subrepositories that form the UFS Land DA System.
Repository Name |
Repository Description |
Authoritative repository URL |
|---|---|---|
land-DA_update |
Contains scripts and components for performing data assimilation (DA) procedures. |
|
– land-apply_jedi_incr |
Contains code that applies the
JEDI-generated DA increment to UFS
|
|
ufs-land-driver |
Repository for the UFS Land Driver |
|
– ccpp-physics |
Repository for the Common Community Physics Package (CCPP) |
|
land-vector2tile |
Contains code to map between the vector format used by the Noah-MP offline driver, and the tile format used by the UFS atmospheric model. |