2. Global Workflow Components

The global-workflow is a combination of several components working together to prepare, analyze, produce, and post-process forecast data.

The major components of the system are:

Workflow
Pre-processing
Analysis
Forecast
Post-processing
Verification

The Global Workflow repository contains the workflow and script layers. External components will be checked out as git submodules. All of the submodules of the system reside in their respective repositories on GitHub.

2.1. Component repositories

Components included as submodules:

GFS UTILS (https://github.com/ufs-community/gfs_utils): Utility codes needed by Global Workflow to run the GFS configuration
UFS-Weather-Model (https://github.com/ufs-community/ufs-weather-model): This is the core model used by the Global-Workflow to provide forecasts. The UFS-weather-model repository is an umbrella repository consisting of cooupled component earth systeme that are all checked out when we check out the code at the top level of the repoitory
GSI (https://github.com/NOAA-EMC/GSI): This is the core code base for atmospheric Data Assimilation
GSI UTILS (https://github.com/NOAA-EMC/GSI-Utils): Utility codes needed by GSI to create analysis
GSI Monitor (https://github.com/NOAA-EMC/GSI-Monitor): These tools monitor the GSI package’s data assimilation, detecting and reporting missing data sources, low observation counts, and high penalty values
GDAS (https://github.com/NOAA-EMC/GDASApp): Jedi based Data Assimilation system. This system is currently being developed for marine Data Assimilation and in time will replace GSI for atmospheric data assimilation as well
UFS UTILS (https://github.com/ufs-community/UFS_UTILS): Utility codes needed for UFS-weather-model
wxflow (https://github.com/NOAA-EMC/wxflow): Collection of python utilities for weather workflows
Verif global (https://github.com/NOAA-EMC/EMC_verif-global): Verification package to evaluate GFS parallels. It uses MET and METplus. At this moment the verification package is limited to providing atmospheric metrics only

Note

When running the system in forecast-only mode the Data Assimilation components are not needed and are hence not built.

2.2. External dependencies

2.2.1. Libraries

All the libraries that are needed to run the end to end Global Workflow are built using a package manager. These are served via spack-stack. These libraries are already available on supported NOAA HPC platforms.

Find information on official installations of spack-stack here:

https://github.com/JCSDA/spack-stack/wiki/Porting-spack-stack-to-a-new-system

2.2.2. Observation data (OBSPROC/prep)

2.2.2.1. Data

Observation data, also known as dump data, is prepared in production and then archived in a global dump archive (GDA) for use by users when running cycled experiments. The GDA (identified as $DMPDIR in the workflow) is available on supported platforms and the workflow system knows where to find the data.

Hera: /scratch1/NCEPDEV/global/glopara/dump
Orion/Hercules: /work/noaa/rstprod/dump
Jet: /mnt/lfs4/HFIP/hfv3gfs/glopara/dump
WCOSS2: /lfs/h2/emc/global/noscrub/emc.global/dump
S4: /data/prod/glopara/dump

2.2.2.1.1. Global Dump Archive Structure

The global dump archive (GDA) mimics the structure of its production source:

GDAS/GFS: DMPDIR/gdas[gfs].PDY/CC/atmos/FILES
RTOFS: DMPDIR/rtofs.PDY/FILES

The GDA also contains special versions of some datasets and experimental data that is being evaluated ahead of implementation into production. The following subfolder suffixes exist:

SUFFIX	WHAT
nr	Non-restricted versions of restricted files in production. Produced in production. Restriced data is fully stripped from files. These files remain as is.
ur	Un-restricted versions of restricted files in production. Produced and archived on a 48hrs delay. Some restricted datasets are unrestricted. Data amounts: restricted > un-restricted > non-restricted Limited availability. Discontinued producing mid-2023.
x	Experimental global datasets being evaluated for production. Dates and types vary depending on upcoming global upgrades.
y	Similar to “x” but only used when there is a duplicate experimental file in the x subfolder with the same name. These files will be different from both the production versions (if that exists already) and the x versions. This suffix is rarely used.
p	Pre-production copy of full dump dataset, as produced by NCO during final 30-day parallel ahead of implementation. Not always archived.

2.2.2.2. Data processing

Upstream of the global-workflow is the collection, quality control, and packaging of observed weather. The handling of that data is done by the OBSPROC group codes and scripts. The global-workflow uses two packages from OBSPROC to run its prep step to prepare observation (dump) data for use by the analysis system:

Package versions and locations on supported platforms are set in the global-workflow system configs, modulefiles, and version files.