5.2. Glossary
- AMVs
Atmospheric Motion Vectors
- CCPP
The Common Community Physics Package is a forecast-model agnostic, vetted collection of code containing atmospheric physical parameterizations and suites of parameterizations for use in Numerical Weather Prediction (NWP) along with a framework that connects the physics to the host forecast model.
- CDEPS
The Community Data Models for Earth Predictive Systems repository (CDEPS) contains a set of NUOPC-compliant data components and ESMF-based “stream” code that selectively removes feedback in coupled model systems. In essence, CDEPS handles the static Data Atmosphere (DATM) integration with dynamic coupled model components (e.g., MOM6). The CDEPS data models perform the basic function of reading external data files, modifying those data, and then sending the data back to the CMEPS mediator. The fields sent to the mediator are the same as those that would be sent by an active component. This takes advantage of the fact that the mediator and other CMEPS-compliant model components have no fundamental knowledge of whether another component is fully active or just a data component. More information about DATM is available in the CDEPS Documentation.
- CESM
The Community Earth System Model (CESM) is a fully-coupled global climate model developed at the National Center for Atmospheric Research (NCAR) in collaboration with colleagues in the research community.
- CMEPS
The Community Mediator for Earth Prediction Systems (CMEPS) is a NUOPC-compliant mediator used for coupling Earth system model components. It is currently being used in NCAR’s Community Earth System Model (CESM) and NOAA’s subseasonal-to-seasonal (S2S) coupled system. More information is available in the CMEPS Documentation.
- COM
On operational systems such as WCOSS, this is the name of the directory used to store output files and other data that need to be archived.
- CPHC
Central Pacific Hurricane Center
- CPAC
Central Pacific
- cron
- crontab
- cron table
Cron is a job scheduler accessed through the command-line on UNIX-like operating systems. It is useful for automating workflow tasks. Cron periodically checks a cron table (aka crontab) to see if any tasks are ready to execute. If so, it runs them.
- data assimilation
Data assimilation is the process of combining observations, model data, and error statistics to achieve the best estimate of the state of a system. One of the major sources of error in weather and climate forecasts is uncertainty related to the initial conditions that are used to generate future predictions. Even the most precise instruments have a small range of unavoidable measurement error, which means that tiny measurement errors (e.g., related to atmospheric conditions and instrument location) can compound over time. These small differences result in very similar forecasts in the short term (i.e., minutes, hours), but they cause widely divergent forecasts in the long term. Errors in weather and climate forecasts can also arise because models are imperfect representations of reality. Data assimilation systems seek to mitigate these problems by combining the most timely observational data with a “first guess” of the atmospheric state (usually a previous forecast) and other sources of data to provide a “best guess” analysis of the atmospheric state to start a weather or climate simulation. When combined with an “ensemble” of model runs (many forecasts with slightly different conditions), data assimilation helps predict a range of possible atmospheric states, giving an overall measure of uncertainty in a given forecast.
- DATM
DATM is the Data Atmosphere component of CDEPS. It uses static atmospheric forcing files (derived from observations or previous atmospheric model runs) instead of output from an active atmospheric model. This reduces the complexity and computational cost associated with coupling to an active atmospheric model. The Data Atmosphere component is particularly useful when employing computationally intensive Data Assimilation (DA) techniques to update ocean and/or sea ice fields in a coupled model. In general, use of DATM in place of an active atmospheric component can be appropriate when users are running a coupled model and only want certain components of the model to be active. More information about DATM is available in the CDEPS Documentation.
- DOCN
DOCN is the Data Ocean component of CDEPS. It uses static ocean forcing files (derived from observations or previous ocean model runs) instead of output from an active ocean model. This reduces the complexity and computational cost associated with coupling to an active ocean model. The Data Ocean component is particularly useful when employing computationally intensive Data Assimilation (DA) techniques to update atmospheric fields in a coupled model. In general, use of DOCN in place of an active ocean model (e.g., MOM6 or HYCOM) can be appropriate when users are running a coupled model and only want certain components of the model to be active. More information about DOCN is available in the CDEPS Documentation.
- DWAV
DWAV is the Data Wave component of CDEPS. It uses static wave forcing files (derived from observations or previous wave model runs) instead of output from an active wave model. This reduces the complexity and computational cost associated with coupling to an active wave model. The Data Wave component is particularly useful when employing computationally intensive Data Assimilation (DA) techniques. In general, use of DWAV in place of an active wave model (WW3) can be appropriate when users are running a coupled model and only want certain components of the model to be active. More information about DWAV is available in the CDEPS Documentation.
- dycore
- dynamical core
Global atmospheric model based on fluid dynamics principles, including Euler’s equations of motion.
- EDMF
Eddy-Diffusivity Mass-Flux
- EPAC
Eastern Pacific
- ESMF
Earth System Modeling Framework. The ESMF defines itself as “a suite of software tools for developing high-performance, multi-component Earth science modeling applications.” It is a community-developed software infrastructure for building and coupling models.
- FGAT
First Guess at Approximate Time
- FV3
The Finite-Volume Cubed-Sphere dynamical core (dycore). Developed at NOAA’s Geophysical Fluid Dynamics Laboratory (GFDL), it is a scalable and flexible dycore capable of both hydrostatic and non-hydrostatic atmospheric simulations. It is the dycore used in the UFS Weather Model.
- GDAS
Global Data Assimilation System
- GFDL
- GFS
Global Forecast System. The GFS is a National Centers for Environmental Prediction (NCEP) weather forecast model that generates data for dozens of atmospheric and land-soil variables, including temperatures, winds, precipitation, soil moisture, and atmospheric ozone concentration. The system couples several models (including atmosphere, ocean, land/soil, and sea ice) that work together to accurately depict weather conditions.
- GOES-R
Geostationary Operational Environmental Satellite-R Series
- GRIB2
Gridded Binary 2; the second version of the World Meterological Organization’s (WMO) standard for distributing gridded data.
- HAFS
Hurricane Analysis and Forecast System
- HFSA
Hurricane Forecast System Configuration A
- HFSB
Hurricane Forecast System Configuration B
- HPC
High-Performance Computing
- HPSS
NOAA’s High Performance Storage System (HPSS)
- HYCOM
The HYbrid Coordinate Ocean Model (HYCOM) was developed to address known shortcomings in the vertical coordinate scheme of the Miami Isopycnic-Coordinate Ocean Model (MICOM). HYCOM is a primitive equation, general circulation model with vertical coordinates that remain isopycnic in the open, stratified ocean. However, the isopycnal vertical coordinates smoothly transition to z-coordinates in the weakly stratified upper-ocean mixed layer, to terrain-following sigma coordinates in shallow water regions, and back to z-level coordinates in very shallow water. The latter transition prevents layers from becoming too thin where the water is very shallow. See the HYCOM User’s Guide for more information on using the model. The HYCOM model code is publicly available on GitHub.
- JTWC
Joint Typhoon Warning Center
- Mediator
A mediator, sometimes called a coupler, is a software component that includes code for representing component interactions. Typical operations include merging data fields, ensuring consistent treatment of coastlines, computing fluxes, and temporal averaging.
- MOM
- MOM6
- Modular Ocean Model
MOM6 is the latest generation of the Modular Ocean Model. It is numerical model code for simulating the ocean general circulation. MOM6 was originally developed by the Geophysical Fluid Dynamics Laboratory. Currently, MOM6 code and an extensive suite of test cases are available under an open-development software framework. Although there are many public forks of MOM6, the NOAA EMC fork is used in the UFS Weather Model.
- MP
Microphysics
- NATL
North Atlantic
- NCAR
- NCEP
National Centers for Environmental Prediction (NCEP) is an arm of the National Weather Service consisting of nine centers. More information can be found at https://www.ncep.noaa.gov.
- netCDF
NetCDF (Network Common Data Form) is a file format and community standard for storing multidimensional scientific data. It includes a set of software libraries and machine-independent data formats that support the creation, access, and sharing of array-oriented scientific data.
- NHC
National Hurricane Center
- NIO
Northern Indian Ocean
- NUOPC
- National Unified Operational Prediction Capability
The National Unified Operational Prediction Capability is a consortium of Navy, NOAA, and Air Force modelers and their research partners. It aims to advance the weather modeling systems used by meteorologists, mission planners, and decision makers. NUOPC partners are working toward a common model architecture — a standard way of building models — in order to make it easier to collaboratively build modeling systems.
- NUOPC Layer
The NUOPC Layer “defines conventions and a set of generic components for building coupled models using the Earth System Modeling Framework (ESMF).” NUOPC applications are built on four generic components: driver, model, mediator, and connector. For more information, visit the NUOPC website.
- NWP
Numerical Weather Prediction (NWP) takes current observations of weather and processes them with computer models to forecast the future state of the weather.
- OBSPROC
Observation Processing
- PBL
Planetary Boundary Layer
- RTOFS
Real-Time Ocean Forecast System
- SASAS
Simplified Arakawa-Schubert and Adjusted Sigma
- SH
Southern Hemisphere
- TC
Tropical cyclone
- TKE
Turbulent Kinetic Energy
- UFS
The Unified Forecast System is a community-based, coupled, comprehensive Earth modeling system consisting of several applications (apps). These apps span regional to global domains and sub-hourly to seasonal time scales. The UFS is designed to support the Weather Enterprise and to be the source system for NOAA’s operational numerical weather prediction applications. For more information, visit https://ufscommunity.org/.
- UFS_UTILS
A collection of code used by multiple UFS applications (e.g., HAFS, the UFS Short-Range Weather App, the UFS Medium-Range Weather App). The
chgres_cubecode used by HAFS is part of this collection. The code is publicly available on Github.- UPP
The Unified Post Processor is software developed at NCEP and used operationally to post-process raw output from a variety of NCEP’s NWP models, including the FV3. See https://epic.noaa.gov/unified-post-processor/ for more information.
- Weather Enterprise
Individuals and organizations from public, private, and academic sectors that contribute to the research, development, and production of weather forecast products; primary consumers of these weather forecast products.
- Weather Model
A prognostic model that can be used for short- and medium-range research and operational forecasts. It can be an atmosphere-only model or an atmospheric model coupled with one or more additional components, such as a wave or ocean model. HAFS uses the UFS Weather Model.
- WPAC
Western Pacific
- WW3
- WWIII
- WaveWatch III
WAVEWATCH III (WW3) is a community wave modeling framework that includes the latest scientific advancements in the field of wind-wave modeling and dynamics. The core of the framework consists of the WAVEWATCH III third-generation wave model (WAVE-height, WATer depth and Current Hindcasting), developed at NOAA/NCEP. WAVEWATCH III differs from its predecessors in many important points such as governing equations, model structure, numerical methods, and physical parameterizations. The model code is publicly available on GitHub at https://github.com/NOAA-EMC/WW3.