| 3D-Var | Three-Dimensional Variational data assimilation |
| 4D-EnVar | Four-Dimensional Ensemble-Variational data assimilation |
| 4D-Var | Four-Dimensional Variational data assimilation |
| ABL | atmospheric boundary layer |
| ABOM | Australian Bureau of Meteorology |
| AeroNet | Aerosol Robotic Network |
| AFWA | Air Force Weather Agency |
| AIRS | Atmospheric Infrared Sounder |
| AMDAR | Aircraft Meteorological Data Relay |
| AMMA | African Monsoon Multidisciplinary Analysis |
| AMS | American Meteorological Society |
| AMSR-E | advanced microwave scanning radiometer |
| AMSU | Advanced Microwave Sounding Unit |
| AMV | atmospheric motion vector |
| AMY | Asian Monsoon Year |
| ANOVA | analysis of variance |
| AO | Atlantic Oscillation |
| APCC | APEC (Asia-Pacific Economic Cooperation) Climate Center |
| ASCAT | Advanced Scatterometer |
| AUV | autonomous underwater vehicle |
| BSISO | Boreal Summer Intraseasonal Oscillation |
| CBS | Commission for Basic Systems |
| CESM | Community Earth System Model |
| CFS | Climate Forecast System |
| CFSR | Climate Forecast System Reanalysis |
| CFSv2 | Climate Forecast System version 2 |
| CIME | Common Infrastructure for Modeling the Environment |
| CliPAS | Climate Prediction and its Application to Society |
| CMC | Canadian Meteorological Centre |
| CMIP | Coupled Model Intercomparison Project |
| COAMPS | Coupled Ocean/Atmosphere Mesoscale Prediction System |
| CODAR | Coastal Ocean Dynamics Applications Radar |
| CPC | Climate Prediction Center |
| CPT | Climate Process Team |
| CPTEC | Brazil Center for Weather Forecasting and Climate Studies |
| CrIS | Crosstrack Infrared Sounder |
| CYGNSS | Cyclone Global Navigation Satellite System |
| DA | data assimilation |
| DARPA | Defense Advanced Research Projects Agency |
| DEMETER | Development of a European Multi-model Ensemble system for seasonal to inTERannual predictions |
| DHS | U.S. Department of Homeland Security |
| DO | Dynamically Orthogonal |
| DOD | U.S. Department of Defense |
| DOE | U.S. Department of Energy |
| DTRA | Defense Threat Reduction Agency |
| DWH | Deepwater Horizon |
| DYNAMO | Dynamics of the Madden-Julian Oscillation |
| ECMWF | European Centre for Medium-Range Weather Forecasts |
| ECOSTRESS | ECOsystem Spaceborne Thermal Radiometer Experiment on Space Station |
| EnKF | Ensemble Kalman Filter data assimilation |
| ENSEMBLES | European Commission FP7 project |
| ENSO | El Niño-Southern Oscillation |
| ERA Interim | ECMWF Interim Reanalysis |
| ESM | Earth system model |
| ESMF | Earth System Modeling Framework |
| ESPC | Earth System Modeling Capability |
| ET-OPSLS | Expert Team on Operational Predictions from Subseasonal to Longer-time Scales |
| EUMETSAT | European Organisation for the Exploitation of Meteorological Satellites |
| FNMOC | Fleet Numerical Meteorology and Oceanography Center |
| GATE | GARP (Global Atmosphere Research Program) Atlantic Tropical Experiment |
| GDP | Global Drifter Program |
| GEFS | Global Ensemble Forecast System |
| GFDL | Geophysical Fluid Dynamics Laboratory |
| GHG | greenhouse gas |
| GLDAS | Global Land Data Assimilation System |
| GMM | Gaussian Mixture Model |
| GOES | Geostationary Operational Environmental Satellite |
| GPM | Global Precipitation Mission |
| GPS | global positioning system |
| GPS-RO | Global Positioning System Radio Occulation |
| GTH | Global Tropics Hazards and Benefits Assessment |
| HadGEM3 | Hadley Centre Global Environment Model version 3 |
| HPC | high-performance computing |
| IASI | Infrared Atmospheric Sounding Interferometer |
| ICESat2 | Second generation Ice Cloud and Land Elevation Satellite |
| IFS | Integrated Forecast System |
| IGIM | Interagency Group on Integrative Modeling |
| IMAAC | Interagency Modeling and Atmospheric Assessment Center |
| IMD | India Meteorology Department |
| IOD | Indian Ocean Dipole |
| IOOS | Integrated Ocean Observing System |
| IOP | intensive observing period |
| IPCC | Intergovernmental Panel on Climate Change |
| IRI | International Research Institute for Climate and Society |
| ISI | intraseasonal to interannual |
| ISS | International Space Station |
| ITCZ | Inter Tropical Convergence Zone |
| JAXA | Japan Aerospace Exploration Agency |
| JEDI | Joint Effort for Data Assimilation Integration |
| JMA | Japan Meteorological Agency |
| JPL | Jet Propulsion Laboratory |
| KL | Karhunen-Loève |
| LANL | Los Alamos National Laboratory |
| LDAS | Land Data Assimilation System |
| LES | Large-eddy simulation |
| LIS | Land Information System |
| LSM | land-surface model |
| MCMC | Markov chain Monte Carlo |
| MERIT | Meningitis Environmental Research Information Technologies |
| MIZ | Marginal Ice Zone |
| MJO | Madden-Julian Oscillation |
| MME | multi-model ensemble |
| MODIS | Moderate Resolution Imaging Spectroradiometer |
| MOS | model output statistics |
| MOSAiC | Multidisciplinary drifting Observatory for the Study of Arctic Climate |
| MPI | Message Passing Interface |
| MPLNet | Micro-Pulse Lidar Network |
| NAM | Northern Annular Mode |
| NAO | North Atlantic Oscillation |
| NARAC | National Atmospheric Release Advisory Center |
| NASA | National Aeronautics and Space Administration |
| NASCar | Northern Arabian Sea Circulation—autonomous research |
| NAVGEM | NAVy Global Environmental Model |
| NAVO | Naval Oceanographic Office |
| NCAR | National Center for Atmospheric Research |
| NCEP | National Centers for Environmental Prediction |
| NEMO | Nucleus for European Modelling of the Ocean |
| NEPTUNE | Navy Environmental Prediction sysTem Utilizing the NUMA corE |
| NGGPS | Next Generation Global Prediction System |
| NISAC | National Infrastructure Simulation and Analysis Center |
| NMME | North American Multi-Model Ensemble |
| NOAA | National Oceanic and Atmospheric Administration |
| NRL | Naval Research Laboratory |
| NSF | National Science Foundation |
| NUMA | Nonhydrostatic Unified Model of the Atmosphere DG core |
| NVM | non-volatile memory |
| NWP | numerical weather prediction |
| NWS | U.S. National Weather Service |
| OAR | Office of Oceanic & Atmospheric Research |
| OLR | outgoing longwave radiation |
| ONR | Office of Naval Research |
| OOPS | Object Oriented Programming System |
| OpenMP | Open Multi-Processing |
| OSSE | Observing System Simulation Experiment |
| PCAST | President’s Council of Advisors on Science and Technology |
| PDE | partial differential equation |
| PIM | processor in memory |
| PinT | parallel in time |
| PIO | Parallel I/O |
| PNA | Pacific North American teleconnection pattern |
| QBO | Quasi-Biennial Oscillation |
| R2O | research to operations |
| RISA | Regional Integrated Sciences and Assessments Program |
| RMM | Real-time Multivariate MJO index |
| RMSE | root mean square error |
| S2S | subseasonal to seasonal |
| SAON | Sustaining Arctic Observing Network |
| SBIR | Small Business Innovation Research |
| SHEBA | Surface Heat Budget of the Arctic Ocean |
| SMAP | Soil Moisture Active Passive |
| SMIP-2 | Seasonal Prediction Model Intercomparison Project |
| SMOS | Soil Moisture and Ocean Salinity |
| SNOTEL | Snowpack Telemetry |
| SOCRATES | Southern Ocean Clouds, Radiation, Aerosol Transport Experimental Study |
| SPERR | Scientific Partnerships Enabling Rapid Response |
| SPURS-2 | Salinity Processes in the Upper Ocean Regional Study 2 |
| SSD | Solid State Devices |
| SSH | sea surface height |
| SSM/I | Special Sensor Microwave Imager |
| SST | sea surface temperature |
| SSW | sudden stratospheric warning |
| SWE | snow water equivalent |
| SWOT | Surface Water and Ocean Topography |
| TAMDAR | Tropospheric Airborne Meteorological Data Reporting |
| TAO/TRITON | Tropical Atmosphere Ocean/Triangle Trans-Ocean Buoy Network |
| TCWB | Taiwan Central Weather Bureau |
| THORPEX | The Observing system Research and Predictability Experiment |
| TIGGE | THORPEX Interactive Grand Global Ensemble |
| TIROS | Television Infrared Observation Satellite |
| TOGA COARE | Tropical Ocean Global Atmosphere Coupled Ocean-Atmosphere Response Experiment |
| TPOS | Tropical Pacific Observing System |
| TRMM | Tropical Rainfall Measuring Mission |
| UKMO | United Kingdom Met Office |
| USDA | U.S. Department of Agriculture |
| USGCRP | U.S. Global Change Research Program |
| VAD | Velocity Azimuth Display |
| VES | Virtual Earth System |
| VOCALS-Rex | VAMOS (Variability of the American Monsoon Systems) Ocean-Cloud-Atmosphere-Land Study Regional Experiment |
| WCRP | World Climate Research Programme |
| WCS | World Climate Service |
| WERA | WavE RAdar |
| WGNE | Working Group on Numerical Experimentation |
| WHO | World Health Organization |
| WMO | World Meteorological Organization |
| WWRP | World Weather Research Programme |
| XBT | Expendable Bathythermograph |
| YMC | Years of the Maritime Continent |
| YOPP | Year of Polar Prediction |
| YOTC | Year of Tropical Convection |