| Numeric |
| 1D-Var | One-dimensional variational analysis |
| 3D-Var | Three-dimensional variational analysis |
| 4D-Var | Four-dimensional variational analysis |
| A |
| AAPP | ATOVS and AVHRR processing package |
| ADD | Architectural Design Document |
| AFG | Administration and Finance Group (of EUMETSAT) |
| AIRS | Atmospheric Infrared Sounder |
| AMSU | Advanced Microwave Sounding Unit |
| AMV | Atmospheric motion vector (satellite wind) |
| A/S | Anti-Spoofing (a mode that the GPS satellites are usually in, which
degrades the accuracy of pseudorange and carrier phase on the L2 signal) |
| ASCAT | Advanced Scatterometer |
| ARS | Assisted Raw Sampling |
| ATOVS | Advanced TOVS |
| AVHRR | Advanced Very High Resolution Radiometer (for visible and infrared imagery, flown in polar orbit) |
| B |
| BUFR | Binary Universal Form for the Representation of meteorological data (A WMO standard data format for weather observations) |
| C |
| C/NOFS | Communications/Navigation Outage Forecasting System |
| CA | Cooperation Agreements |
| CDAAC | The COSMIC Data Analysis and Archive Center |
| CDOP | Continous Development andn Operations Phase |
| CGMS | Coordination Group for Meteorological Satellites |
| CGS | Core Ground Segment |
| CHAMP | Challenging Mini--Satellite Payload |
| CM | Configuration Management |
| CM SAF | Climate Monitoring SAF |
| CMP | Configuration Management Plan |
| CNES | Centre National d'Etudes Spatiales (of France) |
| COSMIC | Constellation Observing System for Meteorology, Ionosphere and Climate |
| CT | Canonical Transform |
| CT2 | Canonical Transform (of type 2) |
| CVS | Concurrent Version System |
| D |
| DADF | Data Acquisition and Dissemination Facility |
| DCP | Data Collection Platform |
| DD | Double Differenceing |
| DD2 | Double Differenceing (with two fiducial stations) |
| DMI | Danish Meteorological Institute |
| DMSP | Defense Meteorological Satellite Program (USA) |
| DoD | US Department of Defense |
| DOP | Detailed Operational Proposal |
| DPDD | Detailed Products Description Document |
| DRI | Delivery Readiness Inspection |
| DWD | Deutscher Wetterdienst |
| E |
| E-GVAP | European GPS Water Vapour |
| ECMWF | European Centre for Medium-Range Weather Forecasts |
| ED | Extended Development |
| EDP | Extended Development Phase |
| EGM96 | Earth Gravity Model - 1996 (Lemoine et al, 1998) |
| EGOPS | End-to-end GNSS Occultation Performance Simulator |
| ENG | Engineering |
| ENVISAT | Environmental Satellite |
| EOS Earth | Observing System |
| Ephemeris | A table showing a satellite's location over time |
| EPS | EUMETSAT Polar Satellite System |
| EPS/PP | EPS Preparatory Programme |
| EQUARS | Equatorial Atmosphere Research Satellite |
| ERS | European Remote Sensing satellite |
| ESA | European Space Agency (Paris, France) |
| ESOC | European Space Operations Centre (Darmstadt, Germany) |
| ESTEC | European Space Research and Technology Centre (Noordwijk, The Netherlands) |
| EUCOS | EUMETNET Network of European Observing System |
| EUMETCast | EUMETSAT's dissemination system |
| EUMETSAT | European Organisation for the Exploitation of Meteorological Satellites |
| EUMITS | EUMETSAT on-line Invitation to Tender System |
| EURD | End User Requirements Document |
| F |
| Fiducial | Fiducial sites are fixed GPS receivers on the ground, against
which data from the satellite can be differenced |
| FM | Forward Model |
| FSI | Full Spectrum Inversion |
| G |
| GALILEO | European GNSS constellation project (EU) |
| GCOS | Global Climate Observing System |
| GLONASS | Global Navigation Satellite System (Russia) |
| GMES | Global Monitoring for Environment and Security |
| GNSS | Global Navigation Satellite System |
| GOES | Geostationary Operational Environmental Satellite (USA) |
| GOME | Global Ozone Monitoring Experiment |
| GPAC | GNSS RO Processing and Archiving Centre (formerly GRAS Processing and Archiving Centre) |
| GPS | Global Positioning System (USA) |
| GPS POD | GPS Precise Orbit Determination products |
| GPS/MET | GPS/Meteorology Experiment on Microlab-1 (USA) |
| GPSOS | GPS Occultation Sensor |
| GPSPP | GPS Processing Package |
| GPSWV | GPS for Water Vapour |
| GRACE | Gravity Recovery and Climate Experiment |
| GRAS | GNSS Receiver for Atmospheric Sounding |
| GRAS GSN | Term used for the GRAS network of the fiducial ground stations |
| GRAS POD | GRAS Precise Orbit Determination products |
| GRAS SAF | Former name of the ROM SAF |
| GSN | Ground Support Network |
| GSN SSD | Term used for the set of data from the GSN |
| GTS | Global Telecommunication System |
| H |
| HIRLAM | High Resolution Limited Area Model |
| HIRS | High Resolution Infrared Radiation Sounder |
| HR | High Rate data (used for data taken at a rate of 50 observations per
second; these are used for measurement of the stratosphere and troposphere) |
| HRIT | High Rate Information Transmission |
| HRPT | High Rate Picture Transmission |
| I |
| IASI | Infrared Atmospheric Sounding Interferometer |
| ICD | Interface Control Document |
| IEEC | Institut d'Estudis Espacials de Catalunya |
| IGOS | Integrated Global Observation Strategy |
| IGS | International Geodynamics Service |
| IJPS | Initial Joint Polar System |
| IOP | Initial Operational Proposal |
| ISO | International Organization for Standardization |
| IU | Interaction with Users |
| J |
| JPL | Jet Propulsion Laboratory |
| JOP | Joint Operation Procedure |
| K |
| KNMI | Koninklijk Nederlands Meteorologisch Instituut |
| L |
| L1 | GPS carrier frequency, 1575.42 MHz |
| L2 | GPS carrier frequency, 1227.60 MHz |
| LEO | Low Earth Orbit |
| LEOP | Launch and Early Orbit Phase |
| LR | Low Rate data (observations taken once every ten seconds, used to
calculate the satellite's orbit) |
| LRIT | Low Rate Information Transmission |
| LRPT | Low Rate Picture Transmission |
| M |
| M&C | Management and Coordination |
| MARF | Meteorological Archive and Retrieval Facility |
| Meteosat | EUMETSAT geostationary meteorological satellite |
| MetO | United Kingdom Meteorological Office (aka Met Office) |
| Metop | Meteorological Operational Polar satellite (EUMETSAT Polar System spacecraft) |
| Metop POD | Metop Precise Orbit Determination products |
| MG | Management |
| MHS | Microwave Humidity Sounder |
| MPEF | Meteorological Products Extraction Facility (EUMETSAT) |
| MSC | Meteorological Service of Canada |
| MSG | Meteosat Second Generation |
| MTP | Meteosat Transition Programme |
| N |
| NASA | National Aeronautics and Space Administration (USA) |
| NCAR | National Center for Atmospheric Research, a division of UCAR |
| NESDIS | National Environmental Satellite Data and Information Service (of NOAA) |
| NMC/NCEP | National Meteorological Center / National Center for
Environmental Prediction |
| NMS | National Meteorological Service |
| NOAA | National Oceanic and Atmospheric Administration (USA) |
| NPOESS | National Polar-Orbiting Operational Environmental SAtellite System (NOAA) |
| NSPO | Taiwan National Space Program Office |
| NRT | Near real time |
| NWP | Numerical Weather Prediction |
| O |
| O3M SAF | Ozone SAF |
| OFL | Offline |
| OGS | Overall Ground Segment |
| OICD | Operational Interface Control Document |
| OL | Open Loop |
| OPS | Operations |
| OR | Operations Review |
| ORR | Operations Readiness Review |
| OSI SAF | Ocean & Sea-Ice SAF |
| P |
| PAC | Policy Advisory Committee (of EUMETSAT) |
| PCR | Products Consolidation Review |
| PFS | Product Format Specification (EUMETSAT) |
| PGS | Primary Ground Station |
| POD | Precise Orbit Determination |
| PP | Projects Plan |
| PPF | Product Processing Facility |
| PRN | Pseudo-Random Noise (one of 32 possible "gold codes" assigned to
each GPS satellite; the PRN number is used in this database to identify different GPS satellites) |
| PT | Project Team |
| PVR | Product Validation Report |
| Q |
| QI | Quality Indicator |
| QC | Quality Control |
| R |
| RINEX | Receiver Independent Exchange Format (a standard file format for
storing the observations of GPS receivers) |
| RMDCN | Regional Meteorological Data Communication Network |
| RMS | Root Mean Square |
| RO | Radio Occultation |
| ROM SAF | Radio Occultation Meteorology SAF (former GRAS SAF) |
| ROPP | Radio Occultation Processing Package |
| RR | Requirements Review |
| RTM | Radiative Transfer Model |
| RTTOV | Radiative Transfer model for TOVS |
| Rx | Receiver |
| S |
| S/A | Selective Availability (a mode that the GPS satellites are usually
in, which degrades the accuracy of their signal for non-military users) |
| S/C | Abbreviation for "spacecraft" |
| SAC-C | Satelite de Aplicaciones Cientificas - C |
| SAF | Satellite Application Facility (EUMETSAT) |
| SAG | Science Advisory Group |
| SAR | Synthetic Aperture Radar |
| SCI | Science |
| SCIAMACHY | Scanning Imaging Absorption Spectrometer for Atmospheric Cartography |
| SD | Single Differencing |
| SEVIRI | Spinning Enhanced Visible and Infrared Imager |
| SG | Steering Group |
| SNR | Signal to Noise Ratio |
| SP | Science Plan |
| SRD | System Requirements Document |
| SRN | System/software Release Note |
| SSD | Sounding Support Data |
| SST | Sea-surface temperature |
| State Vector | A collection of variables that can be uploaded to the
satellite to set its state |
| STG | Scientific and Technical Group (of EUMETSAT) |
| STRR | System Test Results Review |
| SVN | Identification number assigned to each GPS satellite |
| SVTRR | System Validation Test Results Review |
| T |
| TBA | To Be Added |
| TBC | To Be Confirmed |
| TBD | To Be Determined |
| TIROS | Television and Infrared Observation Satellite |
| TLA | Three Letter Acronym |
| TOA | Top of the atmosphere |
| TOUGH | Targeting Optimal Use of GPS Humidity Measurements in Meteorology |
| TOVS | TIROS Operational Vertical Sounder |
| TZD | Tropospheric (Total) Zenith Delay |
| U |
| UCAR | University Corporation for Atmospheric Research |
| U-MARF | Unified Meteorological Archive and Retrieval Facility. Former name of the EUMETSAT Data Centre. |
| UNAVCO | University Navstar Consortium |
| UR | User requirements |
| URD | User Requirements Document |
| UTC | Universal Time Coordinated (in practice the same as Greenwich Mean Time) |
| V |
| VAR | Variational analysis: 1D, 2D, 3D, or 4D variants (NWP assimilation technique) |
| VS | Visiting Scientist |
| VSA | Visiting Scientist Activity |
| W |
| WBS | Work Breakdown Structure |
| WMO | World Meteorological Organization |
| WP | Work Package |
| WV | Water vapour |
| X |
| Y |
| Z |
| ZD | Zero Differencing |
| ZTD | Zenith Tropospheric (Total) Delay |
