| Acronym | Meaning |
| FUN | FL-4 Uniform Network Project |
| FWHM | Full Width |
| FWPCA | Federal Water Pollution Control Act |
| FWQC | Federal Water Quality Criteria |
| FWS | Filter Wedge Spectrometer |
| FWS | Fish And Wildlife Service |
| FX | FSL's X-window Workstation |
| FX-ALPHA | FSL X-window AWIPS-Like Prototype For Hydrometeorological Applications |
| FY | Fiscal Year |
| G&A | General And Administrative |
| G- IV | Gulfstream IV |
| G-M | Gent-McWilliams Parameterization Scheme |
| G-TUF | G-Tunnel Underground Facility |
| G/T | Activity Per Ton |
| GA | Billion Years Unit |
| GAARS | Global Atmospheric Aerosol And Radiation Study |
| GAAS | Gallium Arsenide |
| GAC | Global Atmospheric Chemistry |
| GAC | Global Area Coverage |
| GADMAP | GATE Aircraft Data Management Program |
| GAGE | Global Atmospheric Gases Experiment |
| GAGE | Gulf-Stream Atmospheric Gradient Exchange |
| GAIM | Global Analysis |
| GAINS | Global Air-ocean IN-situ System |
| GAL | Galileo |
| GALA | Geoscience Airborne Laser Altimeter |
| GALE | Genesis Of Atlantic Lows Experiment |
| GAMETAG | Global Atmospheric Measurements Experiment On Tropospheric Aerosols And Gases |
| GAMIT | Not An Acronym |
| GAMP | Global Atmospheric Measurements Program |
| GAO | General Accounting Office |
| GAP | GATE Advisory Panel |
| GAP | GATE Advisory Panel |
| GAPEX | Ground-based Atmospheric Profiling Experiment |
| GAPS | Billions (109) Of Actions Per Second |
| GARDIAN | GBL Point Defense System |
| GARP | Global Atmospheric Research Program |
| GARP | GEMPAK Analysis And Rendering Program |
| GARP | Global Atmospheric Research Program |
| GAT | General Aviation Transponder |
| GATE | Global Atmospheric Research Programme Atlantic Tropical Experiment |
| GATT | General Agreement On Tariffs And Trade |
| GAU | General Accounting Unit |
| GAW | Global Atmospheric Watch |
| GB | Gigabyte |
| GB | Gigabits |
| GBDS | GARP Basic Data Set |
| GBPS | Gigabity (109) Per Second |
| GBYTE | Gigabyte (109) |
| GC | Gas Chromatograph |