| Acronym | Meaning |
| TCAS-II | Traffic Alert And Collision Avoidance System |
| TCCR | Technical Committee For Computing Resources |
| TCI | Tropical Cyclone Initiation |
| TCIPO | TOGA/COARE International Project Office |
| TCMRS | Tropical Climate Monitoring And Research Station |
| TCP | Technology Commercialization Program |
| TCP | Transport Control Protocol |
| TCP/IP | Transmission Control Program/Internet Protocol |
| TCS | Thermal Control System |
| TCSM | Tropospheric Chemistry Systems Models |
| TCZ | Tropical Cloud Zone |
| TCZ | Tropical Convergence Zone |
| TD | Thermal Dissociation |
| TDCIMS | Thermal Desorption Chemical Ionization Mass Spectrometer |
| TDF | Technology Development Facility |
| TDL | Techniques Development Lab |
| TDL | Tunable Diode Laser |
| TDLAS | Tunable Diode Laser Absorption Spectroscopy |
| TDM | Three-dimensional Time-varying Mesoscale Model |
| TDM | Time Division Multiplex |
| TDMC | TAMEX Data Management Center |
| TDR | Tracking And Data Relay |
| TDWR | Terminal Doppler Weather Radar |
| TEA | Transversely Excited Atmospheric (pressure) |
| TEB | Tropical Experiment Board |
| TEC | Tropical Experiment Council |
| TECAMS | Technical Conference On Automated Meteorological Systems |
| TECC | Tropospheric Effects Of Cloud Chemistry Program |
| TECOM | Test And Evaluation Command |
| TELNET | TCP/IP Network |
| TERAFLOPS | Trillions Of Arithmetic Operations Per Second |
| TES | Transequatorial Scatter |
| TES | Tropospheric Emission Spectrometer |
| TEXEX | Texas Frontal Experiment |
| TEXMEX | Tropical Experiment Over Mexico |
| TGB | Trace Gas Biogeochemistry Section |
| TGCM | Thermospheric General Circulation Model |
| TGS | Text And Graphics System |
| THC | Total Hydrocarbons |
| THEMIS | N/A |
| THERMEX | Thermal Wave Experiment |
| THIR | Temperature And Humidity Infrared Radiometer |
| THORPEX | The Observing System Research And Predictability Experiment |
| THREDDS | Thematic Real-time Environmental Distributed Data Services |
| TIAA | Teachers Insurance And Annuity Association |
| TIBEX | Tidewater Bermuda Experiment |
| TID | Traveling Ionospheric Disturbance |
| TIDI | TIMED Doppler Interferometer |
| TIE | The Institute Of Ecology |
| TIE-GCM | Thermosphere/Ionosphere/Electrodynamics General Circulation Model |