| AFRL | Air Force Research Laboratory |
| AIM | atmosphere ionosphere magnetosphere |
| AIT | artificial ionospheric turbulence |
| AMISR | Advanced Modular Incoherent Scatter Radar |
| API | artificial periodic irregularity |
| APL | artificial plasma layer |
| BRIOCHE | Basic Research on Ionospheric Characteristics and Effects |
| CEDAR | Coupling, Energetics, and Dynamics of Atmospheric Regions |
| CLUSTER | European space agency mission using four identical spacecraft to probe Earth’s magnetosphere in three dimensions |
| CME | coronal mass ejection |
| CNES | Centre National d’Etudes Spatiales (space agency of France) |
| CPCP | cross-polar-cap (or transpolar) potential |
| DARPA | Defense Advanced Research Projects Agency |
| dBW | power ratio in decibels (dB) of the measured power referenced to 1 watt |
| DEMETER | Detection of Electro-Magnetic Emission Transmitted From Earthquake Regions |
| DMSP | Defense Meteorological Satellite Program |
| DOD | Department of Defense |
| DSX | (Air Force) Demonstration and Science Experiments |
| EISCAT | European Incoherent Scatter Association |
| EIW | Earth-ionosphere waveguide |
| ELF | extremely low frequency |
| EM | electromagnetic |
| EMIC | Electromagnetic Ion Cyclotron (waves) |
| ePOP | enhanced Polar Outflow Probe |
| EPSCoR | Experimental Program to Stimulate Competitive Research |
| ERC | Engineering Research Center |
| ERG | Energization and Radiation in Geospace |
| ERP | effective radiated power |
| FAI | field aligned irregularity |
| FAST | Fast Auroral Snapshot |
| GHz | gigahertz |
| GIMA | Geophysical Institute Magnetometer Array |
| GPS | Global Positioning System |
| GRACE | Gravity Recovery and Climate Experiment |
| GW | gigawatt |
| HAARP | High Frequency Active Auroral Research Program |
| HF | high frequency (radar) |
| IAR | ionospheric Alfven resonator |
| ICD | ionospheric current drive |
| IM | ionospheric modifications |
| IRI | ionospheric research instrument |
| ISR | incoherent scatter radar |
| ITM | ionosphere thermosphere magnetosphere |
| LWA | Long Wavelength Array |
| MEO | medium Earth orbit |
| MI | magnetosphere-ionosphere |
| MLT | mesosphere and lower troposphere |
| MS | magnetosonic |
| MUIR | Modular UHF Ionosphere Radar |
| NASA | National Aeronautics and Space Administration |
| NRC | National Research Council |
| NRL | Naval Research Laboratory |
| NSF | National Science Foundation |
| O&M | Operations and Maintenance |
| PFISR | Poker Flat Incoherent Scatter Radar ISR (silent P) |
| PI | principal investigator |
| PMC | polar mesospheric cloud |
| PMSE | polar mesosphere summer echo |
| RAX | Radio Aurora Explorer |
| Resonance | Russian-led mission using four similar spacecraft to measure plasma parameters of the Earth’s inner magnetosphere. |
| RF | radio frequency |
| RIA | radio-induced aurora |
| RISR | Resolute Bay Incoherent Scatter Radar |
| ROM | rough order of magnitude |
| SAID | subauroral ion drift |
| SAPS | subauroral polarization stream |
| SAW/SA | shear Alfvén wave |
| SBIR | Small Business Innovation Research |
| SEE | stimulated electromagnetic emission |
| SPEAR | Space Plasma Exploration by Active Radar |
| SRI | Stanford Research Institute International |
| STC | Science and Technology Center |
| SuperDARN | Super Dual Auroral Radar Network |
| SWMI | solar wind-magnetosphere-ionosphere |
| TARANIS | Tool for the Analysis of Radiations from Lightnings and Sprites |
| TEC | total electron content |
| THEMIS | Time History of Events and Macroscale Interactions during Substorms |
| UHF | ultrahigh frequency |
| ULF | ultralow frequency |
| VHF | very high frequency |
| VIPIR | Versatile Interferometric Pulsed Ionospheric Radar |
| VLA | Very Large Array |
| VLF | very low frequency |
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