| Abbreviation | Definition |
|---|---|
| I | Ice |
| IAAM | Integrated Advacned Aviation Meteorological |
| IABM | International Association of Broadcast Meteorology |
| IAMS | Initial Attack Management System |
| IAP | International Arctic Project |
| IB | Inverted Barometer |
| IC | Intra-Cloud |
| ICAM | International Conference on Alpine Meteorology |
| ICAO | International Civil Aviation Organization |
| ICCP | International Commission on Clouds and Precipitation |
| ICEO | IEEE Committee on Earth Observation |
| ICMO | International Conference on Meteorology Observations |
| ICMSSR | Interdepartmental Committee for Meteorological Services and Supporting Research |
| ICSU | International Council of Scientific Unions |
| ICWG-CC | Inter Center Working Group on Climate Change |
| IDCZ | Increased Droplet Concentration Zone |
| IDF | Intensity, Duration, Frequency |
| IDF | Intensity-Duration-Frequency |
| IDGIS | Interactive Distributed Geographical Information System |
| IEW | Intelligence and Electronic Warfare |