Influence of Thunderstorms on the Structure of the Ionosphere using Composite Analysis

It is well known in the amateur (ham) radio community that thunderstorms have a significant influence on local and long-distance high-frequency (HF) communications. This study aims to characterize the structure of the ionosphere in response to strong convective activity and cloud electrification. Superposed Epoch Analysis is applied to surface weather observations and ionosonde data at Eglin Air Force Base, Florida from August 2014 to July 2017. Preliminary results indicate that thunderstorms significantly modify the structure of the ionosphere, generating statistically different measurements of several key parameters (e.g., foEs, hmF2, ITEC) compared to clear-sky observations. Seasonal and diurnal influences between the thunderstorm and clear sky cases are also explored. Accurate characterization of the ionosphere in response to thunderstorms has important implications for the effective use of HF communications in civilian and military operations, to include emergency services, aviation, amateur radio, and over-the-horizon radar.