Characteristics of Medium-Scale F-region Plasma Irregularities at Equatorial and Mid Latitudes, as Observed by COSMIC Radio Occultation Receivers

Medium-scale ionospheric plasma irregularities are a persistent global feature of the earth's F-region ionosphere. Constellation Observing System for Meteorology, Ionosphere, and Climate (COSMIC) radio occultation (RO) measurements are well suited to address the incomplete global observational picture of irregularities, including their structure in the vertical dimension. A climatological database of ionospheric irregularities and their characteristics (e.g. magnitude, scale size, gradient, and associated scintillation) has been developed through detection of total electron content (TEC) perturbations by COSMIC precise orbit determination (POD) antennas and associated receivers of the Global Positioning System (GPS). Vertical scale sizes ranging from ∼2 to 50 km were resolved from 1 Hz TEC measurements. The irregularity database will be developed into a climatological data product available to the scientific community, which will describe the global or regional occurrence and characteristics of irregularities based on user input. This paper highlights results of the initial climatological study at equatorial to mid latitudes, as well as the potential applications of the forthcoming data product. The irregularity climatology provides insight into the source and generation mechanisms of irregularities observed at particular local times and geographical regions.