Collaborative Research: Comprehensive Investigation of Midlatitude Ionospheric Irregularities

Clemson University, Clemson SC

Investigators

Abstract

This project will address fundamental science questions on how the midlatitude ionosphere behaves as a system. The midlatitude ionosphere is as prone to instability as the equatorial and auroral ionospheres despite the lack of obvious sources of free energy, and there is no comprehensive theory to explain this. There is a clear relationship between neutral winds, wind shear, and turbulence and Es layer formation and structuring, but the causal links have yet to be clearly articulated. Equally clear is that E region irregularities and F region medium-scale traveling ionospheric disturbances (MSTIDs) and irregularities are electrically coupled, but the roles of the regions (sources, loads, coupled resonators) remain unspecified. This project will investigate midlatitude sporadic E layers, MSTIDs, the associated plasma density irregularities, their mutual coupling, their geomagnetic conjugacy, and coupling to the thermospheric neutral motion. The investigation will have experimental, theoretical, and modeling aspects. The experimental component of the research will be conducted in the Caribbean and will center on the Arecibo incoherent scatter radar. This radar will be supported by a coherent scatter radar imager fielded so as to have common E- and F-region scattering volumes with Arecibo. The project will also utilize the Arecibo lidars and all-sky imagers as well as sounders and GPS Total Electron Content (TEC) data. The theoretical investigation will focus on the turbulence properties of the neutral motions in the mesosphere/lower thermosphere (MLT) region, which will be studied using a multi-scale analysis, and on the consequences for ionospheric structuring. Modeling work will incorporate a newly developed, fully three-dimensional plasma dynamics model. Undergraduate and graduate students will participate in this work, and public outreach activities will be carried out in the Caribbean.