Incoherent Scatter Radar Study of the F1 Region Composition, Coupling, Dynamics and Energetics

Miami University, Oxford OH

Investigators

Abstract

The ionosphere is the electrically conductive layer of the atmosphere that extends from 100 km to the edge of space. This research addresses the F1 layer of the ionosphere that spans 130-230 km. This region is populated by molecular ions at the lower levels and atomic ions at the upper boundary. This mixture of constituents has led to the F1 region being less studied than other parts of the ionosphere where the composition is simpler. However, F1 electric fields and ion drifts are highly variable in space and time, so understanding this region is clearly important for electromagnetic wave propagation, space weather prediction, and their ramifications for communications and positioning industries. Incoherent scatter radars (ISR) are the primary instruments to study the F1 layer. Radar signals ("echoes") can yield information about wind and temperature, but the process suffers from a lack of uniqueness, as different combinations of ion mass and electron/ion temperatures can present with the same echo power. The Principal Investigator (PI) will combine ion and plasma emissions observed by the ISR at Arecibo to infer temperature, composition and velocity without the traditional assumptions that have constrained previous efforts. He will examine altitude, seasonal and solar activity dependences, and the balance between photochemical and dynamical processes that maintain F1. This work contributes to our fundamental understanding of ionospheric physics, while showcasing new strategies for mining ISR measurements. The PI's efforts affirm Arecibo Observatory's reputation for scientific excellence as the facility transitions from National Science Foundation (NSF) management to its new administration by the University of Central Florida. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.