CEDAR Postdoc: Coupled Ionosphere/Thermosphere/Exosphere/Plasmasphere Neutral Density Measurement Initiative

University Of Illinois At Urbana-Champaign, Urbana IL

Investigators

Abstract

Quantification of neutral species densities in the upper thermosphere and lower exosphere remains elusive in spite of recent advances in both theoretical modeling and observations. Techniques for routinely measuring neutral atmosphere parameters using ground-based instruments is essential if progress is to be made. This award takes advantage of precise new measurement capabilities to attack the problem of atomic oxygen and hydrogen density quantification in the region of low-earth orbit. The study will make use of measurements of light ion species densities and ion temperatures in the F-region through the topside ionosphere that are currently being made at the Arecibo and Millstone Hill Observatories. The radar observations are combined with sensitive optical airglow measurements, and neutral densities are extracted using ion-energy balance, charge exchange equilibrium, and the coupled moments of the Boltzmann equation. The methodology uses existing radar chain data and new measurements from clustered instrumentation at Arecibo. The study will lead to a self-consistent technique to derive neutral densities routinely and reliably at and above the F-region peak through ground based remote sensing of the coupled atmospheric regions. In addition to evaluating and constraining contemporary atmospheric models and theories, the proposed activity will further address broad concerns of the scientific community by allowing for the important characterization of the neutral atmosphere with respect to secular, temporal, seasonal, and solar cycle variations.