63^rd ANNUAL CONFERENCE OF THE SA INSTITUTE OF PHYSICS

Deriving thermospheric neutral density from SuperDARN radar data

26 Jun 2018, 15:00

2h

Poster Presentation Track D2 - Space Science Poster Session 1

Speaker

Ms Eva Gnegy (University of Michigan)

Description

Knowledge of thermospheric neutral density, above 200 km altitude, is important for applications such as satellite drag, which give satellite lifetime, and long-term climatic trends such as global warming. We have successfully applied theory (ion momentum equation) to incoherent scatter radar (ISR) data (e.g., EISCAT) to extract the thermospheric neutral density above 300 km. However, ISRs provide poor coverage and are expensive to operate. Hence, we now focus on coherent scatter radars, which provide great coverage and are cheap to operate. Simplification of the ion momentum equation applied to the ionosphere shows that from the rate of change in ion velocity we can derive the ion-neutral collision frequency, and from this we can calculate the neutral density if the atmosphere is a mono-species or of known composition. The SuperDARN radar global network of 35 radars covers much of the northern and southern hemisphere polar regions. Normally, the radars observe each beam at a cadence of once per minute. For this novel experiment, we operated selected radars on a single beam with a cadence of one second. This project consists of applying the theory to selected radar data sets, all of which are available. The resultant thermospheric neutral density estimate will be compared to the standard MSIS model.

Supervisor details<br><b>If not a student, type N/A.</b><br>Student abstract submision<br>requires supervisor permission:<br>please give their name,<br> institution and email address.

Michael Kosch, SANSA mkosch@sansa.org.za