Swarm+ Coupling High-Low Atmosphere Interactions: Ion Outflow

The Swarm+ Coupling: High-Low Atmosphere Interactions ITT Statement of Work (SoW) has highlighted the “compelling scientific problem” of “the least-understood causes of planetary winds,” namely planetary outflows induced by “non-thermal (e.g., frictional heating, particle precipitation, wave-particle acceleration) processes.”

The Swarm+ Coupling High-Low Atmosphere Interactions: Ion Outflow (“Swarm+ Outflow”) project, which began in May 2019, centers on using Swarm spacecraft to tackle unanswered questions around non-thermal processes that lead to ion outflow. The project approach is as follows:

• (i) Determine the conditions (eg., local time, solar wind/interplanetary magnetic field, hemisphere, season) under which 50-Hz magnetic field measurements and electron and ion density, temperature, and flow measurements made by Swarm spacecraft may be applicable for the study of energetic ion outflows;
• (ii) Determine possible statistical relationships between magnetic field perturbations measured by Swarm magnetometers and ion upflows/outflows measured at altitudes above, near, and below those of Swarm spacecraft;
• (iii) Validate and generalize previously published (e.g., Strangeway et al., 2005; Brambles et al., 2011) empirical relationships between electromagnetic perturbations and ion upflows in the Northern Hemisphere cusp region;
• (iv) Pending positive statistical results, produce a roadmap for development and refining of a Swarm-based ionospheric outflow product.

This approach involves combining Swarm plasma and field measurements with measurements from a host of other instruments, including European Incoherent SCATter (EISCAT) radars, the Cluster satellites, and University of Oslo all-sky camera measurements.