Convection and Substorms

Kyle Murphy, 24 August 2020

Dr. Christine Gabrielse gave an extraordinarily comprehensive overview of convection and substorms and how the two phenomena fit into both past and future seminars in this lecture series. Christine’s seminar focused on providing a broad but thorough overview of convection and substorms. She began with a discussion of the Dungey cycle and the link to large scale convection and magnetic flux transport in the coupled solar wind-magnetosphere system. Christine then expanded on the details of large-scale convection in the magnetosphere and its link to the ionosphere and convection cells (as observed by ground-based radars) in magnetosphere-ionosphere (MI) coupling. She continued her overview of the large-scale dynamics of convection with a description of particle motion in the magnetosphere and how the superposition of ExB drift (due to the convection and corotational electric fields) and gradient curvature drift (a result of the non-uniform magnetospheric electric field) lead to large scale motion of plasma in the magnetosphere. Christine followed this up by moving to smaller scales and discussing mesoscale convection, the transport of flux and plasma by transient processes which can account for a significant portion of the overall convection of magnetic flux and plasma in the magnetosphere. She further discussed how mesoscale convection occurs in both the day and night side magnetosphere and provided an overview of a number of processes responsible for mesoscale convection including bursty bulk flows and flux transfer events. Following mesoscale convection Christine provided a detailed overview of substorms including: the substorm growth, expansion, and recovery phases; the substorm timing dilemma; dipolarizations, flow channels, and magnetic flux pileup; the substorm current wedge; and substorm aurora. Christine completed her overview with a discussion of convection and ionospheric feedback, MI coupling, and plasma and particle transport. In her final slide Christine discussed recent work at GEM on mesoscale convection and the role of convection in radiation belt dynamics, advances in magnetospheric modeling, as well as a look to the future and importance of multi-point missions to further our understanding of convection and substorms.

You can watch Christine’s seminar on our YouTube channel and you can find a copy of her talk (with a number of references for further reading) here.

Aditional Reserouces

  1. GEM Focus Group on Magnetotail Dipolarization and its Effects in the Inner Magnetosphere
  2. GEM FG 3D Ionospheric Electrodynamics and Its Impact on the Magnetosphere-Ionosphere-Thermosphere Coupled System
  3. GEM FG System Understanding of Radiation Belt Particle Dynamics through Multi-spacecraft and Ground-based Observations and Modeling