2025 Workshop: KiTS-RX-MESO-CEDAR Part 2

Substorms are one of the main processes in which Earth’s magnetosphere-ionosphere system responds to driving from the solar wind. During the substorm growth phase energy is stored in the magnetotail lobes before releasing during the expansion phase. However, the onset mechanism that triggers the explosive expansion phase is not well understood. While magnetic reconnection is known to play a role in the explosive release of energy, there may be a separate mechanism for onset (e.g. current disruption or ballooning/interchange instability). Other questions include the role of preconditioning during the growth phase that determine the properties of the pre-onset magnetotail current sheet. To complicate matters further, observations of the aurora mapped to the magnetotail can have large errors in their location.

Due to the breadth of this topic, we will have 2 joint sessions. In these sessions we hope to bring together researchers from both GEM and CEDAR communities to share their expertise on this topic. Linking dynamics between the ionosphere and magnetotail is a key part of understanding the magnetospheric system-of-systems response to solar wind driving. In this, the second session, we plan to give presentations ~10 minutes each (including questions) to explore substorm onset and continue the conversation from the first session. In these sessions, we aim to highlight the importance of satellite and ground-based observations, along with magnetospheric and ionospheric modeling, in understanding the coupled magnetosphere-ionosphere system and unraveling substorm dynamics.