Preface to the Special Section on Substorm Research

Abstract

During the week of 16–20 October 2023, the 15th International Conference on Substorms (ICS-15) was held in the city of Deqing, on the scenic foothill of Mount Mogan in Zhejiang, China. Nearly 100 scientists around the world participated in the meeting, either in-person or online. The conference featured 59 oral presentations, including four 50-min tutorial lectures, and 14 poster presentations. Following the convention of the ICS conference series, participants were invited to submit their studies to a special collection of papers. Submissions from the broader space physics community, even if not participating in the conference, were also encouraged. All the articles in the special collection have undergone a rigorous peer-review process before their publication in either Journal of Geophysical Research Space Physics or Geophysical Research Letters.

This collection, like the conference itself, covers a wide spectrum of topics related to substorm dynamics. There are articles discussing the enduring question of substorm event sequence and triggering mechanisms, which also involve the identification of substorms from various aspects. The roles of meso-scale flows and associated electromagnetic structures in the substorm dynamics constitute another topic of broad interest, which also contributes to the coupling between magnetotail and ionosphere/thermosphere. Another interesting topic is the consequence of substorm injections in the inner magnetosphere, including the excitation of plasma waves and the acceleration of radiation belt electrons. Finally, there are a few articles focusing on geomagnetic storms and their relationship with substorms, and a few articles on subauroral physics related to STEVE (Strong Thermal Emission Velocity Enhancement).

While it is still challenging to reach a consensus on every aspect of substorm research, we believe that the advancements in observational capabilities have provided unprecedented opportunities for us to study the substorm-associated phenomena across multiple scales. Many studies in this collection utilize data from multiple sources, from in-situ spacecraft observations to ground-based auroral imagers, magnetometers and radar networks, to refine current models and improve our understanding of the nature of substorms.

Finally, we would like to thank the conference organizers, the Chinese Society of Space Research and Peking University, for their support to make the ICS-15 meeting possible. We are also grateful to all the meeting attendees for their contributions and lively discussions throughout the meeting, and to the AGU editors, editorial staffs, reviewers and authors who made this collection a reality.