EGU26-1411, updated on 13 Mar 2026
https://doi.org/10.5194/egusphere-egu26-1411
EGU General Assembly 2026
© Author(s) 2026. This work is distributed under
the Creative Commons Attribution 4.0 License.
Oral | Wednesday, 06 May, 14:20–14:30 (CEST)
 
Room 1.85/86
Superstorm, Supersubstorms, and Joule Heating during the May 2024 event: interplanetary triggers, energy budget, and mechanisms
Rajkumar Hajra1, Bruce Tsurutani2, Quanming Lu1, Aimin Du3, Gurbax Lakhina4, and Yasuhito Narita5
Rajkumar Hajra et al.
  • 1University of Science and Technology of China, School of Earth and Space Sciences, Hefei, China (rhajra@ustc.edu.cn)
  • 2Retired, Pasadena, California 91208, USA
  • 3College of Earth and Planetary Sciences, Chinese Academy of Sciences, Beijing 100049, China
  • 4Retired, Navi Mumbai 400703, India
  • 5Institut für Theoretische Physik, Technische Universität Braunschweig, Braunschweig, Germany

The May 2024 superstorm (SYM-H peak = –518 nT) was characterized by a three-step main phase, a long and strong recovery phase, and six isolated supersubstorms (SSSs; SML < –2500 nT). We will show that the SSSs were triggered by a strong solar wind driving of ~1017 J. All six SSS events could be explained by both precursor energy and direct driving. The SSS events were unique with highly varied morphology, ranging from an isolated substorm morphology to a storm convection bay scenario. We suggest a two-mode nightside convection electric field to explain the nightside Joule heating variability, and three possible mechanisms for the dayside Joule heating.

References

  • Hajra, R., B. T. Tsurutani, G. S. Lakhina, Q. Lu, and A. Du (2024), Interplanetary Causes and Impacts of the 2024 May Superstorm on the Geosphere: An Overview, J. 974, 264 https://doi.org/10.3847/1538-4357/ad7462
  • Hajra, R., B. T. Tsurutani, Q. Lu, A. Du, and G. S. Lakhina (2025), Supersubstorms during the May 2024 superstorm, Space Weather Space Clim. 15, 51 https://doi.org/10.1051/swsc/2025047

How to cite: Hajra, R., Tsurutani, B., Lu, Q., Du, A., Lakhina, G., and Narita, Y.: Superstorm, Supersubstorms, and Joule Heating during the May 2024 event: interplanetary triggers, energy budget, and mechanisms, EGU General Assembly 2026, Vienna, Austria, 3–8 May 2026, EGU26-1411, https://doi.org/10.5194/egusphere-egu26-1411, 2026.