2017/10/21 by Denny M. Oliveira, E. Zesta, Oliveira, D. M. +7 · 1 citation
Biochemistry, Genetics and Molecular Biology · Earth and Planetary Sciences · Physics and Astronomy · #FOS: Physical sciences #Geomagnetism and Paleomagnetism Studies #Geophysics and Gravity Measurements #Ionosphere and magnetosphere dynamics #Space Physics (physics.space-ph)
paper · pdf · doi:10.48550/arxiv.1710.07743
openalex publication_date 2017/10/21 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
In this study, we investigate thermospheric neutral mass density heating associated with 168 CME-driven geomagnetic storms in the period of May 2001 to September 2011. We use neutral density measured by two low-Earth orbit satellites: CHAMP and GRACE. For each storm, we superpose geomagnetic and density data for the time when the IMF Bz component turns sharply southward chosen as the zero epoch time. This indicates the storm main phase onset. We find that the average SYM-H index reaches the minimum of -42 nT near 12 hours after storm main phase onset. The Joule heating is enhanced by approximately 200% in comparison to quiet values. In respect to thermosphere density, on average, high latitude regions (auroral zones and polar caps) of both hemispheres are highly heated in the first 1.5 hour of the storm. The equatorial response is presumably associated with direct equator-ward propagation of TADs (traveling atmospheric disturbances). A slight north-south asymmetry in thermosphere heating is found and is most likely due to a positive By component in the first hours of the storm main phase.