Multiple-band electric field responding to the geomagnetic storm on 4
November 2021
Abstract
In this paper, based on the electric field data (EFD) of the China
Seismo-Electromagnetic Satellite (CSES), which is divided into 4
frequency bands (ULF, ELF, VLF, HF) from DC to 3.5 MHz, we study the
impact characteristics of the 4 November 2021 magnetic storm activity in
different frequency bands. It was found that the electric field
anomalies caused by magnetic storms were mainly concentrated below 18
kHz, and above 18 kHz the effects were weak and gradually diminished to
negligible. In the ULF band, excluding the influence of Schumann waves,
the electric field anomalies caused by magnetic storms are mainly below
5 Hz, with the most influential frequency point being 3.4 Hz. In the ELF
band, the more obvious anomalies appear at 300 Hz – 900 Hz and above
1.8 kHz, with the most significant anomalies in the 300 Hz – 900 Hz
band around 780 Hz. In the VLF band, electric field anomalies are
concentrated in 2.5 - 10 kHz. Magnetic storms had essentially no effect
on the HF band. Magnetic storms at low and middle latitudes have a weak
effect on the ELF and VLF bands and are more pronounced in the ULF band.
During the main phase of the magnetic storm, the absolute magnitude of
variance change in the ELF and VLF bands is greater than that in the ULF
band as a whole, but the relative magnitude of variance change in the
ULF band is 10% greater than that in the ELF and VLF bands.