Geomagnetic storm of 01/12/2023
The arrival on Earth of material from three separate coronal matter ejections, but which came together in a single plasma cloud on the way from the Sun to Earth, triggered a geomagnetic storm on the morning of December 1st with planetary activity index Kp = 7. This corresponds to the third highest degree of geomagnetic activity (strong storm) consisting of five levels.
Using data from the Geophysical and Astronomical Observatory of the University of Coimbra, we have been able to follow this geomagnetic storm since it began, and we can see that it is now in the recovery phase, after 3 days (see figure). For comparison purposes, see also the Coimbra Observatory's record of the two most intense storms so far in 2023, on March 23 and April 23.
As can be seen, the December 1st storm wasn't particularly intense, but it did have its own characteristics. Compared to the March and April storms, the value of the X component of the geomagnetic field (North-South) did not drop to such low values. However, the start of the December storm (the Sudden Storm Commencement) is very well marked, better than for the other two.
Researchers from the Physics Department/CITEUC have been studying these events in order to understand how they can affect sectors of activity such as electricity transportation, through the induction of GICs (geomagnetically induced currents) in the electricity grid and in REN's substations.
