Assessment of the Severe Geomagnetic Storm on May 10-11, 2024 Effects on the Geomagnetic Field and Ionosphere Over the Indonesian Region

Abstract

The severe geomagnetic storm on May 11, 2024, is the largest space weather phenomenon in the 25th solar cycle. This paper presents the impact of that severe geomagnetic storm (Dst =-412 nT) on the geomagnetic field and ionosphere over Indonesia. Additionally, it examines geoelectric disturbances generated during the storm and disruptions to HF radio communication in Indonesia. The study uses geomagnetic field data (HDZ) and ionospheric data (foF2) from Pontianak and Kupang, averaged minutely and hourly. The results indicate that the geomagnetic storm on May 11th, 2024 caused geomagnetic disturbances with ΔH =-471 nT in Pontianak and ΔH =-462 nT in Kupang. These disturbances led to significant geoelectric disturbances around the region with possible induced currents. In the ionosphere, the geomagnetic storm caused negative ionospheric storms during the main phase and positive storms during the recovery phase, as observed in the foF2 data from both stations. These ionospheric storms resulted in foF2 disturbances (ϕ) with values ranging from-30% to 30%, lasting for 180 minutes.