From the Sun to the Earth: August 25, 2018 geomagnetic storm effects

Abstract

Abstract. On August 25, 2018 the interplanetary counterpart of the August 20, 2018 Coronal Mass Ejection (CME) hit the Earth, giving rise to a strong G3 geomagnetic storm. We present a description of the whole sequence of events from the Sun to the ground as well as a detailed analysis of the observed effects on the Earth's environment by using a multi instrumental approach. We studied the ICME propagation in the interplanetary space up to the analysis of its effects in the magnetosphere, ionosphere and at ground. To accomplish this task, we used ground and space collected data, including data from CSES (China Seismo Electric Satellite), launched on February 11, 2018. We found a direct connection between the ICME impact point onto the magnetopause and the pattern of the Earth's polar electrojects. Using the Tsyganenko TS04 model prevision, we were able to correctly identify the principal magnetospheric current system activating during the different phases of the geomagnetic storm. Moreover, we analyzed the space-weather effects associated with the August 25, 2018 solar event in terms of evaluation geomagnetically induced currents (GIC) and identification of possible GPS loss of lock. We found that, despite the strong geomagnetic storm, no loss of lock has been detected. On the contrary, the GIC hazard was found to be potentially more dangerous than other past, more powerful solar events, such as the St. Patrick geomagnetic storm, especially at latitudes higher than 60° in the European sector.

A mathematical model of lithosphere–atmosphere coupling for seismic events

“…The first detection of changes in ionospheric parameters (e.g., F region critical frequency—foF2) associated to the Alaskan earthquake was reported in 1 . In general, it is well known that the ionosphere is influenced from above by the solar activity, leading to the so-called solar wind-magnetosphere-ionosphere coupling 2 – 5 . On the other hand, the ionospheric medium can be influenced from below by atmospheric waves generated in the neutral atmosphere 6 .…”

Ionospheric Response Over Brazil to the August 2018 Geomagnetic Storm as Probed by CSES‐01 and Swarm Satellites and by Local Ground‐Based Observations

“…As already noticed by Astafyeva et al. (2020), the CME structure arrived on the Earth at 02:45 UT on 25 August without providing the classical signature of a Sudden Storm Commencement on the SYMH (see also Piersanti et al., 2020, for details), that during the day reveals rather the signature of the magnetospheric compression due to the increased P sw . This effect can also be seen in the correspondence among the three P sw peaks (at about 08:30, 11:00, and 13:20 UT) during 25 August and the peaks of SYMH right before the main phase of the storm.…”

“…These also trigger the oscillations found in J h , with a similar impact on both hemispheres. During this period, the SYMH time profile shows substorm‐like signatures that have been hypothesized to be driven by the effect of a corotating interaction tegion (CIR) (Piersanti et al., 2020], and the most significant variations of the EEF linked to the PPEF take place. The recovery phase of the storm is featured by SW speed higher than about 400 km/s and oscillations of IEF/ B z that correspond to meaningful oscillations in the heating activity, quite symmetrically on the polar caps of both hemispheres: indeed, CIR‐driven geomagnetic storms are able to induce relativistic particle acceleration, enhanced magnetospheric convection and ionospheric heating (Pokhotelev et al., 2009).…”

“…(2019) and by Piersanti et al. (2020). This is, to date, the most intense storm that occurred during the lifetime of the CSES‐01 satellite (Shen et al., 2018), launched in February 2018.…”

Geoeffective space weather events signatures in cosmic rays during the ascending phase of the solar cycle 24

“…They also provide a detailed measure of the intensity of the physical reasons [3]. One of the space weather impact aspects, namely, on electrical networks, was extensively studied not only in North America [4,5] and Scandinavia [6][7][8], but also in Europe: in United Kingdom [9], Spain [10], Greece [11], Italy [12,13], Austria [14], the Czech Republic [15,16], and finally, by us, in Poland [17][18][19][20].…”