# Correlation Study of Auroral Currents with External Parameters During 10-12 October 2024 Superstorm
## 5 Conclusions  
This study investigated the correlation between FACs, PEJs, solar wind/IMF, and Dst parameters during the intense geomagnetic storm from 10 to 12 October 2024. The timing of FACs/PEJs reaching their peak values and lowest latitudes varied across local times and hemispheres. Correlation analysis identified the dominant external parameters influencing FACs and PEJs, revealing clear differences compared to the May 2024 storm. This suggests that the patterns of external factors affecting the peak density and minimum latitude of FACs and PEJs are event-dependent. Moreover, by comparing the October 2024 storm with the May 2024 storm, which occurred in opposite seasons in the two hemispheres, this study confirms that the hemispheric variations were primarily driven by seasonal differences in ionospheric conductivity. The following key findings are summarized:  
1. Em demonstrated the strongest correlation with FAC peak densities across multiple regions, including the northern dawnside, the southern duskside (for upward FACs), and the nightside of both hemispheres. Meanwhile, Pd exhibited the strongest correlation with FAC peak densities on the northern duskside, the northern dayside (in conjunction with Nsw for upward FACs), the southern dawnside (in conjunction with Vsw for downward FACs), and the southern dayside. Additionally, the peak downward FACs on the southern duskside exhibited the largest correlation with Dst. 2. Em exhibited the strongest correlation with peak PEJs at the northern dawn-dusk sectors and during both the northern and southern nighttime. In the Southern Hemisphere's dusk and dawn sectors, the PEJ peak was most strongly correlated with Nsw and Dst, respectively. At daytime, the northern PEJ peak correlated most strongly with Vsw, whereas in the Southern Hemisphere, it was most strongly correlated with Pd. 3. The latitudes of peak FACs at dawn-dusk and the northern nightside exhibited the strongest correlation with Em. Pd showed the highest correlation for northern daytime FACs and southern daytime upward FACs. On the southern dayside, downward FACs were most strongly correlated with IMF Bz, while on the southern nightside, upward FACs correlated best with Dst and downward FACs with Vsw. 4. The northern PEJ MLat was most strongly correlated with Pd at dawn-dusk and the nightside (together with Vsw) and with Dst on the dayside. In the Southern Hemisphere, the PEJ latitude correlated most strongly with Dst in the dawn-dusk sectors, with IMF Bz on the dayside, and with Em on the nightside. R1 and R2 FACs, as well as PEJs, were generally more intense on the dawnside than on the duskside, except for the winter R1 FACs. In both hemispheres, downward FAC density was typically higher in the daytime compared to the night. In the summer hemisphere, the daytime PEJ density exceeded that of the nighttime. Conversely, the upward FAC density on the nightside was stronger than that on the dayside, with the PEJ densities being more similar during daytime and nighttime in the winter hemisphere. Overall, FACs in the summer hemisphere were stronger than those in the winter hemisphere. 6. FACs and PEJs shifted more equatorward at dusk than those at dawn and at nighttime than at daytime. In general, FACs and PEJs were positioned at higher latitudes in the summer hemisphere than in the winter hemisphere, consistent with the results from the May 2024 storm. Given that this study focused on a single intense geomagnetic storm, extending the analysis to a series of events across different solar cycle phases could provide more generalized insights into the behavior of FACs and PEJs under different geomagnetic conditions. Conceptualization, H.W. ; methodology, H.W. ; investigation, X.X., X.H. and K.Z. ; writing--original draft preparation, H.W. ; writing--review and editing, H.W. ; visualization, X.X. and X.H. ; funding acquisition, H.W. All authors have read and agreed to the published version of the manuscript. The authors greatly appreciate the web availability of data.