Comparative Analysis of dB/dt Response Towards dH/dt as Proxies for Geomagnetically Induced Currents (GICs) in Low-Latitude Region

Geomagnetic storms impact communication technology by disturbing the ionosphere, affecting GPS signal propagation, and causing navigation errors. These storms also induce voltages in long conductors such as communication cables, power lines, and pipelines through geomagnetically induced currents (GICs), leading to potential disruptions. This study addresses the gap in understanding geomagnetic field variations in low-latitudes, where infrastructure is less equipped for GIC disruptions. Furthermore, limitations in the availability of magnetic field components often necessitate the use of dB/dt as a GIC proxy for this region. This study aims to assess the relationship between the rate of change of the total magnetic field (dB/dt) and the horizontal magnetic field component (dH/dt) across different latitudes during the geomagnetic storm of 22–23 June 2015. Utilizing data from high (Narsarsuaq, Greenland), mid (Boulder, USA), and low (Alibag, India) latitude stations through correlation, cross-correlation, and linear regression analyses. The results reveal significant latitude dependent differences with strong correlations at mid and low latitudes. A strong linear correlation between dB/dt and dH/dt was observed, particularly at mid and low-latitudes. Cross-correlation analysis reveals synchronous responses at zero lag, indicating highly predictable relationships at lower latitude regions. Regression analysis demonstrates greater predictability of dB/dt and dH/dt at lower latitudes than at higher latitudes. These findings indicate that dB/dt is an effective proxy for GIC studies in low-latitude regions and enhance our understanding of geomagnetic impacts on infrastructure and highlight the importance of developing strategies tailored to different latitudes. This research contributes to the field by providing new insights into the use of dB/dt as a reliable measure for assessing GIC risks in low-latitude regions.