Geomagnetic storm (GMs) is a significant unsettling influence of Earth’s magnetosphere that happens when there is an extremely productive trade of energy from the solar wind into the space climate encompassing Earth. Storms result from variations in the solar wind that produces significant changes in the flows, plasmas, and fields in Earth’s magnetosphere. A southward directed solar wind magnetic field at the dayside of the magnetosphere is responsible to create GMs, large GMs are associated with coronal mass ejections (CMEs) also. In this work we take the GMs of magnitude ≤ -100 nT and CMEs having velocity more than 1000 km/s from 2010-2020. During this time span we have noted 28 geomagnetic storms (GMs). To analyze the GMs with other solar activities (Flares & CMEs) conducted a statistical analysis of the data of the Dst (disturbance storm time) index of Geomagnetic storms and Solar flare flux and CMEs. We found the low positive correlation between Dst index and the solar flare flux with correlation coefficient 0.21. We also found a correlation between the Dst index with different classes of flares (X and M), there is a strong positive correlation between Dst index and X class solar flare having coefficient 0.97, further the correlation of Dst index and M class flare is very low with correlation coefficient 0.04. We found that the CMEs are negatively correlated with Dst index with correlation -0.09. The present result implies that the geomagnetic storms formation dependent on the flares particularly x class but does not on the CMEs during the time taken.
Keywords: – Coronal mass ejections, Solar flares, Space weather, Geomagnetic Storm, Dst Index.
Lavi Kumar Vaswani1*, Preetam Singh Gour2, Ashish Kumar Meena3, Shiva Soni4