- This paper presents a statistical analysis of different parameters responsible for the geoeffectiveness of solar eruptions during the rising phase of solar cycle 24. 33 halo events are selected from the beginning of the current solar cycle (2009-2013). The levels of geomagnetic activity are categorized into two groups based on the observed minimum Dst index, i.e., moderate (-100 nT < Dst ≤ -50 nT) and intense (Dst ≤ -100nT). We have plotted graphs between the parameters and correlation coefficient is obtained. The correlation coefficient between Dst index and CME speed is 0.12 and between Dst index and X-ray flux of flares is 0.25, which shows that high speed CME and big flares are not the only parameters for geoeffectiveness. Eventually, the correlation between CME speed and X-ray flux is better, i.e., 0.40, which implies that big flares produce high speed CME and hence strong Dst indexes. |