Investigation of nonlinearity effect during storm time disturbance

We examine the nonlinearity effect in the Disturbed Storm Time (Dst) signals during minor, moderate and major geomagnetic storm between the year 2008 and 2016 using Recurrence Plot (RP), Recurrence Rate (RR) and Approximate Entropy (ApEn). The dynamics of the Dst signals behave in stochastic path during the minor geomagnetic stormy period and in deterministic path during increasing geomagnetic stormy period. As the geomagnetic storm increases, the RP showed more deterministic structure indicating that it possesses the potential to detect geomagnetic storm event even at the infinitesimal impact of the geomagnetic storm. The dynamical behaviour is reflected in the RR as the geomagnetic storm intensifies. The occurrence of geomagnetic storm associated with significant Dst signal and monthly average RR is prevalent during the beginning year (2012) of the high solar activity than the peak year (2014) of the high solar activity. Our results show that higher average RR is not consistent throughout the equinoctial season between the year 2008 and 2016.