Abstract Details


Name: DEVI R NAIR
Affiliation: University of Kerala
Conference ID: TVS202510206
Title: Katz Fractal analysis of solar and geomagnetic indices during Mother’s Day storm of May 2024
Authors and Co-Authors: Prince P R
Abstract Type: Contributory Presentation
Abstract: The superstorm of 10-13th May 2024 (Mother’s Day storm, with peak SYM-H -518 nT, Kp=9), was triggered by preceding multiple intense CMEs and X and M class flares from solar active regions AR3664 and CR2284.Katz fractal dimension (KFD) of solar wind velocity (SWV),SYM-H and IMFBz (60 min intervals)reveals the dynamics of the geomagnetic storm and its complex nature in response to severe SW conditions. The SWV KFD ranged between 1.08-1.82 (average 1.41). KFD peaks>1.75 indicates periods of irregular or turbulent solar wind, associated with strong driving of geomagnetic storms. Recurring peaks and jumps here reflect the solar wind’s intrinsic complexity during storm periods. During the initial and towards the end of the recovery phase of the storm, KFD of SYMH approaches 1, indicating regular or smooth series. From the storm onset, a hike in KFD of SYMH was observed, from 1 to 1.48, later reaching a maximum of 1.81(storm main phase) and then dropping to 1.45(beginning of recovery phase) and settling to 1(storm end). KFD 1.81 denotes more chaos or noisy state. For IMFBz, from the storm onset, it increased up to 1.63 from the quiet value of 1, and consistently >1.2 during the storm period, denoting sustained disturbance in IMFBz, showing enhanced turbulence in the SW-magnetosphere interaction. KFD approaching 1.6 shows the transition of Bz to anti-persistent behaviour from Brownian motion. Simultaneous spikes in KFD of indices (storm period intervals) shows a direct response of geomagnetic field changes to the input SW while asynchronous spikes (early and later quiet intervals) show internal magnetic processes and delayed responses. Intervals where KFD have synchronized peaks, elevated together, and sustaining high values shows a tight link between SW drivers and geomagnetic effects. The KFD analysis confirms that more irregular SW conditions directly lead to greater complexity and disturbance in Earth’s magnetic field.