Investigation of Horizontal Magnetic Field (SYM-H) using Non-Linear Time-Series and Wavelet Analysis

Abstract

The horizontal geomagnetic field (SYM-H) is a geomagnetic field parameter for measuring the severity of geomagnetic storm. We investigated SYM-H using nonlinear time series and Wavelet power spectrum using a high resolution data of 1-minute obtained from the Flight Center Space Physics Data Facility (GSFC/SPDF) OMNIWEB interface spanning from 1st January to 31st December, 2014. Wavelet power spectrum (WPS) analysis assists in breaking down the time series of SYM-H s into different scales. The results revealed that the months of January, August and October displayed more enhancement of geomagnetic storms. The nonlinear time series modelling was also applied to study SYM-H using both the time delay and embedded dimension in computing average mutual information (AMI) and false nearest neighbours (FNN), respectively. The Lyapunov exponent (LE) was computed using the results obtained from AMI and FNN. The results revealed that LE displays positive values, indicating that SYM-H is a deterministic chaotic system.