An Overview of Solar Radio Type II Bursts through analysis of associated solar and near Earth space weather features during Ascending phase of SC 25

Abstract. Type II solar radio bursts are the signatures of particle acceleration caused by shock waves in the solar atmosphere and interplanetary space. Being electromagnetic radiation that travel at the speed of light, they can serve as ground observed data to provide early notice of incoming solar storm disturbances. An observational overview of 31 Type II bursts which occurred in the period between May 2021 to December 2022 is made. We analyzed associated parameters such as bandwidth, drift rates, starting frequency to evaluate their dynamical parameters such as the shock and Alfvén speeds to estimate the Alfvén Mach number as well as the coronal magnetic field strength using Rankine-Hugoniot relation. We also evaluated accompanying space weather implication in terms of ionospheric total electron content (TEC) enhancement. At heliocentric distance ∼ 1−2 R⊙, the shock and the Alfvén speeds are in the range 504–1301 km s⁻¹ and 368–837 km s⁻¹, respectively. The Alfvén Mach number is of the order of 1.2 ≤ M_A ≤ 1.8 at the same heliocentric distance, and the magnetic field strength shows excellent consistency and could be fit with a single power-law distribution of the type B(r) = 6.56 r ^−3.92 G. The study finds that 15/31 type II radio bursts are associated with some aspects of space weather such as radio blackouts and/or polar cap absorption events, that are the signature of solar proton enhancement and solar energetic particle events. Observed and analyzed Type II events correlated well with observed ionospheric storm indicated by the TEC enhancement. The findings from this study indicate that through analysis of type II SRBs observed from the ground and their physical features characteristics, it is possible to monitor the current progress of solar cycle 25 and predict the intensity of associated space weather phenomena.