학술논문
Solar interior-atmosphere linkages and space weather applications
Document Type
Electronic Thesis or Dissertation
Author
Source
Subject
Language
English
Abstract
The solar cycle gives rise to complex structures and dynamics on the Sun. As a result of magnetic disturbances on the Sun, large bursts of energy lead to space weather events that can be potentially harmful to life on Earth. In this thesis, we present a series of projects exploring the themes of Cosmic Ray (CR) space weather applications and understanding the solar interior-atmosphere linkage. A feasibility study was performed to determine whether the High School Project on Astrophysics and Research with Cosmics (HiSPARC) network was suitable for detecting space weather events. Using simulations and HiSPARC data, we found few events would be detectable in the nominal HiSPARC configuration, aside from the most extreme events, hence we explored an alternative configuration. We introduced a new configuration of HiSPARC station, which minimised CR energy biases and noise. This configuration was demonstrated to significantly improve the capabilities of HiSPARC as a space weather monitor and we provided compelling evidence to suggest that we should be capable of observing Ground Level Enhancements (GLEs). In addition, we showed the sensitivity would be further enhanced by using a network of detectors. Analysing long-term variations of Galactic Cosmic Rays (GCRs) versus Sunspot Number (SSN) during recent solar cycles, we explored the relationship between solar activity and GCRs. Focussing on the most recent Cycle 24, we showed it behaved in-accordance with previous even-numbered cycles. Finally, a frequency-domain analysis of over 20 years of high-cadence Birmingham Solar Oscillations Network (BiSON) observations of the Solar Mean Magnetic Field (SMMF) was presented. This provided evidence to suggest the strongest component of the SMMF is connected to Active Regions (ARs), based both on the inferred lifetime and location on the solar disc. We also searched for evidence of a magnetic signature of global Rossby modes (r modes) in the residual spectrum of the SMMF, where we did not conclusively find an r mode signal in the data.