GNSS can detect the seismic atmospheric-ionospheric variations, which can be used to investigate the seismo-atmospheric disturbance characteristics and provide insights on the earthquake. This book presents the theory, methods, results, and modeling of GNSS atmospheric seismology. Sesimo-tropospheric anomalies, Pre-/Co-/Post-seismic ionospheric disturbances, epicenter estimation, tsunami and volcano ionospheric disturbances, and volcanic plumes detection with GNSS will be presented and discussed per chapter in the book.