The total electron content derived by existing ground-based GNSS (Global Navigation Satellite System) receivers is used to construct a network of space buoys for real time monitoring traveling ionospheric disturbances triggered by tsunami waves. This space buoy network shall act as a tsunami early warning system confirming the tsunami origin and propagation.The total electron content (TEC) derived by existing ground-based GNSS receivers for the first time can be employed to detect traveling ionospheric disturbances induced by tsunami waves. A dense ground-based GNSS receiving network allows us pioneering to observe the tsunami origin and confirm the tsunami occurrence. Networks of existing ground-based receivers of IGS (International GNSS Server) can be used to construct a global ionospheric tsunami early warning system.Networks of existing ground-based GNSS (Global Navigation Satellite System; GPS, GLONASS, Galileo, BeiDou) receivers of IGS (International GNSS Server) can be used to construct a regional or global ionospheric tsunami monitoring and early warning system.