Abstract Doppler frequency shifts (DFSs) recorded by continuous wave‐high frequency Doppler sounding systems and ionograms observed by five ionosondes in Taiwan and Japan are used to study three‐dimensionally seismo‐ and tsunami‐traveling ionospheric disturbances (STIDs and TTIDs) triggered by the 29 July 2025 Mw8.8 Kamchatka earthquake. Prominent STIDs in DFSs travel horizontally with the supersonic speed of 3.7 km/s, the period of 20 s, and the wavelength of 74 km, and vertically upward with the speed of sound, the period of about 40 s, and the wavelength of about 16 km. TTIDs consist of infrasonic and/or acoustic‐gravity waves, which make vertical phase speed and period difficult to estimate, whereas TTIDs travel horizontally close to the tsunami wave speed of about 200 m/s. Results show that the associated STIDs and TTIDs in DFSs are tens of thousands of times larger than the vertical fluctuations of seismic and tsunami waves on the ground.

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