Abstract
We present a comprehensive multi-parametric analysis of Lithosphere– Atmosphere–Ionosphere Coupling (LAIC) processes associated with the M = 8.8 earthquake that struck offshore Kamchatka, Russia, on 30 July 2025 (29 July 2015; 23:24:52 UTC). Thermal observations revealed coherent pre-seismic irregularities in near-surface air temperature, relative humidity, and atmospheric chemical potential (ACP), with maximum intensification occurring 1–2 days before the event, followed by rapid co-seismic dissipation and post-seismic recovery. Acoustic channel analysis revealed considerable enhancements in atmospheric gravity wave (AGW) potential energy, as computed from ERA5 reanalysis datasets, 3–5 days prior to the earthquake, with a co-seismic peak and weaker post-seismic irregularities at higher altitudes. Electromagnetic signatures manifested in both lower and upper ionospheric layers. Very-Low-Frequency (VLF) sub-ionospheric propagation from the NPM transmitter, continuously monitored at the PTK (Petropavlovsk-Kamchatsky) station in Kamchatka, Russia, exhibited both positive and negative deviations in amplitude and phase during the preparatory phase. VLF amplitude exhibited wavelike deviations consistent with AGW periods, peaking one day prior to the earthquake. Ionospheric Vertical Total electron content (VTEC) showed coherent pre-seismic maxima 2–3 days before the main shock. Together, these thermal, acoustic, and electromagnetic observations strongly suggest a consistent pre-seismic build-up, co-seismic dissipation, and post-seismic recovery, providing a robust multi-channel imprint of the Kamchatka earthquake and highlighting the importance of integrated multi-parameter approaches for understanding earthquake preparatory dynamics.