Sensitivity of LF signal to global ionosphere and atmosphere perturbations in the network of stations

Variations of the LF signal from observations in 6 receiving stations during 2000-2004 are analyzed. Five stations are located in Japan (Kochi, Moshiri, Kasugai, Shimizu and Chiba) and one station is in Russia (Petropavlovsk-Kamchatski). All the stations are equipped with the identical OMNIPAL receivers. JJY (40 kHz) transmitter is situated in Fukushima prefecture (Japan). Sensitivity of the phase and amplitude of the LF signal to ionosphere and atmosphere perturbations associated with variations of the magnetic and meteorological conditions and solar activity is studied. Correlation of phase and amplitude variations of the LF signal with Dst-index, outer-zone particles (protons and electrons) with high-pitch angle is established for all the stations. It is found that LF anomalies are typical for the main phase of magnetic storm if the sudden commencement happens in the night time. The similarity of phase and amplitude anomalies to the structure of the simultaneously observed Pi3 geomagnetic pulsations is found for all the stations. Correlation between variations of atmosphere pressure and amplitude of the LF signal is established. Correlation between variations of humidity for the stations located on the coast of Japan and amplitude of the LF signal is found.