Immunity of the SR amplitude to solar disturbances

The key finding of the entire cluster: the amplitude of the Schumann resonance is to a large extent immune to solar disturbances. The intensity of the resonance is governed predominantly by lightning activity inside the cavity (the energy source), not by the instantaneous state of the ionosphere. Solar influences therefore manifest themselves mainly in the frequency and damping of the modes, not in the amplitude Satori 2016.

This has a fundamental practical consequence for data interpretation: an observed decrease or increase in the SR amplitude should primarily be attributed to changes in global lightning activity, whereas frequency shifts may originate from the solar modulation of the upper boundary of the cavity. Confusing the two would lead to erroneous conclusions — for example, to mistakenly attributing changes in amplitude to "space weather".

This separation of roles (lightning governs the amplitude, the ionosphere governs the frequency and damping) is also a guide for popular interpretations of the SR: claims about strong solar "jumps" in the intensity of the resonance have no support in the measurements.

*Cluster H file — part of the Schumann resonance knowledge base.*