The effects of the Sun upon the Earth's atmosphere occur in several ways. Significant electrodynamic coupling processes transfer particles and energy from the solar wind into the Earth's environment. Applied to the dynamical characteristics of high-intensity, long-duration, continuous auroral activity (HILDCAA) and non-HILDCAA events, nonlinear analysis tools like RQA aid to unravel peculiarities related to two concurrent space mechanisms known as magnetic reconnection and viscous interaction.

The relative ionospheric opacity meter ("riometer") is a traditional instrument for measuring the degree to which cosmic noise is absorbed by the ionosphere and therefore how energetic the particles – electrons, protons etc. – are that cause the ionisation. We identify the same signatures in the "hour-to-days" timescale variability as reported in solar and geomagnetic disturbances. The result demonstrates the relationship between riometer data and the underlying physics for different timescales.

We use visibility graphs to characterize asymmetries in the dynamics of sunspot areas in both solar hemispheres. Our analysis provides deep insights into the potential and limitations of this method, revealing a complex interplay between effects due to statistical versus dynamical properties of the observed data. Temporal changes in the hemispheric predominance of the graph connectivity are found to lag those directly associated with the total hemispheric sunspot areas themselves.