I. INTRODUCTION Edge localised modes (ELMs) are bursty, quasi-periodic expulsions of energy and particles from the plasma edge in the high-confinement state of toroidal magnetised plasmas [1–3]. ELMs originate from the steep pressure gradient pedestal in the outer closed field line region of a tokamak. A substantial release of magnetic and potential energy, caused by a rapid rise of the rate of momentum transfer through the flux surfaces, leads to enhanced transport and loss of heat and particles into the open scrape-off layer (SOL) field line region. The filamented peak heat fluxes during ELMs on the bounding divertor plates present serious restrictions on the performance of future fusion experiments like ITER [4] and necessitate the development of suitable control techniques [5–7]. ELMs generically have been observed in all divertor tokamaks since the initial discovery of the high-confinement “H-mode” state in the early 1980s [8], while characteristics like frequency and intensity are found to vary widely depending on experimental conditions [9]. Stellarator experiments also are reported to show similar bursty quasi-periodic edge activity in the presence of edge transport barriers [10]. Indication that equilibrium drifts are part of the process has been found by experimental diagnosis of an asymmetry of the energy and particle fluxes on each of the divertor plates and evidence that this is sensitive to the directions of the toroidal current and magnetic field [11–13]. Phenomenologically, edge localised mode events in tokamaks have been compared to solar flare eruptions [14, 15], and, in the cataclysmic variability of observed radiation emanating from the plasma, they may seem to bear also some remote resemblance to the outbursts of pressure-driven dwarf novae [16], although the specific instability mechanisms behind these phenomena are clearly of a substantially different nature. On the other hand, the nature of ELMs has also not yet been completely clarified, in the sense that there is no first-principles based predictive theory available. A number of charac- teristically different variations of ELMs have been observed in experiments (e.g. Type I, II or III ELMs) which may actually be caused by different instability mechanisms [17]. “Type III” ELM observations show a remarkable similarity to global bursts found in computations of drift-wave turbulence, where the turbulence generated flows and fluxes are closely tied to the self-consistent equilibrium evolution in the plasma edge [18, 19]. “Type I” ELMs in the experiment specifically show stronger magnetic activity during the 2