Solar Cycle and Solar Wind Dependence of the Occurrence of Large <i>dB</i> / <i>dt</i> Events at High Latitudes

Abstract We investigate sharp changes in magnetic field that can produce Geomagnetically Induced Currents (GICs) which damage pipelines and power grids. use one‐minute cadence SuperMAG observations to find the occurrence distribution of “spikes.” Recent studies have determined recurrence statistics for extreme events charted local time spikes; however, their relation solar activity conditions wind is poorly understood. study spike during cycles 23 24, roughly 1995 2020. three hotspots occurrence: pre‐midnight region associated with substorm onsets, dawn sector often omega band activity, pre‐noon Kelvin‐Helmholtz instability (KHI) occurring at magnetopause. Magnetic perturbations are mainly North‐South substorms KHI, East‐West bands. Substorm spikes occur all phases cycle, but maximize declining phase. Omega‐band KHI confined maximum moderate driving, strong quiet high speed. show shapes these distributions do not depend on magnitude spikes, so it appears our results be extrapolated events.