Ring current simulations of the 90 intense storms during solar cycle 23

All of the intense magnetic storms (minimum Dst value of <−100 nT) from solar cycle 23 (1996–2005) were simulated using the hot electron and ion drift integrator (HEIDI) model. The simulations were run using a Kp ‐driven shielded Volland‐Stern electric field, static dipole magnetic field, and nightside plasma data from instruments on the Los Alamos geosynchronous satellites. Of the 90 events, 79 had acceptable plasma boundary condition coverage (with main phase data gaps of 4 h or less) and are included in the analysis. Storms were classified according to their solar wind driver, and means and correlations were examined. It is found that for this model configuration, the HEIDI model was able to best reproduce the Dst time series for sheath‐driven events with an average minimum Dst * from the simulations at or below the observed minimum Dst * value. CIR‐driven events were the least reproducible class of storms, with simulated minimum Dst * values typically only half to two thirds of the observed minimum value. In general, there was a strong correlation between the observed and modeled minimums of Dst * and essentially no correlation between the observed minimum Dst * and the modeled‐to‐observed Dst * ratio. This implies that the size of the eventual storm is not a good indicator of whether this version of HEIDI will be able to accurately reproduce it; rather, a Kp ‐driven HEIDI simulation is consistently on the low side of predicting storm intensity, except for sheath‐driven events.