Empirical Model of SSUSI-Derived Auroral Ionization Rates

We present an empirical model for auroral (90-150 km) electron-ion pair production rates, ionization rates for short, derived from Special Sensor Ultraviolet Spectrographic Imager electron energy and flux data. Using the Fang et al. (2010, ) parametrization for mono-energetic electrons, and the NRLMSISE-00 neutral atmosphere model (Picone et al., 2002, ), the calculated ionization rate profiles are binned in 2-hr magnetic local time and 3.6 degrees geomagnetic latitude to yield time series of ionization rates at 5-km altitude steps. We fit each of these time series to the geomagnetic indices Kp, PC, and Ap, the 81-day averaged solar F10.7 ${\mathrm{F}}_{10.7}$ radio flux index, and a constant term. The resulting empirical model can easily be incorporated into coupled chemistry-climate models to include particle precipitation effects.