Top: Kp and Dst over 4–19 March 1998. Bottom: mass density profiles at 1200 UT (LT ≈ UT + 1) over 7–19 March 1998. For each profile L = 6 is above the corresponding date label, and an asterisk identifies the plasmapause latitude given by the Moldwin et al. (2002) model. Heavy lines represent even-numbered days. Diagonal dotted and dashed lines at 7 March denote saturated plasmasphere electron and mass densities from the Berube et al. (2005) models.