A two-step ring current decay time model during the passive recovery phase of magnetic storms

► We describe a very complex system by a simple two-step model. ► A resistive force explains the early fast recovery when ring current is asymmetric. ► Once the partial ring declines the late recovery is associated to an exponential decay. ► The ring current decay time grows linearly with time during the Dst early fast recovery. ► Eventual abrupt pressure enhancements could delay the start of the early fast recovery.