Characterization of Continuing Current on a Global Scale

A typical lightning flash consists of discrete discharges in which current flows for on the order of a millisecond. However, there is a class of lightning in which the current can flow continuously for hundreds of milliseconds, referred to as continuing current. The current flow is accompanied by optical emission. Conventionally, investigations into continuing current use electric/magnetic field sensors and/or video observations at the ground. However, the continuous optical emission produces a unique optical signature that can be detected from space, enabling observations from space based measurements of lightning.

We exploit this signature to present results of the global distribution of lightning that contains continuing current using the Lightning Imaging Sensor (LIS). The spatial and temporal properties are derived; further, we explore the variations in the various satellite attributes, including the electrical energy. Various continental and long range networks are used to further characterize the discharges. In addition, the short-range Huntsville Alabama Marx Meter Array is used to better understand selected cases, including the detection of a continuing current signature in intracloud discharges.