The sporadic sodium layer: a possible tracer for the conjunction between the upper and lower atmospheres

In this research, we reveal the inter-connection between lightning strokes, reversal of the electric field, ionospheric disturbances, and a sodium layer (NaS), based on the joint observations by a temperature/wind (T/W, where the slash means “and”) lidar, an ionosonde, an atmospheric electric mill, a fluxgate magnetometer, and the World Wide Lightning Location Network (WWLLN). Our results suggest that lightning strokes could trigger or amplify the formation of an NaS layer in a descending sporadic E layer (ES), through a mechanism that involves the overturning of the electric field. A conjunction between the lower and upper atmospheres could be established as follows by these inter-connected phenomena, and the key processes could be suggested to be: lightning strokes → overturning of the electric field → ES generating NaS.