Radial field dependence:

Transmitting dipole moment current ^. length = 1 Am 

Background noise level above ground: 5 dBuV/m

Vertical electrical antenna:

Horizontal wire connected to average ground:

Horizontal wire connected to very dry ground:

Geometry of an earth-antenna:

View from top

View from side

Equations:

Complex wavenumber k in lossy medium:

 

 

 

 

 

(applicable if antenna length l > d and l > d)

In the air above the surface, the vertical (E-field) polarisation is doubled by the image antenna, whereas the horizontal polarization is short-circuited. 

Beneath the surface, the air acts as a magnetic wall, suppressing vertical E-fields and currents.