Total conductivity

The ionic and electronic conductivity components can be added together to determine the total atmospheric conductivity:

$$\sigma = \sigma_{i} + \sigma_{e}$$ (2.20)

In Figure 2.5, the total atmospheric conductivity profile which utilizes the ``cold'' electron profile is denoted by the solid blue line. The atmospheric conductivity for the $T_{e}(E_k)$ electron conductivity is denoted by the solid red line. The realistic total atmospheric conductivity profile which would likely exist immediately prior to sprite initiation is indicated by the solid black line.