The equivalent slab thickness is a measure of the width of the shape of the vertical electron density profile of the ionosphere. The equivalent slab thickness is defined by the ratio of the total electron content (TEC) and the peak electron density NmF2 of the ionosphere’s F2 layer, cf. Jakowski et al. (2008) and Gerzen et al. (2013). The peak electron density is provided every 15 min from the Juliusruh (JR055) ionosonde stations in near real-time. At the coordinates of the ionosonde station, the slab thickness is computed by means of NmF2 and the corresponding VTEC derived from DLR’s global TEC maps.

The shape of the vertical electron density profile reflects the complexity of production, loss and transportation of plasma in the Earth’s ionosphere. A first order measure of the profile shape is the equivalent slab thickness. This ratio is very sensitive to the competition of plasma driving forces such as thermospheric winds and electric fields. Hence, this parameter is very helpful in exploring perturbation processes in the ionosphere.

URSI ID and coordinates of the ionosonde station used to calculate the equivalent slab thickness

The equivalent slab thickness is based on the Global TEC map and Ionosonde data. The quality information of the Global TEC is available under the product menu.