Fig. 11

2D topography input model. a Geometry of the setup from a vertical cross-section, showing the topography of the model. The hill is a smooth vertical extension to a homogeneous background with \(\rho =100\,\Omega \, \text {m}\), with a variable symmetric height profile reaching up to 100 m, and a lateral extent in x direction of 2.4 km. Input model dimensions are \(4 \times 10 \times 5\) km. b The model domain is indicated by a yellow rectangle. Air height is 2.5 km, and the depth of the input model is increased by 5 km. The spacing for the inner grid is of \(\text{d}x=250\) m, \(\text{d}y=500\) m, and \(\text{d}z=250\) m. The width of the boundary regions surrounding the inner model are 4.9 km in the x and z directions, and 9.75 km in the y direction. This computational grid has dimensions of \(x\in [-6.9,6.9]\) km, \(y\in [-14.75,14.75]\) km, and \(z\in [0,17.35]\) km