Variation with optical depth log ₁₀τ₅ of the temperature in the 3D model and in the MACKKL 1D semi-empirical model of the solar atmosphere. The temperature values in the 3D snapshots resulting from the magneto-convection simulations with small-scale dynamo action by Rempel (2014), Vögler & Schüssler (2007), and the hydrodynamic simulations by Asplund et al. (2000) correspond to the horizontal averages at each optical depth τ₅. Arrows mark the mean optical depths of formation log ₁₀ ⟨ τ₅ ⟩ for three wavelength points Δλ within the Si i 10 827 Å line, calculated using the ⟨ | B_Z | ⟩ = 80 G 3D snapshot model.