Energy dependences of the fluxes and polarization. Upper panel: Emergent spectra from the isothermal atmosphere (red curve) and from the atmosphere with the hot upper layer (black curve). Middle panel: Emergent spectra in the normal modes for the model with the hot upper layer with (solid curves) and without (dashed curves) vacuum polarization taken into account. Bottom panel: Energy dependence of the PD for the hot layer model with (blue curve) and without (red curve) vacuum polarization taken into account.