a) absolute values of eigenfunctions for the n = 28 mode obtained with the MAD code with β = 0.2–1.2i; first and second terms in the right hand side of Eq. (16) (blue and green respectively), perturbation of the local turbulent pressure given by Eq. (16) (red), and of the nonlocal turbulent pressure (cyan) b) real part of the coefficient for the perturbation of the thermal pressure in Eq. (16), Re(Π), the ratio of the local turbulent pressure to the thermal one, p_turb,l/p_th. c) cumulative contribution to the frequency shift of each decomposed component of Π (Eq. (17)) defined by Eqs. (25) and (26). d) real parts of the decomposed components of Π (Eq. (17)). The vertical dashed line indicates the upper boundary of the convection zone determined by the Schwarzschild criterion.