Temperature stratification (upper panel) and TKE ω (lower panel) in the region of the convective boundary, calculated with the 1-equation model (orange) and with MLT (blue). The adiabatic (∇_ad, dark grey), radiative (∇_rad: light grey, MLT: solid, 1-equation model: dash-dotted), and model temperature gradients are shown. ∇_ad is the same for the 1-equation model and MLT. For the 1-equation model, ∇ is slightly subadiabatic in the CBM region and sharply changes to ∇_rad when ω (lower panel) drops to zero. The inset in the lower panel shows the complete convective envelope. The vertical lines mark the boundaries of the convective regions (orange: 1-equation model, blue: MLT) and the helioseismic measurement (red, Basu & Antia 1997), whereas the grey shaded regions denote the uncertainty of the measurement.