Azimuthally averaged cooling timescale in units of the local orbital period of the disk after 1000 and 5000 planetary orbits for HD 163296 and AS 209, respectively. Differences between locally isothermal and radiative models become clear in the inner disk, where the cooling timescale corresponds to a non-negligible fraction of the orbital period (roughly 1–10% near the planet, and comparable to the orbital period farther in). In the outer disk, cooling is sufficiently fast so that the two models overlap as far as azimuthally averaged profiles are concerned.