Advection timescale (solid curves) and thermal diffusion timescale (dashed curves) as functions of the vertical depth in the envelope. Black curves show results from the accreting planet (run RADL27k0.01). Outside the Hill radius, at heights above the scale height of the disk, heat exchange by radiative diffusion is efficient. Inside the Hill radius, around 0.5 r_H, we find a balance between advection and diffusion, as the timescales become comparable and are on the order of 10–100 . However, closer to the core, around 0.3 r_H, we note that the diffusion timescale is much shorter than the advection timescale, which corresponds to a radiative zone in the envelope. At even closer distances to the core, within 0.2 r_H, convective-like overturning motions become the predominant mode of energy transport as heat diffusion timescales reach timescales of 10⁴ . Blue curves show the results for the same planet after the phase of solid accretion (run RADL0k0.01). Advection and radiative timescales follow a similar evolution to depth in the envelope. In the interior however, timescales increase by more than an order of magnitude.