Extended Data Fig. 2: K_zz profiles used in this work.

The black profile is our nominal model (where K_zz = 10⁸ cm.²s,⁻¹ constant with altitude) which results in an oxygen abundance of 0.3 times the protosolar value. The blue profile (K_zz=2.5 × 10⁶ cm.²s,⁻¹ constant with altitude) results constrains oxygen to 2.2 times the protosolar value, that is, the Juno MWR nominal measurement of⁷. An intermediate constant value of 2.5 × 10⁷ cm.²s⁻¹ (purple line) will produce the observed CO with nearly solar oxygen. The red profile (variable with altitude) indicates the presence of a stable radiative layer at depth with a transition region such that K_zz reaches our nominal value at the levels where PH₃ and GeH₄ are quenched.