Coupled 1D Chemical Kinetic-Transport and 2D Hydrodynamic Modeling Supports a modest 1–1.5× Supersolar Oxygen Abundance in Jupiter’s Atmosphere

Understanding the deep atmospheric composition of Jupiter provides critical constraints on its formation and the chemical evolution of the solar nebula. In this study, we combine one-dimensional thermochemical kinetic-transport modeling with two-dimensional hydrodynamic simulations to constrain Jupiter’s deep oxygen abundance using carbon monoxide (CO) as a proxy tracer. Leveraging a comprehensive chemical network generated by Reaction Mechanism Generator (RMG), we assess the impact of updated reaction rates, including the often-neglected but thermochemically significant Hidaka reaction (\ce{CH3OH} + H → \ce{CH3} + \ce{H2O}). Our 1D-2D coupled approach supports a modest supersolar oxygen enrichment of $1.0–1.5\times$ the solar value. We also introduce a method for deriving Jupiter's $K_{\rm zz} = 3 \times 10^6$–$5 \times 10^7$ cm$^2$/s from 2D hydrodynamic modeling using the quasi steady-state method, which is also broadly applicable to exoplanet atmospheric modeling, where $K_{\rm zz}$ remains highly uncertain but strongly influences disequilibrium chemistry and observable features. Finally, our results imply a significantly elevated planetary carbon-to-oxygen (C/O) ratio of $\sim$2.9, highlighting the importance of clarifying the mechanisms behind the preferential accretion of carbon-rich material during Jupiter's formation. By integrating thermochemical and hydrodynamic perspectives, our study offers a more complete framework for constraining chemical and dynamical processes in (exo)planetary atmospheres.