2 November 2023: Maria Zamyatina
Speaker: Maria Zamyatina (Exeter)
Date: Thursday 2 November 2023
Time: 14:00
Location: Ada Lovelace Building SM1 CANCELLED due to storm disruption
Quenching-driven equatorial depletion and limb asymmetries in hot Jupiter atmospheres
Chemistry of hot Jupiter atmospheres is tightly coupled to their dynamics. An example of such coupling is a process of transport-induced quenching, which drives the composition of the upper atmosphere of a hot Jupiter away from chemical equilibrium starting at the boundary where the speeds of the dynamics and chemistry equate. In this talk, I will share our findings of the sensitivity of transport-induced quenching to planetary parameters, in particular planetary metallicity, obtained using GCM simulations of an example hot Jupiter WASP-96b. We find that metallicity-driven heating of a hot Jupiter's deep atmosphere could shift the position of the quench level boundary to pressures dominated by the jet, and cause an equatorial depletion of species sensitive to heat, like CH4, NH3 and HCN. I will close by discussing how such a depletion maps onto the planet's transmission spectrum, and how analysis of evening-morning limb asymmetries, especially in CH4 and CO2 bands, could help distinguish atmospheres of different metallicities that are fully at chemical equilibrium from those with upper parts at thermal disequilibrium.