Impact of circulation winds on the atmospheric chemistry of the hot Jupiter HD 209458b

We investigate the effects of circulation winds on the atmospheric chemistry of the hot Jupiter HD 209458b. We identify the existence of a pressure level of transition between two regimes, whose location depend on each molecule. Below this transition layer, chemical equilibrium holds, while above it, winds tend to homogenize the chemical composition of the atmosphere, bringing molecular abundances in the nightside close to those prevailing in the dayside. We find moderate abundance variations for some molecules such as CO2 between the morning and evening limbs, which would have consequences for transmission spectra that sample the planet's terminator of hot Jupiters.status: publishe