Model of daytime emissions of electronically-vibrationally excited products of O<sub>3</sub> and O<sub>2</sub> photolysis: application to ozone retrieval

Abstract

(X 3 − g , v). In contrast to the previous models of kinetics of O 2 (a 1 g ) and O 2 (b 1 + g ), our model takes into consideration the following basic facts: first, photolysis of O 3 and O 2 and the processes of energy exchange between the metastable products of photolysis involve generation of oxygen molecules on highly excited vibrational levels in all considered electronic states -b 1 + g , a 1 g and X 3 − g ; second, the absorption of solar radiation not only leads to populating the electronic states on vibrational levels with vibrational quantum number v equal to 0 -O 2 (b 1 + g , v=0) (at 762 nm) and O 2 (a 1 g , v=0) (at 1.27 µm), but also leads to populating the excited electronicvibrational states O 2 (b 1 + g , v=1) and O 2 (b 1 + g , v=2) (at 689 nm and 629 nm). The proposed model allows one to calculate not only the vertical profiles of the O 2 (a 1 g , v=0) and O 2 (b 1 + g , v=0) concentrations, but also the profiles of2)] and O 2 (X 3 − g , v=1-35). In the altitude range 60-125 km, consideration of the electronic-vibrational kinetics significantly changes the calculated concentrations of the metastable oxygen molecules and reduces the discrepancy between the altitude profiles of ozone concentrations retrieved from the 762-nm and 1.27-µm emissions measured simultaneously.

Effect of dynamical‐photochemical coupling on oxygen airglow emission and implications for daytime ozone retrieved from 1.27 μm emission

“…One of the brightest emission features in the mesosphere is the molecular oxygen dayglow at 1.27 μ m resulting from the electronically excited molecular oxygen O 2 (a 1 Δ g ). O 2 (a 1 Δ g ) in the mesosphere is mainly produced by the photodissociation of ozone (O 3 ) in the Hartley band (200–310 nm), which makes the retrieval of O 3 from O 2 (a 1 Δ g ) photochemically feasible [e.g., Thomas et al , 1984; Sica , 1991; Mlynczak et al , 1993; Yankovsky and Manuilova , 2006]. Previously, the retrieval algorithms assumed photochemical equilibrium under which mesospheric O 3 can be inferred by the volume emission rates at 1.27 μ m [ Thomas et al , 1984].…”

Daytime SABER/TIMED observations of water vapor in the mesosphere: retrieval approach and first results

“…The most detailed kinetic model of the O 2 /O 3 photolysis products was presented by Yankovsky and Manuilova (2006), hereafter YM2006. In this model, the quantum yield of O 2 (1) molecules per O 3 photolysis event (ε) depends on the altitude (see also Fig.…”

Implications of the O + OH reaction in hydroxyl nightglow modeling

“…Although several studies have been devoted to the role of vibrationally excited species in reactions, particularly for the HO x cycle, atmospheric chemistry models of the middle-upper atmosphere neglect non-LTE (see, e.g., von Clarmann et al, 2010 and references therein). Indeed, it has become a standard procedure to consider non-LTE radiative processes associated with vibrational and rotational excitation in radiative transfer modeling and remote sensing data analysis whenever appropriate (e.g., Funke et al, 2001a,b;Kaufmann et al, 2003;Yankovsky and Manuilova, 2006), but consideration of these effects in chemistry modelling has been neglected (von Clarmann et al, 2010). One of the reasons for this, as has been pointed out Adler-Golden, 1997), is the lack of accurate state-to-state deactivation and state-specific rate constants for key reactions involved in the atmospheric cycles.…”