TY - JOUR

T1 - Model of Daytime Oxygen Emissions in the Mesopause Region and Above: A Review and New Results

AU - Yankovsky, Valentine

AU - Vorobeva, Ekaterina

N1 - Publisher Copyright: © 2020 by the authors.

PY - 2020/1/19

Y1 - 2020/1/19

N2 - Atmospheric emissions of atomic and molecular oxygen have been observed since the middle of 19th century. In the last decades, it has been shown that emissions of excited oxygen atom O(1D) and molecular oxygen in electronically–vibrationally excited states O2(b1Σ+g, v) and O2(a1Δg, v) are related by a unified photochemical mechanism in the mesosphere and lower thermosphere (MLT). The current paper consists of two parts: a review of studies related to the development of the model of ozone and molecular oxygen photodissociation in the daytime MLT and new results. In particular, the paper includes a detailed description of formation mechanism for excited oxygen components in the daytime MLT and presents comparison of widely used photochemical models. The paper also demonstrates new results such as new suggestions about possible products for collisional reactions of electronically–vibrationally excited oxygen molecules with atomic oxygen and new estimations of O2(b1Σ+g, v = 0–10) radiative lifetimes which are necessary for solving inverse problems in the lower thermosphere. Moreover, special attention is given to the “Barth’s mechanism” in order to demonstrate that for different sets of fitting coefficients its contribution to O2(b1Σ+g, v) and O2(a1Δg, v) population is neglectable in daytime conditions. In addition to the review and new results, possible applications of the daytime oxygen emissions are presented, e.g., the altitude profiles O(3P), O3 and CO2 can be retrieved by solving inverse photochemical problems when emissions from electronically vibrationally excited states of O2 molecule are used as proxies.

AB - Atmospheric emissions of atomic and molecular oxygen have been observed since the middle of 19th century. In the last decades, it has been shown that emissions of excited oxygen atom O(1D) and molecular oxygen in electronically–vibrationally excited states O2(b1Σ+g, v) and O2(a1Δg, v) are related by a unified photochemical mechanism in the mesosphere and lower thermosphere (MLT). The current paper consists of two parts: a review of studies related to the development of the model of ozone and molecular oxygen photodissociation in the daytime MLT and new results. In particular, the paper includes a detailed description of formation mechanism for excited oxygen components in the daytime MLT and presents comparison of widely used photochemical models. The paper also demonstrates new results such as new suggestions about possible products for collisional reactions of electronically–vibrationally excited oxygen molecules with atomic oxygen and new estimations of O2(b1Σ+g, v = 0–10) radiative lifetimes which are necessary for solving inverse problems in the lower thermosphere. Moreover, special attention is given to the “Barth’s mechanism” in order to demonstrate that for different sets of fitting coefficients its contribution to O2(b1Σ+g, v) and O2(a1Δg, v) population is neglectable in daytime conditions. In addition to the review and new results, possible applications of the daytime oxygen emissions are presented, e.g., the altitude profiles O(3P), O3 and CO2 can be retrieved by solving inverse photochemical problems when emissions from electronically vibrationally excited states of O2 molecule are used as proxies.

KW - oxygen dayglow chemistry

KW - O2 photo-chemical modelling

KW - electronic–vibrational state hierarchy

KW - oxygen dayglow chemistry

KW - O2 photo-chemical modelling

KW - electronic–vibrational state hierarchy

KW - Electronic-vibrational state hierarchy

KW - O photo-chemical modelling

KW - Oxygen dayglow chemistry

KW - COLLISIONAL REMOVAL

KW - MIDDLE ATMOSPHERE

KW - electronic-vibrational state hierarchy

KW - ELECTRONIC-VIBRATIONAL KINETICS

KW - O-2 photo-chemical modelling

KW - SPECTRAL PARAMETERS

KW - 1.27 MU-M

KW - LOWER THERMOSPHERE

KW - O-2 PHOTOLYSIS

KW - ENERGY-TRANSFER

KW - HARTLEY BAND

KW - MOLECULAR-OXYGEN

UR - http://www.scopus.com/inward/record.url?scp=85083968062&partnerID=8YFLogxK

UR - https://www.mendeley.com/catalogue/fd007a45-faa1-34a9-bfc5-c1acb2167df5/

U2 - doi:10.3390/atmos11010116

DO - doi:10.3390/atmos11010116

M3 - Article

VL - 11

JO - ATMOSPHERE

JF - ATMOSPHERE

SN - 1598-3560

IS - 1

M1 - 116

ER -