Environment and Ecology Research Vol. 7(3), pp. 121 - 134
DOI: 10.13189/eer.2019.070302
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Contribution of Excited Ozone and Oxygen Molecules to the Formation of the Stratospheric Ozone Layer

Kari Hänninen ^*
Department of Biological and Environmental Sciences, Jyväskylä University, Finland

ABSTRACT

The absorption of UV, visible and near IR radiation by O₃ produces transient, electronically excited O₃. The absorption of thermal IR radiation ( = 9.065, 9.596 and 14.267 µm) produces vibrationally excited O₃ molecules. Thermal absorption is likely the main factor in the self-decay of O₃. Photoexcitation of ground state by IR and red light radiation produces singlet oxygens and . Chemical reactions in the stratosphere produce them as well. When reacting with ozone, singlet oxygen produces O (³P) and . By doing so, they tend to maintain the prevailing ozone concentration and are thereby important for the stability of the ozone layer. During the daytime, O(¹D), and reach their maximum concentrations at altitudes of 45 to 48 km. This manifests fast ozone turnover which generates the maximum stratospheric temperature at those particular altitudes. During the night-time, the self-decay of ozone and absorption of light from the nightglows, moon and stars by O₃ and O₂ generates so much heat that the stratospheric temperature decreases by only a couple of degrees. Being a heavier gas than O₂ and N₂, ozone lacks buoyancy in the atmosphere, and it starts to descend immediately when formed. Chapman calculated that ozone in the stratosphere would descend 20 m per day. At the North and South Poles, during the four to six months of darkness in the winter, ozone descends by 2.4 to 3.6 km. This descent is likely the main reason for the stratospheric ozone depletion above the poles during winter.

KEYWORDS
Ozone Self-decay, Photoexcitation of Ground State O₂ Molecule to Singlet Oxygens by IR and Red Light, Importance of Singlet Oxygens for the Stability of the Ozone Layer, Reason for Ozone Depletion above the Poles during Winter

Cite This Paper in IEEE or APA Citation Styles
(a). IEEE Format:
[1] Kari Hänninen , "Contribution of Excited Ozone and Oxygen Molecules to the Formation of the Stratospheric Ozone Layer," Environment and Ecology Research, Vol. 7, No. 3, pp. 121 - 134, 2019. DOI: 10.13189/eer.2019.070302.

(b). APA Format:
Kari Hänninen (2019). Contribution of Excited Ozone and Oxygen Molecules to the Formation of the Stratospheric Ozone Layer. Environment and Ecology Research, 7(3), 121 - 134. DOI: 10.13189/eer.2019.070302.