The Neutral Atmosphere Composition and Temperature

Much has been written concerning the structures and properties of the neutral atmosphere 2 5, but the details are not relevant here. Only those general features which significantly influence the chemistry of the atmosphere will be discussed and then only very briefly. 

Die increasing Tg at altitudes above the tropopause is largely due to the photochemical production of ozone via the well-known reactions  

The thick line indicates the total neutral particle density 

M can be any third body which carries away the energy liberated in the reaction but almost invariably will be N2 or 02. Destruction of the ozone also results in atmospheric heating  

Reactions (1) and (2) essentially convert solar radiant energy into thermal energy. The parameters which determine the rate of ozone formation (UV photon flux, atomic and molecular oxygen number density and the total gas number density) are not constant with altitude and so the ozone concentration and hence Tg varies with altitude. The net result is that Tg increases thoughout the stratosphere until a maximum is reached at the stratopause whence Tg begins to decrease again. 

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