Stratosphere Chapman model

This simple oxygen-only mechanism consistently overestimates the O3 concentration in the stratosphere as compared to measured values. This implies that there must be a mechanism for ozone destruction that the Chapman model does not account for. A series of catalytic ozone-destroying reactions causes the discrepancy. Shown below is an ozone-destroying mechanism with NO/NO2 serving as a catalyst ... 

The chemistry of the stratospheric ozone will be sketched with a very broad brush in order to illustrate some of the characteristics of catalytic reactions. A model for the formation of ozone in the atmosphere was proposed by Chapman and may be represented by the following "oxygen only" mechanism (other aspects of... 

The simplest model for considering the stratospheric ozone layer is the Chapman oxygen-only mechanism (Figure 7.11), which describes the reactions steady-state ozone concentration as resulting from a... 

Although the Chapman mechanism models the general shape of the profile of stratospheric ozone correctly, it seriously overestimates its concentration. To account for this discrepancy, a catalytic process which increases the rate of step 4 occurs (Figure 7.12). Trace amounts of radicals present in the stratosphere reduce natural ozone levels below those predicted by the Chapman scheme ... 

It is not difficult to see that ozone initially forms from the oxygen present in the air. Chapman [115] introduced the photochemical model of stratospheric ozone and suggested that the ozone mechanism depended on two photochemical and two chemical reactions ... 

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