Chapman’s model for ozone concentration: earth’s slowing rotation effect in the atmospheric past

Chapman’s model for ozone concentration is studied. In this nonlinear model, the photodissociation coefficients for O2 and O3 are time-depending due to earth-rotation. From the Kapitsa’s method, valid in the high frequency limit, we find the criterion for the existence of equilibrium solutions. These solutions are depending on the frequency, and require a rotation period T which satisfies T < T1 or T > T2. Where the critical periods T1 and T2, with T2 > T1, are a function of the parameters of the system (reaction rates and photodissociation coefficients). Conjectures respect to the retardation of the earth’s rotation, due to friction, suggest that the criterion was not even verified in the atmospheric past.