In the convective equilibrium of the atmosphere, the air is supposed to change in density and pressure without exchange of heat by conduction; and then

ρ/ρ0 = (θ/θ0)n, p/p0 = (θ/θ0)n + 1,

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dz= 1 dp= (n + 1) p= (n + 1) R, γ = 1 + 1,
ρ ρθn

where γ is the ratio of the specific heat at constant pressure and constant volume.

In the more general case of the convective equilibrium of a spherical atmosphere surrounding the earth, of radius a,

dp= (n + 1) p0 = − a2dr,
ρ ρ0θ0 r2

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gravity varying inversely as the square of the distance r from the centre; so that, k = p0/ρ0, denoting the height of the homogeneous atmosphere at the surface, θ is given by

(n + 1) k (1 − θ/θ0) = a(1 − a/r),