Stratosphere

Starting from the edge of Troposphere to a height of 20 km from the sealevel is the Stratosphere. In this layer, temperature is essentially constant and is equal to $-56.5 ^0 C$. Upon substituting this value in the Eq.2.23 we get

$$p_2~=~p_1~\exp \left[ - {g(z_2~-~z_1)} \over {R T_s} \right]$$ (2.26)

where $T_s$ is the constant temperature of the Stratosphere. $p_1$ is the pressure at the edge of the Troposphere (i.e., at the lower edge of the Stratosphere) and is equal to 23 kPa.

Pressures at different altitudes calculated using the two formulas Eqns. 2.25 and 2.26 are shown plotted below in Fig.2.7.

Figure 2.7 : Atmospheric pressure at different altitudes