= Solution
The <radiative-convective structure of the terrestrial atmosphere> reflects several processes. In the <troposphere>, absorbed sunlight heats the surface, which transfers energy upward by sensible heat and evaporation. Convection and large-scale ascent cool air by expansion; condensation releases <latent heat> and reduces the cooling rate of saturated ascent. Radiative cooling of the atmosphere balances part of this upward transport. The dry adiabatic lapse rate is $g/c_p$; moist convection generally gives a smaller lapse rate. The observed mean profile is a radiative–convective balance, not one universal dry adiabat.
In the <stratosphere>, ultraviolet absorption by ozone heats the layer and produces the mean temperature inversion, suppressing deep convection. Higher in the <mesosphere>, weaker ozone heating and radiative cooling allow temperature to decrease again. In the <thermosphere>, absorption of energetic solar radiation by the tenuous gas raises its kinetic temperature. Its low density means that a high kinetic temperature does not imply a large heat content.
Tropopause and other transition heights vary with latitude and season. Near-surface inversions and clouds further modify local profiles. <Layers of the Atmosphere by National Oceanic and Atmospheric Administration>[Jetstream, troposphere through thermosphere and their heating mechanisms]{ref}
\Image[/past-exam-of-the-atmospheric-physics-course-of-the-university-of-cambridge/2012/paper-1-ap2012-temperature-profile.png]
{title=Atmospheric temperature profile}
{source=paper-1-ap2012-temperature-profile.py}
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