Answer:
The condition in which the temperature of the atmosphere enhances with height in comparison to the usual reduction of temperature with altitude is known as a temperature inversion. In case when the phenomenon of temperature inversion takes place, the cold air underlies warmer air at greater heights.
The phenomenon of temperature inversion takes place in the troposphere, that is, the layer of the atmosphere nearest to the surface of the Earth. It occurs when the cold layer of air near to the surface of the Earth gets enveloped with a layer of the warm layer.
The major temperature inversions in the atmosphere take place after rain with a frontal passage or with radiational cooling.