Answer:
A temperature inversion can adversely affect air quality and is characterized by: 4. a layer of warm air forming above colder air.
Step-by-step explanation:
A temperature inversion is characterized by the formation of a layer of warm air above a layer of cold air, this is opposite to the normal behavior of temperature where a layer of cold air, forms above warmer air. A temperature inversion is helpful to form clouds, make them go higher or lower, and make the rain process possible.