MCQ Detailed View

In general, the temperature of the atmosphere decreases with height because the air becomes thinner and receives less heat from the Earth’s surface. However, there are certain conditions in which the temperature at higher altitudes becomes greater than the temperature near the ground. This unusual situation is known as temperature inversion.

Temperature inversion occurs when a layer of warm air lies above cooler air near the Earth’s surface. Instead of the normal lapse rate (decreasing temperature with height), the atmosphere shows an increase in temperature with altitude in this condition.

Several factors can cause inversion:

1. 
   

   Radiational cooling of the surface – At night, the Earth’s surface loses heat rapidly, cooling the air just above it. Warmer air remains above the cooler air.

   
   


2. 
   

   Topography – In valleys, cool air tends to sink while warmer air stays on top, creating an inversion layer.

   
   


3. 
   

   High-pressure systems – These can trap cooler air below and prevent vertical mixing, allowing a stable warm layer above.

   
   

Because of inversion, pollutants, smoke, and fog can get trapped near the surface, leading to poor air quality. This is why temperature inversion is an important concept in environmental physics and meteorology.

Looking at the options:

• 
  

  Conduction refers to heat transfer by direct contact, which is not responsible here.

  
  


• 
  

  Convection is vertical movement of air due to heating, but in inversion, convection is suppressed.

  
  


• 
  

  Radiation is emission of heat energy, but it does not explain the temperature rise with altitude.

  
  


• 
  

  Inversion is the correct explanation, as it directly describes the phenomenon.

  
  

Thus, the reason atmospheric temperature can increase at higher altitudes in certain conditions is due to temperature inversion.