Temperature Inversion

• Usually, air is cooler the higher it gets in the atmosphere. But over an urban heat island, the opposite can happen. This is called a temperature inversion.
• The warm air can act as a lid, trapping smoke and other pollutants at the surface.
• These pollutants can cause health effects for city residents like coughing and asthma.

Temperature inversion showing smoke trapped by a layer of warm air. Source: WeatherSTEM