Mixing height, also known as mixing depth, is the height at which pollutants can disperse in the air.

 Mixing height, also known as mixing depth, is the height at which pollutants can disperse in the air. It's an important parameter for atmospheric pollution models, which use it to forecast air quality. 

Here are some things to know about mixing height:

How it's measured

Mixing height is measured in feet or meters above ground level. One way to determine mixing height is to draw a line from the ground surface's temperature and elevation, with a slope equal to the dry adiabatic lapse rate. The height where the line intersects the 2 PM temperature profile is the mixing height. 

How it changes

Mixing height can change throughout the day: 

Nighttime: During surface temperature inversions, which usually happen at night with clear skies, mixing height is zero and smoke dispersion is minimal. 

Afternoon: Pollutants released at the surface in the afternoon won't mix beyond the mixing height. 

How it affects air quality

A greater mixing height means a larger volume for diluting pollutants. A day with a high mixing height can lower surface dew points and increase surface temperature.