4.3. Shape of Plumes

Try these first

1. 1.

   What is the adiabatic lapse rate?

   Hint

   Think about how temperature changes with height.

2. 2.

   Define mixing height.

   Hint

   Consider where stabilization occurs for pollutant dispersion.

3. 3.

   What is the dry adiabatic lapse rate?

   • -0.0098 °C/m
   • -0.002 °C/m
   • -0.1 °C/m

   Hint

   Remember the rule of thumb for temperature decrease with altitude.

4. 4.

   True or False: The mixing height is the highest point where pollutants disperse effectively.

   • True
   • False

   Hint

   Think of mixing height as the effective boundary for dispersion.

5. 5.

   A pollutant source emits gases at 10 meters height. If the surrounding atmospheric lapse rate is -0.006 °C/m, calculate the mixing height and discuss the implications for dispersion.

   Hint

   Recall how the mixing height is defined when lapse rates intersect.

6. 6.

   Discuss how changing environmental conditions (temperature inversion) might alter expected plume behavior for a factory emitting pollutants on a warm day.

   Hint

   Visualize the inversions as a lid restricting upward air movement.