5: Fog Formation

Question 1

Types of Fog

Answer 1

1. Advection
2. Valley
3. Radiation
4. Steam (evaporation fog)
5. Frontal (evaporation fog)

Question 2

Advection Fog

Answer 2

Warmer, moist air moves over a colder surface and its temperature drops

Question 3

Valley Fog

Answer 3

Air cools at higher elevations. Cold air drains downslpe into valley and cold air reduces air temperature in valley to condensation point and fog forms.

Question 4

Radiation Fog

Answer 4

Heat radiating from the surface at night cools the bottom air until it reaches saturation. Fog forms first at the surface, thickening as cooling continues

Question 5

What are the two evaporation fogs

Answer 5

1. Steam fog: fog forms on warm water when air is cool
2. Frontal fog: warm, moist air overruns a shallow layer of cold air near the surface, as well as evaporation of warm precipitation into the cold air