FAA Aircraft Dispatcher Practice Exam

What characterizes Advection fog?

1. Occurs in urban areas

2. Results from moist air moving over colder surfaces

3. Forms exclusively at night

4. Always associated with thunderstorms

The correct answer is: Results from moist air moving over colder surfaces

Advection fog is characterized by moist air moving over colder surfaces, which leads to the cooling of that air and the subsequent condensation of water vapor, forming fog. This process can occur when warm, moist air travels horizontally (advection) over a surface that is significantly cooler, such as a cold ocean current or a snow-covered land area. As the air cools, its capacity to hold moisture decreases, resulting in the formation of fog. The other options do not accurately define advection fog. For instance, it is not limited to urban areas, as it can form in various environments. While fog can occur at night, advection fog can also form during the day. Additionally, it is not inherently associated with thunderstorms; its formation is primarily related to the temperature differential between moist air and colder surfaces. Understanding these characteristics is essential for recognizing advection fog in various meteorological conditions.