Which type of fog forms when moist air rises and cools?

Upslope fog forms when moist air is forced to rise along a slope or terrain, causing it to cool and condense. This process typically occurs in mountainous regions where the elevation causes the air to ascend, resulting in temperature drops as the air expands in lower pressure at higher altitudes. The rising air cools to its dew point, leading to condensation and the formation of fog.

In contrast, radiation fog develops during clear, calm nights when the Earth loses heat through radiation, cooling the surface and causing moisture near the ground to condense. Advection fog occurs when warm, moist air moves horizontally over a cooler surface, which cools the air quickly, leading to condensation. Steam fog, on the other hand, happens when cold air moves over warm water, causing water vapor to warm and rise into the cooler air, resulting in fog-like conditions.

Understanding these distinctions helps clarify why upslope fog is the correct choice for the given question about fog formation related to rising moist air.