GEOG 101 Lecture Notes - Lecture 25: Rocky Mountain Foothills, Canadian Prairies, Advection
Document Summary
The most common type of fog: it occurs at night from the earth emitting longwave radiation to space thus cooling the earth"s surface. When the air cools to the dew point, fog forms. This fog develops due to the warm air cooling as it rises: it occurs when air is lifted over topographic barriers, common in the rocky mountain foothills. Fog is most common along the coast lines of all 3 oceans. Fog is least common in the prairie provinces. St. john"s has the highest annual number of days with fog (118 days: of the 100 largest cities in canada, london is the 13th foggiest city (49 days of fog per year) Assessing the stability of the atmosphere is important because it affects the vertical transport of air. Rising air cools and will eventually condense to form clouds/precipitation. Stability does not control whether air will rise or sink.
