types of fog Flashcards
radiation fog
This fog forms when all solar energy exits the earth and allows the temperature to meet up with the dew point. The best condition to have radiation fog is when it had rained the previous night. This help to moisten up the soil and create higher dew points. This makes it easier for the air to become saturated and form fog. However, the winds must be light less than 15 mph to prevent moist and dry from mixing.
precipitation fog
This is fog that forms when rain is falling through cold air. This is common with a warm fronts but it can occur with cold fronts as well only if it’s not moving too fast. Cold air, dry at the surface while rain is falling through it evaporates and causes the dew point to rise. This saturation forms fog.
advection fog
This type of fog forms from surface contact of horizontal winds. This fog can occur with windy conditions. Warm air, moist air blows in from the south and if there is snow or cool moisture on the ground it will come in contact with the warm, moist winds. This contact between the air and ground will cause the air blowing in to become cool. Then dew point rises and creates high humidity and forms fog.
steam fog
This type of fog is commonly seen in the Great Lakes but can be seen on any lake. This forms during the fall season. As summer ends, water temperatures don’t cool right away but air temperature does. As a mass of dry, cold air moves over a warmer lake the warm lake conducts warm, moist air into the air mass above. This transport between the lake and air evens out. This corresponds to the second law of thermodynamics and this law state “any two bodies that come into contact, the system will become equilibrium state.” Steam fog does not become very deep but enough to block some of the sunlight.
upslope fog
This fog forms adiabatically. Adiabatically is the process that causes sinking air to warm and rising air to cool. As moist winds blow toward a mountain, it up glides and this causes the air to rise and cool. The cooling of the air from rising causes to meet up with the dew point temperature. Fog forms on top of the mountains.
valley fog
Valley fog forms in the valley when the soil is moist from previous rainfall. As the skies clear solar energy exits earth and allow the temperature to cool near or at the dew point. This form deep fog, so dense it’s sometimes called tule fog.
freezing fog
Freezing fog occurs when the temperature falls at 32°F (0°C) or below. This fog produces drizzle and these tiny droplets freeze when they come into contact with an object. But at the same time there is sublimation going on.
ice fog
This type of fog is only seen in the polar and artic regions. Temperatures at 14 F (-10°C) is too cold for the air to contain super-cooled water droplets so it forms small tiny ice crystals.
