Advection Fog

Advection fog is a type of fog. When warm, moist air moves horizontally across a cold surface, the air is cooled to the dew point, and fog forms because of it. Usually this occurs when the wind blows the moist air over a cold surface like the ocean.  San Francisco is a place where this type of fog occurs often…almost every day.    Here are three examples.  If you’re thinking that this looks like regular fog, the difference is how it is made.



The cat that ate Beijing

have a meowtastic day 😀


Radiation Fog :D

Fog Radiating from the Earth

Fog Radiating from the Earth

The most important things needed to make radiation fog are really wet soil, light wind, clear skies, and a low afternoon dewpoint. The more things that are present, the more likely you will see fog. Really wet soils continuously put moisture into the air, making sure the dewpoint depression (difference between temperature and dewpoint) will remain low. Light wind reduces the amount of mixing of air near the earth. If winds are light, moisture evaporating from the surface will remain near the surface and not mix with drier air aloft. If wind is calm, expect fog to be very close to the ground or not there. In a calm situation with a low dewpoint depression and moist soils, expect a thick dew or frost instead of radiation fog.


Other kinds of fog in later posts. =^._.^= meow i made it don’t take credit!!!!!