There are two kinds of fog, radiation and advection.
What about sea fog?
Most sea fog is advection fog. Warm moist air runs over cool sea whose
surface temperature is below the dewpoint temperature of the air.
Thanks for that, but it seems not to explain the sharp edges that North
Sea fog has on occasion
That is due to very small variations in sea surface temperature or low-level
humidity
or the isolated but regular days when radiation fog over south Dorset
drifts out over Lyme Bay and not only becomes sea fog but expands its area
when clear of the coast.
This is advection fog - moist air moving out to sea. Probably expanding due
to further evaporation of moisture from the sea surface.
--
Freddie
Bayston Hill
Shropshire
102m AMSL
http://www.hosiene.co.uk/weather/
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