'Coast Vortex' Phenomenon

As banked clouds
are swept apart by the wind,
at dawn the sudden cry
of the first wild geese
winging across the mountains.
Saigyo (1118-1190), translated by S. Hiroaki
Structure Description
Global Occurrence
Observation Diagrams

Home > Contents > 'Coast Vortex' Phenomenon - Description

"Convective Cells"

"Coast Vortex" Phenomenon (CVP)

The phenomenon, which was tentatively called "coast vortex", can be observed in the form of medium sized (20-150km) low cloud eddies over the water in the frontier "sea-country".
During the observations of "coast vortex" phenomena it was noticed that over the neighbouring country is nearly always clear. This could refer to high pressure area.
It is (in cases of "coast vortex") not rare that the neighbouring country has rather mountainous coast area.

The cause of the emergence "coast vortex" phenomena could be the following.
In a high pressure area above a land (not rare - above a high land) the mass of dry air sinks toward the earth's surface and flow finally apart.
There are hardly large convective cloud cells above the neighbouring sea area.
If in this area the winds in the land direction occur, they force to move the clouds in same direction.
However it is obstructed by conditions dominant over the country. The eddy can appear by air friction.
It could be the other reason: cold land air masses heat up over the water and rise.
The wind over the water affects the upward rise. The Coriolis Effect veers the clouds into appropriate direction.

The phenomenon is to be observed rarely and only in certain places with mostly more highly coastal area. Sometimes it occurs above large bays, where developing eddies flows the coastal line around.

Global Occurrence Diagram
Global occurrence diagram of 'Coast Vortex'