'Cloud Arc Chain' Cloud Structure

And see we not sometime the eye of heaven
Dimmed with overflying clouds: there's not that work
Of careful nature, or of cunning art...
"The True and Honorable History of the Life of Sir John Oldcastle"
Attributed in part to William Shakespeare
Structure Description
Global Occurrence
Observation Diagrams

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"Cloud Arc Chain" Structure (CACS)

The neighbouring circles of the "cloud arc" structures can lie on a straight line and follow each other. Then they merge often in such a way that boundary lines disappear.
This picture differs from that, where a static group of coexisted "cloud arc" structures is observed.

The explanation of this phenomenon could be the following.
A local place on the water surface becomes warmer than its environment. Air over this place will be also warmer and rises up.
The water vapour is transported upward with warm air and as a result a "cloud arc" structure can emerge. However the size of the "heating source area" is smaller than the size of the whole "cloud arc" structures.
This "heating source area" could affect as a kind of Hotspot on air masses passing over it.
After the emergence of one "cloud arc" structure it will be shifted by the wind, which flows in upper layer, and the place for the emergence of new "cloud arc" structure will be free. It will be also shifted in wind direction, etc.
The shape of entire chain picture will depend on the wind velocity.

The structure is rarely observed above Pacific's equator area, still rarer above Atlantic close to Brazil coast and above Indian Ocean.

Global Occurrence Diagram
Global occurrence of 'Cloud Arc Chain' Structure



Two Hotspot Theories