Changing Circumzenithal Arc


Occasionally just a part of the arc may be visible, and then only for a few minutes. This unusually bright fragment was seen through broken lower level cloud. If this had been a complete arc it would have been a fantastic sight. The sun altitude was 19 degrees, which is close to the altitude when this arc is at its strongest.

No enhancement was needed - this is how it came out of the camera.

Zooming in shows the fine structure of the cirrus cloud.

This composite shows the movement of the cirrus cloud through the colour bands of the arc. The small V shape on the right edge of the cloud provides a good reference. The images span about one minute in time.


Fuji Finepix S5000    10th July 2004
Wiltshire, England

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