In a phenomenon known as “the Brocken spectre”, the ghostly figure appeared Sunday January 28 on the dune, when local photographer Florian Clément began capturing these images and video, reports explained.
Rather than a supernatural being, this is actually a natural phenomenon that takes place when bright sunlight on one side hits a cloud or fog on the other, and an object - such as a human being, for example - is positioned in the middle.
The object or body then appears as a huge, ghostly figure with a rainbow-like halo around it.
The halo is actually a separate phenomenon again, and a result of the fog or cloud itself. It is often known as the “Ulloa's ring”, or - as its appearance might suggest - a “fogbow”.
The Brocken spectre does not only appear in the Gironde; indeed, the name itself comes from the highest peak of the same name in the Harz mountain range in Germany (and is known in German as the Brockengespenst), and is often seen in mountainous or especially high-up places.
This is not the first time the phenomenon has been witnessed on the Dune of Pilat (which is the tallest sand dune in Europe, and found in La Teste-de-Buch in the Arcachon Bay area, 60 km from Bordeaux).
A “spectre” was also seen there in 2016, according to Mr Clément himself, whose experience was recounted on the Météo du Pays de Buch Facebook page.
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