Europe’s tallest sand dunes, the Pilat Dune, are now blowing in the wind, scientists say


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                La Dune du Pilat, la plus haute dune de sable d'Europe située sur la côte sud-ouest de la France, a perdu près de quatre mètres de sable à son apogée en un an à cause des vents violents, selon l'Observatoire du littoral aquitain (OCA) cette semaine.

À la mi-mai, les scientifiques ont mesuré la dune, qui se situe entre l'océan Atlantique et une forêt de pins, qui a atteint 102,5 m. Il a perdu près de quatre mètres depuis 2019, selon l'OCA, qui est chargé de surveiller quelque 230 km de côtes.

“This year, the succession of strong gales in autumn and winter would have contributed to causing a strong migration from the crest of the Dune towards the east”, which can reach up to 50 m, according to a press release published by the ‘OCA.

This drop in altitude, the largest since scientists began measuring the dunes in 2009, appears to be due to the spread of sand in the forest, which has happened in recent years.

The crest of the dune is very mobile and can move forward or backward, depending on the wind direction.

Located in the Arcachon basin in Gironde, the dune could encroach on nearby campsites as well as on the road, scientists will therefore continue to monitor movements.

The sand also progresses in the other direction, towards the ocean, but the measurements taken in the northern central and southern parts of the dunes, 3 km long and more than 600 m wide, reveal the differences in each part.

A scientist at the top of the Dunes du Pilat, in the southwest of France. © Observatory of the Aquitaine Coast, 2020.
L'OCA signale que l'érosion chronique dans le secteur nord est en cours, car le littoral s'est rétréci de plus de cinq mètres, tandis que les parties centrale et sud sont plutôt stables.

The Dune du Pilat was created millions of years ago when the mountain ranges of the Pyrenees and the Massif Central began to erode, and the neighboring rivers transported the sand to the sea. The sand along the coast is transported by sea and brought to the beach, where it blows inland.