Winter depressions turn this Atlantic gulf into a ship-breaker
The Bay of Biscay—also Gulf of Gascony—opens from Spain’s north coast past Cape Ortegal along western France as a northeast Atlantic gulf south of the Celtic Sea. Average depth is 1,744 metres and the floor plunges to 4,735 metres, yet wide shelf shallows brew the notorious winter seas.
The bay's coast runs west along northern Spain from the French border to Cape Ortegal and north along western France to Point Penmarc'h; the International Hydrographic Organization simply joins those two capes. Spaniards call it the Gulf of Biscay, the French the Gulf of Gascony, and the English name comes from Biscay, probably meaning the western Basque districts. Romans in the first century BC knew it as the Bay of the Cantabri and the Sea of the Galicians, some medieval maps label it the Basque Sea, and the Spanish still call its southern stretch the Cantabrian Sea.
Its violence has a physical cause: parts of the continental shelf reach far into the bay, leaving broad shallow areas where waves build steeply. Winter storms are frequent and some of the Atlantic's worst weather strikes here, with freak waves, and until fairly recently merchant ships regularly went down. Depressions sweep in from the west and either head north to Britain or cross the Ebro valley and revive as Mediterranean thunderstorms, bringing steady drizzle ashore under local names such as sirimiri and orballo. Rapid pressure drops can whip up hurricane-like windstorms called galernas, such as Cyclone Klaus. In late spring and early summer a fog triangle blankets the south-western half.
A branch of the Gulf Stream, the Rennell Current, circles anticlockwise along the shelf edge and keeps temperatures mild. Dozens of rivers drain in, among them the Loire, Garonne, Dordogne, Adour and Nervión, and the shore holds cities including Nantes, La Rochelle, Bordeaux, Biarritz, San Sebastián, Bilbao, Santander and Gijón.
The water has seen much fighting and loss. Spain beat an English fleet here in 1592, and British and French fleets clashed off Brittany in 1795. The USS Californian hit a mine and sank in 1918, and the SS Afrique drifted onto a reef in a 1920 storm with 575 dead. In December 1943 two British cruisers fought German destroyers in the bay, and U-boat crews came to call it the Valley of Death.
Source: Bay of Biscay
