Ocean Currents. By Joanna Gyory, Lisa M. Beal, Barbie Bischof, Arthur J. Mariano, Edward H. Ryan.
European navigators in the 15th Century, not knowing about the Gulf Stream, were afraid to risk trans-Atlantic crossings to reach the Far East. Although the single-masted ships they used at that time would have been capable of sailing westward with the Trade Winds, they made little headway when sailing against the wind and so sailors presumed they would never make it back. Portugal, the reigning maritime power during this era, concentrated its resources on reaching the riches of the Orient by sea along Africa. Uncertain of whether the Indian and Atlantic Oceans were connected, Portuguese navigators nevertheless pressed south along African shores, hoping to find a way to India. Finally, after nearly seven decades of attempts, Bartholomeu Diaz accomplished the rounding of the cape in 1486. Encountering several strong gales as he neared the southern horn, Diaz dubbed the African promontory the Cape of Storms, but Portugual authorities renamed it with a calmer name, Cabo da Boa Esperanga, or Cape of Good Hope.
Although no mention of the Agulhas Current survives from his first voyage, during the second rounding by Vasco da Gama in 1497, ships logs make mention of a southward current near Algoa Bay (near present day Port Elizabeth) of such strength that the flotilla was set steadily back for three days (Steinberg, 2001). By the mid-1500's, the Portuguese knew enough about the Agulhas Current to remain well out to sea as they rounded the African horn on the way to India, but to remain near the coast, although not too close, on the voyage home. (Peterson, et al., 1996; Steinberg, 2001).
The Agulhas Current takes its name from the point of the cape, called Cabo das Agulhas (or Cape of Needles) by later Portuguese seafarers. There are two dominant views on why this name was chosen. The first claims that the sharp rocks and reefs offshore were often described as needles, which combined with the treacherous currents to claim many ships. Among Portuguese sailors, this cape also became known as the Graveyard of Ships. The alternative explanation contends that the name is derived from the discovery that at the tip of the Cape, the compass needle points due north with no deviation between true and magnetic.
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