On this day in history,...

...in 1513, Spanish explorer Juan Ponce de León set sail from Puerto Rico with three ships, unknowingly on a course that would lead to the first documented European encounter with the Gulf Stream. As his fleet headed northwest in search of new lands, the ships entered an unusually strong current flowing through the Straits of Florida, one that would baffle the crew and challenge their progress.

The expedition reported that, despite favorable winds and full sails, the ships were making little or no headway—or even drifting backward. What they had encountered was the fast northward flow of the Gulf Stream, a powerful western boundary current transporting warm waters from the Caribbean toward the North Atlantic. Although the explorers could not name or explain the phenomenon, their observations represent the earliest written account of this major oceanic current.

From a navigational perspective, the effect was counterintuitive. Sailing toward the northwest, the fleet should have been aided by a northward current. However, the geometry of their route—likely crossing the current obliquely or encountering turbulent margins—may have led to lateral drift or effective resistance, especially without an understanding of how to navigate with or across such powerful flows. Additionally, interactions with eddies, countercurrents, or the strong gradient near the core of the Gulf Stream could have compounded the disorientation.

Though this first encounter was not understood in scientific terms, it laid the groundwork for future navigators to recognize the existence of a "river in the ocean." Over 250 years later, Benjamin Franklin and Timothy Folger would produce the first scientific chart of the Gulf Stream, informed by the knowledge of whalers who had long exploited the current for faster transatlantic crossings.

Today, the Gulf Stream is known as a key component of the Atlantic Meridional Overturning Circulation, influencing climate, weather, marine ecosystems, and global heat transport. Its first recorded impression on European explorers, however, dates back to that March day in 1513, when the sea seemed to push back against the sails.

Sources

• Davis, T. Frederick (1935). History of Juan Ponce de León's Voyages to Florida. Florida Historical Quarterly, Vol. 14, No. 1, pp. 3–27.
• Vernet, T. (2006). L'invention du Gulf Stream par les Européens : Ponce de León, Benjamin Franklin, et la circulation océanique. Revue d’Histoire Maritime, 6, pp. 95–112.
• Acontece que no es poco | 27 de marzo de 1513: Descubierta la Corriente del Golfo… un río en mitad del océano https://go.ivoox.com/rf/143978947 (in Spanish).