The Loop Current

The Loop Current

The Loop Current transports warm Caribbean water from the Yucatan Channel between Cuba and Mexico into the Gulf of Mexico. The current then flows north, makes a southeasterly loop towards the Florida Straits, and enters the Atlantic Ocean between the Florida Peninsula and the Bahamas where it becomes the Florida Current. The Loop Current is with a speed of about 3km/h one of the fastest currents in the Atlantic Ocean. It is about 200 – 300 km wide and 800 m deep. In summer and autumn, the Loop Current forms 80 – 150 m deep layers of very warm water, which can serve as important source of energy for hurricanes.

The Loop Current almost regularly “throws off” rings of warm water every 6 – 11 months that exhibit anticyclonic circulation, i.e. a clockwise rotating ring that separates from the main current. This ring of warm water slowly drifts west-southwest towards Texas or Mexico with a speed of about 3 – 5 km per day. This structure is called the “Loop Current Eddy” and can serve as a source of additional energy for the intensification of hurricanes that cross  the bay.

The image from the satellite SLSTR Sentinel-3  shows the beginning of the formation of such a ring. It began to appear on February 20th – 21st and formed on March 5th – 6th. Since then, it has not changed its location (approximate coordinates of the center of the ring: 25.85°N, 88.8°W). The diameter of the ring is about 330 km and the thickness of the ring approx. 60 – 80 km.  The water temperature in the ring is ca. 26 – 27°C; it is about a 1°- 1.5° colder inside the ring and 1.5° – 2.5° colder outside.