How does Subantarctic intermediate water enter the Caribbean Sea?

Subantarctic intermediate water enters the Caribbean Sea below the Anegada Passage at depths ranging from 1,600 to 3,300 feet (500 to 1,000 metres).1

This water mass is distinct from the surface and bottom layers of the sea. Once inside, it contributes to the water transported through the Yucatán Channel, where it is estimated that approximately one-fourth of the total water passing through the channel represents this deeper Subantarctic intermediate water.1