What does a cardinal mark buoy with a black top and yellow bottom indicate?

A cardinal mark buoy with a black top and yellow bottom indicates the direction of safety and navigational information, specifically signaling that the navigable channel lies to the south of the buoy. In maritime navigation, cardinal marks are used to denote safe waters and indicate where hazards or shallow waters are located in relation to the buoy. Each configuration of colors and markings represents a different direction according to the cardinal system, which uses north, east, south, and west to guide mariners.

The black-top and yellow-bottom design specifically indicates a south cardinal mark, identifying that vessels should keep this buoy to the north when navigating the area. Understanding the meaning behind the buoy colors is crucial for safe navigation and helps mariners make informed decisions on their course.