What does a course plotter assist navigators with?

A course plotter is a critical tool used by navigators to create a navigational course on a chart. This instrument allows for precise planning and visual representation of a vessel's intended route through waters, taking into account various factors such as waypoints, hazards, and navigational aids. By using a course plotter, navigators can ensure that they are selecting the safest and most efficient paths to their destinations. This tool is integral to effective maritime navigation, enabling the plotting of courses in relation to the vessel's current position, as well as accounting for currents, tides, and other obstacles on the chart.

In contrast, the other options do not relate to the primary function of a course plotter. Cargo weight calculations are typically handled by different tools and formulas, weather patterns are analyzed using meteorological tools and data, and measuring water depth is performed using soundings and echo sounders, not a course plotter. This highlights the unique role of the course plotter in navigational planning and execution.