What is the purpose of a Declination Diagram?

The purpose of a Declination Diagram is to illustrate the difference between True North, Grid North, and Magnetic North. This is crucial for navigation, as these three points of reference do not align perfectly due to the Earth's magnetic field variations and the spherical shape of the Earth.

True North refers to the geographic North Pole, where the longitudinal lines converge. Grid North is the north that is indicated by the grid lines on a map, which may not perfectly align with True North due to map projections. Magnetic North is the direction that a compass points to, which is influenced by the Earth's magnetic field and can shift over time.

Understanding the differences between these north references allows navigators to make accurate adjustments to their bearings when plotting courses or triangulating positions on a map. This ensures precise navigation and helps prevent errors that could arise from misunderstanding these directional indicators.