What does declination refer to in navigation?

Declination in navigation specifically pertains to the angular difference between true north and either magnetic north or grid north. This measurement is essential for navigators as it helps them to accurately align their compass readings with true geographic coordinates. Knowing the declination allows navigators to adjust their headings to ensure that they reach their intended destinations correctly.

The importance of this concept arises from the fact that compasses do not always point to true north due to variations in the Earth's magnetic field. Therefore, understanding declination helps in making the necessary corrections to account for these discrepancies. Other options, such as measuring distances or changes in elevation, do not relate to the angular considerations inherent in declination. This highlights why the focus on angular distance is vital for successful navigation.