What is the critical angle in land navigation associated with?

The critical angle in land navigation is primarily associated with magnetic declination. Magnetic declination is the angle between magnetic north (the direction a compass points) and true north (the direction of the North Pole). This angle is crucial for ensuring accurate navigation, as it affects how compass readings translate to actual geographic directions. Understanding the critical angle helps navigators make necessary adjustments to their compasses based on the local magnetic variation.

Magnetic declination varies by location and can change over time due to shifts in the Earth's magnetic field. Therefore, a navigator must account for this angle when plotting a course using a map and compass to ensure they are following the correct heading.