The declination diagram can change with location and shows the relationship among

The declination diagram can change with location and shows the relationship among

• A. It is fixed worldwide
• B. True north, grid north, and magnetic north
• C. Grid north only
• D. Magnetic north only

Answer: (B)

The main idea here is that three reference directions—true north (geographic north), grid north (the north indicated by the map’s grid), and magnetic north (where a compass points)—are related to each other in a way that varies by location. The declination diagram maps those relationships at a given spot, showing how far magnetic north is from true north (magnetic declination) and how far grid north is from true north (grid convergence). Because the Earth's magnetic field shifts over the surface and map projections place grid lines differently across regions, this relationship isn’t the same everywhere. So the diagram communicates how all three north references relate at that location, not just one. That’s why it’s the best choice.

The main idea here is that three reference directions—true north (geographic north), grid north (the north indicated by the map’s grid), and magnetic north (where a compass points)—are related to each other in a way that varies by location. The declination diagram maps those relationships at a given spot, showing how far magnetic north is from true north (magnetic declination) and how far grid north is from true north (grid convergence). Because the Earth's magnetic field shifts over the surface and map projections place grid lines differently across regions, this relationship isn’t the same everywhere. So the diagram communicates how all three north references relate at that location, not just one. That’s why it’s the best choice.