When are geodesic measurements typically used?

Geodesic measurements are typically employed in an unprojected map because they account for the curvature of the Earth when measuring distances and angles. This is essential for applications that involve large areas or distances, as they ensure accuracy in spatial relationships over the Earth's surface. When maps are unprojected, they do not apply a specific coordinate projection that could distort distances; therefore, using geodesic measurements helps maintain fidelity to true Earth measurements.

In contrast, detailed maps often use various projections that can introduce distortions in scale and distance, making geodesic calculations less relevant. Likewise, short distances typically do not justify the complex calculations necessary for geodesic measurements, as planar approximations work adequately. Urban planning, while spatially complex, often employs projected maps for better usability and detail in managing infrastructure and land use, which would not prioritize geodesic methods.