When should geodesic buffers be utilized in GIS?

Geodesic buffers are utilized in GIS when large distance accuracy is needed due to the curvature of the Earth. Unlike planar buffers, which are based on flat, two-dimensional projections, geodesic buffers account for the Earth's curved surface. This is particularly important over large distances, where the difference in distances can lead to significant discrepancies in results if a planar approach is used.

For example, when working with large regions or when distance measurements span significant areas, using a geodesic calculation ensures that the buffer accurately reflects the true distance on the Earth's surface. This is crucial in applications such as environmental studies, urban planning, and transportation, where precise distance calculations can impact decision-making and analysis.

In contrast, for smaller distances, the differences between geodesic and planar measurements are negligible, making them less relevant. Similarly, design purposes may not require the high accuracy of geodesic calculations, and visual representation alone does not necessitate the complexity of geodesic measurement unless precise distances are critical. Thus, when high accuracy over larger distances is essential, geodesic buffers are the appropriate choice.