What is one impact of magnetic declination on surveying?

Magnetic declination, also known as magnetic variation, is the angle between magnetic north and true north. It plays a significant role in surveying, particularly in how accurately compass measurements can reflect true geographic directions. When using a compass, surveyors rely on it to orient themselves correctly on a given site, which is crucial for measuring angles and distances accurately.

If a surveyor does not account for magnetic declination, the compass readings may lead to errors in positioning and alignment, resulting in inaccuracies in the survey data collected. This is particularly important when laying out property boundaries or aligning features on a site plan, where precision is key.

While the other choices mention aspects of surveying that are important, they do not directly relate to the effect that magnetic declination has on compass accuracy in navigation and orientation tasks. Therefore, understanding and adjusting for magnetic declination is critical for surveyors to ensure accurate results and reliable data in their work.