What term best describes GPS measurements affected by atmospheric conditions?

The term that best describes GPS measurements affected by atmospheric conditions is 'Atmospheric Effects.' This term encompasses the various ways in which atmospheric conditions can distort or degrade the accuracy of GPS signals as they travel from satellites to receivers. Factors such as ionospheric and tropospheric delays can significantly impact signal propagation and introduce errors in the position calculations performed by GPS equipment. By understanding atmospheric effects, surveyors can better account for these errors in their measurements and improve the overall accuracy of GPS data.

In contrast, signal reflection refers specifically to the bouncing of GPS signals off surfaces, leading to potential inaccuracies. Error dilution is a concept related to the geometry of satellite positioning and how it affects overall accuracy but does not directly pertain to atmospheric influences. Noise interference generally refers to random variations that can corrupt signals but does not specifically address the systematic errors introduced by atmospheric conditions.