Atmospheric refraction tends to reduce the effect of earth curvature by approximately what percentage?

Atmospheric refraction affects how we perceive the Earth's curvature due to the bending of light rays when they pass through different layers of the atmosphere. This bending causes objects to appear higher than they actually are, which effectively reduces the impact of the curvature of the Earth on observational measurements.

The commonly accepted value for the reduction of curvature due to atmospheric refraction is approximately 14%. This means that when observing long distances, the Earth's curvature appears less pronounced due to this optical phenomenon. Therefore, selecting the value of 14 is correct as it reflects the approximate percentage by which atmospheric refraction can alter our perception of curvature in practical geodetic surveying tasks.

The other options do not reflect this commonly recognized percentage, highlighting the importance of understanding atmospheric conditions when conducting precise geodetic measurements.