The free-air gravity anomaly height correction for every meter above sea level is _____ mgal.

The free-air gravity anomaly height correction is a crucial aspect of geodesy that accounts for the change in gravity with height above sea level. This change is due to the inverse square law of gravitation, where gravitational force decreases with increasing distance from the mass of the Earth.

As we ascend above sea level, the gravitational pull decreases, and the correction factor to account for this decrease is approximately -0.3086 mgal per meter of elevation. The negative sign indicates that as height increases, the gravity measurement must be adjusted downward to reflect the decrease in gravity due to the distance from the Earth's center of mass.

This correction is vital for making accurate geophysical and geodetic measurements, especially in applications such as gravity surveying and geodetic network adjustments. Understanding this concept is essential for professionals in geodesy, as it ensures that data collected at higher elevations is corrected appropriately to be in line with sea-level measurements.