The size of the earth’s gravitional pull or gravity acceleration g depends on the mass distribution in the earth.
The size of the earth’s gravitational pull or gravity acceleration g depends on the mass distribution in the earth. The more masses are below one up to the centre of the earth or the higher the density of this mass, the higher the gravitational pull. The local acceleration due to gravity can be measured with a gravimeter. From this, conclusions can also be drawn about the nature of the subsurface, e.g. cavities or ore deposits.
Gravitational acceleration depends on latitude and height above sea level. At sea level, at the equator g=9.780 m/s2, at the 45th parallel g=9.807 m/s2 and at the pole g=9.832 m/s2. With every additional height meter g decreases by about 3*10 -6 m/s2, as long as h is small against the earth radius.
At the equator the distance from the centre of the earth is greater and thus the gravity acceleration is lower than at the poles.
In addition, the centrifugal force counteracts the gravitational acceleration due to the earth’s rotation, so that this is lower at the equator. The effect is about 3 Gal.
The local absolute values of the acceleration due to gravity can be obtained from the Land Surveying Offices.