There is also a small difference in the gravitational forces . At the equator the Earth is spinning faster than places closer to the poles since it has a greater radius from the rotational axis . This has the effect that it squishes the Earth into something called an oblate spheroid . Because of this , the equator is actually further from the Earths center than the poles or any point inbetween not counting mountains of course . This reuslts in a weaker gravitational field . The effects of this is pretty much negligable though . It only makes for a difference of about 20 ms in escape velocity between the equator and the poles . The difference in gravitational forces can make for a difference of up to half a kilogram between weighing yourself in Equador and Svalbard .