All spheres of earth are interrelated or interdependent. this means they are separate spheres and function independently they are related in that they are of earth and function for earth they all depend on each other to function; an impact to one sphere usually affects another one cannot exist without the other

Tides are caused by a differences in the gravitational force of the sun at different points on earth. differences in the gravitational force of the moon at different points on earth differences in earth’s gravitational field strength at different points on earth’s surfac fluctuations in the gravitational attraction between earth and the moon.