gravitational field. The strength of the field depends on the mass of the planet. But, unlike a billiard ball, the mass of the Earth is not equally distributed in its interior. And on the planet’s surface [...] billion tonnes of snow fall there every year. In the past, much of the snow remained on the ground, even on the outskirts. It then became compressed and added to the ice. “But over the past 20 years, we’ve [...] important factor: the seawater is currently being pulled at by the gravitational field of the major ice masses in Greenland and the Antarctic, similar to how the moon drives the tides. Should the ice melt, this