The diameter of the earth is approximately 12,000 km (12,000,000 metres).
This means that the total distance from the bottom of the deepest ocean to the top of the largest mountain only accounts for 1.5 percent of the diameter of the earth.
This means that the earth in reality is probably like a very round rock. The mountains and oceans are just ‘roughness’ on the surface!
The geographical relief involved in seas, mountains etc is miniscule compared to the actual spherical curviture of the earth.
If you were to shrink the earth down to the size of a billiard ball it would appear practically as smooth as one too (although it wouldn’t be a perfect sphere). So taking away the water on the surface isn’t going to make a noticable difference to its shape.
And those deepest parts of the ocean are essentially fissures, not big wide plains, so that just means that the orb is pretty much a ball with a few tiny cracks. Another analogy is that the oceans are pretty much like the skin of an apple. Insignificant in the overall shape. xo C.
Putting them on the scale of a large orange, about 4 inches (10 cm) in diameter, the irregularities on the Earth’s surface would amount to less than 0.2 millimeters, or less than one hundredth of an inch.
Well, the equatorial bulge is about 13 miles high. Is that exciting enough? On a marble 1/2 in. in diameter that would be an out-of-round of about 1.6 thousandths.