The good news is that we wouldn’t drop off if the Earth’s rotation ceased. We could walk on land around the equator if water was forced to the poles, but it would be a very hostile environment.
We are aware that the Earth’s rotation is progressively slowing down. But what would happen if our planet’s rotation on its axis were abruptly and entirely stopped by God, the Devil, or aliens? Fortunately, geographers can now provide us with the answers because of increased information about our world.
On the equator, you could round the globe while remaining exclusively on dry land, oblivious to the bitter cold at night and the sweltering heat during the day.
Of fact, the majority of our globe would quickly become highly uninhabitable if you abruptly stopped it from rotating.
While half of the planet would nearly always be exposed to the Sun’s heat, the other half would be exposed to the icy winds of space.
A small twilight region between the hot and cold parts could support life. But as the Earth made its yearly orbit around the Sun, this twilight zone would gradually encircle the planet over a year.
Let’s imagine that the oceans don’t freeze on the cold side or evaporate on the hot side to make it easier to understand what would happen. And let’s focus solely on centrifugal force, which is more appropriately known as centripetal force.
This force, which effectively pushes outwards, has caused the planet to get slightly fatter in the middle over many billion years. As a result, the diameter of the Earth as seen from the equator is currently about 21.4 kilometers larger than that seen from the poles.
But it took billions of years for this ridge to gradually form in the solid Earth. This is because the solid matter responded to the planet’s spin’s external force by moving only extremely slowly.
However, the liquid water in the oceans is much more force-responsive and mobile. Therefore, this liquid water has been raised to an “abnormal” elevation of around eight kilometers due to the Earth’s spin.
To put it another way, the water near the equator has been pushed up around eight kilometers higher than it would have been if the Earth had no spin.
However, the deepest point of the oceans now is barely 5.75 kilometers across the entire equator.
Thus, if the spin is removed, all of the water at the equator is also removed.
The oceans would gradually move from the equator to the poles if the Earth stopped spinning on its axis. Small patches of solid ground would initially emerge from the receding waters towards the equator.
The Earth would eventually be completely encircled by a massive mega-continent at the equator. On the equator, you could round the globe while remaining exclusively on dry land, oblivious to the bitter cold at night and the sweltering heat during the day.
The poles would be the logical destination for the water that fled the equatorial regions. On either side of the mega tropical continent, there would be a pair of completely separate polar waters.
Canada would be completely submerged in the north. All of Greenland, as well as the northern plains of Siberia, Asia, and Europe, would be submerged, roughly following the line of the current boundary between the USA and Canada. Spain, though, would largely remain afloat.
The new southern ocean would begin roughly on a line passing through Canberra in the present day on the other side of the equator. Madagascar would be connected to Africa, and New Guinea and Indonesia would be connected to Australia.
It turns out that the South Pole’s underwater basin is significantly larger than the North Pole’s.
This would result in a lower new southern ocean. Its sea level would be roughly 1.4 kilometers lower than the sea level of the new northern ocean since it is a bigger “bowl” with a greater capacity.
Now, the eight-kilometer-high bulge of water near the equator that we see today is caused by more than just the Earth’s rotation.
Gravity is a second consideration. The gravity is just a little bit higher near the poles because they are roughly 10 kilometers closer to the center of the Earth than the equator.
Another thing that might be causing the water to move away from the equator is this.
Our planet’s rotation is slowing down. The slowed-down Earth will have a smaller bulge and will be closer to a sphere than the faster-spinning Earth did billions of years ago when it had a larger bulge near the equator.
We have to adjust our clocks by one second every 500 days or so due to this slowing of the spin.