The Earth currently rotates at a very fast speed. What would happen if it began to rotate more slowly?
The Earth rotates around its own axis once every 24 hours — and we should be grateful for that. If the planet rotated more slowly, the climate, oceans and weather would be affected in some very unpleasant ways.
The slower rotation would result in greater differences between daytime and nighttime temperatures. No one can say at what point this would make the Earth uninhabitable, but a day that lasts as long as a week would create extremely hot days and cold nights, and would result in the tropics becoming a hostile environment for most life-forms.
A slower rotation would also cause other changes, such as a weaker magnetic field and the formation of new oceans and landmasses. Weather systems would change radically, as would ocean currents, which would likely cause considerable climate change, given the vital role they play in distributing heat.
What would happen?
1. Ocean water moves toward the poles, because gravity is stronger there. The result is major flooding.
2. While the water at the poles gets deeper, at the equator it gets shallower, and new landmasses appear.
3. The new landmasses at the equator will eventually meet, while the oceans will merge into one northern and one southern ocean.
Fast rotation causes a stormy globe
If Earth’s rotation increased, days would be shorter and colder, and the climate would become stormier. Though the friction between Earth’s surface and the atmosphere would curb wind velocities, we would constantly experience hurricanes with winds of over 300 mph.