Earthquakes can also make the days shorter. The 2004 earthquake that unleashed a tsunami in the Indian Ocean shifted enough rock to shorten the length of the day by nearly three microseconds.
Also known as the Chandler variation of latitude, the “Chandler Wobble” is a natural shifting of the Earth’s axis due to the planet not being perfectly spherical, and could be linked to the spinning speeds
If Earth spins faster, then it gets to the same position a little earlier. A half-a-millisecond equates to 10-inches or 26 centimetres at the equator. In short, GPS satellites would become useless.
To solve all this, if the trend for shorter days carries on for long, it could lead to calls for the first “negative leap second”. Instead of adding a second to clocks, civil time would skip a second to keep up with the faster-spinning planet.