Residents around Canada’s Bay of Fundy are among the Earthlings who are most affected by the Moon’s influence. They cope with a difference of up to 15 metres between high and low tides. (Photo: Tttrung/Wikimedia Creative Commons)
Because of the Earth’s rotation this gives us high tides twice a day, followed by low tides about 6 hours later.
“We would have less sustantial high and low tides without the Moon. However, there would still be tides, because the Sun also has a tidal effect, although it only amounts to about half that of the Moon,” explains Aksnes.
The Sun is much more massive, but also much further away than the Moon. Even though the Sun pulls on the oceans more than the Moon does, the difference between its pull on the front and back sides of the Earth is less than the case is with the Moon, and it’s this difference that determines the height of the tidal bulge.
Shorter workdays
The pulling of the seas toward the Moon not only affects seawater depths along the coasts. The Earth’s rotation is slowed down by what is called tidal friction.
The movement of the bulge of tidal water across the oceans and its attraction to the Moon acts as a brake on the Earth’s rotation. Slowly but surely the length of a day is increasing. ..."
http://sciencenordic.com/what-would-we-d…
http://en.wikipedia.org/wiki/Leap_second