Ithink it is the Moon's gravitational pull .
sea shore
High tides, low tides, spring tides (which are maximum high tides) and neap tides (which are the lowest of low tides).
Spring tides occur during the full moon and new moon phases. During these times, the gravitational forces of the moon and the sun align, resulting in higher high tides and lower low tides. This alignment creates the greatest difference between high and low tides, leading to the phenomenon known as spring tides.
Fifteen thousand feet.
ask some one who cares
They consider high and low tides in their journey because if it is high tide the water level will be high but if it is low tides the water level is low.
Low tides
It varies from day to day and from place to place. It is dependant upon where the Moon and Sun are in relationship to the Earth and the specific location. There are tide tables available that will give the times in key locations with directions on how to determine the difference for areas nearby. Most communities will publish the time of high and low tides in the local paper.
Tides that are not very high and not very low are called neap tides.
High tides. The others are called low tides.
Actually, there are TWO high tides and TWO low tides, on almost every day.
medium tides