(TE) Tides Flashcards
What is the “tidal bulge”
Two bulges of water formed from the graviational pull of the moon
How often does a tidal bulge pass over one location?
12.5 hours
What is the cause for the difference in time between Earth’s rotation and time for a tidal bulge to pass over?
30 min difference is caused by the slightly slower rotation of the moon
What is the name for the phenomenon where one tidal buldge is greater than another?
Diurnal bulge inequality
What is the name for when the moon and sun are alligned adding to the height of a tidal bulge?
Syzygy
What happens when the sun and moon are in quadratic alignment?
Tidal effects are cancelled as they are at 90 degrees
When do spring tides occur?
When there is a full and new moon - twice in a lunar cycle
When do neap tides occur?
When the moon is perpendicular to the sun - twice in a lunar cycle
What is the relative size of neap tides?
Smallest tides
What is the relative size of spring tides?
Largest tides
Aside from dirunal and lunar tidal cycles, what is the third cycle?
Annual - Equinoxes closest to sun
What is the reason for larger waves in bays and narrow straits?
Resonance of waves
Give an example where resonance causes large waves
Bay of Fundy - Canada - 15m tides
What is an amphidromic cell?
A cell of water which circulates around a point due to the coriolis effect
What is an amphidromic point?
The point which a tidal cell circles around - no change in water level