Lecture 14: Tides

These flashcards cover key concepts regarding tides, their causes, types, effects, and related phenomena as presented in Lecture 14.

What are tides?

Tides are periodic, short-term changes in the height of the ocean surface at a particular place, caused by the gravitational forces of the moon and sun and the motion of Earth.

What are the two main theories that explain tides?

The Equilibrium Theory and the Dynamic Theory of Tides.

What causes the formation of tidal bulges?

The moon's gravity attracts the ocean, creating one bulge, while the inertia of Earth's rotation creates another bulge on the opposite side.

What distinguishes neap tides from spring tides?

Neap tides occur when the moon, Earth, and sun form a right angle, resulting in lower high tides and higher low tides, while spring tides occur when they are aligned, resulting in higher high tides and lower low tides.

What is the lunar day?

A lunar day is the time it takes for the moon to return to the highest position in the sky, which is about 24 hours and 50 minutes.

How does the distance of a tide-generating object affect the tide-generating force?

The tide-generating force varies inversely with the cube of the distance from the Earth's center to the center of the tide-generating object.

What are the three types of tidal patterns?

Diurnal, semidiurnal, and mixed tides.

What is a tidal bore?

A tidal bore is a high, often breaking wave generated by a tide crest that rapidly advances up an estuary or river.

How do tides affect marine organisms?

Tides affect marine organisms by causing submergence and emergence, impacting their exposure to predation and desiccation.

What is the tidal datum?

The tidal datum is the reference level to which tidal height is compared, such as mean sea surface level.