Tides

What are tides?

What causes tides?

Tide waves are the [blank_start]longest[blank_end] waves on earth: their wavelength is [blank_start]half[blank_end] of the Earth's circumference. These waves are known as [blank_start]forced[blank_end] waves.

The moon's gravity [blank_start]attracts[blank_end] the ocean. Then the Motion of the Earth around the [blank_start]center of mass[blank_end] of the Earth-moon system causes a [blank_start]bulge[blank_end] on the side of the earth [blank_start]opposite[blank_end] the moon. Combined, this creates two [blank_start]bulges[blank_end].

[blank_start]High tides[blank_end]: the bulges are the crests of the planet-sized waves [blank_start]Low tides[blank_end]: the troughs, the area between the bulges

Label the image

Lunar tides:

In a 24h solar day, the moon moves [blank_start]12.2[blank_end] degrees eastward. The earth must rotate another [blank_start]50[blank_end] minutes to again place the moon at the highest position.

The sun has a greater effect on Earth's tide than the moon.

[blank_start]Spring tide[blank_end]: when earth, moon, and sun are all in a line. These are [blank_start]additive[blank_end], and correspond to the [blank_start]new and full[blank_end] moons. [blank_start]Neap tide[blank_end]: When earth, sun, and moon form a right angle. Tide [blank_start]diminishes[blank_end] the lunar tide, and correspond with the [blank_start]quarter[blank_end] moons.

Land masses obstruct tidal crests, diverting and [blank_start]slowing[blank_end] movement. This causes different patterns in the arrival of tidal crests and is influenced by [blank_start]basin shape[blank_end].

[blank_start]Semidiurnal[blank_end] tides: two high tides and two low tides of nearly equal level each lunar day [blank_start]Diurnal[blank_end] tides: on high and one low [blank_start]Mixed semidiurnal[blank_end] tides: successive high tides or low tides are of significantly different heights in the lunar day

Amphidromic points:

Tidal ranges increase with increasing distance from amphidromic points

Water flow into or out of bays and harbors is known as...

[blank_start]Flood current[blank_end]: water rushing into an enclosed area because of the rise in sea level as a tide crest approaches [blank_start]Ebb current[blank_end]: water rushing out because of the fall in sea level as the tide trough approaches [blank_start]Slack water[blank_end]: a time of no currents, occurs at high and low tides when the current changes direction

Tidal friction is gradually slowing the Earth's rotation.

What is the intertidal zone?

Check all that apply to organisms in the intertidal zone