SHORELINE CH 1

crest

Highest point of a wave

trough

Lowest point of a wave

wavelength

The distance between any two repeating portions of a wave (e.g., two successive wave crests).

wave base

The depth in which the movement of waves can be felt, specifically by sediments. This is approximately equal to 1/2 the wavelength. Wave base can change depending on fair weather verses stormy weather.

wave break

A wave breaks when its base (the water beneath the surface) can no longer sustain its height.

surf

The mass or line of foamy water caused by the breaking of the sea upon a shore, especially a shallow or sloping shore.

wave refraction

the bending of waves so that they move nearly parallel to the shoreline

headland

Is a coastal landform, a point of land usually high and often with a sheer drop, that extends into a body of water.

bay

is a body of water partially surrounded by land.

longshore currents

A net movement that occurs as waves intersect the shoreline at non-perpendicular angles.

beach drift

is the movement of sand and sediment down the length of a beach.

beach

an area of the shoreline that is made up of deposited sediment

spit

A ridge of sediment that occurs out into a body of water, formed via longshore currents.

baymouth bar

A place where a spit extends out and covers a bay.

daily tides

the rise and fall of sea levels caused by the combined effects of the gravitational forces exerted by the Moon and the Sun, and the rotation of the Earth.

high tide

The time at which the tide reaches its highest level

low tide

The time at which the tide reaches its lowest level

monthly tides

variation in the tides due to the position of the moon and the sun relative to the earth

spring tide

Highest high tide of the month.

neap tide

Lowest low tide of the month.