Coastal Environments Exam 1

Geomorphology

the study of the characteristics, origin, and development of landforms

LIDAR

Light Detection and Ranging

Explain LIDAR

Remote imaging method that users laser light, often used by airplanes or satellites.

Multibeam Sonar

Employs an array of sound sources and listening devices to obtain a profile of a narrow strip of seafloor

Coastal Zone

Where the land meets the sea

MWL

Mean Water Level

Tidal Range

the difference in water level between a high tide and a low tide

Intertidal Zone

Land that can be submerged or exposed depending on tide level

Closure Depth

Where wave orbitals make contact with the sea floor

Shoaling

When a wave becomes modified due to wave orbitals hitting the sea floor

Breaker Zone

Where waves break

Surf Zone

The region between the breaking waves and the shore.

Swash Zone

Where land is constantly exposed due to wave cycle

Foreshore

That part of a shore that gets wet under normal conditions

Backshore

Area between dunes and the foreshore; doesn't get wet under normal conditions

Shoreface

Coastal area underwater

Offshore

Area outside the coastal area

Littoral Zone

Portion of the coastal profile where sediment can be transported by wave action

The five coastal classification strategies

Visual (What it looks like)

Genetic (How it was formed)

Process (What processes are shaping the coast)

Energy (Based on hydrodynamic energy)

Morphodynamic State (How the morphology of the coast affects wave action)

Morphodynamic State

the interaction and adjustment of the seafloor topography with fluid hydrodynamic processes

Lithosphere

A rigid layer made up of the uppermost part of the mantle and the crust.

Asthenosphere

The soft layer of the mantle on which the lithosphere "floats".

3 types of crustal plate boundaries

1. Convergent

2. Divergent

3. Transform

Convergent plate boundary

A tectonic plate boundary where two plates collide, come together, or crash into each other.

Divergent plate boundary

Boundary between tectonic plates in which the two plates move away from each other, and new crust is created between them

Transform plate boundary

Boundary between two plates that are sliding past each other.

Tidal Gauge

A mechanical instrument consisting of a stilling well and a float used to measure tidal levels

Geoid

the shape that the ocean surface would take under the influence of the gravity and rotation of Earth alone, if other influences such as winds and tides were absent.

Crustal Uplift

surface moves upward from heat beneath

Crustal Subsidence

The sinking of the crust

Erosion

Processes by which rock, sand, and soil are broken down and carried away; Opposite of deposition

Deposition

Process in which sediment is laid down in new locations; Opposite of erosion

Equilibrium Theory of Tides

Simplistic tide theory that assumes that solar and lunar gravity are the only tidal influences

24 hours and 50 minutes

Length of time of a full tidal cycle (two high tides and two low tides)

12 hours and 25 mintutes

Time between two high tides or two low tides

6 hours and 12.5 minutes

Time between a high tide and low tide, or vice-versa

Diurnal Tide

A tidal cycle of a single high tide and a single low tide each lunar day

Semidiurnal Tide

A tidal cycle of two high tides and two low tides each lunar day

Mixed Tide

The tidal pattern of two unequal high and low tides daily

False

True or False: Tidal ranges decrease with distance from amphidromic points

Amphidromic Point

Tidal Node; A geographical point where tidal height between tidal cycles is at a consistent point.

Tidal Node

Amphidromic Point; A geographical point where tidal height between tidal cycles is at a consistent point.

Tidal Datum

The reference level (0.0) from which tidal height is measured.

Tidal Range

The difference in levels of ocean water at high tide and low tide

Tidal Bore

A steep wave moving upstream at certain inlets

Deviations in tide predictions can be caused by

Storm surges, strong winds, and tsunamis

Sinusoidal Wave

a perfect wave pattern; crests, troughs, and wavelengths are at consistent patterns throughout the wave

Period

Amount of time it takes one wavelength to pass a point

True

True or False: Waves move energy, not mass

Wave Orbitals

Water within a wave moves in an orbital motion, decreasing in size the deeper below the surface it goes.

Celerity

Wave speed; Wavelength divided by Period (L/T)

Frequency

the number of complete wavelengths that pass a point in a given time

Fetch

The distance that the wind has traveled across open water

Disturbing force

The energy that causes a wave to form.

Restoring force

The dominant force trying to return water to flatness after formation of a wave.

Gravity is a

restoring force

Wind is a

disturbing force

Capillary waves

Small ripples, the first waves to form

Chop

Waves taller than a meter caused by wind speeds greater than 10 knots

Swell

long wave of water that moves continuously without breaking

False

True or False: Waves get faster and shorter as they get closer to land

Wave refraction

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