Oceanography

Front 1

Backshore

Back 1

The zone of the beach between the foreshore and the berms on the coastline; only storm waves reach the backshore

Front 2

Bar

Back 2

An embankment of sand, gravel, or other particles in shallow water; may be submerged or emerged; also called a sandbar

Front 3

Beach

Back 3

Zone of loose sand, gravel, or other material extending landward from the low waterline; also called shore

Front 4

Berm

Back 4

Nearly horizontal part of the backshore of the beach; some beaches have no berms

Front 5

Breaker

Back 5

Unstable wave breaking on shore or over a reef; includes spilling, plunging, collapsing, and surging waves

Front 6

Breaker zone

Back 6

Area where deep-water waves touch bottom and become shallow-water waves

Front 7

Coast

Back 7

Strip of land extending from the shoreline inland to the first major change in land features; also called coastal area

Front 8

Coastline

Back 8

Indefinite line forming the boundary between coast and shore

Front 9

Dunes

Back 9

Ridges or mounds of loose, windblown sand

Front 10

Foreshore

Back 10

Part of the shore between the upper limit of wave wash and water's edge; also call intertidal zone

Front 11

High tide

Back 11

Highest water level or rising, normal tide

Front 12

Low tide

Back 12

Lowest water level of falling, normal tide

Front 13

Nearshore

Back 13

Zone extending seaward from the shoreline to beyond the breaker zone; also called Inshore

Front 14

Offshore

Back 14

Direction seaward of the breaker zone

Front 15

Onshore

Back 15

Direction landward from the water

Front 16

Peaking wave

Back 16

Wave that has begun to change from rounded swell to a higher, steeper, and less stable pointed wave

Front 17

Plunge point

Back 17

Point as which a plunging wave curls over and falls

Front 18

Rip feeder channel

Back 18

Drop-off parallel to the beach formed at the final breaking point of waves

Front 19

Shoreline

Back 19

Line formed when the water touches the beach at high tide

Front 20

Scarp

Back 20

Steep slope along a beach caused by wave erosion

Front 21

Surf zone

Back 21

Area extending from where waves begin to peak to the highest uprush of the waves

Front 22

Fetch

Back 22

Area of water over wind blows in a constant direction

Front 23

Spilling breaker

Back 23

Wave where white water tumbles down the face of the wave, such as Waikiki

Front 24

Plunging breaker

Back 24

Wave where the top of the wave breaks fast, forming a tube, such as Pipeline

Front 25

Crest

Back 25

Top of a wave

Front 26

Trough

Back 26

Bottom of a wave

Front 27

Swell

Back 27

Series of waves produced by a common wind source

Front 28

Tsunami

Back 28

Long-period wave produced by a submarine earthquake or volcanic eruption

Front 29

Bouyancy

Back 29

Ability of an object to float; floatation

Front 30

Stability

Back 30

Tendency of an object to maintain an upright position in the water

Front 31

Center of Gravity

Back 31

Point where the weight acts to pull an object down

Front 32

Center of bouyancy

Back 32

Point where bouyancy acts to push the object up

Front 33

When were the most devastating tsunamis to hit Hawaii?

Back 33

1946 and 1960

Front 34

Speed of a tsunami in the open ocean

Back 34

600 mph

Front 35

Wavelength of a wave

Back 35

Distance from peak to peak

Front 36

Height of a wave

Back 36

Distance between peak and trough

Front 37

Frequency of a wave

Back 37

Number of waves that pass a point in one second

Front 38

Speed of a wave

Back 38

Wavelength divided by period

Front 39

Guyot

Back 39

Submerged, flat-topped seamount

Front 40

Subduction zone

Back 40

Convergence between a sinking plate and an overriding plate

Front 41

Seamount

Back 41

Isolated volcanic peak rising from the ocean floor

Front 42

Trench

Back 42

Long, deep, narrow depression of the sea floor, having steep sides

Front 43

Trough

Back 43

Long depression of the sea floor, having gently sloping sides

Front 44

Steepness

Back 44

Ratio of wave height to wavelength