chapter 16 earth scinece

Question 1

what are ocean currents

Answer 1

masses of ocean water that flow form one place to another.

Question 2

what are surface currents

Answer 2

they are movements of waters that flow horizontally in the upper part of the oceans surface

Question 3

what are gyres

Answer 3

Huge circular moving currents that move within an ocean basin.

Question 4

what is the coriolis effect

Answer 4

it is when currents dont go their original direction because the earth is moving.

Question 5

ocean currents and climates

Answer 5

when currents from low latitude regions move into higher latitude regions they transfer heat form warmer to cooler areas on earth. and vice versa.

Question 6

what are upwellings

Answer 6

The rising of cold water to replace warmer surface water that has been displaced by wind.

Question 7

deep ocean circulation

Answer 7

density currents are caused by differences in density of ocean water. it creates vertical motion.

Question 8

what does evaporation do

Answer 8

Causes an increase in salinity in dryer warmer areas.

Question 9

What is sea ice

Answer 9

most water involved in density currents begin near poles

Question 10

A conveyor belt

Answer 10

The circulation map can be simplified to a conveyor belt that travels throughout the world oceans

Question 11

waves and tides

Answer 11

currents are not visible to the eye while waves and tides and waves change shorelines over time.

Question 12

what are waves

Answer 12

they are rhythmic movement that carries energy through water or space.

Question 13

wave characteristics

Answer 13

Crest-highest point
trough-lowest point
wavelength-horizontal distance between the crests of two waves

Question 14

what is frequency

Answer 14

the number of waves that pass a point in a certain amount of time.

Question 15

what is amplitude of waves

Answer 15

is the half distance of the wave height

Question 16

what is wave motion

Answer 16

water can travel a great distanec. It looks like it moves forward but it stays in about the same place

Question 17

breaking waves

Answer 17

as wave approach shore they change.
long low waves in deep water are called swells.

Question 18

what are tides

Answer 18

tides are regular changes in the elevation of the ocean surface due to the moon.

Question 19

what causes tides

Answer 19

the moon and the earth are relatively close together in space so the moons gravity exerts a strong pull on earth.

Question 20

what are some factors that effect the height of a wave

Answer 20

landforms can interrupt the waters movement
a basin at the mouth of a river can increase the tidal range
the spread and depth increases as it flows into a narrower channel.

Question 21

what are spring tides

Answer 21

are when the moon earth and sun are lined up during ht new moon.

Question 22

what are neap tides

Answer 22

are when the sun earth and moon form a right angle at 1st quarter.

Question 23

what are tidal patterns

Answer 23

ocean basins vary in size and shape and depth so coastal locations may have different tidal patterns.

Question 24

shoreline processes and features

Answer 24

beaches and shorlines are always undergoing changes as the force of the waves and currents act on them

Question 25

wave impact

Answer 25

waves along the shoreline are constantly eroding, transporting and depositing sediments, as a result many shoreline features develop

Question 26

what is abrasion

Answer 26

when waves move sediments back and forth across the shore zone.
as the wave hits land the sediments wear away rock like sandpaper.

Question 27

what is wave refraction

Answer 27

as waves reach shallow water the waves crests refracs(bends)

Question 28

whats longshore transport

Answer 28

longshore currents run parallel to the coastline that carry a lot of sediments

Question 29

what’s wave cut cliffs and platforms

Answer 29

a wave cut cliff may result if the base of a steep area that has softer rock at the base
this softer rock erodes and the rock above collapses

Question 30

sea arches and sea stacks

Answer 30

remember how headlands extend into the sea and are vigorously eroded by waves because of wave refraction.
usually the softer rock at the base erodes forming a sea cave on both sides.
eventually the erosion is deep that the two caves meet resulting in an arch.

Question 31

what is a spit

Answer 31

a spit is a beach that projects like a finger out into the water at a result of longshore drift deposits.

Question 32

what is a tombolo

Answer 32

is a ridge of sand that connects an island (or a sea stack) to the mainland

Question 33

whats a barrier island

Answer 33

they are sand deposits that are parallel the shore but are separated from the mainland by 3 to 30km.
they form along coastal plains that slope gently seaward

Question 34

what are sand dunes

Answer 34

they are hills of windblown sand making beaches more stable and lessens erosion

Question 35

whats protective structures

Answer 35

they are built to protect a coast from erosion or to prevent the movement of sand along a beach

Question 36

what is beach nourishment

Answer 36

artificially adding large quantities of sand to a beach system.