COASTAL HAZARDS

Question 1

often called shorelines, are a critical component of the biosphere because a large number of species are connected in some way or another to the unique habitats found at this interface between the land and sea.

Answer 1

Coastlines

Question 2

are areas where tectonic forces deform and uplift the land. They are usually rugged and irregular, with beaches sometimes being restricted to coves and inlets.

Answer 2

Active shorelines

Question 3

are areas with
little to no tectonic activity,
commonly resulting in a relatively
straight coastline with flat-lying
terrain. Ex. U.S. Gulf and Atlantic

Answer 3

Passive shorelines

Question 4

The periodic rise and fall of sea level is known as

Answer 4

ocean tides

Question 5

This complex interaction creates a net outward force, called

Answer 5

tidal force,

Question 6

high tides and two low tides each day (approximately __________ passes
between two high tides). Note that tides also occur on large lakes, but the rise and fall is

Answer 6

12 hours and 25 minutes

Question 7

refers to the difference in sea level between high and low tides.

Answer 7

Tidal range

Question 8

occurs when the Moon and Sun periodically line up such that their gravitational
effects reinforce one another.

Answer 8

Spring tide

Question 9

occurs when the gravitational pull of the Moon and Sun are at right angles which
tend to cancel their tidal effects on one another.

Answer 9

Neap tide

Question 10

++In addition to orbital influences, tidal range varies depending on latitude, water depth, shape
of the shoreline, and the presence of large storms.++

Question 11

are strong localized currents during high tide formed by the surface of
the sea sloping towards the shore which generates mechanical energy that forces
water to funnel up into inlets and river channels.

Answer 11

Tidal currents

Question 12

involve the physical movement of water molecules from one
location to another

Answer 12

Ocean currents

Question 13

are large-scale currents in the open water near the surface of the
sea which are driven mainly by winds blowing consistently in the same direction.

Answer 13

Surface currents

Question 14

are formed in response to differences in ocean temperature and salinity. Cooler and more saline water is relatively dense which causes it to sink and
flow toward areas where water is less dense.

Answer 14

Density currents

Question 15

refer to density-driven currents that circulate enormous volumes
of water, both vertically and horizontally, in a convective manner between tropical and polar regions.

Answer 15

Ocean Conveyor

Question 16

++Density and wind-driven currents transfer vast amounts of heat energy from the Tropics toward higher latitudes (influence the global climate system) and also transport nutrients into the ocean.+++

Question 17

transport energy through water such that water molecules move or vibrate in a circular manner.

Answer 17

Water waves

Question 18

As the wave continues toward shore, this causes a progressive decrease in velocity along the length of the wave, forcing it to bend in a process called

Answer 18

wave refraction

Question 19

is a wave whose amplitude reaches a critical level at which some process can suddenly start causing large amounts of wave energy to be transformed into turbulent kinetic energy.

Answer 19

Breaking wave

Question 20

refers to the area where the waves break

Answer 20

Surf zone

Question 21

is an ocean current that flows parallel to the shore and is caused by large swells Iseries of waves) sweeping into the shoreline at an angle and pushing down the length of the beach in one direction.

Answer 21

Longshore current

Question 22

is the process of transporting material along a coast by waves that approach at an angle to the shore but recede perpendicular from it.

Answer 22

Longshore drift or beach drift

Question 23

interaction between waves and a landmass can cause the shoreline to slowly move landward, a process referred to as

Answer 23

shoreline retreat

Question 24

are points of land that are just seaward and areas where waves first make contact with land

Answer 24

Headlands

Question 25

are elongate deposits of sediment that parallel the shore and are separated from the mainland by open water, lagoons, tidal mudflats, or saltwater marshes

Answer 25

Barrier islands

Question 26

result from the complex interaction between waves, sea level change, and sediment supply

Answer 26

Barrier islands

Question 27

In general, most barrier islands are no
higher than _____ above sea level, but their shape varies depending on the relative

Answer 27

6m

Question 28

are elongated sediment deposits separated from the mainland by open water or wetlands.

Answer 28

Barrier islands

Question 29

to refer to large, rotating low-pressure storm systems that originate in tropical oceans.

Answer 29

Topical cyclones

Question 30

Winds and low pressure within a hurricane produce a rise in sea level called a

Answer 30

storm surge

Question 31

The unusually strong winds associated with hurricanes result from the circulating air masses within the storm.

Answer 31

High Winds

Question 32

the lowest category has winds of at least 74 miles per hour anything less is called a

Answer 32

tropical storm or depression.

Question 33

used to rank hurricanes based on their wind speed. Note how wind speed is related to the level of air pressure within the eye of a hurricane and its associated storm surge.

Answer 33

Saffir Simpson scale

Question 34

rapid rise in sea level called a ________ that inundates
areas above the normal high tide line (up to ___ rise in
sea level)

Answer 34

storm surge
9 m

Question 35

commonly leads to inland flooding far from where a storm makes landfall.

Answer 35

Intense precipitation

Question 36

the primary source of energy for tropical cyclones

Answer 36

ocean

Question 37

In addition to a storm’s precipitation rate, another key factor affecting the level of
flooding is a __________ as it moves over land. Slow moving storms

Answer 37

storm’s forward speed

Question 38

Slow-moving storms less than
___________

Answer 38

(16 km/ hr)

Question 39

Slow moving storm is particularly more dangerous since ________________

Answer 39

more rain will fall on a
given area compared to a storm that passes more rapidly .

Question 40

Rainfall intensity will also increase
when an ocean storm moves inland and encounters____________________

Answer 40

rugged or mountainous terrain

Question 41

The rapid elevation gain results in faster cooling rates, which, in turn, increases
the __________________

Answer 41

condensation and precipitation rates.

Question 42

The oldest mitigation strategy goes back to ancient cultures, where they___________________

Answer 42

avoided locating large settlements directly on the coasts

Question 43

the use of radio technology by ocean-going ships in the early 1900s to report weather conditions back to land-based stations.

Answer 43

Development of early warning systems

Question 44

combined with aircraft data allow scientists to use computer models to predict the path of hurricanes with
impressive accuracy.

Answer 44

weather satellites continuously track the storms’ location

Question 45

can now commonly predict out to 48 hours in advance where a hurricane
will make landfall and do so with a fairly high degree of accuracy.

Answer 45

Forecasting models

Question 46

which allows wave energy to pass beneath the structure rather
than smashing it completely off its foundation.

Answer 46

elevate a building above the
expected storm surge level

Question 47

These are unusually high-energy waves that form not from the wind, but rather by the transfer of energy from earthquakes, volcanic eruptions, landslides, or asteroids to a body of water.

Answer 47

Tsunamis

Question 48

Tsunamis traveling through deep ocean waters have exceptionally long wavelengths, typically from___________, and their wave base can be rather deep.

Answer 48

(10 - 500 km)

Question 49

Tsunamis travel at speeds of over _____________

Answer 49

(800 km/ hr ).

Question 50

December 26, 2004, wherein a magnitude 9.1 earthquake
occurred in the subduction zone located off the Indonesian coast of Sumatra which caused the______________

Answer 50

seafloor to suddenly shift

Question 51

passing tsunami waves are detected
based on their unusually long wavelength and high velocity.

Answer 51

deep ocean buoys

Question 52

are strong currents that flow away from the shore, sometimes inappropriately referred to as a

Answer 52

rip tide.

Question 53

Is a physical barrier made of concrete, steel, or large rocks built against the
shore. It is also called a bulkhead or revetment.

Answer 53

Seawall

Question 54

Often referred to as
hard stabilization or “armoring a shoreline” because it
physically prevents waves from directly impacting the shoreline.

Answer 54

Seawall

Question 55

made of large rocks or steel sheets and is built perpendicular to the shore.

Answer 55

groin

Question 56

refers to a group of groins.

Answer 56

groin field

Question 57

built-in perpendicular
to the shore in order to trap sand
moving with the longshore
current.

Answer 57

Groins

Question 58

barriers made of large rocks and are installed at the mouth of an
inlet to keep sediment from longshore current to clog channels,
thereby reducing dredging costs.

Answer 58

Jetties

Question 59

normally come in pairs
and are placed at the mouth
of inlets to help keep the
longshore movement of sand
from clogging navigational
channels.

Answer 59

Jetties

Question 60

barrier placed just offshore and is used to keep waves from
directly impacting the shoreline.

Answer 60

breakwater

Question 61

In many cases, the only real solution to beach starvation is to manually add
sand to the beach in a process called

Answer 61

beach nourishment.