Term
COASTAL TOPOGRAPHY IS GREATLY INFLUNCED BY WHAT FORCE ?
The U.S East coast and Canadian arctic coast are tectonically __________.
the west coasts of the U.S is tectonically active because they are close to ____________.
in tectonically active regions, mountain building leads to what two land features? |
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Definition
Plate tectonics
Passive
transform boundaries
sea cliffs , Rocky shorelines |
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Term
coastlines in temperate regions are influenced by ___________ vegetation, and subtropical and tropical shores are affected by the growth of ________ and ___________.
how much of the U.S population is near the coasts |
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Definition
marsh
mangroves
offshore coral reefs
53 % |
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Term
| what are the 4 most serious types of coastal hazards |
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Definition
strong coastal currents
coastal erosion
storm surge
tsunamis |
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Term
what gives waves their energy?
can this enrgy originate thousands of kilomiters from shore Y/N |
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Definition
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Term
| what three factors dictate how l;arge a wave is ? |
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Definition
velocity of wave speed
Duration of wind
distance that the wind blows across the water surface |
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Term
as waves move away from their place of origin, they become sorted out into__________ or _________ of waves that have _________ sizes and shapes.
a type of wave that arrives unexpectedly on shore is called ____________
what are the 3 parameters to decribe wave height? |
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Definition
groups
sets
similiar
rogue waves
wave height, wave length, wave period |
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Term
| if i were thrown into the ocean with a life vest what type of motion will move me around? |
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Definition
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Term
| the shape of orbital motions change as waves enter __________ water, at a depth of less than _____ their wavelength, the waves begin to ____________. |
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Definition
shallow
one half
feel bottom |
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Term
far out the waves generasted by storms are named _______.
these waves as they near the shoreline become _______ and break on shore.
what is means of predicting when a storm will reach the shore |
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Definition
swells
unstable
by measuring velocity/height of distant storm waves |
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Term
| wave energy is also approximately proportional to the ______________ of the wavelegnth. a wave that is 2 meters will increase by a factor of ___________. |
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Definition
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Term
| when a wave enters a coastal zone only the wave periods remain, but what are the 3 other events to occur |
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Definition
shape / movement change
wavelegnth / velocity decrease
waveheight increases |
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Term
the most dramatic features of waves entering shallow water is their _____________ in height.
the wave crest becomes unstable when the water depth is apprx __________ times the wave height. Why does this happen at this point. |
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Definition
dramatic increase
1.3
cant maintain symmetrical form |
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Term
wave height may increase or decrease as they near shore, and the varoations are caused by irregualr variations in the ____________ topography and by chnages in the _________ of the coastline.
irregular coastlines have small rocky peninsulas known as ________. what 2 shapes are these?
as water comes into contact with headlands they slow down and bend, and this is called __________ |
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Definition
offshore
shape
headlands
straight or curved
refraction |
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Term
where are the largest waves found on a shoreline?
the long term effect of greater energy expendenture on protruding areas, such as headlands, is that wave erosion ___________ the shoreline |
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Definition
along a rocky headland
straitens |
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Term
| waves which plunge are known as ____________. these typically form on steep beaches and tend to be more __________. waves that spill are refereed to as ____________. can the types of breakers which hit shore never change seasonally Y/N. |
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Definition
plunging breakers
spilling breakers
No, the seasons have an effect |
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Term
what are the 2 materials which make up beaches ? and what causes these materials to accumulate?
on islands in the pacific what material causes the beachs to be white? on hawaiis black sand beachs? and in carolina brown brown sand beachs? |
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Definition
sand , gravel
wave action
sheel coral bits
fragments of volcanic rock
quartz feldspar |
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Term
cliffs along the sea are called ____________ and cliffs along lakes are refered to as ___________.
berms are flat bachshore areas formed by deposition of sediment as waves __________ and _____________ the last of their energy.
the part of the beach which experienced backwash and uprush of waves is called what ? |
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Definition
sea cliffs
bluffs
rush up
expend
swash zones |
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Term
portion of nearshore environment where turbulant translational waves move toward the shore afteer the incoming waveas break is defined as _________?
what is beyond the surf zone?, and this is the area where waves become unstable, peak, and break.
a sand bar is also called a ________, and forms bneath each line of breakers in the ____________.
how are longshore troughs formed? |
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Definition
the surf zone
breaker zone
longshore bar
breaker zone
wave and current action |
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Term
is sand on the beach static T/F ?
when a storm occurs what force returns the sand to the beach ?
longshore drift refers to the transport of sediment by ocean currents that flow essentially ____________ to the shoreline.
what is the primary mechanisim for littoral transport? and what is the general direction of littoral transport? |
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Definition
False, waves constantly keep snad moving
sea waves
parellel
longshore currents
south |
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Term
what two factors influence relative sea level ?
eustatic sea level is controlled by processes that affect the overall _________ of water in the ocean and the shape of ____________.
what affects both the average sea temnperature as well as the amount of water stored as ice?
what changes the shape of oceanic basins ? |
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Definition
movement of land and water
volume
ocean basins
ocean basins
temperature
tectonic processes |
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Term
coastlines which are tectonically active are strongly/less strongly influenced by eustatic sea level.
movement of shoreline is also influneced by the rate of three things along the coast.
what from space effects the tides
changes in wind speed also do what to oceans? how does this process affect sea level? |
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Definition
less strongly
deposition, erosion, and subsidence
gravitational pull of the moon and sun
influence sea levels
high winds pile up water |
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Term
are coastline hazards a risk to all shorelines ? but what is a universal hazards?
strong near shorwe currents can develop on any coast with _____.
strong astronomical tides can produce strong currents in what two land features ?
low lying islands in the pacific called atolls are in danger of what? |
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Definition
no
coastal erosion
breaking waves
narrow bays and channels
being inundated |
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Term
strong coastal currents can be produced by what two processes.
powerful currents which can carry large amounts of water away from the shore are known as __________. how do these develop? |
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Definition
back flow of water in the surf zone
rising / falling of the tide.
rip currents
large waves pile up between longshore bar and the sswash zone. |
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Term
most input of sediment is caused by ____________ that move the sediment along ____________ or by_______________ erosion.
erosion of what coastal features add sediment to beachs?
output of sediment occurs when coastal processes move sand or gravel _____________ from the beach, and may include __________, and____________ eroding sand |
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Definition
coastal processes
the shore
local wave
sand dunes or cliffs
away
littoral drift
onshore winds |
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Term
a sea cliff or bluff is vulnerable to what 2 natural processes?
erosion by plunging breakers during storms cause many sea cliffs and lakeshore bluffs to ____________.
what helps protects the cliff from wave erosion during periods between storms? |
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Definition
wave action
running water
retreat
beach sediment |
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Term
urbanization causes extras runoff which ______________ slopes and water must be drained or _____________ to avoid slope failure.
human structures also add _____________ to slopes further weakening them. |
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Definition
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Term
what system can record severall thousand elevation measurements each second with a vertical resolution of 6 inches ?
what 2 factor effects the rate of erosion along coasts |
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Definition
LIDAR
resistance of earth materails
energy of waves |
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Term
| coastal processes are linked to what 8 natural hazrds? |
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Definition
| earthquakes, volcanic eruptions, tsunamis, cyclones, flooding, landslides, subsidence, and climatic change |
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Term
wave erosion at the base of a sea cliff and lakeside bluffs undercuts the slope and frquently produces ____________.
for many beaches coastal erosion is the only signifigant input of what material ?
longshore drift maintain ________ beachs and ___________. |
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Definition
landslides
sand
sandy
lakeshores |
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Term
barrier islands are seperated from the mainland by a _________ or _________.
dunes act as a natural barrier against _____________ and partially protect ____________. |
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Definition
lagoon
Bay
storm waves
structures |
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Term
construction of inlet jetties interferes with what?
modification of coastal zones has led to ______________ x more erosion to coastal areas. much of it is caused what 4 human structures? |
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Definition
natural southward movement of sand
30/40
groundwater,petroleum withdrawel, damming of rivers, coastal engineering structures |
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Term
army engineer measuremnts since 1860 have shown showed that lake michigan fluctuated by how many feet.
severity of ersosion on a particluar siate depends on what 4 factors? |
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Definition
6.5 feet
coastal dunes, orientation of the coastline, groundwater seepage, existance of protective structureres. |
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Term
what are the 2 approachs to minimize beach erosion? and briefly explain.
seawalls are structures built on land parrellel to the coastline to help ______________ erosion and protect ____________ from damage.
constructing a sea wall may not be effective as a result of what 2 reasons? |
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Definition
Hard stabalization: structures to protect a shoreline
soft stabalization : adding sand to beachs
retard
structures
erosion by land and water |
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Term
name this structure which is placec perpendicular to shore?, and when in groups are called?
each one of these is desighned to __________ a portion of sand from __________.
an inherent problem with these structurex is that erosion occurs__________ of the structures because the longshore drift has been ____________ of sand. |
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Definition
groins
groin field
trap
longshore drift
downdrift
depleted |
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Term
the process that requires extracting sand from the ocean flooe and placing it on the beach is defined as ?
what is the name of the structre which is desghned to intercept waves and provide protected areas for a harbor.
this structure is desghned to keep a ship or boat channel open in a fixed location, with minimal dredging to remove sedimnet. |
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Definition
beach nourishment
breakwater
jetties |
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Term
jeties block ___________, causing the ipdrift beach adjacent to one jetty to widen whereas downdrift beachs erode.
beach nouishment is the artificial process of ________.
what are the 3 ways to deal with coastal erosion? |
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Definition
littoral transport
puitting sand on the beach |
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