Coastal Systems & Landscapes
1. Geo CSL coasts as a system & coastal zones
Storm Beach - A beach affected by particularly fierce waves, with a very
long fetch
Wave refraction - The bending of waves
Why does wave refraction happen? - When the water becomes shallower
at a point on a coastline
What is an isolated system? - Has no interactions with anything outside
the system. No inputs of energy or matter. Many controlled lab
experiments are this type but they're very rare in nature
What is a closed system? - Have inputs and outputs of energy but not
matter
What is an open system? - Ones where there are inputs and outputs of
energy and matter across the boundary, most ecosystems are open
Littoral zone - The area of land between cliffs/dunes & offshore area,
covered by the sea at different times
What short term factors affect the littoral zone? - Tides and storm surges
What long term factors affect the littoral zone? - Changes in sea level and
human intervention
Offshore - Where waves have no influence on the sea level
Inshore - Areva between offshore and LWM
Low Water Mark (LWM) - The area reached by the sea at low tide
Foreshore - Covered with water when the tide is in?
High water mark (HWM) - The level reached by the sea at high tide
Back shore - The area between HWM and the limit of marine activity, only
reached by waves on very big tides or storms
What is the final zone? - The limit of marine activity
Surf zone (low tide) - The zone between the breaking waves and where
they move up the beach in the swash zone
Swash zone (low tide) - Where a turbulent layer of water washes up the
beach
Dynamic equilibrium - Coasts are constantly changing over time to reach
a state of balance with the processes that determine their form. As the
flows of energy & materials passing through a coastal system vary, the
coast changes to move towards dynamic equilibrium. A balance between
Inputs & outputs
Positive feedback - A move away from equilibrium
Negative feedback - Moving towards equilibrium
Breaker zone - The area where waves approaching the coast begin to
break, usually where the depth is 5-10m
2. Geo CSL wind and waves & constructive and destructive waves & wave
refraction
What determines the size of waves? - Strength, persistence and fetch
Fetch - The distance over which the wave is generated
What creates waves? - Tectonic activity, underwater landslides creating
tsunamis but mostly created by the wind
,Oscillatory wave - While the energy moves forwards, the water particles
have a circular motion
Translatory wave - The water particles move forwards rather than in a
circular motion
Why do waves break? - When they reach shallow water, rotating water
particles can't complete their motion, so frictional drag causes waves to
topple forward and break
How tall are destructive waves? - Over 1m
What is the frequency of constructive waves? - 6-8 per minute
What is the frequency of destructive waves? - 10-14 per minute
Which type of wave has high energy? - Destructive
Discordant coastlines - The bands of rock are perpendicular to the coast
What features does a discordant coastline make coastline make? -
Headlands and bays
Concordant coastlines - The bands do rock are parallel to the coast
What type of features does a concordant coastline make? - Coves
What type of wave has a longer wavelength? - Constructive
Wave period - The time required for one wave to pass a point
Do destructive waves have a long or short wave period? - Short (long is 6-
8 waves per min)
Why type of wave has a stronger swash? - Constructive
What is another fact about destructive waves? - They're most likely to
form a storm beach
What is another fact about constructive waves? - They gradually steepen
the beach profile
What type of wave can carry larger sediment? – Destructive
3. Geo CSL ocean currents & tides
Ocean current - Any more or less permenent or continuous, directed
movemnt of ocean water that flows in an ocean
Long shore current - They arrive at a slight angle & when a wave reaches
the coastline, a burst of energy is released which generates a current,
runs parallel to the coastline
Rip current - A strong, localised & narrow current which moves directly
away from the shore, pushing through the lines of breaking waves
Upwelling - Denser, cooler & nutrient rich water is pushed to the ocean's
surface due to the surface water being pushed away from an area
Tide - The rise and fall of sea levels caused by the combined effect of the
gravitational pull of the moon and sun
Tidal bulges - The moon's gravity pulls the water there, deeper. Due to
inertial forces, the opposite side of the earth has this simultaneously
Tidal range - The vertical distance between high & low tides
How long is the tide cycle? (From 1 tide cycle to the next) - Approx 12
hours 25 mins. 2 tide cycles per day (24 hrs 50 mins)
Spring tide - Once every 14 days, the moon, earth & sun are in alignment
which increases the gravitational pull, causing a spring tide (highest high
tide and lowest low tide, max tidal range)
Neap tide - When the moon and sun are at a right angle and the tidal
range is at its lowest (lowest high tides & highest low tides)
, How long does it take for the moon to orbit earth? - 29 days
What happens at the spring & autumn equinoxes? - The highest and
lowest tides occur due to the boost in the sun's gravitational pull
What does the Coriolis effect cause in the northern hemisphere? -
Deflection to the right
Macrotidal - Tidal range of more than 4m
Mesotidal - Tidal range of 2-4m
Microtidal - Tidal range of less than 2m
Why is tidal range important? - It determines the vertical range of erosion
and deposition
Where does large tidal range occur? - In areas with narrowing areas of sea
water, such as the English Channel where water 'piles up', confined to a
narrow neck
Tidal bores - Sudden rises in the tide & influx of water into a narrowing
channel/estuary can result in a wall of water going up river
Name and describe an example of a tidal bore - River Severn tidal bore-
up to 2.8m & over 30km/h
What's an impact of high tides? - If a high tide & low pressure system
coincide, higher rates of erosion occur
What's the name for the movement of water in open ocean? - Swell
Which bay has the world's greatest tidal range? - The bay of Fundy
between Nova Scotia & New Brunswick in canada
How big is the largest tidal range? - 15.25m
Where has the smallest tidal range? - The Mediterranean sea
How small is the smallest tidal range? - 1cm
What occurred in 1953? - The great storm which occurred during a high
tide
How large was the storm surge in 1953? - 2-3m
4. Geo CSL sediment sources and cells
What are the sources of sediment? - Rivers, cliff erosion, material of
biological origin, blown from inland, longshore drift, brought on shore by
constructive waves
Sediment cell - A length of coastline that's relatively self contained in
terms of the movement of sand and shingle
Coastal sediment budget - The balance between sediment being added to
and removed from the coastal system, that system being defined within
each individual sediment cell
What is a positive budget? What happens? - More material is added than
removed- shoreline builds towards the sea
What is a negative budget? What happens. - More material is removed
than added, shoreline retreats landward
What are the features of a low energy coast? - The wave energy is low,
the rate of deposition exceeds the rate of erosion, typical landforms are
beaches & spits
What are examples of low energy coasts? - Estuaries, inlets, sheltered
bays e.g. Baltic Sea
1. Geo CSL coasts as a system & coastal zones
Storm Beach - A beach affected by particularly fierce waves, with a very
long fetch
Wave refraction - The bending of waves
Why does wave refraction happen? - When the water becomes shallower
at a point on a coastline
What is an isolated system? - Has no interactions with anything outside
the system. No inputs of energy or matter. Many controlled lab
experiments are this type but they're very rare in nature
What is a closed system? - Have inputs and outputs of energy but not
matter
What is an open system? - Ones where there are inputs and outputs of
energy and matter across the boundary, most ecosystems are open
Littoral zone - The area of land between cliffs/dunes & offshore area,
covered by the sea at different times
What short term factors affect the littoral zone? - Tides and storm surges
What long term factors affect the littoral zone? - Changes in sea level and
human intervention
Offshore - Where waves have no influence on the sea level
Inshore - Areva between offshore and LWM
Low Water Mark (LWM) - The area reached by the sea at low tide
Foreshore - Covered with water when the tide is in?
High water mark (HWM) - The level reached by the sea at high tide
Back shore - The area between HWM and the limit of marine activity, only
reached by waves on very big tides or storms
What is the final zone? - The limit of marine activity
Surf zone (low tide) - The zone between the breaking waves and where
they move up the beach in the swash zone
Swash zone (low tide) - Where a turbulent layer of water washes up the
beach
Dynamic equilibrium - Coasts are constantly changing over time to reach
a state of balance with the processes that determine their form. As the
flows of energy & materials passing through a coastal system vary, the
coast changes to move towards dynamic equilibrium. A balance between
Inputs & outputs
Positive feedback - A move away from equilibrium
Negative feedback - Moving towards equilibrium
Breaker zone - The area where waves approaching the coast begin to
break, usually where the depth is 5-10m
2. Geo CSL wind and waves & constructive and destructive waves & wave
refraction
What determines the size of waves? - Strength, persistence and fetch
Fetch - The distance over which the wave is generated
What creates waves? - Tectonic activity, underwater landslides creating
tsunamis but mostly created by the wind
,Oscillatory wave - While the energy moves forwards, the water particles
have a circular motion
Translatory wave - The water particles move forwards rather than in a
circular motion
Why do waves break? - When they reach shallow water, rotating water
particles can't complete their motion, so frictional drag causes waves to
topple forward and break
How tall are destructive waves? - Over 1m
What is the frequency of constructive waves? - 6-8 per minute
What is the frequency of destructive waves? - 10-14 per minute
Which type of wave has high energy? - Destructive
Discordant coastlines - The bands of rock are perpendicular to the coast
What features does a discordant coastline make coastline make? -
Headlands and bays
Concordant coastlines - The bands do rock are parallel to the coast
What type of features does a concordant coastline make? - Coves
What type of wave has a longer wavelength? - Constructive
Wave period - The time required for one wave to pass a point
Do destructive waves have a long or short wave period? - Short (long is 6-
8 waves per min)
Why type of wave has a stronger swash? - Constructive
What is another fact about destructive waves? - They're most likely to
form a storm beach
What is another fact about constructive waves? - They gradually steepen
the beach profile
What type of wave can carry larger sediment? – Destructive
3. Geo CSL ocean currents & tides
Ocean current - Any more or less permenent or continuous, directed
movemnt of ocean water that flows in an ocean
Long shore current - They arrive at a slight angle & when a wave reaches
the coastline, a burst of energy is released which generates a current,
runs parallel to the coastline
Rip current - A strong, localised & narrow current which moves directly
away from the shore, pushing through the lines of breaking waves
Upwelling - Denser, cooler & nutrient rich water is pushed to the ocean's
surface due to the surface water being pushed away from an area
Tide - The rise and fall of sea levels caused by the combined effect of the
gravitational pull of the moon and sun
Tidal bulges - The moon's gravity pulls the water there, deeper. Due to
inertial forces, the opposite side of the earth has this simultaneously
Tidal range - The vertical distance between high & low tides
How long is the tide cycle? (From 1 tide cycle to the next) - Approx 12
hours 25 mins. 2 tide cycles per day (24 hrs 50 mins)
Spring tide - Once every 14 days, the moon, earth & sun are in alignment
which increases the gravitational pull, causing a spring tide (highest high
tide and lowest low tide, max tidal range)
Neap tide - When the moon and sun are at a right angle and the tidal
range is at its lowest (lowest high tides & highest low tides)
, How long does it take for the moon to orbit earth? - 29 days
What happens at the spring & autumn equinoxes? - The highest and
lowest tides occur due to the boost in the sun's gravitational pull
What does the Coriolis effect cause in the northern hemisphere? -
Deflection to the right
Macrotidal - Tidal range of more than 4m
Mesotidal - Tidal range of 2-4m
Microtidal - Tidal range of less than 2m
Why is tidal range important? - It determines the vertical range of erosion
and deposition
Where does large tidal range occur? - In areas with narrowing areas of sea
water, such as the English Channel where water 'piles up', confined to a
narrow neck
Tidal bores - Sudden rises in the tide & influx of water into a narrowing
channel/estuary can result in a wall of water going up river
Name and describe an example of a tidal bore - River Severn tidal bore-
up to 2.8m & over 30km/h
What's an impact of high tides? - If a high tide & low pressure system
coincide, higher rates of erosion occur
What's the name for the movement of water in open ocean? - Swell
Which bay has the world's greatest tidal range? - The bay of Fundy
between Nova Scotia & New Brunswick in canada
How big is the largest tidal range? - 15.25m
Where has the smallest tidal range? - The Mediterranean sea
How small is the smallest tidal range? - 1cm
What occurred in 1953? - The great storm which occurred during a high
tide
How large was the storm surge in 1953? - 2-3m
4. Geo CSL sediment sources and cells
What are the sources of sediment? - Rivers, cliff erosion, material of
biological origin, blown from inland, longshore drift, brought on shore by
constructive waves
Sediment cell - A length of coastline that's relatively self contained in
terms of the movement of sand and shingle
Coastal sediment budget - The balance between sediment being added to
and removed from the coastal system, that system being defined within
each individual sediment cell
What is a positive budget? What happens? - More material is added than
removed- shoreline builds towards the sea
What is a negative budget? What happens. - More material is removed
than added, shoreline retreats landward
What are the features of a low energy coast? - The wave energy is low,
the rate of deposition exceeds the rate of erosion, typical landforms are
beaches & spits
What are examples of low energy coasts? - Estuaries, inlets, sheltered
bays e.g. Baltic Sea
