-Coasts 1.a
Coastline: bit and land affected by each other (37 miles inland, 200 miles
offshore). A dynamic zone where land and sea overlap and interact.
The system includes terrestrial (rock type/structure, earthquakes),
anthropogenic (climate energy, sea defences, civilisation, industry),
marine (tides, wave type/strength) and atmospheric (tides, wind
strength/direction/duration- fetch/precipitation).
Open system- transfers energy and matter across boundaries (closed-
only energy). Costal (open).
Outputs: evaporation, wind erosion
Inputs: thermal, kinetic, potential, material (material deposition,
weathering, mass movement form cliffs)
Stores: sediments, beaches
Transfers: long shore drift
Dynamic equilibrium- equilibrium disrupted so system self regulates to
counteract, this is negative feedback.
Sediments are from: rivers, cliffs, seabed, erosion of depositional
features, aeolian process (wind)
Sediments ends up: spits/bars/tombolo, sand dunes, salt marshes
Sediment cell- coastline where movement of material is self-contained
divided into sub cells and councils manage them. 11 in UK.
-Coasts 1.b
What affects the coastal system:
Wind-
Movement of air flowing from high to low pressure, reaching
equilibrium. Winds are strong when there is a pressure gradient
during storms.
Waves-
Wave energy: H= 0.36 square root F (h= wave height, f =fetch)
Standard deviation: σ= √(∑ (X - X̄)^2)/ n (σ= standard
deviation, ∑= sum of, X= each value in data set, X̄= mean of all
values, n= number of values in data set.)
Their potential energy is reliant of the distance above the trough.
Contain kinetic energy caused by motion of water within the wave.
, Waves move in circles. A wave is caused by friction of wind and sea
surface.
Powerful waves are from fast, long duration wind with a long fetch.
Wave refraction: direction of a traveling wave is changed due to the
interaction with the ocean's bottom topography.
Constructive: strong swash weak backwash
Destructive: strong backwash
Waves are the same however some have different behaviours due to
shape of sea floor and coast.
Types of breaking waves:
1. Plunging (moderately steep onto steep beaches. Water plunges
vertically downwards as the crest curls over)
2. Spilling (steep onto gently slopping beaches. Water spills, and
spreads)
3. Surging (low onto steep beaches. Slides forward and might not
break)
Tides-
Tides are the periodic rise and fall of the ocean surface, caused by
the gravitational pull of the moon and sun. To put it into perspective,
stretches the top and bottom waters of the earth.
Tidal range: difference between high and low tides at a specific
location.
Talbot Bay in Australia West Coast, can rise by 36 feet, making it one
of the largest tidal changes in the world.
Spring tides are when the sun moon and earth are aligned therefore
large tidal range. A neap tide is when the moon and sun are at right
angles therefore low tidal range. Twice a month.
An amphidromic point has 0 tidal fluctuation.
Closed areas (Mediterranean) low tidal range. Funnelled areas
(Severn estuary) high tidal range.
A tidal bore is the leading edge of the incoming tide forms a wave of
water that travels up a river against the direction of the rivers
current.
Geology-
Lithography: physical and chemical characteristics of rock(s) in an
area.
Structure: properties of rock such as jointing, bedding, faulting and
permeability.
Concordant rocks: when the rock outcrops are uniform, they tend to
produce straight coastlines.
Coastline: bit and land affected by each other (37 miles inland, 200 miles
offshore). A dynamic zone where land and sea overlap and interact.
The system includes terrestrial (rock type/structure, earthquakes),
anthropogenic (climate energy, sea defences, civilisation, industry),
marine (tides, wave type/strength) and atmospheric (tides, wind
strength/direction/duration- fetch/precipitation).
Open system- transfers energy and matter across boundaries (closed-
only energy). Costal (open).
Outputs: evaporation, wind erosion
Inputs: thermal, kinetic, potential, material (material deposition,
weathering, mass movement form cliffs)
Stores: sediments, beaches
Transfers: long shore drift
Dynamic equilibrium- equilibrium disrupted so system self regulates to
counteract, this is negative feedback.
Sediments are from: rivers, cliffs, seabed, erosion of depositional
features, aeolian process (wind)
Sediments ends up: spits/bars/tombolo, sand dunes, salt marshes
Sediment cell- coastline where movement of material is self-contained
divided into sub cells and councils manage them. 11 in UK.
-Coasts 1.b
What affects the coastal system:
Wind-
Movement of air flowing from high to low pressure, reaching
equilibrium. Winds are strong when there is a pressure gradient
during storms.
Waves-
Wave energy: H= 0.36 square root F (h= wave height, f =fetch)
Standard deviation: σ= √(∑ (X - X̄)^2)/ n (σ= standard
deviation, ∑= sum of, X= each value in data set, X̄= mean of all
values, n= number of values in data set.)
Their potential energy is reliant of the distance above the trough.
Contain kinetic energy caused by motion of water within the wave.
, Waves move in circles. A wave is caused by friction of wind and sea
surface.
Powerful waves are from fast, long duration wind with a long fetch.
Wave refraction: direction of a traveling wave is changed due to the
interaction with the ocean's bottom topography.
Constructive: strong swash weak backwash
Destructive: strong backwash
Waves are the same however some have different behaviours due to
shape of sea floor and coast.
Types of breaking waves:
1. Plunging (moderately steep onto steep beaches. Water plunges
vertically downwards as the crest curls over)
2. Spilling (steep onto gently slopping beaches. Water spills, and
spreads)
3. Surging (low onto steep beaches. Slides forward and might not
break)
Tides-
Tides are the periodic rise and fall of the ocean surface, caused by
the gravitational pull of the moon and sun. To put it into perspective,
stretches the top and bottom waters of the earth.
Tidal range: difference between high and low tides at a specific
location.
Talbot Bay in Australia West Coast, can rise by 36 feet, making it one
of the largest tidal changes in the world.
Spring tides are when the sun moon and earth are aligned therefore
large tidal range. A neap tide is when the moon and sun are at right
angles therefore low tidal range. Twice a month.
An amphidromic point has 0 tidal fluctuation.
Closed areas (Mediterranean) low tidal range. Funnelled areas
(Severn estuary) high tidal range.
A tidal bore is the leading edge of the incoming tide forms a wave of
water that travels up a river against the direction of the rivers
current.
Geology-
Lithography: physical and chemical characteristics of rock(s) in an
area.
Structure: properties of rock such as jointing, bedding, faulting and
permeability.
Concordant rocks: when the rock outcrops are uniform, they tend to
produce straight coastlines.
