Edexcel A-level Geography - Coasts
1970 Bhola Cyclone - ANS - - 300,000 were killed
- $90 million economic loss
- Improved warning systems, embankments and cyclone shelter network saves many lives.
\Abrasion - ANS - - Sediment within wave is thrown against rock. This is repeated and rock is
chipped away.
- High energy waves with a larger height have more energy so increase rates of erosion through
abrasion
- Sedimentary rock eroded most quickly by abrasion
\Accretion - ANS - - Building up of land
- Due to net deposition at sink regions occurring in sediment cells
- Leads to a fall in local sea level
\Advance the Line - ANS - - Build new coastal defences on the seaward side of the existing
coastline.
- Usually this involves land reclamation.
\Advantages of Hard Engineering (2) - ANS - - Obvious to "at risk" people that something is
being done
- A 'one-off' solution that could protect a coastline for decades
\Advantages of Soft Engineering (3) - ANS - - Cheap
- Sustainable
- Aesthetically pleasing
\Agricultural Land Value - ANS - £21,000 per ha
\Amenity value - ANS - Value in cultural, human well-being and economic terms of an attractive
environment people enjoy using
\Angle of Wave Attack (Sediment Transportation) - ANS - - Main determinant of sediment
transportation
- Sediment transported in the direction of the wind blowing towards the beach
- Backwash transports sediment perpendicular down the beach
\Anticyclones - ANS - Produce gentle winds and small waves = low rates of recession
\Aswan Dam, River Nile - ANS - - Constructed in 1964
- Reduced volume from 130 million tonnes p.a. to 15 million tonnes p.a.
- Erosion increased from 20 meters per year to 200 meters per year
- River Delta starved of sediment
\Attrition - ANS - - Sediment within a wave collides and is broken down into smaller particles.
This process is repeated.
- Occurs in foreshore and nearshore zones, where sediment is moved by swash and backwash
- Soft rocks are broken down quickly and split into sand particles
\Average island height Maldives - ANS - 1.5 metres above sea level
\Backshore - ANS - The area above the high tide mark, affected by wave action only during
major storm events.
,\Bangladesh flooding - ANS - In November 2007, cyclone Sidr brought storm surges of up to 6m
high to Bangladesh, as well as heavy rain and strong winds, resulting in significant flooding
across the land
\Bangladesh relief stat - ANS - 60% of Bangladesh is less than three metres above sea level
\Bars/Barrier Beaches - ANS - - Linear ridges of sand/shingle extending across a bay and are
connected to land on both sides.
- Traps a body of seawater behind it, forming a lagoon.
- Form when LSD extends a spit across the entire width of the bay.
\Beach Morphology - ANS - Shape of the Beach
\Beach nourishment - ANS - - Artificially replacing sediment lost by erosion or to enlarge the
beach
- Costs £20 million per km
- Has to be done frequently
- Sediment can't be sourced from elsewhere in the same sediment cell
\Beach sediment profile - ANS - Pattern of distribution of different sized or shaped deposited
material.
\Beaches - ANS - - Accumulations of sand and shingle found in the foreshore and backshore
zones.
- Produced by material being deposited by constructive waves
- Swash has energy to carry material up the beach
- Weak backwash only has energy to carry finest sediment down the beach, leaving the
remaining material up the beach
\Bedding Plane - ANS - Surface separating layers of strata.
\Benefits of Erosion - Happisburgh - ANS - By 2105, between 20 and 35 houses would be
'saved' from erosion, with a combined value of £4 million - 7 million
45 hectares of farmland would be saved, with a value of £945,000
The Manor Caravan Park would be saved, which employs local people.
\Biological Weathering - ANS - Break down of rock in situ by living or once-living organisms
\Blockfall - ANS - - Occurs on slopes >40', where a rock fragment breaks away and either drops
vertically or bounces downslope.
- Very rapid, taking only a few seconds to occur.
\Business Land Value - ANS - £500,000 per ha
\Capital of Maldives - ANS - Malé
\Carbonation - ANS - - Rainwater mixed with carbon dioxide from the air to form weak carbonic
acid (pH 5.6).
- The acidic rain mixes with calcium carbonate to form soluble calcium bicarbonate solution.
- 'Rock disappears' as minerals dissolve into a solution.
\Cave - Arch - Stack - Stump - ANS - - Rock eroded by hydraulic erosion due to joints and faults.
Widening of these weak points forms a cave.
- Eventually, marine erosion will cause the cave to break through to the other side of the
headland forming an arch
, - Hydraulic action and abrasion attack the sides of the arch between low tide and high tide,
forming wave cut notches.
- Overhang eventually collapses by mass movement due to gravity. This widens the arch.
- Weathering and other sub-aerial processes attack the arch roof. Eventually the roof collapses
due to block fall leaving a stack.
- Marine erosion attacks the stack forming a notch until the stack collapses due to block fall.
- Causes a stump to form (small projection of rock exposed at low tide)
\Central government stakeholders of Odisha - ANS - Archaeology Department of Culture
Water Resource Department
\Chemical Weathering - ANS - Chemical reactions attack individual minerals in the rock,
breaking bonds and producing new chemical compounds.
\Classifying Coasts - Advancing/Retreating - ANS - - Classified as Advancing/Retreating due to
processes
- Long Term Processes = Emergent/Submergent Coastline
- Short Term Processes = Eroding/Outbuilding Coastline
\Classifying Coasts - Energy Inputs (5) - ANS - - Used to classify High/Low Energy Coastlines
- Waves (Main Input)
- Tides (Moon's Gravitational Pull)
- Currents
- Rivers
\Classifying Coasts - Geology - ANS - - Characteristics of land, including lithology (rock type)
and structure (arrangement of rock units).
- Used to classify coasts as cliffed, sandy, estuarine, concordant and discordant
\Classifying Coasts - Long Term Criteria (2) - ANS - - Geology
- Sea Level Change
\Classifying Coasts - Sea Level Change - ANS - - Used to Classify Coasts as Emergent or
Submergent
- Caused by eustatic/isostatic changes
- Caused by climate change
\Classifying Coasts - Sediment Inputs - ANS - - Sediment is added through deposition and
removed through erosion
- Sediment Inputs received by waves and wind, tides, currents, mass movement and tectonic
processes
\Classifying Coasts - Short Term Criteria (3) - ANS - - Energy Inputs
- Sediment Inputs
- Advancing/Retreating
\Clastic rocks - ANS - Made of sediment particles cemented together
\Cliff profile - ANS - The height and angle of a cliff face as well as its features, such as wave-cut
notches or changes in slope angle.
\Cliff Stabilisation - ANS - - Cliff slope angles reduced to increase stability and re-vegetated to
reduce surface erosion.
- In-cliff drainage reduces pore-water pressure and mass movement risk
- Costs of £1 million per 100 meters
\Cliffed Coastline (4) - ANS - - High energy environment
1970 Bhola Cyclone - ANS - - 300,000 were killed
- $90 million economic loss
- Improved warning systems, embankments and cyclone shelter network saves many lives.
\Abrasion - ANS - - Sediment within wave is thrown against rock. This is repeated and rock is
chipped away.
- High energy waves with a larger height have more energy so increase rates of erosion through
abrasion
- Sedimentary rock eroded most quickly by abrasion
\Accretion - ANS - - Building up of land
- Due to net deposition at sink regions occurring in sediment cells
- Leads to a fall in local sea level
\Advance the Line - ANS - - Build new coastal defences on the seaward side of the existing
coastline.
- Usually this involves land reclamation.
\Advantages of Hard Engineering (2) - ANS - - Obvious to "at risk" people that something is
being done
- A 'one-off' solution that could protect a coastline for decades
\Advantages of Soft Engineering (3) - ANS - - Cheap
- Sustainable
- Aesthetically pleasing
\Agricultural Land Value - ANS - £21,000 per ha
\Amenity value - ANS - Value in cultural, human well-being and economic terms of an attractive
environment people enjoy using
\Angle of Wave Attack (Sediment Transportation) - ANS - - Main determinant of sediment
transportation
- Sediment transported in the direction of the wind blowing towards the beach
- Backwash transports sediment perpendicular down the beach
\Anticyclones - ANS - Produce gentle winds and small waves = low rates of recession
\Aswan Dam, River Nile - ANS - - Constructed in 1964
- Reduced volume from 130 million tonnes p.a. to 15 million tonnes p.a.
- Erosion increased from 20 meters per year to 200 meters per year
- River Delta starved of sediment
\Attrition - ANS - - Sediment within a wave collides and is broken down into smaller particles.
This process is repeated.
- Occurs in foreshore and nearshore zones, where sediment is moved by swash and backwash
- Soft rocks are broken down quickly and split into sand particles
\Average island height Maldives - ANS - 1.5 metres above sea level
\Backshore - ANS - The area above the high tide mark, affected by wave action only during
major storm events.
,\Bangladesh flooding - ANS - In November 2007, cyclone Sidr brought storm surges of up to 6m
high to Bangladesh, as well as heavy rain and strong winds, resulting in significant flooding
across the land
\Bangladesh relief stat - ANS - 60% of Bangladesh is less than three metres above sea level
\Bars/Barrier Beaches - ANS - - Linear ridges of sand/shingle extending across a bay and are
connected to land on both sides.
- Traps a body of seawater behind it, forming a lagoon.
- Form when LSD extends a spit across the entire width of the bay.
\Beach Morphology - ANS - Shape of the Beach
\Beach nourishment - ANS - - Artificially replacing sediment lost by erosion or to enlarge the
beach
- Costs £20 million per km
- Has to be done frequently
- Sediment can't be sourced from elsewhere in the same sediment cell
\Beach sediment profile - ANS - Pattern of distribution of different sized or shaped deposited
material.
\Beaches - ANS - - Accumulations of sand and shingle found in the foreshore and backshore
zones.
- Produced by material being deposited by constructive waves
- Swash has energy to carry material up the beach
- Weak backwash only has energy to carry finest sediment down the beach, leaving the
remaining material up the beach
\Bedding Plane - ANS - Surface separating layers of strata.
\Benefits of Erosion - Happisburgh - ANS - By 2105, between 20 and 35 houses would be
'saved' from erosion, with a combined value of £4 million - 7 million
45 hectares of farmland would be saved, with a value of £945,000
The Manor Caravan Park would be saved, which employs local people.
\Biological Weathering - ANS - Break down of rock in situ by living or once-living organisms
\Blockfall - ANS - - Occurs on slopes >40', where a rock fragment breaks away and either drops
vertically or bounces downslope.
- Very rapid, taking only a few seconds to occur.
\Business Land Value - ANS - £500,000 per ha
\Capital of Maldives - ANS - Malé
\Carbonation - ANS - - Rainwater mixed with carbon dioxide from the air to form weak carbonic
acid (pH 5.6).
- The acidic rain mixes with calcium carbonate to form soluble calcium bicarbonate solution.
- 'Rock disappears' as minerals dissolve into a solution.
\Cave - Arch - Stack - Stump - ANS - - Rock eroded by hydraulic erosion due to joints and faults.
Widening of these weak points forms a cave.
- Eventually, marine erosion will cause the cave to break through to the other side of the
headland forming an arch
, - Hydraulic action and abrasion attack the sides of the arch between low tide and high tide,
forming wave cut notches.
- Overhang eventually collapses by mass movement due to gravity. This widens the arch.
- Weathering and other sub-aerial processes attack the arch roof. Eventually the roof collapses
due to block fall leaving a stack.
- Marine erosion attacks the stack forming a notch until the stack collapses due to block fall.
- Causes a stump to form (small projection of rock exposed at low tide)
\Central government stakeholders of Odisha - ANS - Archaeology Department of Culture
Water Resource Department
\Chemical Weathering - ANS - Chemical reactions attack individual minerals in the rock,
breaking bonds and producing new chemical compounds.
\Classifying Coasts - Advancing/Retreating - ANS - - Classified as Advancing/Retreating due to
processes
- Long Term Processes = Emergent/Submergent Coastline
- Short Term Processes = Eroding/Outbuilding Coastline
\Classifying Coasts - Energy Inputs (5) - ANS - - Used to classify High/Low Energy Coastlines
- Waves (Main Input)
- Tides (Moon's Gravitational Pull)
- Currents
- Rivers
\Classifying Coasts - Geology - ANS - - Characteristics of land, including lithology (rock type)
and structure (arrangement of rock units).
- Used to classify coasts as cliffed, sandy, estuarine, concordant and discordant
\Classifying Coasts - Long Term Criteria (2) - ANS - - Geology
- Sea Level Change
\Classifying Coasts - Sea Level Change - ANS - - Used to Classify Coasts as Emergent or
Submergent
- Caused by eustatic/isostatic changes
- Caused by climate change
\Classifying Coasts - Sediment Inputs - ANS - - Sediment is added through deposition and
removed through erosion
- Sediment Inputs received by waves and wind, tides, currents, mass movement and tectonic
processes
\Classifying Coasts - Short Term Criteria (3) - ANS - - Energy Inputs
- Sediment Inputs
- Advancing/Retreating
\Clastic rocks - ANS - Made of sediment particles cemented together
\Cliff profile - ANS - The height and angle of a cliff face as well as its features, such as wave-cut
notches or changes in slope angle.
\Cliff Stabilisation - ANS - - Cliff slope angles reduced to increase stability and re-vegetated to
reduce surface erosion.
- In-cliff drainage reduces pore-water pressure and mass movement risk
- Costs of £1 million per 100 meters
\Cliffed Coastline (4) - ANS - - High energy environment
