Edexcel GCSE Geography B (1GB0) — UK Physical Landscapes
Every time a new sea wall is poured, the local beach is fundamentally altered. Human actions modify coastal landscapes in two main ways: through direct and indirect impacts. A direct impact happens immediately at the site of human activity, whereas an indirect impact is a secondary consequence, often occurring further away or as part of a global shift.
Direct impacts involve physical alterations to the landform itself. Hard engineering strategies, such as building groynes or rip-rap, are designed to halt natural processes but permanently change the coastline's shape. Urbanisation also directly affects cliffs; constructing residential buildings adds massive weight pressure to fragile rock structures, making them prone to collapse. Furthermore, roads and pavements do not allow water to pass through; these impermeable surfaces force rainwater to flow overland as surface runoff rather than soaking into the ground naturally.
In contrast, indirect impacts trigger wider, systematic changes across larger geographical scales. Anthropogenic change, such as human-driven climate change, causes thermal expansion of the oceans, raising UK sea levels by 12–16cm since 1900. This increased water volume leads to coastal squeeze, where natural habitats like saltmarshes are trapped and destroyed between rising tides and fixed sea defences. Offshore dredging for construction materials also indirectly damages the coast by removing vital sediment from the system, leaving shorelines vulnerable to wave attack.
When evaluating these impacts for an assessment, direct interventions have intense, highly localised effects that are easier to monitor. However, indirect impacts like climate change possess the greatest significance for overall landscape change. They alter the baseline water level for the entire global coastline, magnify the energy of destructive waves, and threaten the long-term viability of coastal communities far more than any single local development.
The coastline of England and Wales is not one continuous stretch, but rather divided into 11 distinct, invisible recycling zones. A is a self-contained stretch of coastline where sand and shingle are circulated. These cells operate in a state of , meaning the amount of material entering the system naturally balances the amount leaving over time.
Within a cell, sediment moves from sources (eroding cliffs) via transfers (like longshore drift) to sinks (areas of deposition like spits). Human interference frequently disrupts this natural balance. If a town builds groynes to trap sand, it prevents longshore drift from carrying material further down the coast. This leads to terminal groyne syndrome, where beaches downdrift are completely starved of protective sand, exposing the bare cliffs to accelerated marine erosion.
We can measure this disruption using a sediment budget, which calculates the balance of material in the cell. If outputs exceed inputs, the budget becomes negative, and the coastline retreats.
Calculate the sediment budget for a coastal cell over one year using the hypothetical data provided.
Step 1: Identify the inputs (sources) and outputs (sinks/losses).
Step 2: State the sediment budget equation.
Step 3: Substitute the values and calculate.
Why are entire villages tumbling into the North Sea on the east coast of England? The Holderness Coast is retreating at an average of 2 metres per year, making it the fastest-eroding coastline in Europe. This rapid change is driven by a complex interaction between harsh physical marine processes and human management decisions.
The physical baseline of Holderness is highly vulnerable. The coastline is composed of soft boulder clay left behind by ancient glaciers, offering very little resistance to the powerful waves generated over the long fetch of the North Sea. However, human intervention has dramatically altered exactly where and how fast this erosion happens.
At Mappleton, £2 million was spent installing rock groynes to protect the village and a vital coastal road. While successful locally, these groynes trapped sediment and blocked the natural transfer of sand. This triggered severe terminal groyne syndrome further south at Great Cowden. Without a protective beach to absorb wave energy, destructive waves directly undercut the cliff base. Gravity then pulled the unsupported clay down through mass movement, specifically slumping. Consequently, erosion rates at Great Cowden surged from 2.5m to 3.8m per year, proving that human engineering often merely shifts the physical problem down the coast.
Can simply paving a driveway cause a cliff to collapse? At Barton-on-Sea in Christchurch Bay, the interaction between coastal urbanisation and local geology demonstrates exactly how human development accelerates natural decay. The cliffs here are geologically unstable, featuring permeable sands sitting directly on top of impermeable clay layers.
When residential areas and roads are built on the cliff top, they add massive physical weight to the weak rock structure. Additionally, they cover the ground in impermeable concrete and tarmac. Rainwater cannot infiltrate the earth naturally, leading to rapid surface runoff that is channelled heavily into the cliff face.
Instead of draining away safely, this excess water pools at the boundary between the sand and clay layers, drastically increasing pore water pressure. This internal fluid pressure, combined with the extra weight of the buildings above, triggers massive rotational slumping. This causal chain perfectly illustrates how a direct human impact (urban development) interacts with physical weathering processes to permanently alter a coastal landscape.
Students often describe 'pollution' (like plastic waste) as a direct impact on the coast. However, in physical geography, you must focus on how human actions alter the physical landforms and geological processes (like erosion and longshore drift).
For an 'Assess' question on human impacts, examiners expect a concluding judgement. Always clearly state which factor (direct or indirect) has the greatest significance for landscape change overall.
When explaining case studies like Holderness or Christchurch Bay, ensure you distinguish between marine processes (like longshore drift) and sub-aerial processes (like slumping or weathering). Both interact, but they occur in different parts of the cliff system.
If you are asked to calculate a sediment budget, remember that a negative figure always indicates a deficit, meaning the coastline is likely to retreat due to a lack of protective sediment.
Direct impact
A change to the coastal landscape that occurs as an immediate, primary result of human activity at a specific location, such as building a sea wall.
Indirect impact
A secondary, often larger-scale consequence of human activity that alters global systems, which in turn affect the coast, such as climate change causing sea-level rise.
Hard engineering
The use of man-made, solid structures such as sea walls and groynes to control natural processes.
Groynes
Low walls or barriers built out from a beach into the sea to check erosion and drifting.
Surface runoff
Water that flows over the land surface rather than soaking into the ground, often increased by impermeable urban surfaces.
Anthropogenic change
Environmental change caused or influenced by people, either directly or indirectly.
Thermal expansion
The increase in volume of ocean water as it warms, which contributes to global sea-level rise.
Coastal squeeze
The loss of natural habitats, such as saltmarshes, as they are trapped between rising sea levels and fixed human structures like sea defences.
Sediment cell
A largely self-contained section of the coastline where the movement of sand and shingle is in a state of dynamic equilibrium.
Dynamic equilibrium
A state of balance within a coastal system where the inputs of sediment naturally equal the outputs over time.
Transfers
The movement of sediment from one part of a coastal system to another (e.g., via waves or currents).
Longshore drift
The zig-zag movement of sediment along a coastline caused by waves approaching at an angle.
Sinks
Areas within a sediment cell where deposition is the dominant process, such as spits or beaches.
Terminal groyne syndrome
Accelerated coastal erosion occurring downdrift from the final groyne in a series, caused by the interruption of natural longshore drift.
Sediment budget
The balance between the amount of sediment entering a sediment cell (inputs) and leaving it (outputs).
Boulder clay
A structurally weak, soft rock composed of clay, sand, and stones deposited by glaciers.
Mass movement
The downhill movement of rock and soil under the force of gravity, including processes such as rotational slumping.
Slumping
A specific type of mass movement where material moves down a slope with a rotational motion.
Pore water pressure
The outward pressure exerted by water trapped within the gaps of rock or soil, which can destabilise cliffs.
Put your knowledge into practice — try past paper questions for Geography B
Direct impact
A change to the coastal landscape that occurs as an immediate, primary result of human activity at a specific location, such as building a sea wall.
Indirect impact
A secondary, often larger-scale consequence of human activity that alters global systems, which in turn affect the coast, such as climate change causing sea-level rise.
Hard engineering
The use of man-made, solid structures such as sea walls and groynes to control natural processes.
Groynes
Low walls or barriers built out from a beach into the sea to check erosion and drifting.
Surface runoff
Water that flows over the land surface rather than soaking into the ground, often increased by impermeable urban surfaces.
Anthropogenic change
Environmental change caused or influenced by people, either directly or indirectly.
Thermal expansion
The increase in volume of ocean water as it warms, which contributes to global sea-level rise.
Coastal squeeze
The loss of natural habitats, such as saltmarshes, as they are trapped between rising sea levels and fixed human structures like sea defences.
Sediment cell
A largely self-contained section of the coastline where the movement of sand and shingle is in a state of dynamic equilibrium.
Dynamic equilibrium
A state of balance within a coastal system where the inputs of sediment naturally equal the outputs over time.
Transfers
The movement of sediment from one part of a coastal system to another (e.g., via waves or currents).
Longshore drift
The zig-zag movement of sediment along a coastline caused by waves approaching at an angle.
Sinks
Areas within a sediment cell where deposition is the dominant process, such as spits or beaches.
Terminal groyne syndrome
Accelerated coastal erosion occurring downdrift from the final groyne in a series, caused by the interruption of natural longshore drift.
Sediment budget
The balance between the amount of sediment entering a sediment cell (inputs) and leaving it (outputs).
Boulder clay
A structurally weak, soft rock composed of clay, sand, and stones deposited by glaciers.
Mass movement
The downhill movement of rock and soil under the force of gravity, including processes such as rotational slumping.
Slumping
A specific type of mass movement where material moves down a slope with a rotational motion.
Pore water pressure
The outward pressure exerted by water trapped within the gaps of rock or soil, which can destabilise cliffs.
