Coastal Landscapes in the UK

What is the coast?

The coast is the area where land meets the sea or ocean. It is a transitional zone that is influenced by both land and sea processes with distinctive physical features.

Coasts can take a variety of forms, depending on the local geology, climate, and sea/ocean conditions. Some coasts are characterised by steep cliffs and rocky shores, while others have sandy beaches and dunes. Some coasts are sheltered and calm, while others are exposed to strong waves and currents.

The coast is an important ecological and economic resource, providing habitats for a wide range of species, as well as supporting a range of human activities, such as fishing, tourism, and shipping. However, the coast is also vulnerable to a range of natural and human-induced threats, such as sea-level rise, erosion, pollution, and overdevelopment.

To manage and protect the coast, many countries and areas have developed coastal management plans and policies, which aim to balance the needs of different stakeholders and promote sustainable use of coastal resources. These plans often involve a range of measures, such as beach nourishment, habitat restoration, and zoning regulations, to help protect the coast and minimise the impacts of coastal development and other activities.

What are constructive and destructive waves?

Constructive and destructive waves are two types of ocean waves that have different effects on the coastline

Constructive waves are typically low-energy waves that have a long wavelength and a low height-to-length ratio. They tend to approach the shore at an angle and break gently, depositing sediment and building up the beach. Constructive waves are important for building and maintaining beaches, and they are often associated with calm weather conditions.

Destructive waves, on the other hand, are high-energy waves that have a short wavelength and a high height-to-length ratio. They tend to approach the shore more directly and break forcefully, eroding sediment and potentially causing damage to coastal structures. Destructive waves are often associated with stormy weather conditions and can have a significant impact on the coastal environment.

What are the main processes at the coast?

The main processes at the coast are a combination of physical, chemical, and biological processes that shape the land. These processes can vary depending on the specific type of coast, but some of the most important processes include:

Erosion: this is the process by which waves and currents remove sediment from the shore, cliffs, or dunes. It can be caused by a range of factors, including storms, tides, and sea-level rise.

Transportation: Material is moved along the coast by water and wind. The main form of transportation is longshore drift

Deposition: is where sediment is deposited along the coast. This can occur when waves and currents lose energy, or when sediment is carried by rivers and deposited at the coast.

Weathering: Weathering is the process by which rocks and other materials are broken down by physical and chemical processes. 

Mass movement: The downhill movement of material under the influence of gravity

These processes can interact with each other in complex ways, leading to changes in the shape and form of the coast over time. Understanding these processes is important for managing and protecting the coast, as well as for predicting and adapting to the impacts of climate change and other environmental pressures.

What are the processes of coastal erosion?

Coastal erosion is the process by which waves and currents remove sediment from the shore, cliffs, or dunes. There are several processes that can contribute to coastal erosion, including:

Hydraulic action: This is the process by which waves exert pressure on rocks and cliffs, leading to erosion. The force of the water can break off pieces of rock and cause the cliff face to become unstable.

Abrasion: the process by which sediment is removed from the coast by the action of waves carrying sediment and other debris, which can cause erosion of the shoreline or cliffs.

Corrosion: is also known as solution, is the process by which waves and currents dissolve soluble rocks, such as limestone or chalk, and carry the dissolved material away, leading to erosion.

Attrition: This is the process by which sediment on the coast is worn down and broken up into smaller pieces by the action of waves and currents, leading to erosion and loss of sediment.

These processes can interact with each other, leading to complex erosion patterns and changes in the shape and form of the coast over time. Coastal erosion can have significant environmental, economic, and social impacts, such as loss of habitat, damage to infrastructure, and increased risk of flooding and storm damage.

Which coastal landforms are the result of erosion?

Coastal erosion can create a variety of landforms, which are shaped by the processes of erosion and deposition. Some of the most common coastal erosion landforms include:

• Headlands and bays occur where there are alternating bands of hard and soft rocks run perpendicular to oncoming waves (discordant coastline). At first, the soft rock (e.g. clay) is eroded backward, forming an inlet. As the inlet continues to erode it curves inwards, and a bay is formed, usually with a beach. The hard rock (e.g. limestone) is left protruding out to sea as a headland

Cliffs and wave cut platforms. Cliffs are steep rock faces that are formed by the erosion of coastal rock by waves and other processes leaving a wave cut platform as the cliff retreats. Cliffs can be vulnerable to erosion and collapse, especially in areas with high rates of erosion.

Caves, arches, and stacks:The formation of stacks begins with the erosion of a coastal cliff by waves, which can gradually wear away the softer rock, such as sandstone or shale, leaving harder rock, such as limestone or granite, standing in place. Over time, this erosion can create small sea caves and arches in the cliff face.As these caves and arches continue to erode, they can become larger and eventually connect through the cliff, creating a natural tunnel. When the roof of the tunnel collapses due to erosion, a stack is formed. The stack is then further eroded by the waves, which can cause it to become narrower and taller, eventually creating a tall, slender pillar.

What is longshore drift?

Longshore drift is a process by which waves and currents move sediment along the shore in a zigzag pattern. 

Longshore drift occurs when waves approach the shore at an angle. As the waves break, they cause the water and sediment to move up the beach at an angle. When the water and sediment flow back down the beach, it is pulled by gravity straight down the slope of the beach, resulting in a net movement of sediment in a direction parallel to the shore. This process is repeated with each wave, causing sediment to move along the beach in a zigzag pattern.

Which coastal landforms are the result of deposition?

Spits, tombolos, and bars are all types of coastal landforms that are formed by the movement of sediment along the shore. Each of these landforms is created by a different process, but they all involve the accumulation of sediment in a particular shape.

A spit is a long, narrow stretch of sand which extends from the mainland out into the sea. Spits are usually formed by longshore drift.. As sediment is carried along the coast by the waves, it can accumulate in a particular location, often at a bend or change in the coastline. Over time, the sediment builds up to form a long, narrow spit that is connected to the mainland at one end.

A tombolo is a type of sandbar that connects an island to the mainland. Tombolos are formed when sediment is deposited by waves and currents in a particular location, such as at the end of an island.

A bar is a type of sandbar that forms offshore, parallel to the shoreline. Bars are formed by the movement of sediment by waves and currents, which can cause the sediment to accumulate in a particular location.