Coasts (Cambridge (CIE) IGCSE Geography)

A berm is a ridge of sand and shingle formed at the top of a beach by storm waves.

Wave refraction is the bending of waves as they approach the shore at an angle, causing them to become more parallel to the coastline.

A wave-cut platform is a flat or gently sloping surface formed by wave erosion at the base of a sea cliff.

A headland is a high point of land that projects out into the sea, usually made of more resistant rock.

False.

Bays are formed in areas of less resistant rock that erode more quickly than the surrounding harder rock.

A discordant coastline is where bands of different rock types run perpendicular to the coast.

A stack is an isolated pillar of rock standing in the sea, formed when a sea arch collapses.

A spit is a depositional feature with a long, narrow build-up of sand or shingle projecting from the land into the sea, often with a curved or hooked end.

A tombolo is a bar of sand or shingle linking an island to the mainland or another island.

A lagoon is a shallow body of water that has a sand bar, coral reef, or other barrier separating it from the sea.

False.

Sand dunes can also form in coastal areas where there is a supply of sand and onshore winds.

A barrier island is a long, narrow island of sand parallel to the mainland coast, separated from it by a lagoon or bay.

Succession is the process of change in the species structure of an ecological community over time as different plants colonise a sand dune environment.

Pioneer species are the first plants to colonise a new sand dune environment, such as marram grass, which can tolerate harsh coastal conditions.

A coral polyp is a small, soft-bodied organism that secretes a hard, protective limestone skeleton, which forms the structure of coral reefs.

Zooxanthellae are microscopic algae that live symbiotically within coral tissues, providing food through photosynthesis and contributing to coral colour.

False.

Coral reefs cannot tolerate water temperatures below 18°C and grow best at 22°C–25°C.

A fringing reef is a coral reef that grows close to and parallel to the shoreline of an island or continent.

A barrier reef is a coral reef separated from a mainland or island shore by a deep lagoon.

An atoll is a ring-shaped coral reef, island, or series of islets enclosing a lagoon.

A halophyte is a salt-tolerant plant that grows in soil or waters of high salinity.

A salt marsh is a coastal ecosystem in the upper coastal intertidal zone between land and open salt water or brackish water that is regularly flooded by the tides.

False.

While mainly found in tropical waters, some mangroves have adapted to more temperate conditions.

Prop roots are specialised aerial roots that grow from the trunk and branches of some mangrove trees, helping to support the tree in soft sediments.

The intertidal zone is the area that is above water at low tide and under water at high tide.

Snorkel roots are specialised roots in some mangrove species that stick out of the mud to help the tree take in air in oxygen-poor soils.

A storm surge is a rapid rise in sea level caused by really low-pressure storms.

A storm tide is a combination of high tide and low-pressure storm.

False.

Tsunamis are large sea waves due to underwater earthquakes.

A king tide is an exceptionally high tide that occurs when the gravitational pull of the sun and moon align.

Coastal squeeze is the loss of coastal habitats due to rising sea levels and human-made coastal defences preventing natural landward migration.

A hurricane is a type of tropical storm that forms in the tropical North Atlantic Ocean and Northeast Pacific.

False.

Tropical storms form in both the northern and southern hemispheres.

A submergent coastline is a coastline that has experienced a relative rise in sea level, leading to flooding of former land areas.

An emergent coastline is a coastline that has experienced a relative fall in sea level, exposing former sea floor.

Coastal erosion is the wearing away of land and the removal of beach or dune sediments by wave action, tidal currents, wave currents, drainage, or high winds.

Integrated Coastal Zone Management (ICZM) is an approach that aims to use a combination of methods to best reflect all stakeholders' needs in coastal management.

Soft engineering is a coastal management approach that works with natural processes rather than against them, usually cheaper and less damaging to the appearance of the coast.

False.

While hard engineering can be more effective in some cases, it is not always more effective than soft engineering and can have negative impacts.

Beach replenishment is the process of pumping or dumping sand and shingle back onto a beach to replace eroded material.

Managed retreat is a coastal management strategy where existing coastal defences are abandoned, allowing the sea to flood inland until it reaches higher land or a new line of defences.

A sea wall is a hard-engineered structure, usually made of concrete and curved outward to deflect the power of waves.

Groynes are wooden, rock or steel structures built at right angles to the shore. They trap beach material and prevent it being moved by longshore drift.

Gabions are wire cages filled with stone, concrete, or sand and used for coastal protection.

False.

Shoreline Management Plans (SMP) set out approaches to managing a coastline from both flooding and erosional risk.

Hold the line is a coastal management approach where defences are built and maintained to keep the current position of the shoreline the same.

Advance the line is a coastal management strategy that involves building new defences to extend the existing shoreline, often through land reclamation.

Do nothing is a coastal management approach where no investment is made in protecting the coastline or defending against flooding, regardless of any previous intervention.