Coasts

Question 1

Littoral zone

Answer 1

The wider coastal zone including adjacent land areas and shallow parts of the sea just offshore

Question 2

Cliff profile

Answer 2

The height and angle of a cliff face as well as its features, such as wave-cut notches or changes in slope angle

Question 3

Coastal accretion

Answer 3

The deposition of sediment at the coast and the seaward growth of the coastline, creating new land. If often involves sediment deposition being stabilised by vegetation

Question 4

Dynamic equilibrium

Answer 4

The balanced state of a system when inputs and outputs balance over time. If one element of the system changes because of an outside influence, the internal equilibrium of the system is upset and other components of the system change. By a process of feedback, the system adjusts to the change and the equilibrium is regained

Question 5

Holocene

Answer 5

The geological epoch that began about 12,000 years ago at the end of the last Pleistocene ice age. It’s early stages were marked by large sea level rises of about 35m and a warming interglacial climate

Question 6

Faults

Answer 6

Major fractures in rocks produced by tectonic forces and involving the displacement of rocks on either side of the fault line

Question 7

Unconsolidated sediment

Answer 7

Material such as sand, gravel, clay and silt that has not been compacted and cemented to become sedimentary rock (it has not undergone the process of lithification) and so is loose and easily eroded

Question 8

Pore water pressure

Answer 8

The pressure water experiences at a particular point below the water table due to the weight of water above it

Question 9

Fetch

Answer 9

The uninterrupted distance across water over which a wind blows, and therefore the distance waves have to grow in size

Question 10

Swash

Answer 10

The flow of water up a beach as a wave breaks

Question 11

Backwash

Answer 11

When water runs back down the beach to meet the next incoming wave

Question 12

Beach morphology

Answer 12

The shape of a beach, including its width and slope (the beach profile) and features such as berms, ridges and runnels. It also includes the type of sediment (shingle, sand, mud) found at different locations on the beach

Question 13

Blow hole

Answer 13

Forms when a coastal cave turns upwards and breaks through the flat cliff top. Usually this is because of erosion of especially weak strata or the presence of a fault line

Question 14

Currents

Answer 14

Flows of seawater in a particular direction driven by winds or differences in water density salinity or temperature. Some are almost continuous such as those that form the global thermohaline circulation and others are more sporadic such as long shore currents which some last only a few hours such as rip currents

Question 15

Mass movement

Answer 15

The downslope movement of rock and soil; it is an umbrella term for a wide range of specific movements including landslides rockfall and rotational slides

Question 16

Isostatic change

Answer 16

A local rise or fall in land level

Question 17

Eustatic change

Answer 17

Involves a rise or fall in water level caused by a change in the volume of water. This is a global change affecting all the worlds connected seas and oceans

Question 18

Accretion

Answer 18

This occurs when sediment is added to a landform such as a river delta by deposition. It can build up to form new land allowing a delta to grow out to sea. It tends to be balanced by subsidence caused by the weight of the newly deposited sediment

Question 19

Post-glacial isostatic adjustment

Answer 19

Refers to the uplift experienced by land following the removal of the weight of ice sheets. It is sometimes called post-glacial rebound or post-glacial re-adjustment

Question 20

Ria

Answer 20

A drowned river valley in an unglaciated area caused by sea level rises flooding the river valley making it much wider than would be expected based on the river following into it

Question 21

Barrier islands

Answer 21

Offshore sediment bars usually sand dune covered but unlike spits they are not attached to the coast. They are found between 500m and 30km offshore and can be tens of kilometres long

Question 22

Dredging

Answer 22

Involves scooping or sucking sediment up from the seabed or a river bed usually for construction sand or gravel or to deepen a channel so that large boats can navigate it

Question 23

Dissipation

Answer 23

The term used to describe how the energy of a wave is decreased by friction with beach material during the wave swash up the beach. A wide beach slows waves down and saps their energy so when they break most energy has gone

Question 24

Megaproject

Answer 24

A very expensive technically difficult and usually long term engineering project. Many mega projects have multiple aims and often large environmental impacts

Question 25

Return period

Answer 25

Refers to the frequency of a flood of a particular magnitude

Question 26

Environmental refugees

Answer 26

Communities forced to abandon their home due to natural processes including sudden ones such as landslides or gradual ones such as erosion or rising sea levels

Question 27

Sustainable coastal management

Answer 27

Managing the wider coastal zone in terms of people and their economic livelihoods social and cultural wellbeing and safety from coastal hazards as well as minimising environmental and ecological impacts

Question 28

Conflict

Answer 28

In the context of coastal management conflict means disagreement over how the coast should be protected from threats and which areas should be protected. Conflict often exists between different stakeholders such as residents versus the local council

Question 29

Littoral cells

Answer 29

All coastlines divide up into distinct littoral cells containing sediment sources transport paths and sinks. Each littoral cell is isolated from adjacent cells and can be managed as a holistic unit

Question 30

Outflanking

Answer 30

Occurs when erosion gets behind coastal defences at the point where they stop leading to rapid erosion inland and undermining of defences