Coastal Landscape Development

What is a wave-cut platform?

a flat or gently sloping surface formed by wave erosion at the base of a sea cliff

What is undercutting?

when powerful destructive waves erode the base of a cliff, usually at high tide, creating a notch

What is wave refraction?

the bending of waves as they approach a headland, concentrating wave energy onto the headland

What is a stack?

a tall, vertical column of rock formed by erosion of a headland that stands isolated from the coast

What is the sequence of erosional landform formation of a stump?

1. crack

2. cave

3. arch

4. stack

5. stump

Which two types of erosion mainly widen joints to form caves?

• hydraulic action

• abrasion

What is the most common depositional coastal landform?

a beach

Why/How do spits form?

the coastline changes direction and waves lose energy so sediment is deposited

What is a tombolo?

a bar of sediment connecting an island to the mainland or another island formed by deposition

Why is the area behind spits and barrier beaches very sheltered?

tidal currents and river currents meet at the area behind spits and barrier beaches, causing high levels of deposition, which can lead to the formation of salt marshes

What is eustatic change?

a global change in sea level relative to the land caused by changes in the volume of water in the oceans due to factors such as ocean temperature or the amount of water stored in ice sheets

What is isostatic change?

a local change where land height changes relative to sea level, often due to the removal or addition of weight such as ice sheets

What are the three main causes of eustatic change?

• changes in the amount of ice

• thermal expansion of sea water

• tectonic changes to ocean basins

How does the rate of isostatic change compare with the rate of eustatic change?

isostatic change usually occurs more slowly than eustatic change

What is isostatic recovery?

the process where land rises after the melting of heavy ice sheets that previously depressed it

What are emergent landforms?

coastal features formed when sea level falls or land rises

What is a ria?

a submerged river valley formed when rising sea levels flood the lower course of a river valley

How do fjords compare with rias in depth?

fjords are typically deeper than rias because they were carved by glaciers

What is a Dalmatian coast?

a submergent coastline where parallel valleys are flooded, forming long narrow islands parallel to the coast

According to the Intergovernmental Panel on Climate Change (IPCC), what is the predicted range of sea level rise by 2100?

between 0.3m and 1.0m higher than current levels