Variations In Coastal Processes Landforms And Landscapes Over Different Timescales

Question 1

Examples of changes in seconds

Answer 1

High energy storm events

Rapid mass movement

Question 2

Effects of high energy storm events

Answer 2

Causes an increase in wave energy, resulting in increases in erosion and transportation

Removal of large amounts of beach sediment- changes beach profile
Destruction or breaching of sand dunes
Coastal flooding

Question 3

Effects of rapid mass movement

Answer 3

Rockfalls, landslides, slumps create changes in cliff face profile and retreating cliffs, with loss of land and possibly buildings

Question 4

What are the seasonal changes in summer? 5

Answer 4

Fewer storms
Less frequent high speed winds
Lower energy waves
Waves predominantly constructive
Sediment moves onshore, building up beach, increasing gradient of upper beach and forming a berm

Question 5

What are the seasonal changes to the beach in winter? 5

Answer 5

More storms 
High winds more frequent
Higher energy waves
Destructive waves more frequent 
Sediment moves offshore, lowering beach profile, creates a steeper upper beach and gentler lower beach

Question 6

What is eustatic change?

Answer 6

Global change in the volume of water in the oceans.
Sea level falls during glaciation period as water Is frozen.
Global warming of climate increases temperature, melts continental ice sheets, adds water to oceans and raises sea levels.
Warmer oceans means expanding water volume, sea level rises

Question 7

What is isostatic change?

Answer 7

Localised change in relative sea level caused by up or down movement of land masses.
During glacial periods, ice weight causes land to sink.
Melting ice removes the weight and the land slowly rises (isostatic recovery) leads to relative fall in sea level

Question 8

Impact of rising sea levels

Answer 8

Rising sea levels flood lower parts of the coast
Deltas spits and beaches disappear underwater or due to increased erosion
River flood plains and valleys flood to form a broad river estuary called a ria (kingsbridge estuary Devon)
If it’s U shaped it forms a fjord which is very deep and flat bottomed (sognefjord Norway 1.3km deep)

Question 9

Impacts of falling sea levels

Answer 9

Beaches are no longer affected by waves, forms raised beaches.
Cliff line and landforms left stranded as relict cliffs.
The wave cut platform forms a marine terrace and can be used for agriculture.
Western coast of Scotland (isostatic recovery is 2mm a year)