Sea level change

Question 1

What is sea level change due to? (Sea coasts)

Answer 1

Either eustatic or isostatic change

Question 2

What is eustatic change? (Sea coasts)

Answer 2

The rise and fall in sea level

Question 3

What are the characteristics of eustatic change? (Sea coasts)

Answer 3

• Effects are always global
• Decrease temperature means more precipitation falls as snow
• This increases the volume of water stored in glaciers, reducing volume of water in the sea
• Increased temperature melts the ice sheets

Question 4

What is isostatic change? (Sea coasts)

Answer 4

The land rising relative to the sea level rise. Any downward movement of the land causes the sea level to rise

Question 5

What are the characteristics of isostatic change? (Sea coasts)

Answer 5

• Effects are always local
• Caused by vertical movements in the land
• Subsidence of land due to shrinkage from draining marshland can lead to isostatic change

Question 6

What are the impacts of sea level change? (Sea coasts)

Answer 6

• frequent coastal flooding
• low lying islands
• changes in coastline

Question 7

What is the impact of more frequent coastal flooding, with examples? (Sea coasts)

Answer 7

Flooding of low lying land has increased due to sea level rise

e.g St Marks square, Venice has flooded 100 times since 1996

Question 8

What is the impact of low lying islands, with examples? (Sea coasts)

Answer 8

They have disappeared completely due to sea level rise

e.g Maldives, if there is a 0.5m rise they will disappear

Question 9

What is the impact of changes to the coastline, with examples? (Sea coasts)

Answer 9

Coastline changes and islands are created. The area of land decreases

e.g Britian’s separation from mainland Europe

Question 10

What are the features of a coastline of submergence? (Sea coasts)

Answer 10

RIA’s
Fjords
Dalmatian coastline

Question 11

What are RIA’s? (Sea coasts)

Answer 11

• Formed when river valleys have been partially submerged
• Long and cross profile
• Wide/deep at the mouth and become narrow/shallow further inland

Question 12

What are fjords? (Sea coasts)

Answer 12

• Drowned glacier valleys
• Straight and narrow
• Steep sides
• Shallow mouth and deeper inland

Question 13

What are dalmatian coastlines? (Sea coasts)

Answer 13

• Areas where valleys lie parallel to the coast
• Form from increase in sea level
• Valleys flood, leaving islands

Question 14

What are the features of an emergence coastline? (Sea coasts)

Answer 14

• Raised beaches
• Abandoned coastline
• Slope over wall cliff

Question 15

What are raised beaches? (Sea coasts)

Answer 15

• Formed when fall in sea level exposes wave cut platforms
• Over time beech sediment becomes vegetated
• Develops into soil

Question 16

What are abandoned coastlines? (Sea coasts)

Answer 16

• Cliffs raised above beaches are no longer eroded by the sea
• Slowly covered in vegetation
• Gradually weather over time

Question 17

What is a slope over wall cliff? (Sea coasts)

Answer 17

• The result of combined sea fall and sea rise
• Formed in periglacial conditions
• Erosion at the base forming the vertical cliff