Sea Level Change

Question 1

What were sea levels like 18000 years ago? Why?

Answer 1

Sea levels were 120m lower than today.

This is because of glaciation up until 18000 years ago, since then, glaciation has taken place.

Question 2

Define and explain eustatic change with reference to the two components of it

Answer 2

Eustatic change is the world wide change in sea level caused by changes in world climate. A rise in global temperature causes a rise in world sea levels.
Two components -melting ice sheets
-thermal expansion (1’c = 80cm rise)

Question 3

Define and explain isostatic change

Answer 3

This is the change in land level relative to the sea due to tectonic activity and isostatic rebound.

Question 4

Describe the isostatic change going on in the U.K. currently

Answer 4

Scotland rising 3mm

Essex sinking 3mm

Question 5

What does submergent mean?

Answer 5

Where the sea is rising, relative to the land

Question 6

What does emergent mean?

Answer 6

Where the land is rising, relative to the sea

Question 7

What are submergent and emergent landforms?

Answer 7

Flooded river valley - rias or drowned estuaries
Flooded glacial valleys - fjords or lochs
Raised beaches, raised stacks stumps and arches, mainly coastlines of rapid marine erosion with cliffs and wavecut platforms, relict cliffs