Coasts KQ3- How do coastal landscapes evolve over time? Flashcards Preview

OCR A level Geography > Coasts KQ3- How do coastal landscapes evolve over time? > Flashcards

Flashcards in Coasts KQ3- How do coastal landscapes evolve over time? Deck (12):
1

Give examples of change which occurs over 10s of years

-mass movement
-human impact
-beach sediment moved

2

Give examples of change which occurs over 100s of years

-spits and barrier islands formed
-cliff landslides
-salt marsh development

3

Give examples of change which occurs over 1000s of years

-changing sea level
-arches and stacks
-straightening of coastlines

4

Give examples of change which occurs over millions of years

-change in relative position of land and sea

5

What is Eustatic sea level change?

-worldwide fall or rise of sea level
-absolute change in volume stored in oceans

6

Why might sea levels fall eustatically?

-reduction in temperatures
-more water is stored in solid form
-ice ages

7

Why might sea levels rise eustatically?

-glaciers/ice melt due to increase in global temperatures

8

What is isostatic sea level change?

Local changes in sea level resulting from land falling or rising relative to the sea

9

Why might sea levels fall isostatically?

-melting of ice sheets releases pressure on land underneath
-so land rises (isostatic recovery)

10

Why might sea levels rise isostatically?

-ice sheets thicken
-weight of ice causes land to lower

11

Why is Scotland rising whereas the South of England is sinking?

Scotland had thicker ice sheets than the South so is recovering more than the south of England

12

Why are sea levels rising currently?

1- Air temperature increasing, water in ocean is warmed which results in thermal expansion
2- Ice sheets and glaciers melt