Geography AS Unit 2 Crowded Coasts

Question 1

Define eustatic and isostatic

Answer 1

Eustatic - sea level change caused by change in volume of water in sea or ocean basis - tectonic movements/climate change
Isostatic - sea level change caused by vertical movements of land relative to sea

Question 2

Impacts of sea level change

Answer 2

more frequent + severe coastal flooding
submergence of low-lying islands
changes in coastline

Question 3

4 options for coastal management

Answer 3

1. hold the line - maintain defence
2. advance the line - build new coastal defences further out to the sea
3. do nothing - build no coastal defences
4. retreat the line - build no coastal defence, but move people away from coast

Question 4

Hard engineering

Answer 4

sea wall - expenisve build and maintain, reflects waves, creates strong backwash =erode under wall
groynes - cheap, fences built at angle, trap beach material and transport by ls drigt = wide beach = slower waves/damaged by stores
gabions - cheap, absorb wave energy, ugly

Question 5

Soft engineering

Answer 5

beach nourishment - food added to beach, wide beach = reduce erosion
dune regeneration - sand dunes created or restored, batter/absorb wave energy

Question 6

Waves

Answer 6

constructive - low frequency, low+long, elliptical cross profile, powerful swash = carries beach material and deposits it, weak backwash
destructive - high frequency, high+steep, circular cross profile, strong backwash weak swash = removes material