costal ecosystems - coastal flooding

Question 1

what are the causes of flooding?

Answer 1

1. abnormal high tides

2. tsunamis

Question 2

what areas are most affected by flooding ?

Answer 2

1. low-lying coastal areas (Maldive Island)

2. subsiding areas (Venice)

Question 3

how can the risk of flooding be reduced

and info:

Answer 3

1. prediction (where, when, scale, likelihood of damage and health) .
2. prevention ( build defences, construct emergency centres, instal high warning systems, educate local people)

Question 4

definition of a coastal cell:

Answer 4

it is very hard to protect the coast if you look at it in one big piece. but if you look at it in small sections and spread each are into coastal cells its easier.

Question 5

definition and difference of soft and hard engineering:

Answer 5

soft engineering: tries to stop the forces of nature, but working with (absorbing wave energy/tidal energy)
hard engineering: to stop the forces of nature by working against the power of the waves.

Question 6

what is managed retreat?

and the advantages and disadvantages of it:

Answer 6

this is another type of coastal management, it involves abandoning existing coastal defences and allowing the sea to invade that space until it reaches higher land. allowing low- lying areas to flood and turn into salt marshes.

the advantages: formation of salt marshes create a new home to animals, and it makes a natural protection defence.

Question 7

name hard engineering techniques and their advantages and disadvantages.

Answer 7

1. RECURVED SEA WALLS - adv. protects houses and life behind it.
   - it reflects the energy back into the sea because of its recurved shape.
   disadv. - expensive, restricts access to beaches.
2. GROYNES - adv. beaches build up, which then act as a natural defence against erosion.
   disadv. doesnt look that nice, and builds up sand unnaturally.
3. RIP RAP- adv. absorb wave energy and protect weak cliffs behind. look quite natural.
   disadv. expensive, till let some energy through, restrict access.

Question 8

name soft engineering techniques and their advantages and disadvantages.

Answer 8

1. BEACH REPLENISHMENT - adv. looks natural, provides beach for tourists, quite cheap.
   - disadv. sea keeps eroding it away, has to be replaced every few years.
2. FENCING / HEDGING / REPLANTING VEGETATION
   adv. preserves beaches and sand dunes, reduces amount of sand blown inland
   disadv. fencing may look ugly / fencing might rust