3.7 - Bangladesh Flashcards
1
Q
How high is Bangladesh?
A
Only 9m high max
Most is only 3m above sea level
2
Q
How fast were cyclone wind speeds in 2007?
A
260 kph
- wind transfers energy to waves, makes them higher
3
Q
What is happening to the Bengal Delta?
A
- Subsiding by 8-18mm/year
- isostatic readjustment
- human interference (dredging + urbanisation)
- crustal sagging
4
Q
What makes Bangladesh physically vulnerable to flooding?
A
- low lying
- coastline consists of unconsolidated delta sediment
- made worse by deforestation of mangrove swamps
- Bay of Bengal is triangular shaped, funnels incoming storm surges, higher surges
- projected SLR of 55cm by 2100, destroys mangroves
5
Q
How much farmland would be lost by a 55cm increase in sea level?
A
40%
6
Q
What human actions are endangering Bangaldesh’s coast?
A
- Mangrove deforestation reduces stability of swamps
- reduces dissipation of wave energy during tropical cyclones
7
Q
How do storm surges occur?
A
- cyclones create localised areas of low pressure
- sea levels rise
1mB fall in pressure = 1cm SLR during surge
8
Q
What is happening to wind speeds?
A
Increasing
- 1970 = 205kph
- 2007 = 260kph
9
Q
What effect will climate change have?
A
- tropical storms will be more common, and violent
- storm surges will be more frequent and higher
10
Q
How many people live along the coast of Bangladesh?
A
- > 20 million
- focussed around Dhaka and Chittagong
11
Q
Why is Chittagong important?
A
- location of Bangladesh’s main port
- large source of GDP
12
Q
How are people in Bangladesh protected against coastal flooding?
A
- early warning system in place
- 5000 volunteers to ensure people are aware of incoming cyclones
- series of coastal embankments constructed in 1960s
- protect against storm surge and floods
- emergency shelters have also been in place
- can serve as evacuation points and schools
13
Q
What is the projected sea level rise?
A
- 55cm
- means that 40% of Bangladesh’s farmland would be lost
- coastal mangroves would also be lost
