Coastal flooding Flashcards
What local factors affect coastal flooding?
Height
Low pressure
Natural subsidence
Vegetation removal
Why is Netherlands at high risk of coastal flooding? (Physical and Human)
Physical
Low lying (26% below SL)
Subsidence of 8mm
High tides
Low pressure zone (mid latitude depressions)
Human
70% of GDP at risk
How have the Netherlands managed risk from flooding?
Delta werks
Built floating houses
Flooded farmland to relocate water (They saved over 940,000 acres of land)
Polders - draining delta swamps into nearby rivers
Built 9km in storm surge barriers
Use water to pump turbines and windmills
How has flooding impacted people in the Netherlands?
50,000 buildings damaged
1 billion dollars lost
Eustatic sea level rise
Temp rise, water particles expand, thermal expansion
Ice melts, water rises
Eustatic sea level fall
Evaporated water gets locked up as ice during glacial period
Isostatic sea level rise
Ice forms, land is compressed, sea level rises (emergent)
Ice melts, sediment is deposited, crustal sag and delta subsidence
What is the physical risk in Louisiana?
Subsidence
Accretion
Tectonic uplift
Sea level rise (isostatic)
What is the human impacts in Louisiana?
New year stock exchange
Flooding of subways
Loss of energy
What human actions are increasing coastal flooding?
Groundwater extraction is increasing
The weight of building is increasing subsidence
Environmental determinism
How does the physical environment control a society or states ability to develop
Why is climate change putting Kiribati at risk?
Eustatic sea level rise
Isostatic sea level rise
Coral bleaching
Salt water intrusion
What do corals provide?
Diverse ecosystems
Food
Protect shorelines from erosion
What is eustatic sea level rise causing in Kiribati?
Higher sea surface temperatures, thermal expansion
Bwabwai crop is unable to be grown
Coral bleaching
Environmental refugees
Refugees caused by environmental disasters
Maldives coastal risk
Low lying 1m above sea level
Storm surges
SLR
600,000 tourists each year
What is accretion?
The accumulation of material
How does height affect coastal flooding?
Storm surges (short term sea level rise) sea level rise (long term)
Bangladesh is 3m above sea level
Maldives is 2.3m above sea level
Tarwaha (kiribati) is 3m above sea level
Maldives main risks of coastal flooding
Low lying
Mangrove deforestation
Bangladesh main coastal risks of flooding
Low lying 3m above sea level
Funnel shaped topography
Intense rainfall
Sea level rise
Storm surges increasing coastal flooding
Low pressure zone
High speed winds
Increase the impact of destructive waves
High tides
Sea level rise temporary
Storms/Depressions
Areas of low pressure
They create high speed winds
Increases SLR
Delta
They are formed when rivers unload sediment into them
Maldives risk
3m above sea level
97% risk of sea level rise
Affected by storm surges
Not enough finance for management
Bangladesh coastal risk
Funnel shape
Low lying 2.3m
Unconsolidated sediment
Isostatic rebound
Mangrove deforestation
Ganges river system
Bangladesh coastal response
Raising embankments above sea level
25 cyclone shelters
Improved resilience and training
Reduced flooding from 20 days to 5 days
Slow progress
How much economically was lost in the Netherlands flooding?
16 million
-2% GDP
30% fall in house prices
Why are people in the Netherlands vulnerable?
17.4 million
At risk of sea level rise
Subsidence of 8mm per year
Storms
