Coasts Flashcards
What is the rate of erosion on the Holderness coast?
On average 2m/yr
What is the Holderness Coast’s lithology?
Boulder clay
Examples of coastal protection on the Holderness Coast
Hornsea - sea wall, rock armour, groynes
Mappleton - cost £1.9 million
Withernsea
Why does the Holderness Coast erode so much?
Large fetch
Powerful destructive waves are common
Sea floor is relatively deep meaning waves reach the cliffs of it jour being weakened by friction
What is the spit called on the Holderness Coast?
Spurn Head
Why is Bangladesh at risk of flooding?
Worlds most densely populated country
46% of the population lives less than 10m above sea level
Mangrove forest is retreating by 200m annually due to erosion
Bay of Bengal concentrates storms
Why is the Maldives at risk of coastal flooding?
Highest point is 2.3m above sea level
Hallsands, Devon
Dredged leaving no beach
A storm in 1917 ruined the whole village
Deltawerkwen, Netherlands
Hard engineering project
Cost $5 billion
A series of dams aiming to reduce risk of flooding
Greenland ice sheet
Since 1990 it has contributed a 1/3 of sea level rise
7.4m sea level rise if it all melts
How long are marram grass roots?
3m long
Impact of a dam on the River Nile?
130 million tonnes -> 15 million tonnes (sediment volume)
How much does steric sea level rise account for?
75%
How much does water expand by when frozen?
9%
Sea level rise in Kiribati
Many of its islands could disappear in 50 years
Rising by 1.2m/yr (4x the global average)
Impact on food security
Contaminating groundwater sources
