coasts stats and examples

how fast does the holderness coastline erode

2 metres/ year

how much does a seawall cost per metre in the UK (range)

£5000-10,000

population of hornsea

8000

how far is the coastline from the main road in mappleton

50m

approx lifespan of groynes

50 years

how much did the recirved sea wall at Withernsea cost

£6.3 million

how many caravan pitches is skipsea losing every year

10

what is ghe population of happisburgh

1400

how much did happisburghs coastal sill realignment strategy cost

£80,000

how many fishing villages in Odisha have been given financial investment form the gov to helkp them become less dependent on coastlines

72

how much capacity do cyclone shelters in odisha have

14,000 people

how large was the test pilot ICZM in Odisha

200km

how much has tourism revenue in odisha increased by since infrastructure was implemented

25%

how many vullages in odisha were benefitted by rip rap put in Pinto

6

when were SMPs first introduced in the UK

1995

how many SMPs are there in England

20

example of no active intervention

happisburgh and winterton in norfolk

example of managed retreat

hemsby

population of hembsy in off season vs peak season

3,200 vs. 25,000

example of a place experiencing a lack of sediment due to upstream defences

hemsby

1300 metres of coastline

hemsby coastal defences

many coastal defences along norfolk coastline, yet hemsby determined as managed retreat

relies on tourism for majority of revenue which would suffer if sea wall implemented

given permission to place large granite rocks at the feet of the cliffs however a lack of available funding (£20 million needed)

local council bought some rocks but they are only being placed along 40 metres of hemsbys 1300m coastline

example of hold the line

bacton gas terminal in norfolk

example of advance the line

palm jumeirah in dubai

what percentage of somerset was underwater during 2013/14 floods

10%

how much did loss of tourism cost somerset in 2013/14

£200 million

how muhc of the maldives would be covered by a sea level rise of 50cm

77%

what percentage fo the maldives GDP relies of biodiversity (incl. tourism, fishing etc.)

89%

how many high rise buildings does hulhumale phase II hvae

16

how many people were displaced in the maldives from the boxing day tsunami

30,000

avg elevation of ther maldives above sea level

1.5 metres

example of a sediment cell

portland bill to selsey bill

example of a ria

kingsbury estuary

example of a fjord

lysefjord in norway

where id the dalmatian coastline

croatia

example of a raised fossil beach

lendalfoot in western scotland

how far back is the lendalfoot raised beach from the current coastline

200m

how raised is the lendalfoot coastline

40m

when was the aswan high dam on the nile constructed

1964

how many tonnes did the aswan high dam reduce sediment volume by

115 million

how much did annual erosion in the nile delta increase by with the aswan high dam

175 metres

how many hectares in the blackwater estuary scheme

4000

example of a discordant coastline and what types of rock it is made up of

dorset - made up of limestone and greensands

average rate of erosion of sedimentary rocks

2-6cm/ year

average rate of erosion of igneous rocks

0.1-0.5cm/year

example of an igneous rock

granite

example of a sedimentary rock

limestone

example of a metamorphic rock

marble

what types of plants do sand dunes have

halophytes and xerophytes

psammosere succcession pattern

embryo, fore, yellow, and grey dunes

whatr type of dunes does marram grass colonise

yellow dunes

what type fo dune does heather normally colonise

grey dune

how frequent are destructive waves

10-15/ minute

grequency of constructive waves

6-9/ minute

example of where river/ coastline dredging has decreased supply of sediment to the coaatline

santa barbara, california

offshore breakwaters

• rocks in a line parallel to the shore

• calmer conditions behind breakwater

• but cause wave patterns to change

• are expensive

groynes

• stone or wooden fences

• create wider beaches

• but terminal groyne syndrome further down

reventments

• angled walls just offshore

• breaks down forces of waves

• more cost effective than sea walls

• but require constant maintenance

• can also reduce access to the beach

cuspate foreland example

dungeness

positive feedback at spurn head

spit:

rising sea levels

faster erosion of spurn head spit

which in turn causes increased erosion of the spit due to abrasion

sand dunes:

increased storms blow damage dunes and increase blowout

increased sediment increases aeolian erosion of dunes

vegetation also damaged meaning that the dunes are held together less well

positive feedback at flamborough head

made of chalk, therefore not a resistant rock type

more storm events remove the sediment at the bottom of the cliff

leaves the cliff more exposed to erosion

this material is then used in abrasion against the cliff

negative feedback along a coastline

a shore is eroded making a wave cut platform wider

this then helps to dissipate the wave energy which prevents furtehr erosion occurring

negatuve feedbakc at spurn head

increased erosion of the spit means there is more suspended sediment

this sediment is often deposited offshore to make an offshore bar

these offshore bars can then dissipate incoming wave energy, reducing future erosion of spurn head - gives spit time to recover

negative feedbakc at flamborough head

increased storm events may lead to cliff collapse

this will lead to chalk deposits sitting at the bottom of the cliffs

this will then slow down the rate of future erosion

what type of rock is the majority of the holderness sediment cell

clay

what number sediment cell is the holderness coastline

2

impact of storm xaver (2013) on hemsby

7 homes, sand dunes, and a lifeguard tower destroyed

storm xaver

december 2013

coincided with spring tide (strongest)

storm surge reached 6m in blakeney is north norfolk

total economic loss of c. $100 million

how many people were killed as a result of storm xaver and how many were evacuated

2 killed and 18,000 evacuated

how many people died during the 1953 storm surge in the same place as storm xaver and what was the damage in todays money

307 people died - cost equivalent of £1.2 billion

what lowered the damage of storm xaver

improved flood defences in 2013

incl the thames barrier, which protected 800,000 homes

improved forecasting and emergency communication

how do storm surges form

caused by areas of low pressure over the coast

low pressure causes the water to dome causing local sea level to rise

a storm event can drop air pressure by 30mb - a decrease in pressure of 1mb can cause the local sea level to rise by 1cm

impacts accentuated at high tide (especially during spring tides) and when the sea bed shallows approaching the coast

mangrove destruction in SE asia

removed to make way for rice paddies, rubber trees, palm oil plantations etc.

no longer there to provide natural barriers to coastal flooding and sea level rise

farmers also use chemicals and pollutants which then make their way into the water supply

loss of mangroves contributes to nearly 1/5th of emissions from deforestation

also struggle to survive in warmer temperatures