Coasts case studies Flashcards
what is the Portland bill to Selsey bill sediment cell
- a coastal management area located on the south coast of the UK
- one of the 11 sediment cells identified in the UK
what is the Nile delta how has its coastline receded
- A region in northern egypt where the nile empties into the mediterranean sea
- receding at an average rate of 1.2 metres a year - one of the highest coastal erosion rates in the world
what physical factors are causing the nile delta to recede
sea level rise - causing more frequent and intense coastal flooding and erosion
natural subsidence - located on a soft and compressible sedimentary basin which is naturally sinking ; exacerbating the effects of sea level rise
Storm surges - vulnerable to storm surges because of its low lying topography and location (situated in an area where several large scale weather systems converge)
what human factors are causing the nile delta to recede
dam construction - construction of dams (aswan dam- reduced sediment supply from 130 million tonnes to 15 million tonnes a year) upstream have reduced amount of sediment that is transported downstream to the delta - not receiving enough to keep equilibrium
water diversion - diversion of water from the nile for irrigation is also reducing the amount of sediment
groundwater over extraction - causing lank to sink and exacerbating effects of sea level rise and natural subsidence
urbanisation development- rapid pop growth of delta region have led to construction of infrastructure in vulnerable areas - reduced natural protection provided by coastal ecosystems like mangroves and wetlands
over fishing and pollution - also contributing to loss of coastal ecosystems
climate change- burning of fossil fuels and deforestation causing sea level rise and more frequent intense storms
where is Bangladesh
country in south east asia
situated at delta of 3 rivers which flow into the bay of bengal in the south
what physical factors make bangladesh vulnerable to storm surges
low lying topography - only a few metres above sea levels - most areas only 1-3 metres above
geographical location - area frequently affected by severe weather events
shape of the coast - funnel shaped - concentrates force of incoming storm surges making them more destructive - bay also has shallow water allowing surges to travel further inland
river delta - countrys river delta has complex network of channels creeks and islands which are easily inundated by storm surges
what human factors make Bangladesh vulnerable to storm surges
population density - high population density especially along coast so increased risk of casualties and damage
urbanisation - resulted in construction of infrastructure in areas that are vulnerable making them more susceptible to damage
deforestation - has contributed to soil erosion and land loss reducing natural barriers to storm surges
agricultural practices - has lead to soil erosion which can increase risk of land loss during a storm surge
poor infrastructure - poorly maintained drainage systems and flood barriers
climate change -burning of fossil fuels and deforestation - leading to more frequent and intense storms and sea level rise
where is the maldives
small island nation located in indian ocean
what physical factors make the Maldives vulnerable to flooding
topography - one of lowest lying in the world- average elevation of 1.5 metres and highest point of 2.4 metres - vulnerable to sea level rise and storm surges - IPCC- sea level predicted to rise 50m by 2100 which would inundate 77% of its land area
what human factors make the maldives vulnerable to flooding
coral reef degradation - play a crucial role in protecting the maldives from wave action and storm surges - degradation caused by climate change overfishing and pollution is reducing their effectiveness
rapid population growth - led to construction of infrastructure in areas that are vulnerable - now more susceptible to damage
overdevelopment - infrastructure led to filling of wetlands and mangroves- natural barriers to flooding
lagoon dredging - removing more natural barriers
deforestation - contributes to soil erosion and land loss - removing natural barriers
climate change- human activities leading to more frequent and intense storms
poor infrastructure - poorly managed drainage systems and flood barriers
whats being done to prevent the maldives from flooding
building sea walls
promoting sustainable tourism - reducing carbon emissions from transportation
developing early warning systems - give time for preparation and evacuation
investing in renewable energy -decrease dependence on fossil fuels and decrease greenhouse gas emissions
encouraging sustainable development - preserving wetlands and mangroves
whats being done to reduce how vulnerable bangladesh is to storm surges
building and maintaining coastal embankments
developing early warning systems
establishing cyclone shelters - built in coastal areas for people during storms to prevent injury/death
promoting community based disaster risk reduction
encouraging sustainable land use - such as afforestation to reduce soil erosion and strengthen natural barriers against flooding
investing in climate resilient infrastructure - such as bridges and roads to ensure essential services not disrupted by storms
what was the 2013 north sea storm surge
- a major flooding event that affected parts of netherlands , germany and the UK
what caused the 2013 north sea storm surge
- low pressure system developed in the north atlantic and moved towards the north sea
- brought strong winds and heavy rainfall - led to significant rise in sea level
what physical factors contributed to the 2013 north sea storm surge
high tide - coincided with high tide which made an even higher sea level increase
coastal geography - north sea is shallow with a funnel shape that will concentrate power towards coastlines