Coasts EQ3 Flashcards
how do coastal erosion and sea level change alter the physical characteristics of coastlines and increase risks
name a reason why sea levels are rising?
thermal expansion/melting ice caps and glaciers
what is the case study for sea levels rising?
Kiribati
where is Kiribati located?
middle of the pacific ocean
What’s the problem in Kiribati?
sea level is rising by 1.2cm a year
low - lying islands
what is the future for Kiribati?
most of its islands could disappear in 50 years
migration with dignity policy to allow people to apply for jobs in neighbouring countries
what is Kiribati used for currently?
agriculture and fish farming projects
what are the 3 ways to change the sea level in the long run?
eustatic , isostatic , tectonic
what is eustatic sea level change?
when the sea level rises or falls as a global event
how does eustatic sea level change work?
- cold glacial periods, precipitation falls as snow
- forms huge ice sheets that store water normally held in the oceans
- sea levels fall
- at the end of the periods temperature increases and the ice sheets being to melt
- sea levels rise again
what is isostatic sea level change?
when land rises or falls relative to the sea as a local event
how does isostatic seal level change work?
- in glacial periods ice sheets make the land sink
- the ice begins to melt at the end of the period
- reduce ice causes the land to readjust and rise
what is a submergent coastline?
the results of sea level rise or isostatic sinking
name 2 features of a submergent coastline..
any from:
- a ria
- a fjord
- a fjard
- dalmation coast
what is a ria?
sheltered winding inlets with irregular shorelines
how do rais form?
when valleys in a dissected upland area are flooded, it provides a natural harbour with the deepest water at its mouth
where is there and example of a ria?
south-west England
kings-bridge estuary - Devon
what is a fjord?
long -steep sided glacial toughs
how do fjords form?
glacial toughs are flooded by a rise in sea level, they are much deeper inland which are long and steep sided with a U shaped cross - section and hanging valleys
where is there an example of a fjord?
Norway, New Zealand, Chile
what is a fjard?
a flooded inlet with a low rocky bank on either side
how to fjards form?
formed by a post - glacial drowning of glaciated lowland rocky terrain
where is there an example of a fjard?
Gulf of Finland, western Scotland
what is a dalmation coast?
river flows almost parallel to the coast rather then right-angles
where is an example of a dalmation coast?
Croatia
what is an emergent coastline?
a result of isostatic rebound
what are the two features of a emergent coastline?
- raised beaches
- fossil cliffs
what is a raised beach?
beaches raised above the present sea level
how to raised beaches form?
land rising as a result of isostatic recovery and caused shoreline platforms and beaches to rise
where is an example of a raised beach?
West coast of scotland
isle of arran
what is a fossil cliff?
remains of eroded cliff lines
how do fossil cliffs form?
marine erosion
where is an example of a fossil cliff?
west coast of scotland
where is an example of coastal erosion and defence?
the Holderness coastline
where is the holderness coast located?
stretch of coat in the North-East of the UK with the north sea to the east
how much of holderness coast has been lost already?
4km
what are the 4 reasons why coastal erosion is such an issue?
geology, fetch, longshore drift, subaerial processes
