geography paper 2, edexcel

longshore drift

The movement of water and sediment down a beach caused by waves coming into shore at an angle. the uk moves material from west to east

how are beaches formed

when material is transported by longshore drift and deposited by constructive waves.

where are sandy beaches found

sheltered bays, they have shallow gradients

where are pebble beaches formed

areas where cliffs have been eroded by high energy waves, they have a steep gradient

spit

narrow ridge of shingle stretching out into coastline, forms due to longshore drift at a change of coastline. shingle gets deposited

bar

ridge of shingle that extends across a bay/rive mouth. behind it, fresh/saltwater forms a lagoon.

settlement affecting the coastline

20million people live near the coast. 29 villages lost due to coastal erosion

tourism affecting the coastline

13% jobs at Dawlish are tourism. coasts often managed for tourists (with groynes etc)

infrastructure affecting the coastline

roads/railways/shipping ports/oil refineries.
esso sees 2000 ships dock every year

construction affecting the coastline

dredging the sea to construct ports can have adverse affects on wildlife. they can also adjust the sediment cells

agriculture affecting the coastline

farmland will be impacted due to sea level rise because of increased coastal erosion because it's low economic value and low priority in management

rising sea level uk

english channel expected to rise 15cm by 2030, caused by thermal expansion and melting ice sheets/glaciers

what is a storm/storm surge

large increase in sea level due to a storm. strong winds drive up the waves, whilst low pressure allows the sea level to rise up 3m above normal.

hold the line

maintain the existing coastline with defences

managed realignment

allow the shoreline to change naturally, but manage the process and the impacts

advance the line

build new defences on the seaward side

sea wall

-protects base of cliff. made of resistant concrete that deflects energy
-expensive and ugly, restricts access

groynes

-maintain a wide beach and attract tourists
-high maintenance cost, could impact other areas of coastline in sediment starvation

beach replenishment

-looks natural, attracts tourists, cheap
-material easily eroded and needs constant replenishment

slope stabilisation

-prevents mass movement, safer for people using the beach
-difficult to install, very expensive

waves

caused by friction that is generated when wind blows across the surface of the sea

destructive waves

strong winds, powerful waves, cause coastal erosion. tall, steep. backwash stronger than swash, so material is carried out to sea

constructive waves

light winds, cause deposition not erosion. stronger swash, so material is deposited on the beach

attrition

small rocks collide with eachother. break up, becoming smaller and rounder, until the rock becomes sand

abrasion

rocks thrown against the coastline. wears the coastline away over time

hydraulic action

large waves break against the cliff. water forced into the faults/cracks causing immense pressure. when it is released, it produces a force that makes the crack wider.

solution

chemicals in the sea react with the rock so it dissolves. occurs mainly with limestone.

discordant coastline

bands of different rock strengths run 90degrees to coastline. in dorset, clay, chalk and limestone form a discordant coastline

concordant coastline

bands of rock run parallel to the coastline

headland

rocks of higher resistance erode slower. as a result, high resistance rocks protrude out producing headlands

bays

formed in the same way as headland. constructive waves often bring sediment to form a beach.

cliffs

made through the process of hydraulic action and abrasion. destructive waves create a wave cut notch. as the notch gets eroded, the cliffs above become unstable, collapse, and are removed by waves

wave cut platform

below a wave cut notch, an area of exposed rock is left, which is not smooth. it continues to get eroded

cave

destructive waves break against the cliff face. hydraulic action widens the crack, eventually widening enough to form a cave

arch

waves erode the cave via abrasion and hydraulic action, which cause them to break through the middle of it forming an arch

stack

continued erosion on the base of the arch weakens it until the roof collapses, leaving a stack like Old Harry Dorset

mechanical weathering-freeze thaw

water enters cracks and in cold climates, freezes, expanding by around 10%. pressure weakens the cliff face.

chemical weathering

acid rain contains carbonic acid which dissolves limestone

biological weathering

roots of plants and trees, burrowing animals and nesting birds all weaken the rock

slumping

after rainfall, permeable rock becomes heavy and slips to a permeable rock in rotations

rock falls

sudden fall of rocks often due to prior weathering or growing a wave cut notch which resulted in an unstable cliff face

sliding

same as slumping but occurs on a bedding plane or a flat surface

sedimentary rocks

layers ontop of eachother, trapped water squeezed out

metamorphic rocks

rocks that change via heat/pressure
granite-gneiss
shale-slate

igneous rocks

intrusive magma cools inside volcano, big grains-granite
extrusive lava forms outside volcanoes small grains-basalt, pumice

uk rock types

tees exe line-
north/west\=more faults, more resistant, granite
south/east\=less resistant, chalk, clay, limestone

human alteration to south downs

-arable farming on lower slopes became mini ecosystems for animals
-large leaved lime woodland now cleared
-3 towns attract walkers and riders

drainage basin of a river

source
tributary
confluence
drainage basin
watershed
main river channel
mouth

tributary

river or stream flowing into a larger river

confluence

the junction of two rivers, where one meets another

drainage basin

the area of land drained by a river

watershed

area of land which separates water flowing into different rivers

lower course

-large discharge
-wide
-deep
-high velocity
-huge sediment load
-small particles

middle course

-medium discharge
-increasing width and depth, velocity and sediment load
-decreasing particle size because of attrition

upper course

-shallow
-little discharge
-low velocity
-low sediment load
-large sediment particle size

suspension

light material carried by a river

saltation

small pebbles and stones bounce along the riverbed

traction

large boulders rolled along the riverbed

delta formation

-river splits into dis-tributaries
-bars build up in the middle of the main channel
-river slows as it approaches the sea and the river becomes less efficient because the hydraulic radius drops

throughflow

stream of groundwater

surface runoff

rain that flow over land before reaching a channel

groundwater flow

part of streamflow infiltrated ground has entered an been discharged into the stream channel via seepage water

interception zone

rain never enters soil because it is intercepted by trees

transpiration

plants absorb water and give off vapour

infiltration

water on ground enters soil

natural levee formation

-form beside the river bank where it first floods
-river reaches bankful and deposits sediment where flow is slower, building a bank

artificial levee formation

built by engineers to prevent flooding

slow mass movement

soil creep dislodges tiny particles to move down

rapid mass movement

landslides and mudflows because sides are steeper, and rainfall

v shaped valley formation

As the river erodes vertically down over it leaves behind valley sides that are shaped like a letter V. This is because as it erodes straight down it leaves very steep valley sides that are then attacked by weathering processes such as freeze thaw and biological weathering. This weakens the valley sides which may collapse or move down slope due to mass movement processes such as slumping or soil creep. The river can then erode this material and move it away, leaving behind the characteristic V shape.

interlocking spur formation

-as river cuts vertically into the limestone, it produces steep sides and winds around areas of more resistant rock
-produces ridges of land which jilt into the river valley, looking interlocked

floodplain formation

-lateral erosion causes meanders to migrate across a valley floor and make it wide and flat
-floodwaters spread across the valley floor
-less energy for transport and alluvium deposited

meander formation

-heliocidal flow means thalweg moves laterally
-thalweg directed to outside of the bend, undercutting the bank and creating a river cliff
-sediment deposition caused by slow flow on outer bend

storm hydrographs

-falling limb\=period when a river's discharge is falling
-lag time\=period between peak rainfall and peak discharge

steep hydrograph

-greater erosion, rising limb, sediment road, surface runoff, rain/impermeable rock
-shorter lag time, drainage basin

flat hyrograph

-lower peak discharge, sediment load, rising limb, surface runoff
-long/narrow drainage basin
-more infiltration, afforestation, lag time

flood relief channel

diverts river. very expensive- 1km in rotherham cost 14million

dredging

increases channel depth
increases flood risk downstream

levees

allow safer riving nearby. very expensive, river medway 320m stretch for 200k

flood walls

useful, cheap, one off, useful for cramped cities

river channel restoration

meanders built to slow down water. improved ecology. 1.2m for 2km

floodplain retention

lowering floodplain, 1.2m for 2km

uk population growth from 1960 to 2017

52million to 65million

population increase in london between 2003 and 2013

13.8%

population growth in london caused by

1.rising birth rate because of more 20s mothers, women from the 70s choosing to have children in their 40s and migrant women having higher fertility rates
2.net immigration

how many long term immigrants accepted in 2014

640,000

net migration 2014 UK

320,000

2 main causes of large immigrations

1-EU membership, allowing free movement between other countries
2-globalisation-london's knowledge economy attracting highly qualified/skilled workers

what percentage of all migrants go to london

43%

number of elderly dependent increase from 1911 to 2011

5-17%

youthful population decrease from 1911 to 2011

30-18%

characteristics of the rural periphery

-low pop density
-older populations
-lower incomes (farming/tourism, seasonal and minimum wage)
-high transport cost
-migration away of younger people

transport improvements to reduce urban/rural differences

-the HS2 railway links london, birminghamd, manchester and leeds.
-A9 dual carriageway between Perth and Inverness
-scotland, north wales or cornwall dont have motorways

enterprise zones to reduce urban/rural differences

-uk government offers help with startup costs, access to superfast broadband and reduced profit tax
-24 in 2015
-driving force of local economies, create jobs
-attract more FDI, bring jobs across England

UK regional development grants reducing differences between rural and urban areas

-available over more of the UK with most in scotland, ireland and wales.
-include grants to help businesses start up.

change in industrial structure over time

1918- construction reduced because of WW1
1981-energy and water employment went down because coal mines shut own

changes to the UKs primary and secondary sectors since 1980

-jobs in primary sector halved
-coal mine employees were 250,000 in the 70s, now 4000.
-farming lost 100,000 jobs from 1980 to 2015

employment opportunities in the North

-nissan europes largest car factory in sunderland
-transport companies like arriva
-call centres like tesco
-wage 40% lower than london, need more lucrative employment types

the new economy

-london involved in more globaltrade and investment and has a huge number of quaternary and tertiary jobs

the knowledge economy

-requires degrees, specialist training etc.