contemporary environments Flashcards
1
Q
urbanisation
A
the increase in the proportion of the population living in urban areas
2
Q
urban growth
A
the increase in the total population of a town or city
3
Q
urban expansion
A
the increase in size or geographical footprint of a city
4
Q
what are cities important for
A
-the organisation of economic production
-the exchange of ideas and creative thinking
-social and cultural centres
-centres of political power and decision making
5
Q
3 causes of urban growth
A
-natural population growth
-industrilasation
-rural to urban migration
6
Q
2 categories of reasons for rural to urban migration
A
push factors
pull factors
7
Q
4 processes of urbanisation
A
-urbanisation
-suburbanisation
-counter urbanisation
-urban resurgence
8
Q
suburbanisation
A
the decentralisation of people, employment and services towards the edges of an urban area.
9
Q
counter urbanisation
A
population movement from large urban areas to smaller urban settlements and rural areas
10
Q
urban resurgence
A
population movement back to urban areas
11
Q
why does suburbanisation usually occur
A
when wealthier people decide to move away for a better quality of life
12
Q
issues with suburbanisation
A
-it can lead to inner city areas becoming deprived
-house prices in surburbs increase
-building on green belts
13
Q
push factors of counter urbanisation
A
-pollution
-large industrial areas
-economic decline
-overcrowding
14
Q
pull factors of counter urbanisation
A
-clean air
-more space
-better value housing
15
Q
advantages of counter urbanisation
A
-forces inner city urban areas to regenerate or face collapse
-helps reduce overcrowding and housing shortages
16
Q
disadvantages of counter urbanisation
A
-higher rural house prices
-more traffic and congestion
-conflict between elderly population and new residents
17
Q
pull factors of urbanisation
A
-opportunities
-jobs
-better healthcare
-education
18
Q
disadvantages of urbanisation
A
-increase in unplanned housing
-poor likely to be exploited
-large social divides
- water pollution increased
19
Q
when does urban resurgence usually occur
A
when schemes put in place to improve the quality of life are put in place to economically grow and regenerate the urban area
20
Q
megacities
A
urban areas with a very high population with over 10 million people
21
Q
world cities
A
cities that have significant political and economic influence on a global scale
22
Q
social affects of urbansiation
A
-multiculturalism and increasing diversity
-improves access to different jobs,healthcare, eductaion due to larger investments within cities
-access to wide range of jobs increases quality of life
23
Q
economic effects of urbanisation
A
-shift in employment from primary sector to tertiary sector
-areas where people have migrated away from the economy may decline because less people are contributing to the economy
-economic inequalities
24
Q
deindustrilisation
A
the long term decline of a countrys manufacturing and heavy industrys
25
key drivers to industrialisation
-reduced need for labour
-reduced demand
-globalisation of manufacturing
-increased costs
26
decentralisation
the process of urban developments away from he city centre
27
rise of the service economy
an economy where the dominant source of economic growth is through providing services rather than goods
28
drivers of the tertiary sector expansion
rising affluence
technological change
29
primary sector
natural resource exploitation eg. mining, farming, oil extraction
30
secondary sector
manufacturing goods
eg. making clothes, vehicles, appliances
31
tertiary sector
providing services
eg. call centres, banking
32
quaternary sector
providing information
eg. teaching, stockbrokers
33
urban regeneration polices
1980s - 1998 urban development corporations (UDCs)
1981- present enterprise zones
1982 - present government grants
1992 - 2008 english partnerships
1990s - present new initiaives
34
urban development corporations
1980s-1998
-UDCs created policies to ensure effective use of land, develop industry, provide social housing facilities and overall enhance the quality of deteriorated areas
35
enterprise zones
1981- present
enterprise zones are specific areas of land with economic incentives such as tax breaks and government support that aim to entice business to incest into an area that would benefit from business
36
government grants
1982 - present
the government created a number of grants that entice private investors to develop and regenerate urban areas.
the urban development grant and urban regeneration grant merged into the city grant (1988) allowing development plans to bypass local authorities making developments easier to go ahead
37
english partnerships
1992 - 2008
-english partnerships was a national regeneration agency that aimed to develop derelict and underutilised areas. they had certain powers to enable regeneration and development such as issue a compulsory purchase order which meant land could be bought without consent of the owner therefore removing barriers to development
38
new initiatives
1990s - present
-several new bottom up schemes have been employed in the uk where the local community is encouraged to be a part of the regeneration process and therefore benefit from it eg city challenge, the single regeneration budget and european funding programmes
39
a citys urban form refers to
the physical characteristics of a city
40
physical factors which can influence urban form
-natural resources
-water
-topography
-climate and land types
41
human factors which can influence change of urban form
-wealth and development
-planning
-patterns of growth
-economic activities
-past developments
42
factors that urban form changes over time in response to
-population
-environment
-economy
-technology
-polices
43
contemporary characteristics of megacities
-urban sprawl
-edge cities
-high density living and intensification of urban centres
-residential differentiation
-redevelopment and conservation
-infrastructure
-transit orientated development
-car dominated urban form
-environmental problems
44
infrastructure
the physical and related organisational structure needed for society to operate
45
new urban ladnscapes
-mixed use developments
-fortress developments
-cultural heritage quarters
-edge cities
-gentrified areas
46
mixed use developments
-mixed use developments blend residential, commercial, cultural, institutional and industrial uses which are interconnected physically and also functionally
47
fortress developments
fortress developments are where areas are secured off from public acess and only certain people with permission are allowed to enter
48
cultural heritage quarters
cultural heritage quarters are large areas within an urban an urban area that are recognised as having particular cultural importance
49
edge cities
an area of business, shops and entertainment services on the outskirts of a city usually by major transport links
50
gentrified areas
gentrification is a form of inner city regeneration often involving the movement of affluent usually young middle class people into traditionally run down areas
51
the concept of the post modern city
the idea that contemporary cities are changing their industries, architectual style and land use in order to keep up with socioeconomic changes in society
52
usual characteristics of post modern western city
-characterised by unusual architecture
-tertiary and quaternary industries are the main sectors of the economy
-fragmented urban forms rather than things being concentrated in one area
-a large amount of socioeconomic inequality exists
53
gentrification
the process of housing improvement slowly associated with low income groups being displaced and more affluent people moving in.
54
reasons for gentrification
-the rent gap
-a changing household composition and demographic
-proximity to inner city and employment opportunities
-reputation of cultural and art
-may be encouraged by local council
55
benefits of gentrifictaion
-rise in general price level of propensity and increasing number and range of services
-increased tax revenue for local authority
56
costs of gentrification
-low income groups get priced out
-tension between new and old residents
-threat to the community
57
CBD
-this is where commercial, financial and business activities are concentrated
-age of buildings usually decreases in increasing distance from the city centre
58
inner city
-in LICs high cost residential areas are usually located here
-in HICs the high land price means developments are densley compacted
-the inner city is also where industrial sites are usually located
59
suburban areas
in HICs they are often higher in value
-effective planning means these areas often have large open spaces and houses are usually larger and more expensive
-in LICs areas on the edge of cities tend to have very poor quality housing that have been constructed with little or no regulations
60
social segregation
where groups of people live apart from one another or from the larger population due to factors such as wealth, ethnicity, religion or age
61
strategies to manage urban areas
-city minimum wages
-fair rent and housing policies
-recognising informal housing issues
-encouraging multicultralism
62
categories of urban polices
-retraining
-economic policies
-environmental policies
63
reurbanisation
the large scale government backed movement of people into the city centre as part of regeneration
64
trends in reurbanisation
-increase in the construction of centrally located residential areas
-increase in studentification
-rapid population increase
growth of 24 hour culture and central entertainment districts
-growing effectiveness of public transport networks
65
microclimates
when urban areas create their own climate and weather
66
causes for microclimates
-changes to land surface eg concrete
-fewer trees that prevent sun for being absorbed from its shade
-dark rooftops and dark pavement
-tall buildings reflecting and absorbing sunlight
-car engines and factory exhausts producing heat
-fewer plants for evapotranspiration
-poor buildings insulation release heat at night
67
two levels in microclimate domes
urban canopy- processes acting in the spaces between buildings and roof top level
-urban boundary- processes acting above roof level and extends downwind as a plume in the surrounding rural areas
68
urban climate characteristics
-high pollution levels
-fog and photochemical smog
-more precipitation
-lower relative humidity
-more cloudy
-increased thunderstorms
-lower wind speeds with the exception of tunneling effect
-pressure gradients
-greater diurnal tempreture range
69
the urban heat island effect
a phenomenon where the characteristics of urban areas and the activity within them cause the areas to produce and retain more heat than surrounding areas
70
tempreture sinks
found above green spaces and water
71
tempreture plateaus
occur in areas within the same land use
72
tempretre cliffs
occur when tempretures changes rapidly from one land use to another
73
main causes of the heat island effect
-absorption of heat by urban surfaces
-heat from human activities
-less evapotranspiration
-air pollution
74
why is there more precipitation in urban areas
-urban air pollutioin results in more condensation nuclei which helps the fomration of clouds
-air is warmer leading to more precipitation
-air turbulenece amogst buildings of varying heights and heat island related convection promote the uplift of air to rise and cool below dewpoint and allowing water vapour to condense in order for precipitation to form
-dust and pollution from industry increase condensation nuclei that seed the cloud droplets
75
fog
ground level cloud
when visibility is less than 1000m
76
why do urban areas have higher levels of fog
urban areas generate large amounts od dust and pollution and these particulates act as condensation nuclei and trigger cloud formation
77
advection fog
formed when warm moist air moves horizontally over a cold surface
78
radiation (ground) fog
formed by the radiative cooling at the surface. it takes places from the top of the fog layer, mixing continues within the fog layer creating further cooling at the surface
79
conditions necessary for radiation fog
-long, clear, cloud free colf night
-shallow layer of moisture near the ground
-light winds
80
steam fog
forms when cold air moves over warm water or surface .water evapourates increasing the dew point and if mixing is sufficient becomes saturated. the colder air directly above is heated from below and rises appearing like steam
81
thunder is a result of
the sudden increase in pressure and tempreture from the lightning causing a rapid expansion of the air around it
82
why are there more thunderstorms in urban areas
due to strong urban convection as a result of heat energy building up in the atmosphere
83
how lighting forms in urban areas
strong urban convection creates an updraft of humid hot air which rises and cools and condenses rapidly. continued updrafts of warm humid air carried upwards results in the formation of cumulonimbus clouds.
air is moved by updrafts and downdrafts so water droplets increase in size. when large enough to overcome gravity the fused ice crystals will fall. as the raindroplets split in the updrafts there is an electrical discharge into the air
84
why are rural wind speeds higher
the ground is smoother
85
two key effects influencing wind in urban areas
urban canyons
venturi effect
86
urban canyons
(canyon effect)
powerful gusts of winds channeled down relatively narrow streets bordered by high rise buildings funneling and concentrating winds
87
venturi effect
a particulary violent form of gusting caused in particularly narrow gaps of air by rushing to replace low pressure vortices beyond structures
88
turbulence occurs
around buildings
wind is deflected downwards as it hits the face of a building.wind can be deflected around the sides of the buidldings or it can flow over the top. this flow of air around buildings can create vortices
89
sources of particulates
-vehicle exhausts
-industrial activites
-construction work
90
damaging impacts of urban air quality
heart problems
headaches
tiredness
green house effect
haze
respirartory problems
acid rain
91
smog
mixture of smoke and fog
92
when does smog occur
when smoke particulates and sulphur dioxide from burning coal mix with fog
93
what is photochemical smog caused by
when particulates react with UV light from the sun
94
why does photochemical smog stay at ground level
due to a tempreture inversion. cooler air is trapped below warmer air
95
polices to reduce air pollution
-legislation
-technological improvements
-reducing congestion
-vehicle restrictions
96
-urban areas have higher rates of precipitation compared to rural areas because
-pollution- holds more condensation nuclei
-warmer air- the air holds more moisture
97
characteristics of urban drainage
-more surface run off
-less vegetation so less evapotranspiration
-urban rivers are primarily the exit for water transferred through the drainage basin but also important stores
-resivours, lakes, ponds and swimming pools are permanent stores but vulnerable to evapouration
-depression storage such as puddles
-interception storage is reduced due to replacement of vegetation by impermeable surfaces but have drains
-drainage structures have been built
98
flood hydrograph
shows how river discharge responds to storm events
99
why does discharge rise quickly on a flood hydrograph
due to rapid surface runoff
100
why does discharge fall at a slow rate on a flood hydrograph
due to base flow increasing
101
base flow
the normal flow of river derived from the through flow and ground water flow
102
hard engineering flood management
-river straightening
-natural leeves
-embankments
-diversion spillways
-river channelisation
-dredging
-dams and resivours
103
soft engineering flood magement
-afforestation
-river bank conservation
-flood plain zoning
-river restoration
104
sustainable urban drainage
systems that are designed to manage the flow of urban water sustainably. SUDs use techniques that recreate natural drainage systems so water is allowed to flow gradually through the system before being removed as quickly as possible
105
SUDs techniques
-swales
-permeable road and pavement surfaces
-infiltration trenches
-bioretention basins
-detetion basins
-rain gardens
-green roofs
106
swales
wide shallow drainage channels that are normally dry
107
infiltration trenches
grave filled drains and filter strips
108
bioretention basins
gravel or sand filtration layers beneath reed beds and other wetland habitats to collect store and filter dirty water
109
detention basins
excavated basins to act as holding ponds for water storage during flood events
110
benefits of SUDs
-slows down surface runoff and risk of flooding
-reduces risk of sewer flooding
-prevent water pollution
-recharge ground water to help drought
-provide valuable habitats for wildlife
-create green spaces
111
river restoration involves
removing all hard engineering adaptations to restore meanders, wetlands and floodplains. drainage and flood management is returned to nature
