Contemporary Urban Environments Flashcards
What is urbanisation?
Urbanisation is the growth in the proportion of a country’s population that live in an urban environment compared to rural environment.
In 2008 how many people lived in urban areas?
3.3 billion
Where are urbanisation rates worse?
Poorer regions of the world (LICs)
What is urban growth?
Increase in the proportion of people living in urban areas.
How much of the world’s wealth comes from cities?
75%
How much has Mumbai’s population grown in 20 years?
40%
In 2050, how many people are predicted to live in cities in India?
700 million
Where is Asia’s largest slum?
Mumbai
What is an economic process associated with urbanisation?
- Large companies moving to cities.
What are three social processes associated with urbanisation?
- Increased poverty and crime
- Segregation
- More services such as schools
What are two demographic processes associated with urbanisation?
- Most people are young and are part of the working population.
- Ethnically diverse.
What is urban sprawl?
The unplanned growth of urban areas into the surrounding countryside.
What are the three most urbanised regions in the world?
North America (82%), Latin America and the Caribbean (81%) and Europe (74%).
How much is the total world urban population predicted to be by 2045.
Six billion
In recent years why have some cities have experienced population decline?
Economic contraction (Detroit, USA)
Low fertility rates (Nagasaki, Japan and Busan, South Korea)
Emigration (Poznan, Poland)
Natural disaster (New Orleans, USA- Hurricane Katrina)
What are squatter settlements?
Squatter settlements are densely packed ‘houses’ near city centres made with scrap materials. They have inadequate services and are ‘non-legal’.
What is a megacity?
A city with a population over 10 million.
How many megacities were there in 1990?
10
How many megacities were there in 2020?
30
How many megacitites does the UN predict to exist by 2030?
43
In 2015 what was the largest city and what was its population?
Tokyo (37.4 million)
Is Tokyo’s population expected to increase or decline?
Decline by almost 900,000 by 2030.
What are metacities?
A conurbation of more than 20 million people.
What does the Chinese government plan to do in terms of metacities?
Merge nine cities in the Pearl River Delta to create an urban areas 26 times larger than Greater London.
How much on Kenya’s GDP comes from Nairobi?
Almost 20%.
What is ‘Nappy Valley’
An area stretching from Clapham westwards towards Fulham which has a high proportion of young families.
Push factors of rural-urban migration.
- Over-farming, soil erosion and low yields due to rapid population growth.
- Inadequate medical provision.
- Natural disasters.
- Wars and civil wars.
Pull factors of rural-urban migration.
- Employmeny in factories in service industries which usually pay better.
- Better quality social provisions such as healthcare and education.
- Percieved better quality of life.
Name 5 problems with urban sprawl.
- Habitat loss.
- Requires more infrastructure which is not very economically sufficient.
- Causes more commuting from the suburbs to city and so more traffic congestion and fuel consumption.
- Decline of retail in city centres due to decentralisation.
- Increased flooding due to more surface runoff.
In 2017 how many people were estimated to live in slums?
900 million
Approximately how many people live in slums in India?
104 million
What are informal settlements called in Brazil?
Favelas
What are informal settlements called in West Africa?
Bidonvilles.
Between 2000 and 2015 how many people living in slums did the UN report as having gained access to improved water sources and sanitation facilities?
320 million
What initiatives have been mainly used to help improve slums?
Slum upgrading programs and self help schemes.
What is Slum Dwellers International (SDI)?
An organisation which gives a voice to people living in informal settlements and links up poor communities across Africa, Asia and Latin America.
What is the largest slum in Asia?
Dharavi, Mumbai
What types of small-scale industries are located in Dharavi?
Small manufacturing units produce leather goods, aluminium bricks and pottery.
They also recycle plastics for both the domestic and international markets.
What is the state government’s plan to redevelop Dharavi?
£1.1 billion plan to transform it into a modern township complete with proper housing, shopping complexes, hospitals and schools.
In London how much have average house prices risen by between 2010 and 2019?
70%
What is gentrification?
The buying and renovating of properties, often in more run-down areas, by wealthier individuals.
What is Portland Road an example of?
Gentrification
What was the first social housing on Portland Road?
Nottingwood House
What is the average price of houses of Portland Road?
Just over £3 million
What is counter-urbanisation and what act encouraged it?
The movement of people from large urban areas into smaller urban areas or rural areas.
New Towns Act 1946 encouraged this with the construction of Milton Keynes and Basildon.
What is decentralisation?
The movement of population and industry from the urban centre to outlying areas.
What is deindustrialisation?
The loss of jobs in the manufacturing sector, which mainly occured in the UK in the second half of the 20th century.
What is an edge city?
A self-contained settlement which has emerged beyond the original city boundary and developed in a city in its own right.
What is suburbanisation?
The movement of people from the inner city to living on the outer edges.
What is urban resurgence?
The regeration, both economic and structural, of an urban area which has suffered a period of decline.
In the 1930’s where was the main growth of suburbs?
Along main roads and suburban railway lines.
This was known as ‘ribbon development’.
What was the Green Belts Act 1947?
Green belts were created in response to out of control development.
When was ‘Right to Buy’ introduced?
1980s by Margaret Thatcher
Name a government policy which has encouraged counter-urbanisation.
New Towns Act 1946 saw 21 established by 1970.
8 were London ‘overspill’ towns.
Stevenage was the first.
Pull factors of urban areas.
- Sense of community
- High speed internet
- Car ownership
- Village schools
- Low crime rates
- Greater affluence so people have second homes
Name 3 pieces of evidence for counter-urbanisation.
- Increased value of houses in the area
- Increased use of a commuter railway station
- Conversions of former farm buildings to exclusive residences
Urban resurgence in Middlesborough.
- 57.5 hectares of land regenerated
- 5500 new homes built
- 2500 enterprises
- 450000 people live within 20 minutes
What is the doughnut effect?
Rich inner city development surrounded by ‘acres of gloom’
Urban resurgence in the Jewellery Quarter, Birmingham
- Originally a centre for jewellery making (secondary)
- Blitz bombing led to decline in areas fortune
- 30 restaurants, bars and cafes have been built (tertiary)
- 144 apartments above Harvey Nichols cost up to £350,000
- Over 3000 new homes have been built in the centre of Birmingham
Name an example of urban resurgence in the USA
The High Line, New York
How many rain gardens are there in New York?
Around 5000-6000 across the five boroughs.
What do rain gardens do?
Collect stormwater.
The soil absorbs water through infiltration.
Dropped curb which allows water to flow in and out.
Drain water in 48 hours or less.
Plants are installed and possibly a tree to intercept but also to provide shade.
How much has been spent in NYC to improve waterways?
$10 billion
How much of NYC is impervious?
72%
Who in New York plans the construction of urban drainage systems?
The Office of Green Infrastructure
Where does most of the water in New York come from?
Reservoirs about 100 miles away.
How much was spent on watershed protection in NYC?
$1.2 billion
Does NYC have a combines sewage overflow?
Yes
What are the seven steps of sewage treatment in the UK?
- Taking the wastewater away
- Screening the wastewater
- Carrying out primary treatment- solid removal
- Carrying out secondary treatment- bacteria removal
- Carrying out final treatment- final bacteria removal
- Generating power with some waste- could be hydroelectric
- Returning water to rivers and returning solids to land.
What does SUDS stand for?
Sustainable urban drainage system
What is the aim of SUDS?
Align modern drainage systems with natural water processes.
What are 4 examples of SUDS?
Wetland systems, bioswales, retention tanks and permeable pavements.
What is discharge?
The volume of water that flows in a river per second.
What is river discharge measured in?
Cumecs- m3/s
What is the discharge of the River Amazon?
209000 m3/s
What is the discharge of the River Tees?
200 m3/s
What does high peak discharge lead to?
Short lag time
What does low peak discharge lead to?
Long lag time
Name five factors which influence discharge?
- Intensity of rainfall
- Antecedent conditions
- Interception
- Infiltration
- Urbanisation
Name a location where river restoration has taken place?
Cheonggyecheon, Seoul, South Korea
When was the Cheonggyecheon river covered?
2003
It lasted 2 years
How much does the Cheonggyecheon river restoration scheme cost?
$281 million
What were the three reasons/aims for/of the Cheonggyecheon restoration scheme?
Create recreational/ecological opportunities
100,000 small businesses next to the overpass and area were polluted
Improve connectivity between north and south of the city.
How many bridges were built in Cheonggyecheon?
22
What work was carried out as part of the Cheonggyecheon restoration scheme?
Freeway and concrete deck covering the stream were dismantled
Car use was discouraged
Water from Hanang River was pumped to the area for consistent flow
A corridor runs from Seoul to ecological conservation area and it is split into three sections.
How many visitors visited Cheonggyecheon by the end of 2008?
18.1 million
Who included the Cheonggyecheon restoration in their bid to become may of Seoul and what year was it?
President Lee Myung-bak
How much did the average temperature in Cheonggyecheon decrease by once the restoration had finished?
2.5 degrees c
What was there a protest for in 2005 about in Cheonggyecheon?
Accessability
Name five sources of waste.
Industrial (chemical) waste
Food waste
Green waste
Plastic waste
Fabric waste
Why is there more waste in urban areas?
Higher population density
What two types of waste are significantly higher in urban areas?
Industrial and plastic (food covered in plastic)
Do HIC’s have better waste control/organisation?
Yes
Do LIC’s have better waste management?
Yes
E.g. using waste to build informal housing
How many oysters did New York have per person per year?
600 but water pollution decreased this.
What did a law in Ney York surrounding water pollution prevent?
Made it illegal for raw sewage to enter the Hudson but it naturally happens everytime it rains.
Has the waste been getting clearer in the Hudson since 1972?
Yes
How many people live in NYC?
8.5 million
What percentage of NYC’s sewers is where stormwater and general pollution mix and what are they called?
60% and these are combined sewers.
How much discharge of combined sewage is there per year in NYC?
1.5 billion gallons
What is a bioswale?
An area of plants, vegetation and soil which absorb water to stop it flowing into drains.
Name an example of where bioswales can be found in NYC.
Soundview Park
What percentage of impervious surfaces are rooftops in NYC?
40%, these are typically privately owned.
What sort of health issues have people in NYC experienced due to water pollution?
Eye infections
What are household recycling rates in the UK?
Around 44%
Where are unrecyclable materials sent in the UK?
EfW to be turned into energy
How many houses does 35 megawatts of EfW provide energy to?
35000
How many tonnes of waste is produced in the UK per year?
30 million
When was the highest rainfall recorded in Mumbai?
July 26, 2005
When was the day with second highest rainfall recorded in Mumbai?
July 2, 2021
Where experienced a drought just before the high rainfall in Mumbai in 2021?
Maharashtra
Dought of 50% of geographical area
How many mm of rainfall per hour do the Mumbai’s drains have?
2mm in low tide
Mumbai has lost how much of its mangrove forest between the 1990s and 2005?
40%
How many people died due to rain related incidents on July 1st 2019?
30
When was the BRIMSTOWAD project proposed?
1993 after the 1985 floods
Intended to be a long term road map for the city’s vulnarability to flooding
When did the BRIMSTOWAD project start and why?
The 2005 floods due to the financial cost of the project.
Name four reasons why urban areas are at risk of flooding.
Large areas of impermeable surfaces
Surface runoff
Discharge of water from industrial and domestic uses
Lack of tree coverage
How do SUDS work?
Extend lag time
Encourage interception, evaporation, transpiration and infiltration
Mimic natural processes to slow the movement of water of water through a landscape.
What is a SUDS?
A new approach to managing rainfall by using natural processes in the landscape to reduce flooding, control flooding and proved amenities for the community.
What are the three types of SUDS?
Source control
Site control
Regional control
What are source control SUDS?
Store the water where it falls.
- Permeable pavements
- Rain gardens
- Water butts and tanks
What are site control SUDS?
Store the water in one location but away from where it fell.
- Permanent ponds
- Directing water from roofs and carparks to bioswales
What are regional control SUDS?
Store water over a larger scale project
- Large ponds
- Permanent wetlands
What are the benefits of SUDS?
- Increase green spaces in cities
- Imrpove urban biodiversity
- Evapotranspiration reduces urban heat island effect
- Improve water quality through encouraging sediment settling, biological breakdown and filtering pollutants.
- Increase lag time which reduces peak discharge
What are the challenges of SUDS?
- Infiltration wouldn’t work in previously industrial areas as there may be pollutants.
- Cities are short on space so large systems cannot be used (use green roofs and rain gardens in this situation however).
What are the two types of flooding?
Pluvial- when intensity of rainfall increases
Fluvial- when the river rises up
How much of Austria’s waste is recycled?
63%
How much waste is produced in each household per year in the UK?
Half a tonne
In HICs, how much waste is produced per person per day?
2100g
In LICs, how much waste is produced per person per day?
600g
What country is the world’s largest waste generator?
China
What are the seven parts of the waste hierachy from most to least preferred option?
Reduce
Reuse
Recycle
Recover
Landfill
Incineration
Controlled dump
What event triggered high amount of air pollution in the UK?
Industrial revolution
How much more dust particles are there in cities than rural areas?
7x more
How much more sulfur dioxide are there in cities than rural areas?
200x
How much more nitrogen oxide are there in cities than rural areas?
10x
How much more hydrocarbons are there in cities than rural areas?
10x
How much more CO2 is there in cities than rural areas?
2x
Do cities experience increased cloud coverage and precipitation?
Yes
What causes increased temperatures in cities?
Photochemical smog
Effects of acid rain in UK.
So2 + NO -> acid rain
Sheldonian Oxford Sandstone heads have been eroded
London smog of 1952.
lasted 4 days
12000 related deaths
Anti-cyclone high pressure weather system