Urbanisation

How do urban forms and processes affect the local climate?

How do urban forms and processes affect the local climate?

Urban heat island effect= urban areas being warmer than the surrounding rural areas.

Urban heat island effect caused by following processes:

1. Combustion (transport, heating facilities, etc) releases heat

2. Combustion releases air pollution = cloud cover/ pollution dome (reflects outgoing heat back into city)

3. Deforestation = less evapotranspiration (runs down drains)

4. Construction = heat absorbed by surfaces during the day and released slowly at night (3-4 degrees hotter at night than 0.6 degrees during day)

London is 5°C warmer than surrounding rural areas

Mumbair is 5-7°C warmer than surrounding rural areas

UHI managed by: cool roof technology (white), green roads, green roofs, modern designs, urban greening

Urban microclimates

• more frequent and intense rainfall (despite less evaporation due to drains) = warm air holds moisture, rises, condenses)

• Fog and cloud = condensation nuclei from factories

• Less snow and ice (too warm)

• Winds affected: slower wind speed due to friction, turbulence (buildings cause vortices = spinning bodies of swirling air), canyon effect (gusts when channelled down streets)

• More frequent thunderstorms (warmer + rapid expansion of air)

• Poor air quality (hydroscopic pollution particles = water condenses around them = smog reduces sunshine)

New urban landscapes

• Town mixed centre developments: E.g plan to build Asda Mixed-Use Redevelopment of Park Royal in North West London (1500 homes (500 affordable), sustainable, public transport, big ASDA)

• Cultural and heritage quarters: regenerating industrial areas to have theaters, museums, galleries, improves perception of area. E.g. Jewellery quater in Birmingham.

• Fortress developments: high security for families, ££, e.g. US embassy, London

• Edge cities: increased car ownership led to cities near transport links. E.g. Croydon

Only in cities in developed countries - not MUMBAI!

Describe London’s waste

London produces 7 million tonnes of waste per year.

Sources:

• Industrial (manufacturing)

• Commercial (paper, card, food)

• Personal (private homes)

Management: incineration vs landfill

• Currently recycles 52% waste, but aim is to recycle 65% waste by 2030.

• Landfill space is running out by 2026, so plan is: no recyclable or biodegradable waste to go to landfill by 2026.

• Aim to incinerate 35% waste at Beddington. (Generates electricity for 55,000 homes)

What is a waste stream?

The flow of waste from its origin to its eventual disposal.

How do waste streams relate to economic characteristics, attitudes and lifestyles?

Waste streams vary due to these factors:

• Economic characteristics (HICs produce 2.1kg pp/day, LICs produce 0.6kg pp/day)

• Attitudes (improved health knowledge = single use, but improved environmental knowledge too)

• Lifestyles (urban dwellers produce more, processed foods produce more)

River restoration project: why did they do it?

Cheonggyecheon River Restoration project:

• Aims: to create ecological and recreational opportunities in city centre (moving from development focussed to QofL focussed)

• Attitudes of parties: transport experts worried, local businesses saw it as a threat so Seoul Metropolitan Authority provided support (parking, perks, etc)

• Activities: elevated freeway dismantled, cars discouraged, river spit into 3 zones (central historic, middle and final)

• Evaluation: popular for rest, 18.1 million tourists (2003-2008)

  Proved to be sustainable:

  1. Economically sustainable (investment double than in rest of city),

  2. Environmentally sustainable (2.5 degrees cooler, air quality improved.

  3. Socially sustainable (inclusive)

Describe London’s urban issues

Economic inequality:

• Kensington income = £130,000 but Newham’s income = £35,000

• Inner city areas are becoming more gentrified = forces poor out

Cultural diversity can lead to social segregation:

• 50% londoners not white British - unevenly distributed (60% ‘other’ in Brent, but 16% ‘other’ in Havering)

• Social segregation:

  • Hate crime (800 anti-muslim hate crimes committed July 2014-July 2015)

Strategies to reduce inequality:

1. London Living Wage (unfair cost of housing and living and childcare) (£9.75)

2. Skills training

3. Affordable housing (Sadiq Khan)

4. Police working against hate crime

Describe Mumbai’s urban issues

Economic inequality:

• high population density means ££ housing (people who cannot afford it live in slums = £2 per month, sorting waste = poor living conditions)

Cultural diversity:

Social segregation:

• Society split into horizontal divisions (religion, region, language) and vertical (caste, income, occupation)

• Indian Muslims split into muslim communities (10% less likely to have piped water, and 50% less likely to have education)

Strategies to reduce inequality:

1. Mumbai Monorail (10p per ride)

2. SPARC community toilet lock (25p per month - lighting reduces crime, hygiene reduces disease)

3. Hamara foundation (work for kids)

4. Plans to develop Dhavari into 1.1 million new homes (resident opposing the loss of community spirit)

Outline Mumbai’s waste

Only 70% waste collected: 20 % of this is processed, 50% goes to landfill = air, soil, water pollution

Strategies to reduce this:

1. Green communities Foundations (divert waste going into landfill - works with businesses)

2. Earth 5R (clean river Mithi that runs through Khurla slum - trains and educated slum dwellers)

4 processes that affect the populations of cities?

1. Urbanisation

2. Suburbanisation

3. Counter-urbanisation

4. Urban resurgence

What is urbanisation?

Growth in proportion of people living in urban areas

What is suburbanisation?

Migration of people from city centre to outskirts less crowded), due to improved transport links allowing them to commute.

Eventually leads to rich on outskirts and poor in inner city = economic and ethnic segregation

What is counter-urbanisation?

Movement of people out of the city into surrounding villages. Possible due to improved transport and communication links.

Results in new housing estates being built in villages = ££££ = young people move out = av age of area increases