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Theme 3.1, Theme 3.2, Definition: Urban as an entity refers to the…

- - - - Explain the differences in how ‘urban’ has been defined by varying locations.
        
        Urban as an entity can be defined by looking at the population size and economic base
        
        Urban as an quality can be defined by looking at cognitive maps and urban as a way of life
  - - - Definition: Urban as a quality refers to the subjective or cognitive structures of the city.
        
        Two main approaches can be utilised to identify the subjective or cognitive structure of the city.
        
        Mental Maps/Cognitive Maps
        
        Some people define the urban through mental maps. At an individual level, a person’s understanding, experience and imagination of the city is likely going to be different from another. Geographers, planners and environmental psychologists have employed mental maps to explore the qualitative and subjective dimension of urban places. Mental maps allow geographers, planners and environmental psychologists to better understand urban meaning from the subjective perspectives of the individual.
        
        'Urban' as a way of life
        
        Some other people in another location, may define urban as a way of life - having distinct culture and lifestyle, instead. Louis Wirth argues that the urban is a distinct spatial realm with its own environmental influences on individuals. It must also be understood that different ‘urban’ regions may have cultures and lifestyles that could be understood as unique and distinct. For example, in Thailand, what distinguishes Bangkok from other urban regions in the country is its frenetic and fast paced urban life. Bangkok contrasts starkly against Chiang Mai which is understood by local Thais for its more relaxed vibe.
- - - - Natural causes
        
        Solar forcing
        
        Volcanic activities
        
        Reduction in thermohaline circulation
        
        Orbital forcing
        
        Albedo and sea level change
      - Anthropogenic factors
        
        Industrialisation
        
        Deforestation
        
        Agriculture
        
        Urbanisation
    - - The greenhouse effect
      - Greenhouse gases
        
        Carbon dioxide
        
        Methane
        
        Nitrous oxide
        
        Chlorofluorocarbons
        
        Ozone
        
        Water vapour
    - - Trend of global warming
      - Predicted future temperature changes
    - - Positive feedback mechanisms
        
        Water vapour feedback
        
        Albedo
      - Negative feedback mechanisms
        
        Cloud cover
        
        Ocean sink
    - - Solar variability
      - Volcanic activity
      - Plate techtonics
      - Astronomical theory
        
        Eccentricity
        
        Obliquity
        
        Precession
      - Human activities
    - - Various pieces of evidence - as proxy data - can give us a clue into the change in climate since the last ice age.
        
        Oceanic deposits
        
        Oceanic deposits can provide evidence of climate change since the last ice age by analysing the oxygen isotope concentration. Chemical composition of the shell of a type of zooplankton contains the record of the O2 isotope type in the ocean. When they die, the shell accumulates as ocean sediment which can be recovered to show the ocean oxygen isotope concentration. During the last ice age, water is continuously removed from the ocean and stored on land as snow and ice. Water molecules are then removed by evaporation but not returned as rain. The ocean slowly become depleted of the lighter O16 isotope and have a higher concentration of the heavier O18 isotope. However, after the last ice age ended, there should be greater O16 isotope concentration.
        
        Pollen grains
        
        At a more local scale, pollen grain also shows evidence of climate change since the last ice age. Since the distribution of vegetation is largely controlled by climate, changes in plant communities, exhibited by pollen grains left behind, can be used to infer how climate has changed at a local scale. Pollen grains are preserved in lakes and river sediments, showing the changes in distribution. For example in Illinois, USA, it is found that there is a high concentration of spruce pollen grains closer to the last ice age which is indicative of a cooler climate. Today, spruce pollen does not exist in the area today, where now it is dominated by oak. This indicates that climate has changed since the last ice age as vegetation distribution adapts to climate changes.
        
        Ice cores
        
        Ice cores provide evidence of climate change since the last ice age through the analysis of its oxygen isotope ratio and the content of its trapped air bubbles. Records of past changes in climate are found from ice cores mainly from Greenland and the Antarctic ice sheets which are past snowfall compressed. This can show the O18 and O16 isotope ratio. Ice that forms during the glacial period like the last ice age would have a higher concentration of the lighter O16 isotope due to higher evaporation rates of O16 isotopes and thus less concentration of the heavier O18 isotopes as compared to the interglacial period like now.
        
        Ice cores also provide past chemistry of the atmosphere, as new snow falls onto glaciers, bubbles of ambient air are trapped in ice. The concentration of greenhouse and other gases in these bubbles yield long term geological records of the atmosphere. There is a strong correlation between past temperature and concentration of CO2 and methane, where the higher the concentration, the higher the temperature. Lower levels of these gas are found during the last ice age and have been increasing since it ended.
    - - 20m
      - 12m
        
        Explain the evidences of climate change since the last ice age.
        
        Ice cores
        
        Ocean deposits
        
        Pollen grain
  - - - Sea level rise
        
        Causes
      - Changes in agricultural productivity
      - Changes in weather patterns
      - Soil erosion
      - Human health
    - - Mitigation stratergy
        
        Strategies that slows down global warming by tackling the underlying problem of the build-up of greenhouse gases
        
        National
        
        Global
        
        Global cooperation
        
        Kyoto Protocol (1997)
        
        COP 21 (Paris 2016) and COP 24 (Katowice 2018)
        
        Scale: Individual and business
        
        Reduction of energy consumption
        
        Reduce per-capita consumption through conservation and greater efficiency
        
        Example
        
        1 more item...
        
        Impact on sustainable development
        
        Trade-offs involved
      - Adaptation strategy
        
        Strategies that deal with the effects of climate change
        
        Adapting to sea level rise
        
        Raising height of development projects in response to rising sea levels
        
        Example: In Singapore, sea levels are expected to rise by 0.76m. Minimum land reclaimation height, including of the new airport terminal, was raised from 3 metres to 4 metres. Coastal roads have also been raised.
        
        Adapting to droughts and water shortages
        
        To adapt to more frequent extreme weather events such as droughts, efforts are made to reduce water use, and to increase the efficiency of water usage
        
        Example: Drip irrigation in Israel - Advanced drip-irrigation technology developed by Netafirm ensure timely delivery of irrigation, of the right amount at the right time. Useful in a semi-arid environment
        
        Example: Desalination in Singapore - Building of desalination plants as one of the four national taps. Typically through reverse osmosis. Effective but costly and energy intensive
        
        Adapting to flooding and tropical cyclones (T1.2)
        
        Creation of floodways
        
        To adapt to flooding from more frequent and intense tropical cyclones, floodways can be built to provide and outlet for floodwater
        
        Example: Floodway between Mississippi River and Lake Pontchartain in New Orleans, to adapt to more frequent and intense cyclones from the Atlantic Ocean
    - - 12m
      - 20m
        
        'Adaptation strategies are the answer to climate change'. To what extent do you agree with the statement?
        
        While adaptation strategies may provide immediate relief to the negative effects of climate change that certain locations are already experiencing, several locations and communities, for reasons associated with cost, may find it difficult to emulate certain adaptation projects
        
        Moreover, adaptation strategies - enacted at the local scale - do not provide impactful remediation to climate change - which must be understood to be a transnational/transboundary problem.
        
        Alas, adaptation strategies - unlike mitigation strategies - do not seek to tackle the root cause of the issue (i.e. excessive carbon emission brought about by human activities.
        
        Understanding so, this essay argues that adaptation strategies are the answer to climate change only to a small extent.
- - - - Low level of public spending on road and transport infrastructure
        
        Poor governance, low political will and bureaucracy, and laissez-faire attitude. Lack of resources to build new roads and highways. Delays in building costly mass transit systems
        
        Repeated delays of building MRT in Jakarta. Only succeeded to build one line with a loan from Japan.
        
        Dependency theory - reliance of LDCs on DCs for urban solutions?
        
        11-km Yellow Line in Sao Paulo cost US$1.6 billion to build
        
        Mass transit is too expensive for the urban poor. Thus, the urban poor continue to rely on informal transport on the roads
      - Informal Transport
        
        Unlicensed transport services are cheaper and provide door-to-door services since they do not ply a fixed route.
        
        Tuk-tuks in Bangkok, angkot (minivans) in Jakarta, and pedicabs in many Asian cities
        
        These are preferred among the urban poor as they are cheaper than mass transit systems. Though, it creates congestion due to their slow speed. Also congregate at busy intersections to wait for passengers.
      - Poor Observation of Traffic Rules
        
        Vehicles flout traffic rules and traffic lights. Traffic jams create a gridlock, especially at busy junctions. Animals such as donkeys, camels and cows, and animal-driven carts, roaming the streets of cities in India
        
        Such mixed traffic in Delhi causes delays in movement of traffic. Elephants used to cause traffic congestion in Bangkok, though they have since been banned by the Bangkok Municipal Authority.
    - - Lack of Public Transportation
        
        "Train Pushers" in Tokyo, Japan
      - Concentration of Economic Activities in CBD
        
        Commercial and administrative functions located in CBD
        
        Singapore - shopping, banking, office, hotels, and government buildings located in city centres such as Marina Bay, Shenton Way and Orchard Road.
        
        City centre continues to be attractive for commercial activities despite attempts at decentralisation.
        
        Results in high traffic congestion for trips into the CBD
      - Increase in Urban Sprawl
        
        Definition: Urban sprawl is the spread of an urban area into what used to be the countryside. Associated with the urban concept of suburbanisation, it relates to the expansion of human population away from central urban areas into low-density and usually car-dependent communities.
        
        As more people move to suburbs at the edge of cities, traffic congestion may get worse as these people may see a need to drive their cars into the city centre to get to work. It is compounded by people being brought into city on large roads or motorways. These roads then link up with smaller, older, narrower roads in the city centre. This caues a bottleneck and congestion.
        
        Los Angeles, USA
  - - - Opportunity cost of time wastage - reduces city's economic productivity
        
        DC: Traffic jams cost each US drivers US$1200 a year. In LA, there is an average of 64 hours of delay per year.
        
        LDC: Jakarta - traffic jams cost US$5 billion annuall.y
    - - Spillover effects from main arterial roads to secondary roads and side streets
        
        Affects residential neighbourhoods
      - Inability to forecast travel travel time accurately, leading to more time being wasted on travelling and greater frustation.
        
        LDC: In Bangkok, schoolchildren wake up as early as 5am to get to school on time.
    - - Wasted fuel from idling, accelerating, braking etc increases air pollution and carbon emissions. Leads to respiratory diseases, eg lung cancer
        
        LDC: Beijing - more than 5 million vehicles, which contributes to more than 70% of air pollution. Average life span of Beijing's citizens is said to be reduced by 5-6 years
    - - Municipal authorities need to develop a long-term vision for cities' transport development to prevent being voted out.
        
        DC: Air pollution from diesel vehicles was part of London Mayor Sadiq Khan's election campaign in 2016.
  - - - DC
        
        Limiting Car Population Growth
        
        Road Pricing
      - LDC
        
        Hoy No Circulan Scheme in Mexico City
        
        Road Pricing
    - - DC
        
        Increasing Road Capacity
        
        Alternative Forms of Transport
        
        Encouraging Cycling
      - LDC
        
        Alternative Forms of Transport
  - - - To what extent have strategies to ease traffic congestion in cities been effective?
        
        While these trategies may be theoretically effective especially if they tackle traffic congestion at its root (i.e. consumption/purchase of private vehicles), most of them - in reality - have failed to accomplish so.
        
        Moreover, the ease of traffic congestion is further complicated by development and urbanization trends. Particularly in the context of the developing world, even if strategies may appear to ease traffic congestion in the short term, the often do not do so in the long term.
        
        Alas, to ease traffic congestion may require a fundemental rethinkng of how we plan and organize the city. Strategies to ease traffic organization have not been effective as they often fail to adress the issue at an (urban systems) level
- - - - High consumption levels correlate with intense resource use and waste production.
    - - In its current form, urban metabolism is disruptive of natural cycles, promotes waste and undermines the goal of sustainable urban development.
        
        It is necessary for states to examine the circulatory of urban metabolism - to reduce the accumulation of wastes and the extent of negative impact on environment.
        
        The concept of circular metabolism was first formally discussed by Environmentalist Herbert Girardet.
  - - - Waste sorting
        
        Definition: Waste sorting is the process by which waste is seperated into different elements.
        
        Waste sorting can occur manually at the household and collected through curbside collection schemes, or automatically seperated in materials recovery facilities or mechanical biological treatment systems.
      - Waste segregation
        
        Definition: Waste segregation means dividing waste into dry and wet.
      - Strengths
        
        Sorting and segregating waste serves environmental and economic benefits. Different components of waste have very different properties and grouping them allows for proper and more efficient processing or storage.
    - - Definition: Incineration is a disposal method in which solid organic wastes are subjected to combustion so as to convert them into residue and gaseous products.
        
        This process reduces the volumes of solid waste to 20 to 30 percent of the original volume.
      - Strengths
        
        Incineration is common in countries where land is scarce - as these facilities generally do not require as much area as landfills.
      - Weaknesses
        
        Designed in environmentally unsustainable ways - as the process emits gaseous pollutants.
    - - Weaknesses
        
        Fail to consider the long term
        
        Landfills have the potential to cause pollution and contamination of groundwater and soil through leachate, a liquid substance
        
        Rotting food and other decaying organic waste allows methan and carbon dioxide to seep out of the ground and up inot the air. Methan is a potent greenhouse gas, and can itself be a danger because it is flammable and potentially explosive.
      - Definition: A landfill site is a site for the disposal of waste materials by burial and is the oldest form of waste treatment
      - Strengths
        
        Landfills are often the most cost-efficient way to dispose of waste, especially in countries lacking the economic capacity and with large open spaces.
        
        In addition, landfills gas can be upgraded to natural gas - landfill gas utilisation - which is a potential revenue stream.
    - - Reduce
        
        Definition: It refers to the limiting or reduction of waste produced by an individual.
        
        Able to address the issue from its root cause
        
        Strengths
        
        In limiting the number of purchases and waste, the root cause of waste production - which is consumption is tackled.
        
        Limitations
        
        It is however difficult for individuals to limit his/her number of purchases as the culture of consumerism is so central to our lives.
      - Reuse
        
        Definition: It refers to the reusing of items as much as possible before replacing them.
        
        Strengths
        
        While reusing items can reduce waste consumption
        
        Limitations
        
        It does not seek to tackle the root cause of waste production - which is consumption
      - Recycle
        
        Definition: Recycling is a resource recovery practice that refers to the collection and reuse of waste materials, where the waste materials are reporcessed into new products.
        
        Limitations
        
        Central to the idea of recycling is the notion that waste problems can be resolved, and sustainable urban development promoted through individual behavioral change. Such movement can take our attention off the structural causes of waste production, which is capitalism.
  - - - How effective are different strategies to manage non-hazardous waste in cities?
        
        Theoretically, these strategies can be effective in managing non-hazardous solid waste in cities if they address the root cause of consumption.
        
        However, in reality, most of these strategies do not effectively manage the issue of non-hazardous solid waste as they do not address the root cause of consumption.
        
        In addition, non-hazardous solid waste are mostly ineffectively managed as most strategies fail to consider the long-term.
        
        Alas, waste management strategies are mostly ineffective as they often are designed in environmentally unsustainable ways.
    - - Account for the urban metabolism of countries at high levels of development.
        
        High levels of consumption in countries at high levels of development have contributed to a linear urban metabolism.
        
        Apart from that, the lack of recycling have also contributed to a linear urban metabolism.
        
        However, there are also cities with urban metabolism becoming increasingly circulat.
- - - - Ecological Footprint (EF)
      - Green City Index (GCI)
      - Happy Development Index (HDI)
      - City Development Index (CDI)
      - Genuine Progress Indicator (GPI)
  - - - World Happiness Report
      - Mercer's Quality of Living Ranking
      - EIU's Global Liveability Ranking
    - - Environmental
      - Political
      - Socio-economic