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Middle Eastern Cities in a Time of Climate Crisis

 | 
Agnès Deboulet
, 
Waleed Mansour

Part II. Paths for De-carbonization and Biodiversity Recovery

Planning Megacities Facing Climate Change

Eric Huybrechts

Entrées d'index

Texte intégral

Introduction

1Megacities are facing major contemporary challenges, including climate change, migration, health crises, the energy transition, disruptive technologies, socio-spatial segregation, socio-economic inequalities and territorial governance crises. Climate change adds difficulties to tackling these challenges in a context of unprecedented levels of institutional complexity. Vulnerabilities related to climate change, such as flooding, sea submersion, landslides, soil movements, water scarcity and heatwaves, put pressure on how to manage territories. Megacities become responsible for mitigating greenhouse gas (GHG) emissions because of their large energy consumption. Accordingly, spatial planning should change dramatically to tackle mitigation and adaptation issues in the face of climate change. The governance structures of megacities cover territories of different scales, depending on their position in terms of economic development, physical agglomeration, organization of services, land and property markets and environmental protection. They are subject to levels of complexity that require reinventing their management methods to manage crises.

  • 1 Beijing, Bogota, Buenos Aires, Delhi, the Eurodelta region, Gauteng, Istanbul, Jakarta, Kinshasa, (...)

2The main purpose of the present article is to discuss the challenges to and solutions for planning megacities facing climate change. It is based on shared experiences of an international working group dedicated to this topic, managed by the Metropolitan and Territorial Planning Agencies (MTPA) global network in collaboration with UN-Habitat’s MetroHUB, Metropolis, ICLEI, C40 and Metrex. This working group gathers a dozen megacities,1 sharing their practices following the territorial planning shift due to climate change, and is preparing statements on the planning solutions proposed by megacities.

Megacities Facing Climate Change

  • 2 By 2030, the twelve largest conurbations in the world would be, in decreasing order, Delhi, Jakart (...)

3Climate change has different effects on each megacity, depending on a its geography and vulnerabilities. Of the thirty-four megacities that are home to one-eighth of the world urban population (UN-DESA 2019), most are located on seashores and along rivers or big lakes. With the exception of Tokyo, all these megacities are growing. Some of them are growing very rapidly, such as Delhi or Kinshasa, with 850,000 additional inhabitants a year.2 The more these cities expand, the more they increase their vulnerabilities. According to some extrapolations (Hoornweg and Pope 2017) based on the World Urbanization Prospects 2018 Revision (UN-DESA 2019), there will be fifty megacities in 2050 and eighty-three in 2100, with over two billion inhabitants altogether. Megacities can be considered a main feature of twenty-first-century human settlement. The twenty-first century is therefore not only the century of metropolises but also the century of megacities. How do these contemporary artefacts face climate change?

4The term ‘megacity’ refers to population size (over ten million inhabitants), but the definition presents problems for making comparisons when population and job statistics are based on administrative definitions that differ from one country to another. If we consider a megacity to be a functional urban area (OECD 2012), permanent changes in the built-up area and in economic and mobility areas add obstacles to the delimitation of a megacity. If we consider the administrative side of governing such large concentrations of people and activities, institutional arrangements generally do not correspond to the size of the functional urban area and the related economic and mobility areas. For example, Greater London, with its nine million inhabitants, is smaller than its economic and mobility area of fifteen million inhabitants. Consequently, international comparisons are difficult to make, and researchers generally use proxies based on administrative limits that approximately correspond to their purpose, i.e. urbanization, economic development and mobility, natural resources management, pollution, environmental vulnerabilities, social and spatial inequalities and governance, among others. Assessing vulnerabilities of megacities facing climate change depends on the definition used, which will affect the area to be considered for flooding risks and the related population and activities exposed to these risks.

5Megacities are widely recognized as catalysts for globalized, national and international economies. They are part of an interconnected global city network (Sassen 1991). The current shift in the globalization process will probably affect the position of megacities in the international competition between territories. The energy crisis will affect the mobility system of large cities. Facing multiform and frequent crises, their development pattern is being questioned. Their strengths lie in their connectivity, labour market flexibility, innovation, cosmopolitan societies, financial capacities and very large consumer markets. But the concentration of populations makes them vulnerable to air, water and soil pollution, traffic congestion, social and territorial inequalities and environmental crises. And climate change increases these vulnerabilities. Due to their importance for countries, megacities have large responsibilities vis-a-vis contemporary challenges and for offering solutions. Facing climate change, they should reinvent the way they plan and manage their territories.

  • 3 Gauteng province accommodates fifteen million inhabitants within two major cities, Johannesburg an (...)

6Megacities highlight important contradictions of the contemporary territorial pattern. Globalization, liberalization of the economy and competitiveness increase social and economic inequalities, with a higher concentration of wealth in the hands of a few: the Gini indexes of New York, Sao Paolo, Buenos Aires and Gauteng province3 are above 0.50 (UN-Habitat 2020). City marketing is devoted to attracting investment and talents to compete with other large cities in the world, resulting in the massive eviction of populations from central parts of cities to provide space for real estate investment. The finance economy mainly affects the more profitable real estate assets and urban services of megacities. It fosters gentrification and increases spatial segregation and the polarization of urban development. Empty apartments (20 per cent in China, mainly in megacities) and new ghost towns (Cairo has several) mobilize large investments without benefits for the population. This casino economy affects GHG emissions directly, with cement, steel, sand, gravel, energy and water taken from the natural environment and producing GHG emissions for empty real estate without consideration for social needs.

7We can make a distinction between megacities of developed countries, which are very powerful, mainly planned and well integrated into the world economy, and the megacities of the developing world, whose core parts are well integrated into the world economy but whose remaining parts appear to be less well integrated, informal and unplanned. The population of megacities in the Global North is growing slowly, while that in the Global South is growing fast. Because of their size, their spatial structure is becoming polycentric. Their centres are being densified while at the same time, urban extensions create new subcentres to provide nearby services and jobs. Cairo, Lagos and Dhaka are unable to manage rapid urbanization in spite of large investments in infrastructure and new towns.

8The impacts of climate change differ between the city centre and the suburbs. The heat island effect is greater in the city centre, where a higher difference in temperature is present. The increasing impermeability of the soil at a large scale, due to urban expansion, increases the effect of flooding by concentrating water flows. Urban extensions put more inhabitants in areas prone to risk, especially in terms of flooding but also landslides and soil movements. And most megacities are located on seashores, meaning they will be badly affected by the rise in sea level in the future.

Difficult Management of Crises

9Climate change is becoming one of the main challenges megacities are facing. Several are preparing projects to face flooding, sea submersion, heatwaves and other consequences. The issues faced by megacities are amplified and complex; they represent a considerable challenge for governments and local authorities in terms of management, governance and territorial planning.

10One of the distinctive features of megacities is the expansion of urbanized areas beyond the administrative boundaries of the central city or even the region of the main urban agglomeration. In fact, modes of governance are often extremely fragmented by vertical and horizontal divisions between the different levels of government – national, subnational (regional/metropolitan), local (district/municipal/neighbourhood) – in addition to the functional fragmentation of ministries, sectoral fragmentation (water, energy, transportation, housing, health, education, environment etc.) and territorial fragmentation (urban, peri-urban and rural areas). In some cases, this fragmentation can lead to the selective governance of issues and megapolitan spaces according to a spatial division and territorial basis. These complex systems of governance mobilize multilevel and multiactor dimensions to devise and implement territorial policies and strategies. In fact, there is no unified version of the territory; instead, there are different strategies, programmes and initiatives with multiple arrangements articulated around strong and sometimes antagonistic political wills. Multilevel, intersectoral and interterritorial governance takes different shapes in different sectors (water management governance is different from transportation governance or energy governance). The fragmentation of governance systems hinders coordination, which is necessary to limit the impact of natural disasters with their cross-sectoral effects. The more complex governance is, the less efficient it is.

  • 4 Region Ile-de-France, eight Departments, Métropole du Grand Paris (covering 5 per cent of the mega (...)

11Tentative experiments have been carried out to unify governance at the scale of the megacity. Beijing is one municipality with twenty-two million inhabitants. Greater London adopts a unified system with a strong representation for an elected mayor. New York does not have a megacity political entity: it extends across three states and more than 800 municipalities. The Paris region covers 70 per cent of the megapolitan area and 95 per cent of the population, but the extreme territorial fragmentation4 makes it one of the most complex territorial governance systems in the world. In fact, the institutional sovereignty of the megacity is rarely at the scale of the functional urban area. Therefore, what real capacity do various governance models have to consider the social, economic and environmental challenges facing megacities, especially regarding climate-change adaptation and the management of environmental crises? Despite greater economic resources and political capacities more powerful than those of other cities in the same country, fragmentation weakens megacities’ ability to face climate crises. This challenge requires specific governance and coordination mechanisms.

12Tensions between the core part of the agglomeration and its peripheries are inherent to large-city management. A powerful central municipality such as Rio de Janeiro, Jakarta or Moscow (which accommodate half the population of their functional urban area) hinders the implementation of a balanced sharing of power and capacities between municipalities. Peripheries suffer from having fewer financial capacities and poorer access to high-quality infrastructure and facilities, a situation that creates inequalities between centres and peripheries. Core parts of megacities can be well equipped to inform the population and take protection measures when a disaster is announced, like in Rio de Janeiro, but this is not the case for most peripheries. The extreme governance complexity of megacities throws into question their capacity to face the challenges of climate change. Their economic and innovation capacities are exceptional, but their governance makes them very fragile in driving their development towards better adaptation and mitigation due to climate change. New frameworks for thought and action are necessary. In this context, territorial planning agencies play a strategic role as decision-making, supportive tools for their partners. They become mediators, provide knowledge to feed public debate and devise and monitor megapolitan policies and strategies.

Climate Change and Resilience

13Due to their size and their development pattern, megacities considerably increase GHG emissions. In 2018, Environmental Research Letters estimated that the 100 most populous cities accounted for 18 per cent of global emissions. The dynamics of urban sprawl as well as the use of individual motorized vehicles increase congestion and public health problems. Artificialization of the soil linked to the emergence of these large urban areas also contributes to the reduction of biodiversity on a global scale. These cities’ ecological footprint is much larger than their surface areas. London ecological footprint is over a hundred times its surface area, for example (Stats, Maps n Pix 2020). The environmental impact of global warming is amplified in megacities, which are gradually becoming aware of their vulnerability.

14Megacities are in the frontline to manage acute crises: air pollution, floods, pandemics, etc. Paris, Mexico, New York, London, Tokyo, Seoul, Bogota, Rio de Janeiro and Lima, among others, are adopting GHG reduction strategies to achieve the ambitious goal of carbon neutrality. Initiatives are multiplying in many different areas through various means (green growth, eco-mobility, ‘no net land take’, net zero GHG emissions, etc.). They share experiences and experiment with new concepts and innovative projects. But there is a long way to go before a more resilient megacity model is achieved.

15The geology, topography, hydrography and location of cities play an important role in the significance of natural risks. As a result of climate change, Dhaka, Lagos, Shanghai, Manila, Guangzhou, Tokyo, Karachi, Rio de Janeiro, Mumbai, New York and other cities are facing rising sea levels and coastal erosion and are at risk of submersion. The intrusion of salt water into the soil and groundwater has consequences such as the destruction of agricultural crops and concrete. The vulnerability of coastal megacities is also increased by the rapid increase in inhabitants living in flooding-prone areas, as well as by the large-scale informal exploitation of the water tables on which these cities (Bangkok, Jakarta and others) were built.

16Megacities are mobilized to urgently respond to risks and at the same time prepare long-term actions. Urban planning has to become more resilient and sustainable. Some countries, such as Brazil, have adopted national protection and civil defence measures based on an information and monitoring system for natural disasters. A social, economic, environmental and spatial analysis was crucial to locating the most vulnerable areas and populations. Coordination between different administrations and operators (telecommunications) is essential to anticipate disasters and inform the population in due time. The innovative mechanism developed by Rio de Janeiro has resulted in the adoption of a national plan for the management of and response to natural disasters.

17The recent health crisis has led to doubts about the capacity of megacities to overcome longer-term crises in terms of their urban morphology (size, shape, structure, density, centralities), temporalities (concentration at peak hours and in large facilities) and organization of work (teleworking, schedules, teams, commercial and office real estate), including its consequences for residential mobility and behaviours (social distancing, teleworking, telemedicine, e-shopping, residential strategy and public spaces). Territorial planning is dramatically questioned in relation to climate, energy, behaviour and technological transitions in post-COVID-19 times. The health crisis offers opportunities to accelerate changes that are beneficial for adapting megacities to climate change. We can already see that in some megacities, the priorities of local and regional authorities have changed, with an acceleration of the implementation of soft mobility projects (cycling routes) to reduce GHG emissions, a better appreciation of the importance of green public spaces to cool the cities and a reconsideration of the way in which housing is designed in order to face future crises.

Mitigation in Mobility and Transport

18Most megacities face higher degrees of congestion, pollution and energy consumption than other cities. Levels are extreme in Delhi, Karachi and Dhaka and Tehran. Urban mobility systems are one of the main causes of these negative externalities, especially in megacities where the level of motorization is high and the car is the main mode of transportation. Crises are times for a paradigm shift. The COVID-19 pandemic has had a profound impact on transport and urban mobility. Megacities have taken measures (notably teleworking) to reduce overcrowding on public transport in order to limit the spread of the virus. These restrictions have had the effect of considerably limiting the use of public transport and, despite recent measures in terms of both health and distance between passengers, changes in behaviour appear to have impacted passengers’ use of this mode of transportation, which dropped during this period. While megacities cannot be efficient without mass transportation systems (train, metro), changes in the mobility behaviour and social organization that have occurred can change the way in which urbanization at a large scale is managed.

19Several cities have already introduced new facilities for cyclists and pedestrians. In the Paris region, this has resulted in an additional 650 kilometres of cycling highways to be implemented, while in New York, 100 miles of social and recreational streets were added and in Bogota, temporary facilities widening pavements and cycling paths at the expense of underused traffic lanes were implemented. Initiatives such as these support a gradual transformation of the road network on a metropolitan scale. Examples include metropolitan avenues in Seoul, Paris, New York, Rio de Janeiro or Bogota that have replaced motorways. Some motorways have been replaced by pedestrian avenues (Paris’ riversides, for example), changing the quality of life and image of the city. The potential reduction in motorized mobility, linked to the economic slowdown, the significant use of teleworking and the massive modal shift are interesting signals on the modal shift that already occurred in several megacities after reaching ‘peak car’.

20Several megacities have recently supported Paris’ approach of the ‘fifteen minutes city’ project: a city where, in less than fifteen minutes, residents can access essential services, green spaces and employment. The aim is to bring residents’ demand closer to the offer and ensure functional diversity by developing social, economic and cultural interactions. This project also implies integrating a new approach to urban density while increasing the number of meeting and mixing spaces. The reappropriation of this not-so-new concept led to the discovery of new tools for its implementation, with urban services optimized by digital technology and collaboration and sharing practices made possible by the development of digital platforms. These developments involve new approaches that make it possible to reinvent mobility spaces and rediscover new proximities. The approach should be completed with the ‘thirty minutes megacity’, based on a polycentric pattern. Furthermore, mobility policies stimulated by temporary experimentations during lockdown or transformations with a highly symbolic charge have met with some success in the heart of megacities and are extended in the peripheries. The mobility pattern shift contributes to reducing GHG emissions by reducing mobility needs.

Megacities’ Achievements in Terms of the Sustainable Development Goals

21Megacities are the result of the globalization development pattern. Their gigantism makes them difficult to govern and amplifies vulnerabilities. They are not planned as megacities, but territorial planning supports coordination arrangements and attempts to offer better opportunities for prosperity and limit negative externalities. Disruptive technologies can offer new opportunities for public participation, integrated planning, infrastructure management, mobility and work management that will impact megacities at a large scale. But their crucial role as leaders of global development and large responsibility for tackling contemporary challenges make their management one of the biggest challenges of the twenty-first century.

  • 5 For example, PRACC Ile-de-France, adopted in October 2022, with one billion euros of public invest (...)
  • 6 Cities include New York, Los Angeles, Mexico, Sao Paolo, Seoul, Buenos Aires, Tokyo and Moscow.

22Most megacities are adopting climate plans,5 programmes and strategies to reach carbon neutrality in 2050 and implement projects in different fields, such as renewable energy, eco-mobility, bioclimatic renovation, bio-sourced materials, water recycling and urban canopy. They claim their alignment with the New Urban Agenda (UN-Habitat 2016) and the UN’s Sustainable Development Goals (SDGs) through Voluntary Local Reviews or SDG implementation strategies.6 Their policies have at their core the reduction of inequalities, the tackling of climate change, the promotion of sustainable and resilient cities and access to affordable housing and urban services for all.

23While megacities are the main tools of the globalized world and lead the global economy, they have not been able to change the interrelated system that is the result of national policies and international strategies of coalitions of actors. But they prove their ability to provide mitigations paths through innovative solutions in territorial policies that require extraordinary coordination within the complex system of actors. The climate change challenge appears to be an opportunity to change the paradigm for managing and planning megacities.

Bibliographie

Hoornweg, Daniel, and Kevin Pope. 2017. ‘Population Predictions for the World’s Largest Cities in the 21st century’. Environment and Urbanization 29, no. 1: 195–216.

OECD (Organisation for Economic Co-operation and Development). 2012. Redefining Urban, A New Way to Measure Metropolitan Areas. Paris: OECD Publishing. https://www.oecd.org/regional/redefining-urban-9789264174108-en.htm .

Sassen, Saskia. 1991. The Global City: New York, London, Tokyo. Princeton, NJ: Princeton University Press.

Stats, Maps n Pix. 2020. ‘Visualising Ecological Footprints’. February 15. http://www.statsmapsnpix.com/2020/02/visualising-ecological-footprints.html.

UN-DESA (United Nations Department of Economic and Social Affairs). 2019. World Urbanization Prospects. The 2018 Revision. New York: United Nations. https://population.un.org/wup/publications/Files/WUP2018-Report.pdf.

UN-Habitat. 2016. New Urban Agenda. Quito: UN-Habitat. https://habitat3.org/wp-content/uploads/NUA-English.pdf.

UN-Habitat. 2020. World Cities Report 2020: The Value of Sustainable Urbanization. Nairobi: UN-Habitat. https://unhabitat.org/sites/default/files/2020/10/wcr_2020_report.pdf.

Notes

1 Beijing, Bogota, Buenos Aires, Delhi, the Eurodelta region, Gauteng, Istanbul, Jakarta, Kinshasa, New York, Paris and Sao Paolo.

2 By 2030, the twelve largest conurbations in the world would be, in decreasing order, Delhi, Jakarta, Tokyo, Shanghai, Dhaka, Cairo, Mumbai, Beijing, Mexico City, Sao Paulo, Kinshasa and Lagos.

3 Gauteng province accommodates fifteen million inhabitants within two major cities, Johannesburg and Pretoria. It works like a single megacity.

4 Region Ile-de-France, eight Departments, Métropole du Grand Paris (covering 5 per cent of the megapolitan area), sixty-four unions of municipalities and 1,268 municipalities.

5 For example, PRACC Ile-de-France, adopted in October 2022, with one billion euros of public investment from Paris/Ile-de-France Region for the climate.

6 Cities include New York, Los Angeles, Mexico, Sao Paolo, Seoul, Buenos Aires, Tokyo and Moscow.

Auteur

Eric Huybrechts is an architect and urban/regional planner. He started his career as a member of the Greater Cairo team of the General Organization for Physical Planning. Over the last thirty years, he has worked at the Institut Paris Region, the urban planning and environment agency of Ile-de-France, and the French Ministry of Foreign Affairs. He is currently the Manager of European and International Affairs of the Institut Paris Region, working on the urban planning of the great metropolises in the world.

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