3.1.1. Megacities

In 2018 'World Urbanisation Prospects' the UN identified very large cities with populations over 10 million as 'Megacities' and UN further enlisted 33 megacities of which half of these urban agglomerations are in India and China and 27 are in the developing regions of the world, termed as the 'global south'. Globally, this is projected to rise to 43 by 2030, and the number of cities with 1 to 5 million inhabitants is projected to grow to 597.

Megacities are defined as urban areas with populations exceeding 10 million people. According to the United Nations, as of 2018, there were 33 recognized megacities, with a significant concentration in developing countries like India and China. This number is expected to increase to 43 by the year 2030. Additionally, cities with populations between 1 to 5 million are also anticipated to increase significantly, indicating a trend of rapid urbanization in these regions.

Think of megacities as bustling beehives. Just as bees contribute to the colony's growth and productivity, a large population in megacities drives economic development and innovation, but also brings challenges like congestion and pollution.

The characteristics of a Megacity are; size, rate of growth, and complexity in terms of administration and infrastructure (Wenzel et al., 2007), and are the economic drivers of the country.

Megacities possess distinct characteristics that include their large size, rapid growth rate, and intricate infrastructure and administrative systems. They serve as critical economic engines for their countries, influencing national economies through their sheer scale and capacity for innovation. The complexity of managing such a vast urban population demands sophisticated governance and infrastructure planning.

Imagine managing a large festival. The more people that attend, the more complex the logistics become—food, restrooms, security, and transportation must scale up and work seamlessly together. Similarly, megacities require adept management of various systems to sustain their large populations.

The urban population is projected to increase up to 28% worldwide, while rural population is projected to fall to 40% by 2030 (UN, 2018). Tokyo, Delhi, and Shanghai ranked 1st, 2nd, 3rd back in 2018 has already been overtaken by Shanghai, Chongqing, Beijing, and Guangzhou, ranking Delhi at 5th today.

By 2030, the global urban population is expected to rise significantly, while rural populations decrease. For example, the cities of Tokyo, Delhi, and Shanghai were among the largest in 2018, but as urbanization progresses, cities like Chongqing and Guangzhou have moved ahead, indicating the rapid changes in population distribution and growth dynamics in megacities.

Think of it like a race; once a few runners (cities) start to pick up speed, they can quickly move past others. With increasing urbanization, some cities are ‘gaining speed’ in population growth, overtaking others that were once considered the largest.

Li, et al. (2019) analyses four major problems of Megacities from urban geography and ecology perspective, as follows;

• Land subsidence due to overexploitation of groundwater.
• Environmental problems such as pollution, urban heat islands, urban air quality and haze, carbon emissions and dust storms, etc.
• Traffic congestion, parking difficulty, public transport. This is closely related to the above problems of pollution, haze, etc.
• Energy consumption and production that is inefficient and unsustainable.

Megacities face several formidable challenges including land subsidence from excessive groundwater extraction, environmental pollution, severe traffic congestion, and unsustainable energy consumption. These issues can lead to deteriorating living conditions and pose risks to public health and safety, necessitating urgent local and global responses.

Think of a sponge that’s being squeezed water from all sides; if overused, it collapses under pressure. Similarly, megacities stretch their infrastructure and resources thin, leading to significant urban challenges that require careful management and innovative solutions.

High-risk cities face population decline and loss of life due to geographical location, mostly coastlines, and consumption patterns vulnerable to natural disasters such as cyclones, floods, droughts, earthquakes, landslides, and volcanic eruptions.

Megacities located near coastlines or in geologically active regions are particularly susceptible to natural disasters. Rapid population growth combined with inadequate infrastructure may exacerbate the impact of such disasters, leading to severe ramifications for human life and livelihoods.

Consider how a sandwich filled to the brim can easily collapse if it’s suddenly dropped. Similarly, megacities that are densely populated and poorly prepared for emergencies risk severe consequences when natural disasters strike.

The mass movement of population from rural to urban has led to drastic changes in constructed habitats and has put ever-increasing demands and stress on infrastructure, limited resources, and inequitable access, and deteriorating living conditions, leading to a large chunk of the population to be below poverty line and without social welfare.

As people migrate from rural areas to megacities seeking better opportunities, the demand for infrastructure and resources increases drastically. This often results in inadequate access to essential services and contributes to urban poverty and substandard living conditions, illustrating the complex socio-economic dynamics at play in these large urban centers.

Imagine inviting more guests than your party can accommodate; the result is overcrowding, chaos, and some guests left wanting. Likewise, megacities face a challenge when their infrastructure struggles to support an influx of residents, leading to scarcity of services and increased inequality.

While cities today approximately occupy only 2% of the total land, it contributes towards 70% of the GDP and is responsible for 60% global energy consumption, 70% greenhouse gas emissions and 70% global waste generation.

Despite occupying just a fraction of the earth's land, megacities have a powerful economic footprint, contributing a significant portion to global GDP. However, they also bear a disproportionate share of the world's energy consumption, emissions, and waste generation, raising critical questions about sustainability and resource management.

Think of a powerful machine that can produce a lot but generates a lot of waste and consumes excessive energy; such is the paradox of megacities—they are centers of economic power but also sources of significant environmental strain.

To combat these challenges, the ‘New Urban Agenda’ was adopted during the UN Conference on Housing and Sustainable Urban Development (Habitat III) in 2016...

In response to the challenges faced by megacities, global frameworks such as the ‘New Urban Agenda’ have been established to guide sustainable urban development. These guidelines encompass everything from urban planning to resource management, emphasizing the integration of digital technologies to improve living conditions.

It’s like creating a blueprint for a complex building; without a solid plan, the structure might collapse. Similarly, the New Urban Agenda acts as a strategic template guiding megacities towards sustainability and resilience in the face of existing challenges.

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