Megacities

Our increasing global population is close to reaching 8 billion! Over half of these people live in a city! Perhaps you live in a city, or you have previously lived in a city. Even if this is not the case, you’ve likely visited a city. But what about a megacity? What is the definition of a megacity? What are their characteristics? And what are some opportunities and problems within megacities?

Megacities definition

Megacities are key in today’s society. In fact, around 60% of the world's population lives in a megacity. They play a large role in economies, not only regional economies but also global economies. Although, there are some social and environmental challenges alongside megacities.

Fig. 1 - An example of a megacity is New York City.

Firstly, it is critical to distinguish the difference between megacities from millionaire cities, meta cities, and world cities.

Characteristics of megacities

The characteristics are the various features that constitute megacities. But what are these major characteristics?

Population

The first major characteristic of megacities is their population size. Megacities have populations of over 10 million. They are ultimately large, urban agglomerations.

Large surface area

Another factor that characterises megacities is their vast surface area. Despite covering a large region, megacities are usually densely populated metropolitan areas that can be found all over the world from Asia, Africa, the Americas, and even the United Kingdom.

Extensive transport system

Transportation is another key element of megacities; many megacities contain multiple methods of transportation. People navigate their way around a megacity by walking, cycling, driving, and using buses, trams and trains, such as metro systems. This is due to the fact the demand for these methods of transportation is so high since the populations of megacities are so large.

Megacities in the world

The first megacities in the world were Tokyo and New York City in the 1950s. However, this rapidly changed, and by 2018, the United Nations stated there were 28 megacities across the world. There are currently approximately 34 megacities in the world. Yet, this number is expected to continue to increase due to the huge, continuous advancement of urbanisation and population growth.

This rapid growth in megacities is due to the range of opportunities provided by megacities, which will be examined later in this explanation. First, let's take a look at some examples.

Examples of megacities

Many megacities can be found all over the world and in both high-income countries (HICs) and low-income countries (LICs.) Below is a list of some of these megacities.

Tokyo

The largest megacity in the world is Tokyo in Japan. The metropolis currently has an estimated population of over 30 million; however, the direct city has an estimated population of 14 million people.

Fig. 2 - Tokyo.

Tokyo has been considered a megacity since the 1950s, making it one of the first-ever megacities. Tokyo is the capital of Japan, allowing it to have various global connections, and therefore economic gain, as well as an excellent transport system. All of these factors make it a suitable megacity.

Opportunities in megacities

As stated earlier, the number of megacities worldwide is seeing a continued increase. This is due to the many opportunities that megacities provide. Let's take a look.

Migration

Rural-to-urban migration is common. People are migrating out of rural areas and into urban areas such as megacities due to a range of push-pull factors. The table below shows the push-pull factors of migration to megacities.

Production

Production is another opportunity presented by megacities. The high population numbers of megacities allow for high levels of productivity, which generates economic advancement. Companies recognise the production opportunities of megacities, placing their research and development teams in HIC megacities and their manufacturing teams in LIC megacities. This allows companies to grow and increase economic revenue.

The globalisation of the economy

There is also a major economic profit from megacities. Megacities have considerable connections worldwide. This allows a more streamlined flow of business universally, which enriches the global economy.

Governance

Megacities are often huge political hubs. Political decisions can be made in megacities as they hold influence and power due to their high population size.

Problems with megacities

Although megacities offer these advantages, there are also issues associated with megacities. The main elements of these problems are environmental and social factors.

Environmental problems

Environmental issues caused by megacities are likely to increase in the coming years.

Ecological footprint

Pollution

Megacities are giant polluters. This is because of their urban setting. Various transportation and work environments, such as industrial practices and energy demand, release high levels of pollutants such as carbon dioxide. Not only do these reduce the air quality of the location, but they also contribute to global warming through greenhouse gas emissions. Consequently, this contributes to climate change.

Social problems

Megacities are home to millions of people, which makes social problems more likely.

Urban sprawl

Urban sprawl is the accelerated expansion of urban areas. This uncontrolled growth occurs in megacities and can lead to issues such as overcrowding and congestion. Due to the various transportation methods in megacities, congestion can become a major issue in megacities, disrupting traffic flows and causing accidents.

Inequality

Megacities, typically acquire high levels of inequality associated with housing, employment, water availability and sanitation.

Housing

Housing availability is an issue in megacities. The rapid growth of megacities increases the demand for housing, which cannot necessarily always be met. This leads to squatting, homelessness, and slum areas.

Fig. 3 - Slum area in a megacity.

Slums are usually found in the developing world and experience high levels of poverty.

Employment

Although employment opportunities are a pull factor for megacities, the rapid growth of megacities means that the number of jobs cannot keep up with the growing population of the megacity. This leaves people without employment. However, there is an opportunity for informal employment in megacities, which includes unskilled labour. Unfortunately, this allows low wages and poor treatment of staff.

Water availability and sanitation

Water availability and sanitation can become an issue in megacities. Due to the high demand for megacities, ensuring access to water for everyone in a megacity is particularly difficult, especially in slum areas. This can cause people to pick up water bourne diseases from poor-quality water.