Megacities and Climate Change

As the population of world has increased, so has the population density of cities, so much so that a term has been coined to denote cities of more than 10 million inhabitants: megacities. There were 33 megacities in the world as of 2018, but the number might increase to 43 in 2030. [1] However, the emergence of megacities has not only come on the heels of climate change but also made them more vulnerable to the consequences of climate induced disasters, and within cities, their marginalized populations more so. Making cities sustainable, resilient, safe, and inclusive is part of the 2030 Agenda for Sustainable Development. Every step taken in the wrong direction is antithetical to the planet’s sustainability. This article explores some causes and consequences of climate change in the megacities. In addressing the causes lies the solutions too, if only the policymakers pay heed to them.

Firstly, not all regions of the world will be equally affected by climate change. Twenty-seven of the world’s 33 megacities are located in the global south, which already faces a plethora of challenges and security threats. Dhaka, which is just meters above the sea-level, has one of the lowest adaptive capacities to climate change, and is extremely susceptible to the impacts of climate change, too.[2] Floods have become an annual occurrence in Mumbai. [3] Lahore and Karachi, two megacities situated in Pakistan, which struggles with its economic sector already, have the largest and the second largest settlement areas exposed to flooding.[4] Owing to the size of population in megacities, they not only threatened by typhoons, but smaller storm could inflict huge losses. [5]

Megacities are also economic hubs, which also contributes to green-house emissions if the industries rely on burning coal for energy. Delhi, a smog-stricken city, is expected to be the biggest megacity when its population size takes over Tokyo’s. It has the highest number of small-scale industries, which are said to contribute 19% to the pollution in the city.[6]

One of the defining characteristics of megacities is commuting patterns, which is also one of the culprits that cause pollution and climate change. Lahore faces acute crisis of public health spawned by its seasonal smog and also a high risk of heat waves in the summer season.  It witnessed the worst smog for three consecutive days in 2023, bringing the city to a standstill for some days and giving its residents a flashback to COVID-19-induced measures.[7] Studies have found link between increasing smog and climate change, too.[8] In case of Lahore, a major contribution of smog is transportation, but the city still does not a public transport system that caters to its population’s needs. But having a public transport system is not enough; One study conducted in Delhi suggested that public transportation and other modes of non-motorized transportation need to be made more convenient and safer to reduce to car-ownership and usage. [9] To sustain the food requirements of the population of megacities, a large amount of goods have to be transported into the cities, thereby increasing the ecological footprint. [10] Thus, local production of food should be preferred.

Waste materials, such as food waste, industrial waste, and municipal waste, are another major source of greenhouse emissions, especially in megacities. Due to the higher comspumtion levels in megacities, enormous waste is produced as well, which is neither properly collected nor disposed of.[11] To begin with, steps should be taken so that less waste is generated, for example, minimizing non-recyclable materials. As global food waste amounts to 1.3 billion tones every year, surplus food should be shared with the poor through food banks. [12] Levying waste tariffs and penalizing higher waste production can help in decreasing the waste, as well.[13]

Climate change is not an isolated issue but is accompanies by several traditional and non-traditional security issues. Poverty, rate of crime, water scarcity are also going to rise. It is crucial that governments focus on strategies to mitigate pollution in megacities. Under the Paris Agreement, the signatories are to share their Nationally Determined Contributions (NDCs), which outline their measures to combat climate change by reducing their emissions and adopting adaptation plans. Japan rolled out its Zero Emission Tokyo Strategy in 2019 to tackle CO2 emissions which comprised of various targets related to energy sector, urban infrastructure and more. [14] Other countries could follow suit and make cities-specific climate policies. World Bank Group’s Country Climate and Development Report for Pakistan also called for the adoption of climate lens while strengthening urban development and provision of services for the major cities. [15]

All in all, by 2070, climate change-induced storms could result in a loss of up to 35 trillion dollars in assets in Asian megacities.[16] Thus, the developing countries are grappling with the dilemma of achieving economic development or clean air; the former is required to gain a higher position in the comity of nations but to achieve the latter, they have to transition to clean energy sources, for which they don’t have the capacity compared to other states. [17] The economic luster of megacities can be greatly endangered by the lackluster climate policies of the governments. It is also imperative to remember that the developed countries are the biggest contributors to green-house has emissions, and their economic progress has come at the expense of the countries in the South. Thus, they need to pay their due share in ensuring climate justice. The setting up of Loss and Damage fund at COP 28 is a step in the direction of climate justice, but continuation in the contributions to it must continue. Also, all countries must agree to phase out coal in the near future. Otherwise, the future of humanity itself would be in deep waters, literally.

[1] United Nations, 2018, The World Cities in 2018, https://digitallibrary.un.org/record/3799524?ln=en. 

[2] World Wide Fund for Nature, 2009, Mega-Stress for Mega-Cities: A Climate Vulnerability Ranking of Major Coastal Cities in Asia. 

[3] Casey, Alex. “Megacities, Megarisks: How Population Growth and Climate Change Increase Vulnerability in the World’s Largest Cities.” Population Connection, 24 May 2022, populationconnection.org/blog/megacities-population-growth-climate-change/. 

[4] World Bank Group, 2022, Pakistan Country Climate and Development Report. 

[5] Poon, Linda. “Climate Change Is Testing Asia’s Megacities.” Bloomberg.Com, Bloomberg, 9 Oct. 2018, www.bloomberg.com/news/articles/2018-10-09/are-typhoons-getting-too-strong-for-asia-s-megacities. 

[6] Dykes, Jacob. “Attempts to Clean New Delhi’s Air Are Failing Without a Radical Change in Energy Policy.” Geographical, 20 May 2022, geographical.co.uk/climate-change/new-delhi-air-pollution-capital-of-the-world. 

[7] Hussain, Abid. “In Lahore, It’s That Toxic, Smoggy Time of Year Again.” AlJazeera, 11 Nov. 2023, www.aljazeera.com/news/2023/11/11/in-lahore-its-that-toxic-smoggy-time-of-year-again. 

[8] Haider, Fatima. “Climate Change and Smog: A Vicious Cycle in Lahore.” Stratheia, 29 Nov. 2023, stratheia.com/climate-change-and-smog-a-vicious-cycle-in-lahore/. 

[9] Mohan, Dinesh, and Geetam Tiwari. “Mobility, environment and safety in megacities: dealing with a complex future.” IATSS research 24.1 (2000): 39-46.

[10] Folberth, Gerd A., et al. “Megacities and climate change–A brief overview.” Environmental pollution 203 (2015): 235-242.

[11] Delzeit, Ruth & Weitzel, Matthias. (2011). Reducing the water and waste footprints of megacities.

[12] “Why Cities Need to Advance Towards Zero Waste.” C40 Knowledge Community, Mar. 2023, www.c40knowledgehub.org/s/article/Why-cities-need-to-advance-towards-zero-waste?language=en_US. 

[13] UN-Habitat, 2021, Cities and Pandemics: Towards a More Just, Green and Healthy Future, https://unhabitat.org/cities-and-pandemics-towards-a-more-just-green-and-healthy-future-0. 

[14] “Zero Emission Tokyo Strategy.” C40 Cities, 18 Mar. 2022, www.c40.org/case-studies/zero-emission-tokyo-strategy/. 

[15] World Bank Group, 2022, Pakistan Country Climate and Development Report. 

[16] Wallace-Wells, David. The Uninhabitable Earth. Penguin Books, 2019.

[17] Dykes, Jacob. “Attempts to Clean New Delhi’s Air Are Failing Without a Radical Change in Energy Policy.” Geographical, 20 May 2022, geographical.co.uk/climate-change/new-delhi-air-pollution-capital-of-the-world.