by Isabel Wetzel and Junnan Mu.

When talking about ‘Greener Cities’, we are referring to a sustainable urban future, an opportunity of allowing our next generations to have an environmentally sustainable habitat, to live with sustainable infrastructures and clean energy, and to embrace a lifestyle that is in harmony with nature and society. In this future, blue sky, fresh air, and clean water is not a luxury, but a given fact to which everyone on this planet has equal access.

As UN-Habitat’s 2016 World Cities Report rightfully states, our current urbanization model is unsustainable in many respects1. The pattern of urbanization needs to change in order to better respond to the challenges of our time, to address issues such as climate change, informality, and urban expansion and sprawl. Not only our urban form is unsustainable; we have also developed unsustainable lifestyles over time, which need to be addressed equally in order to achieve greener, healthier and more resilient cities. Hereunder, we will be addressing three large contributors of unsustainability to our cities today.

The vicious cycle of waste

Globally, waste volumes are rapidly increasing, even faster than the rate of urbanization. Currently, world cities generate about 1.3 billion tonnes of solid waste per year. This volume is expected to increase to 2.2 billion tonnes by 2025.2 The largest producers of the world’s total garbage are megacities in the global north. However, these numbers do not take into account the cities’ disposal abilities: If there was more data available on the rates of waste generation and disposal, most cities in the global south may add significantly to these numbers. Additionally, the absence of comprehensive policies for urban waste collection, disposal and processing poses immense challenges around the world.

Some forms of waste are visible, but others less so. They are hidden in processes of waste disposal or treatment, but also in consumption patterns; they are byproducts of cities’ economic development based on fossil fuels such as oil, coal or gas. Among them, the most significant one is greenhouse gas emissions. According to reports by UN-Habitat, cities account for a staggering 70 percent of greenhouse gas emissions despite occupying only 3 percent of the Earth’s land surface 3,4

The emission of greenhouse gases result in global climate change, posing serious risks to eco-systems, biodiversity, and vulnerable population groups. It threatens livelihoods of many individuals who will face displacement among other climate-related challenges.5

Unsustainable consumption patterns

Meanwhile, the consumption and production of resources as well as the production of waste have dropped into a seemingly irreversible loop. Urban areas concentrate economic activities, households, industries and infrastructures that are hotspots for resource consumption: Cities consume roughly 75 percent of all natural resources while continuing to produce immense amounts of waste.

This number will increase as the population grows. In order to bring a sustainable equilibrium to this pattern, many changes are required: one is related to the lifestyles of our population, switching to more environmentally friendly practices in our day-to-day lives, such as diverting to more sustainable goods and resources, and improving individual recycling. Another is linked to necessary policy changes that will pull our societies to the much needed transformational shift.

High dependency on unsustainable urban transport patterns

Our current mode of urban transportation and mobility are negatively affecting our climate. Transportation has proven to be a great challenge to the environment as it largely depends on oil. In many countries of the world, the numbers of private vehicles are increasing due to rising income levels. Rather than incentivizing populations to use public or non-motorized transport, many governments support construction of newer, wider roads, adding to the vicious circle of unsustainability.

Many cities have started initiatives such as congestion charges; however restricting movements or increasing prices will only have a minimal impact on the overall private vehicle dependency. Unsustainable transport also has a significant impact on air quality, one of the leading causes of premature disease and death.6

Most sources of urban air pollution are well beyond the control of individuals and demand action by cities, as well as national and international policymakers to promote cleaner transport, more efficient energy production and improved waste management. Many cities are starting to take action to reduce their air pollution levels through data monitoring, creating a benchmark for improvements.

An overlooked global challenge becomes an opportunity

Each of the topics above, if not addressed properly, will cause environmental degradation which is among the major obstacles to sustainable development worldwide.7 Yet, challenges oftentimes also pose opportunities: To reverse the negative impact of the above challenges, it is crucial for local and national governments to take an integrated and systematic approach to mitigate environmental threats that cities face.

Previously applied methods and analyses did oftentimes not achieve the best results. In the past, for example, the important connection between urban planning, provision of basic services and the environment had largely been unattended. Focusing only on one issue at a time, and not considering the multi-dimensional scale of many urban issues only exacerbated the problems. This is why tackling the urban environmental problems always needs to go hand in hand with considerations for urban planning and design, legislation and economy.

Greener Cities are part of the solution

There is an increasing awareness of using cross-cutting methods to tackle the most unsustainable areas mentioned above. For instance, in the area of transportation, a recent UN-Habitat report suggests that city managers must go beyond the building of transport infrastructure and look at the interconnectivity of different modes of transportation to fully address urban mobility challenges.8,9 Sustainable urban planning needs to take into consideration physical, legal and financial approaches to urban development that are coupled with environmental considerations.

The question is what we consider as fundamental to our well-being, and how we can steer urbanization away from its unsustainable path. The Greener Cities Partnership, a joint initiative between UN-Habitat and UN Environment, came into existence in 2014 to tackle exactly these questions, based on a vision to further develop ‘Greener Cities’ thinking and to re-shape the discussion around the importance of urban ecology, health and resilience.

The focus here is not just on finding new innovative tools that can be introduced to cities, but also to re-think the current urban metabolism, and to re-develop existing institutional structures, strategic frameworks and to retrofit existing urban infrastructure where possible. The initiative identified three basic ‘Greener Cities’ solutions as a starting point: The first is to drive up the economic engine, and particularly the focus on job creation and access to jobs.

The second is to mainstream environmental perspectives into local, national and global urban policy-making. The third point is to improve the environmental conscience of all stakeholders – if national or local governments do not empower their citizens to think sustainably, we will not have the desired transformational impact. This is also applicable vice versa.

The reasons why ‘Greener Cities’ are so relevant today are deeply rooted in the timely calling for integral solutions to the urban environment, public well-being and most importantly, the health of our planet and our citizens. Our vision is to generate knowledge, spread and develop innovative ideas and programs, and implement ‘Greener Cities’ thinking globally.

The Greener Cities Partnership, with its ambition to tackle urban environmental challenges through advocacy, knowledge exchange and practical actions, makes full use of its long-standing and pioneering expertise in the areas of urban planning, urban basic services as well as environmental policy-making, and strives to be the thought leader in the area of ‘Greener Cities’.

1. UN-Habitat (2016): World Cities Report 2016.

2. World Bank (2012): What a Waste: A Global Review of Solid Waste Management.

3. UN-Habitat (2011): “Hot Cities: battle-ground for climate change”. From: Cities and Climate Change: Global Report on Human Settlements 2011.

4. UN-Habitat (2013): Optimizing Infrastructure: Urban Patterns for a Green Economy.

5. UN-Habitat (2013): Clustering for Competitiveness: Urban Patterns for a Green Economy.

6. WHO (2016). Ambient air pollution: A global assessment of exposure and burden of disease.

7. UN-Habitat (2016): The New Urban Agenda.

8. UN-Habitat (2013): Optimizing Infrastructure: Urban Patterns for a Green Economy.

9. World Bank (2012): What a Waste: A Global Review of Solid Waste Management.