Greening the world economy through cities

Besides comprising a majority of the world's population, cities concentrate disproportional amounts of the world's economy and decision-making power. Further, though urban areas cover only around two percent of the Earth's surface, they consume 75 percent of its resources. Yet as a hub for social and political movements and centres of technological and institutional knowledge and innovation, cities can be a powerful catalyst of greener economies.

The growing size and importance of cities across the globe make them arguably the single most important entities in the fostering of a green economy. Because of their spatial distribution and diversity, the management of cities can be more responsive to urgent problems while being somewhat liberated from competing national interests (e.g., regional development agendas and sector lobbies) and responsibilities (such as national defense costs).

As a result, urban transitional activities are playing an increasingly important role in the implementation of policies regarding global environmental issues like climate change and biodiversity loss. The green economy provides another platform for ambitious cities to promote their green credentials.

Spatial organisation

The green economy will take on a different character in different cities depending on their level of development and spatial organisation. It is important to recognize that cities face different challenges. While urbanisation increases at a global scale, when this is differentiated by region the picture that emerges is unique to each individual city.

Cities in developed countries seek to grow by generating new jobs and industry. As a result, some cities are declining as they lose the battle for investment and talent.

African and Asian cities have some of the highest growth rates and their development path will have a crucial influence on global development in the 21 st century.

The way out of the urban development vs. environmental degradation dilemma is not necessarily to stop urban growth, but to harmonise the resulting opportunities and challenges.

Transitions

For those cities embarking on development transitions, it is important to remember that infrastructure lasts at least 30 years, but often much longer. Once in place, many management options become technical adaptation and retrofitting rather than new design. Therefore the need to understand the relative importance of different tools available to cities is crucial if the green economy is to become a precursor to sustainable development.

The way out of the urban development versus environmental degradation dilemma is not necessarily to stop urban growth, which is almost impossible in some cases, but to reconcile and harmonize the resulting opportunities and challenges.

History has proven that urbanisation can be managed in a way that promotes both the economy and human well-being. Because of the concentration of people, resources, knowledge and economic activities in urban areas, a properly managed cities-led green economy could provide the economy of scale, political momentum and efficiency gains necessary to lower the use of resources and energy.

Opportunities

The opportunities and the obstacles for a greener economy in cities are analysed by looking at the specific economic processes that take place in cities, namely transformation of space (urban development), production and consumption, circulation (trade and transportation) and the production of ecosystem services, social services and knowledge.

Understanding how to green those processes can have huge social, economic and environmental impacts on the cities and beyond.

Physical and spatial development of cities are among the most significant components of urban economy. Urban development transforms natural environment and resources into man-made superstructures and infrastructure and this transformation places significant stress on the remaining natural environment.

The way we build our cities also influences how we spend and distribute our economic resources. Urban forms and spatial distribution of urban functions play a critical role in this respect. Sprawled cities, where low-density is the norm and urban functions are distantly located, increase the consumption of energy and natural resources including both terrestrial and aquatic resources.

The cost of urban development is high in dispersed cities, as relatively large land areas are dedicated to urban infrastructure and utilities. For instance, 70 percent of the cost of urban water supply systems goes towards piping, and 30 percent of urban energy consumption goes towards the pumping of water and the collection of waste-water. Therefore a smaller land-use area can result in lower utility operation costs.

Infrastructure

Similar conclusions can also apply to transportation infrastructure. Compact cities with high density and mixed-use urban quarters (e.g.concentrating and combining retail, office and residential activities) can reduce travel activity and therefore result in energy-savings and lower levels of land-use change.

Overall, through the preservation of surrounding agricultural and forest land (for example, by combining agrarian activities and residential land use) cities can benefit from the ecosystem services provided by these areas, potentially reducing certain infrastructure costs while increasing the quality of life of its residents.

A key component of urban development that can promote the transition to a green economy is the superstructure: more specifically, the buildings. The building sector is one of the main contributors to carbon emissions, utilizing approximately 40 percent of global energy consumption; it consumes 12 percent of all fresh water and generates 40 percent of the total volume of waste. One of the key goals of the green urban economy is to promote energy and resource efficiency and to provide high quality, healthy and affordable buildings for urban residents.

In an increasingly urbanised world challenged by global environmental change and pervasive inequalities, cities are looking for new pathways to provide human well-being while using natural resources sustainably.

Developing a green economy for urban areas is a response to those challenges. Such an approach should take into account sustainable production and consumption issues, as cities consume vast amounts of resources to meet increasing demands for goods and services, which can lead to environmental impact and economic exploitation in the non-urban supply areas.

Sustainable consumption and production should aim to transform current environmental challenges faced by cities into economic opportunities by boosting the demand for more sustainable products and technologies, improving the environmental performance of products throughout their lifecycle, helping consumers to make informed choices, and by promoting awareness and lifestyle changes that help individuals to adapt their urban life to today's challenges.

- OurWorld2.0