Towards a green economy 1 Introduction

This chapter makes a case for greening cities. It describes the environmental, social and economic consequences of greening urban systems and infrastructure and provides guidance to policy makers on how to make cities more environmentally friendly.

An introduction to the concept of green cities is followed by Section 2, which presents related challenges and opportunities. Section 3 analyses the economic, social, and environmental benefits of city greening, while Section 4 summarises green practices across a number of urban sectors. Section 5 offers advice on enabling conditions for green cities. Section 6 concludes the chapter.

1.1 Cities

A city is a social, ecological, and economic system within a defined geographic territory. It is characterised by a particular human settlement pattern that associates with its functional or administrative region, a critical mass and density of people, man-made structures and activities (OECD and China Development Research Foundation 2010). Most commonly, cities are differentiated from other settlements by their population size and functional complexity (Fellmann et al. 1996). The definition of cities varies significantly from nation to nation, and is not always dependent on population size but can also reflect administrative or historical status (Satterthwaite 2008). The definition of urban areas tends to rely more on a population minimum but varies dramatically since it is dependent on unit size designations given by individual governments, which can range from minimum thresholds of 200 to 20,000 inhabitants upwards (UN Statistics Division 2008).1

1.2 Green cities

Green cities are defined as those that are environmentally

friendly.2 Indicators measuring

environmental performance can include: levels of pollution and carbon emission, energy and water consumption, water quality, energy mix, waste volumes and recycling rates, green-space ratios, primary forests, and agricultural land loss (Meadows 1999; Brugmann 1999). Other indicators include the share of apartment living, motorisation rate, and modal share of urban

transport. Another important measure of humanity’s demand on nature is the Ecological Footprint (Ewing et al. 2010).3

Defining green cities by their environmental

performance does not mean social equity issues are ignored. In fact, and as detailed below, greener living environments can play an important role in making cities more equitable for their residents.

There are also existing cities that are referred to as green because of their ambitious green policies, a range of green projects and a principal trajectory towards a better environmental performance. A number of cities in western Europe, the USA and Canada have pioneered green strategies.4

Freiburg, a city of 200,000 inhabitants

in Germany, has a long tradition of sustainable building and investment in recycling and it reduced CO2

emissions per capita by 12 per cent between 1992

and 2003 (Duennhoff and Hertle 2005). Several cities in developing countries, especially in South America, have also branded themselves green. Authorities in Curitiba, Brazil introduced policies to integrate land- use and transport planning and by the 1970s the city was equipped with an innovative bus rapid transit system (Economist Intelligence Unit 2010). Singapore introduced the world’s first road-charging scheme in the 1980s and it is now at the forefront of sustainable policies on waste, water and the greening of the environment (Phang 1993; Suzuki et al. 2010).

1. Satterthwaite (2008) estimates that a quarter of the world’s population lives in cities below 500,000 and another quarter in urban areas below 500,000 inhabitants. He suggests that roughly two-thirds of the world’s population live in rural areas and small towns. This indirectly suggests that about one-third of the global population might live in cities.

2. The greening of cities requires some, or preferably all, of the following: (1) controlling diseases and their health burden; (2) reducing chemical and physical hazards; (3) developing high quality urban environments for all; (4) minimising transfers of environmental costs to areas outside the city; and (5) ensuring progress towards sustainable consumption (Satterthwaite 1997). This chapter cuts across all five areas, but the issue of cities in relation to climate change – given its primacy in international environmental policy – is given added weight.

3. Ecological footprint measures how much biologically productive land and water area a human population or activity requires to produce the resource it consumes and to absorb its wastes, using prevailing technology and resource management practices. These areas are scaled according to their biological productivity to provide a comparable unit, the so-called global hectare.

4. While many of these initiatives have made major strides in reducing carbon emissions, it is important to note that none of these cities possesses an ecological footprint below 4 hectares per capita (UN-HABITAT 2008; own calculation by Arup) – more than twice the world average biocapacity per capita in 2006 – suggesting that there is still some way to go in implementing sustainable change.

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