Currently, there is a unique opportunity for the global scientific community to significantly contribute to sustainable futures through the UN’s Sustainable Development Goal (SDG) process. A critical issue now under debate in the UN Open Working Group (OWG) on the SDGs is how they should deal with urban issues.1 At stake is whether there should be a stand-alone urban goal (and what it might be), and a choice between the alternatives of dedicated sub-national reporting or a continuation of the situation that prevailed under the Millennium Development Goals (MDGs) that are set to expire in 2015.
Decision making within the UN system is confined to 193 member states. While many of these are sympathetic to ensuring that urban questions are squarely addressed, some are clearly threatened by the implication that development assistance may increasingly shift to cities and away from rural areas in less developed and primarily rural economies. For others, who may prioritize urban issues, including infrastructure development, urban health and well being, biodiversity, or disaster risk, it is not clear whether a stand-alone goal or a mainstreamed approach in which these factors are incorporated in all the other goals will more effectively lead to appropriate action in urban areas.2
The Global Urban Transition
Given the profoundly transformative impact of urbanization (in terms of rural-urban migration, the growing proportion of people living in cities, and the increasing importance of urban centers for global economic and resource flows) there has rarely been a moment when getting the urban development agenda right has been of such crucial importance. Well-planned and governed, cities can enable high standards of living and economic development without unsustainable environmental resource use; they can protect local and regional ecosystems, maintain low pollution levels, and improve human health and wellbeing.3 This is especially true for much of Africa and Asia, which are the poorest, least urbanized, but most rapidly urbanizing regions in the world today.
The unprecedented pace and scale of urban growth, the cascading impacts that urban forms have on human wellbeing and resource use everywhere, and the risk that the current massive physical, technical, and institutional investments in urban areas will “lock in” features detrimental to health and sustainability make urbanization a critical driver of global change. Today, half the world’s seven billion people live in cities. By 2030 there will be over one billion more urban residents and, for the first time ever, in many parts of the world the number of rural residents will start to shrink. The anticipated increase in urban population of 2.7 billion people from 2010 to 2050 is larger than the entire world population in 1950—this translates into the addition of over 1 million people to the world’s cities every week (fig.1). By 2050, the urban share will have grown to two-thirds of the world’s population. Already, roughly three-quarters of global economic activity is urban, and as the urban population grows, so will the fraction of global GDP and investments in cities.
Addressing Urbanization in the Sustainable Development Goals
The moment of the adoption of the Sustainable Development Goals, or SDGs, in 2015 could represent a turning point in how cities are perceived, structured, and managed. Inevitably, the precise formulation of the UN SDGs—including the choice of targets and indicators—will impact development priorities in and across urban and rural places. A possible urban SDG is important beyond city boundaries and over generations: the infrastructure of the built urban environment draws from regional ecosystems and has a lifecycle measured in decades. Whatever we build now will determine the path for future generations over large geographical scales.
One important function of a stand-alone urban SDG would be to declare to the world that we have crossed an important global threshold and are now a predominantly urban species—and will continue to become more so. This could signal to heads of state the need for a national urban agenda and enable citizens and policymakers to reimagine urban sustainable development pathways and to rally urban stakeholders around practical evidence-based problem solving—clearly, ‘cities-as-usual’ will not suffice. It would also help mobilize efforts to: 1) address the challenges of urban poverty and access to basic services that billions of slum dwellers across the world struggle with each day; 2) promote integrated infrastructure design and service delivery as well as improved land use planning and efficient spatial concentration; and 3) contribute to urban resilience in the face of climate change and other disaster risks—benefits that disparate goals or targets may make difficult to realize for cities.
Conversely, mainstreaming urban questions within other SDGs, through defining urban targets and indicators, could send a powerful message that urbanization and urban phenomena touch on all aspects of sustainable development. In the context of a framework that is necessarily simplified to allow for political feasibility, mainstreamed urban targets and indicators in other SDGs would affirm the kinds of approaches that are critical to solving complex urban problems—approaches that consider the systems within which these problems are embedded and with appropriate sub-national data, address them in an integrated way.
In an important sense, however, the question of stand-alone versus mainstreaming, while politically significant in signaling the precedence of cities within the sustainable development framework, is less important than the setting of targets, selection of indicators, and determination of scales and modes of reporting. It is precisely these targets and indicators that will set the tone for development priorities. With this in mind, it is essential that they be well-defined, methodologically sound, and feasible for all nation-states to collect at sub-national scales. Wherever possible, they should be multi-dimensional, capturing aspects of sustainability and development in multiple domains or sectors and illuminating the connections among them. Indicators need not be complex to fulfill such criteria; for example, a measure of the proportion of urban trips made using active transport modes (i.e., walking, cycling, and public transportation) would capture information relevant and important for issues related to health, transport, energy, environmental pollution, and land use. There is a growing body of evidence from which such metrics can be drawn, and since it is likely that the SDGs will be the single most comprehensive data collection system of the early 21st century, their structure may enable or suppress analytical possibilities across all of science.
A Role for Science and Scientists
The SDG process must be much more than just a refinement of the MDGs. It should aim, rather, at a fundamental expansion of the development agenda to include evolving environmental, social, and economic questions that impact the lives of all people, everywhere. To ensure that future urban realities are represented in the post-2015 development agenda, it will be critical that scientists engage in the setting of appropriate targets and indicators, prioritizing monitoring at subnational scales. The SDGs need, among other things, to be:
- flexible—to enable cross-referencing of environmental, social, and economic questions;
- scalable—adopting indicators that make sense locally but, where appropriate, can be adapted for national, regional or global agendas; and,
- based on credible data, including the expansion of sub-national data where necessary.
Addressing the existing gaps in data, theory, and analytical capacity—especially at the urban scale—should be a priority for the global scientific community. The Future Earth program provides an opportunity to mobilize a large community of scientists to address the challenges of sustainable development and the reporting systems against which progress on the SDG goals will be measured.4 Scientists with urban and data expertise must be called on to join the technical discussions on selecting the SDG targets and indicators. If poorly defined and managed, these will almost certainly have unintended consequences and negative outcomes that will be difficult to reverse. Given the critical importance of rapid current and future urbanization for the national and global sustainable development, silence from the scientific community may be the most dangerous path of all.