Humanity on the Move: Unlocking the Transformative Power of Cities
Within the next few decades, more than 2–3 billion people worldwide will move from the country to the cities, implying impacts on living conditions, poverty and climate. Against this background, the population of the world’s slums will be doubled, and - as cities are responsible for a disproportionately high percentage of greenhouse gas emissions - the energy-intensive production of buildings with cement and steel will result in such huge amounts of greenhouse gases by 2050 that the world’s emissions budget of the 1,5 °C target - as recently adopted in the Paris Agreement - would be already exhausted. At the same time, cities are notably affected by global warming. Urban development, therefore, should focus more on the surrounding regions rather than on expanding densification. To initiate this fundamental change of perspective towards more sustainable urbanization, conditions for sustainable, urban societies must be created at the global scope, e.g. at the level of the G20, where Germany could play a key role during its Presidency in 2017; through a reformation and strengthening of the United Nations Settlement Programme (UN-Habitat); regular scientific progress reports; or even the creation of a committee similar to the Intergovernmental Panel on Climate Change (IPCC) being responsible for an assessment of the scientific status quo on global urbanization. Thus the WBGU’s core recommendations include advices regarding climate and resources (such as the replacement of all fossil sources of CO2 emissions in cities with alternatives by 2070 and the reduction of energy consumption, or the establishment of a circular economy in cities), people-oriented cities (such as the reduction of inequalities between the rich and the poor, a cross-sectoral perspective on urban health, and land use in compatibility with the common goods), international politics (e.g. strengthening urban societies as political players in international negotiations, and orienting international development finance more towards cities and sustainability criteria), and finally research (such as the establishment of a Max Planck Institute for Urban Transformation). A change of perspective towards more sustainable urban societies therefore is a fundamental need, since this urbanization surge will be the key driver of global change in the 21st century.