A CRISIS OF PERCEPTION
For centuries, cities evolved gradually in terms of their physical and population size. This trend, however, dramatically shifted in the last 50 years, with urban growth occurring at an exponential scale and rate as urban population numbers spiked. By 2050, two-thirds of the world’s projected 9.7 billion population will live in urban areas, adding an estimated 2 billion people to cities mostly concentrated in Africa and Asia . This astounding rate of urban growth is equivalent to building a city with the population of London every seven weeks .
The situation is further aggravated by the vast suburbs and hinterlands of cities as they expand, with urban land growth far outpacing urban population growth. If the current trajectory of unsustainable urban sprawl were to continue, humanity will potentially urbanise another 1.2 million square kilometres of land by 2050 , equivalent to the size of South Africa. This in turn drives habitat losses and threatens biodiversity.
Aeria view of WOHA’s proposal for a Self-Sufficient City for Jakarta (Image courtesy of WOHA)
Extinction is already happening at about 1,000 times the historical rate , and as of year 2000, 88 per cent of global primary vegetation land cover have been destroyed in biodiversity hotspots . By 2030, urban growth could further destroy natural habitats that currently store carbon equivalent to emissions from 931 million cars on the road in one year . Up to 40 per cent of the species in some of the most biologically diverse areas around the world could also be lost .
Cities drive the global economy and global environmental change. It is therefore largely in the urban environment where the pressure, and opportunity, for change lies. Despite occupying only 3 per cent of the world’s land, cities today consume 75 per cent of all natural resources, produce 50 per cent of all waste, and account for 60 to 80 per cent of global greenhouse gas emissions . The materials used by the global economy have also more than tripled over the last 50 years and now exceeds 100 billion tonnes every year.
About 91.4 per cent of this continues to be extracted from Earth’s finite resources, with only 8.6 per cent of our global economy being circular in 2017 . Majority (52.2 per cent) of the materials entering the global economy every year are used by society as short-lived products, which then become waste. Such rapid and unsustainable urbanisation along with unrelenting material consumption and irresponsible lifestyle patterns over recent decades have resulted in the irreversible exploitation of natural resources, severe biodiversity and habitat losses, unmanaged generation of waste, significant environmental degradation, and unprecedented climate change.
This makes the world more vulnerable than ever to extreme natural events/disasters and rising sea levels as a result of global warming that poses a major and imminent threat, especially to the highly populated low-lying coastal regions of the world, including island nations like Singapore.
1 United Nations, Department of Economic and Social Affairs, Population Division (2019). World Population Prospects 2019: Highlights (ST/ESA/SER.A/423)
2 Nature in the Urban Century: A Global Assessment of Where and How to Conserve Nature for Biodiversity and Human Wellbeing (2018) Stockholm Resilience Centre, The Nature Conservancy
3 Angel S et al. (2011) Progress in Planning 75(2): 53-108 The Dimensions of Global Urban Expansion: Estimates and Projections for All Countries, 2000-2050
4 Pimm, S.L., et al., The Biodiversity of Species and Their Rates of Extinction, Distribution, and Protection. Science, 2014. 344(6187): p. 1246752
5 Seto K.C., et al., (2012) Global Forecasts of Urban Expansion to 2030 and Direct Impacts on Biodiversity and Carbon Pools
6 United Nations Economic and Social Council (2017) Urbanisation and Sustainable Development in Asia and the Pacific: Linkages and Policy Implications
7 The Circularity Gap Report 2020 by Circle Economy
8 The Systems View of Life, A Unifying Vision by Fritjof Capra and Pier Luigi Luisi