About 4,2 billion of us—more than half of humanity—live in cities today. By 2030, which is barely 11 years from now, this figure is expected to reach 5 billion. This rapid urbanisation is exerting a huge pressure on fresh water supplies, sewage, the living environment, and public health, among other things. One of the key figures around cities today is that while the world’s cities occupy just 3 % of the Earth’s land, they account for 60-80 % of energy consumption and 75 % of carbon emissions.
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[Says Ringelstein,] "I believe, and many of my colleagues are with me on this, that cities are the places where the greatest forces of change are currently in operation. And I think if we can solve issues at the city scale we’re actually going to have our biggest bang for our buck in terms of planetary health."
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