FORWARD

Are cities moving to the seaside? The coast has always been conducive to the development of cities, but this trend has gathered pace in recent decades, and shows no sign of slowing down.

In 2009, 67% of conurbations of more than 10 million inhabitants worldwide were located on the coast, and these mega-cities are expected to reach 80 million inhabitants by 2030. All over the planet, the growth of coastal urban zones is outstripping that of other cities.

Rising sea levels, monsoons and hurricanes

Coastal cities are becoming increasingly dense, populated and powerful, and increasingly fragile too. From New York to Manilla, Lagos and Copenhagen, seaside cities of all sizes are amongst the habitats that are most exposed to the consequences of global warming, precisely because they are close to the oceans. Flooding and rising water levels alone could cost almost $1,000 billion per year in 2050, if no measures are taken, according to a recent report by the World Bank.

Global warming will increase the frequency of other events in other parts of the world, such as monsoons, cyclones and hurricanes. These events present all the major functions of coastal cities with huge challenges: housing, public spaces, energy, transport, health and drinking water systems, etc. The lowest urban zones will be faced with the rise in the level of the water, which could engulf entire districts. Cities in China (Shanghai),

India (Calcutta) and South-East Asia (Jakarta) are under the greatest threat, but forecasts of the rise in the sea level have shown that, if greenhouse gas emissions continue at the current rate, New York, Tokyo, Miami, London and Rotterdam could also be impacted in a century or two, according to a study by the Climate Central think tank.

Flee seaside cities, or reinvent them?

Leaving the coast to move inland is an increasingly common idea, exposed in the reports of the GIEC, in the columns of the New York Times or even by engineering consultancies. But on the other hand, new utopians suggest to take the head by building offshore cities, as shown by the projects for floating cities of the Seasteading Institute in the United States, or Aequorea, the futuristic concept devised by the Belgian architect Vincent Callebaut: a huge nautical and subaquatic structure printed in 3D from algae and plastic waste from the ocean gyres.

Usbek & Rica is a French publication available in digital, print and event-based formats. Its mission is to explore the near, distant and very long-term future , enthusiastically and optimistically. open_resource magazine invited it to indulge in this forward-looking exercise.

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