Friday, June 24, 2016

Sand is the essential ingredient that makes modern life possible. And we are starting to run out.

Vince Beiser writes in the New York Times,
Sand is the essential ingredient that makes modern life possible. And we are starting to run out.

That’s mainly because the number and size of cities is exploding, especially in the developing world. Every year there are more people on the planet, and every year more of them move to cities. Since 1950, the world’s urban population has ballooned to over 3.9 billion from 746 million.

According to the United Nations Environment Program, in 2012 alone the world used enough concrete to build a wall 89 feet high and 89 feet wide around the Equator. From 2011 to 2013, China used more cement than the United States used in the entire 20th century.

To build those cities, people are pulling untold amounts of sand out of the ground. Usable sand is a finite resource. Desert sand, shaped more by wind than by water, generally doesn’t work for construction. To get the sand we need, we are stripping riverbeds, floodplains and beaches.

Extracting the stuff is an estimated $70 billion industry. It runs the gamut from multinational companies’ deploying enormous dredges to villagers toting shovels and buckets. In places where onshore sources have been exhausted, sand miners are turning to the seas.

This often inflicts terrible costs on the environment. In India, river sand mining is disrupting ecosystems, killing countless fish and birds. In Indonesia, some two dozen small islands are believed to have disappeared since 2005 because of sand mining. In Vietnam, miners have torn up hundreds of acres of forest to get at the sandy soil underneath.

Sand miners have damaged coral reefs in Kenya and undermined bridges in Liberia and Nigeria. Environmentalists tie sand dredging in San Francisco Bay to the erosion of nearby beaches.

...Sand is the thing modern cities are made of. Pretty much every apartment block, office tower and shopping mall from Beijing to Lagos, Nigeria, is made at least partly with concrete, which is basically just sand and gravel stuck together with cement. Every yard of asphalt road that connects all those buildings is also made with sand. So is every window in every one of those buildings.
Read more here.

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