A microscopic look at why the world is running out of sand; Video
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The usefulness of sand depends on the science of each tiny little grain. We went on a sand scavenger hunt to collect some samples, look at them under a microscope, and try to figure out why sand scarcity is such a problem.
‘Art can play a valuable role’: climate change installations appear in New York
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The existential threat of climate change is being spelled out to New Yorkers via a selection of flashing highway signs that have been placed around the city.
New walls aim to hold back rising seas off Tanzania
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Coastal erosion and flooding threaten Dar es Salaam, one of Africa’s fastest-growing cities.