Greenland’s melting glaciers are spewing out an intricate treasure: sand

This sediment is indeed something special. Desert sand from the Sahara, for example, is not suitable for concrete production because it is too round and even. For millennia, winds push these grains around and polish them. Making concrete out of sand like that “is almost like building with marbles,” says Bendixen. “You want particles that have a more angular shape, not round. And that’s exactly the kind of material you get from rivers, for example, or material deposited by glaciers.”

As Greenland’s ice sheet — which covers 700,000 square miles and is up to 10,000 feet thick — rubs against land, it grinds up sediments including sand, fine silt and larger chunks of gravel. And as the ice melts, torrents of water carry all that debris into the sea, while the pounding of the rivers themselves continue to erode the landscape. Compared to the thousands of years sand has been rolling and rounding through the Sahara Desert, the particles coming from Greenland are fresher. They are more angular and shaped in a variety of ways. Rather than acting like marbles, they fit together like pieces of a jigsaw puzzle, which is good for concrete.

Photo: Nicolaj Krog Larsen

Greenland is already harvesting its sand for local small-scale concrete production, as importing sand would be prohibitively expensive. This is limited to domestic companies, which must obtain non-exclusive permits after passing the environmental assessment by the government’s scientific advisors. You can also apply to export the sand, but that requires an additional license. “We are also fundamentally open to sand extraction for export, but then it will be treated like any other mining activity,” says Kim Zinck-Jørgensen of Greenland’s government agency for mineral licenses and security. “And for that you have a much larger set of regulations and also environmental impact assessments, social impact assessments.”

Currently, dredging boats suck up sediment along the coast and filter out the sand, which is then brought back to shore. But if Greenland decides to expand sand extraction for export, that would mean large ships would have to transport the material to international ports. “It’s important to emphasize that the extraction of any natural resource will have environmental consequences,” says Bendixen. “But really, the environmental consequences here can be very far-reaching.”

For one, these large ships will also bring in ballast, or the water they have collected elsewhere and stored in their hulls to compensate. If this ballast is released off the coast of Greenland, invasive species can be introduced. And of course, dredging coastal sediments would further endanger native underwater creatures — and on land, increased mining operations could scare off the game that Inuit hunters rely on. (About 90 percent of Greenland’s population is indigenous Inuit. The Greenland branch of the Inuit Circumpolar Council, an NGO representing Inuit peoples, declined to comment on this story.)

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