Home Science Greenland’s Melting Glaciers Spew a Sophisticated Treasure: Sand

Greenland’s Melting Glaciers Spew a Sophisticated Treasure: Sand

Greenland’s Melting Glaciers Spew a Sophisticated Treasure: Sand


That sediment is particular, certainly. Desert sand from, say, the Sahara is not any good for making concrete as a result of it’s too rounded and uniform. Over millennia, winds push these grains round, sprucing them. If you happen to make concrete out of such sand, “it is nearly like constructing with marbles,” says Bendixen. “You need particles which can be extra angular in form, not rounded. And that sort of fabric is precisely what you get from rivers, for instance, or materials that has been deposited by glaciers.”

As Greenland’s ice sheet—which covers 700,000 sq. miles and is as much as 10,000 ft thick—rubs towards the land, it grinds up sediment, together with sand, superb silt, and bigger chunks of gravel. And because the ice melts, torrents of water carry all that particles to the ocean, whereas the pounding of the rivers themselves additional erodes the panorama. In comparison with the hundreds of years that sand spends rolling across the Sahara and changing into rounded, the particles coming off Greenland are more energizing. They’re extra angular and extra diversely formed. As a substitute of performing like marbles, they match collectively like items of a jigsaw puzzle, which is sweet for concrete.

{Photograph}: Nicolaj Krog Larsen

Greenland already harvests its sand for native, small-scale concrete manufacturing, since importing sand can be prohibitively costly. That is restricted to home corporations, who need to win non-exclusive permits after passing environmental overview by the federal government’s scientific advisers. They will additionally apply to export the sand, however that requires extra licensing. “We’re principally additionally open for sand extraction aiming at export, however then will probably be handled like every other mining exercise,” says Kim Zinck-Jørgensen, of the Greenland authorities’s Mineral Licence and Security Authority. “And for that you will have a a lot larger setup with rules and in addition environmental influence assessments, social influence assessments.” 

At present, dredging boats suck up sediment alongside the coast and filter out the sand, which is then introduced again onshore. But when Greenland decides to scale up sand extraction for export, that may imply massive ships must haul the stuff away to worldwide ports. “It is vital to emphasize that for those who extract no matter pure useful resource, there will probably be environmental penalties,” says Bendixen. “However actually, right here the environmental penalties might be tremendous broad.”

For one, these massive ships may also be bringing in ballast, or the water they’ve collected from elsewhere and saved of their hulls for steadiness. If that ballast is launched off the coast of Greenland, it could introduce invasive species. And, in fact, dredging coastal sediments would additional endanger underwater native creatures—and on land, elevated mining operations may scare away the sport that Inuit hunters depend on. (Greenland’s inhabitants is about 90 % indigenous Inuit. The Greenland department of the Inuit Circumpolar Council, an NGO representing Inuit peoples, declined to remark for this story.) 



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