Greenland could start to export sand in a rare positive spinoff from global warming that is melting the island’s vast ice sheet and washing large amounts of sediment into the sea.

Mining of sand and gravel, widely used in the construction industry, could boost the economy for Greenland’s 56,000 population who have wide powers of self-rule within Denmark but rely heavily on subsidies from Copenhagen.

By mining sand, “Greenland could benefit from the challenges brought by climate change,” a team of scientists in Denmark and the United States wrote in the journal Nature Sustainability.

The study, headlined “Promises and perils of sand exploitation in Greenland,” said the Arctic island would have to assess risks of coastal mining, especially to fisheries.

Rising global temperatures are melting the Greenland ice sheet, which locks up enough water to raise global sea levels by about seven meters if it ever all thawed, and carrying ever more sand and gravel into coastal fjords.

“You can think of it (the melting ice) as a tap that pours out sediment to the coast,” said lead author Mette Bendixen, a researcher at the University of Colorado’s Institute of Arctic and Alpine Research.

Worldwide demand for sand totaled about 9.55 billion tons in 2017 with a market value of US$99.5 billion and is projected to reach almost US$481 billion in 2100, driven by rising demand and likely shortages, the study said.

David Boertmann of Aarhus University, who was not involved in the study, said there was already some local mining of sand for the domestic construction industry in Greenland.

Drawbacks for Greenland, common to other mining projects on the island ranging from uranium to rare earth minerals, include the distance to markets in Europe and North America, he said.

Still, Bendixen said sand was already often transported long distances, such as to Los Angeles from Vancouver or from Australia to Dubai.

The study said that sand and gravel might also be used in the future to reinforce beaches and coastlines at risk of rising sea levels, caused in part by Greenland’s thaw.

Words to Learn 相关词汇

【副产品】fùchǎnpǐn spinoff a collateral or derived product or effect, by-product

【融化】rónghuà thaw go from a frozen to a liquid state

全球变暖正在融化格陵兰岛的巨大冰盖，并将大量沉积物冲入海里。由此带来的一个罕见的积极效应就是，格陵兰岛可以开始出口沙子了。

沙子和碎石广泛用于建筑行业，其开采可以促进格陵兰岛的经济发展，这里居住着5.6万人口，他们在丹麦拥有广泛的自治权，但严重依赖哥本哈根的补贴。

丹麦和美国的一个科学家团队在《自然·可持续发展》杂志上写道，通过开采沙子，“格陵兰岛可以从气候变化带来的挑战中获益”。

这篇题为《格陵兰岛开采沙子的希望与风险》的研究报告称，格陵兰岛需要评估沿海开采沙子的风险，尤其是对渔业的风险。

不断上升的全球气温正在融化格陵兰岛的冰盖，并将越来越多的沙子和碎石带入沿海峡湾。格陵兰岛冰盖锁住了大量的水，如果全部融化，全球海平面将上升大约7米。

该研究的第一作者、科罗拉多大学北极与阿尔卑斯山研究所的研究员梅特· 本迪克森说：“你可以将它（融化的冰）想象成向海岸倾泻沉积物的阀门。”

这份研究报告称，2017年全球对沙子的需求总共达到约95.5亿吨，市场价值995亿美元

（约合6661亿元人民币），由于需求上升以及供应量可能不足，预计到2100年，市场价值将达到近4810亿美元。

并未参与这项研究的奥胡斯大学的戴维· 伯尔特曼说，当地已经开始开采沙子用于格陵兰境内的建筑业。

他说，与铀和稀土等矿业开采项目一样，格陵兰岛开采沙子的面临的不利条件包括与欧洲及北美市场之间的距离。

不过，本迪克森说，沙子已经在长途运输，比如从温哥华到洛杉矶，或从澳大利亚到迪拜。

这份研究报告称，沙子和碎石未来或许还会被用于加固面临海平面上涨风险的海滩和海岸线，而这些在某种程度上也是由于格陵兰岛地区的冰盖融化导致的。

(Chinadaily.com.cn)