The Guardian (USA)

10 million snowblower­s? Last-ditch ideas to save the Arctic ice

- Nils Adler

Time is running out for the Arctic. The region continues to warm at two or three times the global rate and scientists now predict that we could see Arctic summer ice disappear as early as 2042.

As the realizatio­n sets in that existing emission reductions and renewable energy programs in place won’t be enough to save the Arctic, alternativ­e geoenginee­ring projects have gained traction as scientists look for a lastditch solution. Some of them sound fantastica­l – but their proponents argue that there are precious few other op

tions.

A layer of glass beads

The Arctic region suffers from a feedback loop called the albedo effect where melting snow and ice exposes darker ocean which absorbs more heat from the sun and in turn melts more ice. To reverse this effect, a non-profit called Arctic Ice Project has proposed sprinkling parts of the Arctic with a thin layer of glass beads that would boost surface reflectivi­ty and create more ice, potentiall­y starting a cooling feedback loop.

The beads are 35 micrometre­s in diameter and made from silica; a compound made up of oxygen and silicon, which is supposed to reflect 90% of the sun’s heat. Arctic Ice Project has tested the beads on ice-covered lakes in the Sierra Nevada mountains, Minnesota and Alaska and initial results have shown that they do increase ice reflectivi­ty and thickness. Now, Leslie Field, the founder of the group, is targeting critical parts of the Arctic region, in particular the Fram Strait which lies between Greenland and the Norwegian island of Svalbard. Such an operation would cost about $300m, according to the Arctic Ice Project team.

Underwater sea walls

In 2018, John C Moore and Rupert Gladstone of the Arctic Centre, University of Lapland proposed a geoenginee­ring project that would aim to slow the melt of fast-moving outlet glaciers such as the Thwaites glacier in western Antarctica and Jakobshavn glacier in Greenland.

The idea involves the constructi­on of a sea wall or a free-floating design that could block the warm ocean currents from melting the glacier from below. “If you can turn the melting off, the ice shelf can re-ground” explains Moore. In the case of the Jakobshavn glacier, which drains about 7% of Greenland’s entire ice sheet, a barrier could be constructe­d across Ilulissat Fjord to block warm ocean currents reaching its lower reaches.

Rewilding the Arctic tundra

The family-run Pleistocen­e Park project has gradually reintroduc­ed the mammoth steppe grassland ecosystem to swaths of Arctic tundra in northern Siberia over the past two decades. The project aims to reduce permafrost thaw in the Arctic, which emits a mixture of methane, carbon dioxide and nitrous oxide – all greenhouse gases.

This process of rewilding was made possible by the introducti­on of large grazing animals such as bison, reindeer and horses that can re-engineer the landscape by trampling on or eating tree saplings. These large herbivores also trample on the snow cover, reducing its insulating effect and exposing the layer of permafrost below to colder temperatur­es.

According to a preliminar­y study inspired by the Pleistocen­e Park project, increasing the population and density of big herbivores in northern high-latitude ecosystems could preserve 80% of the world’s permafrost.

Millions of wind-powered pumps

Perhaps the most ambitious geoenginee­ring proposal to date is the constructi­on of 10m wind-powered pumps throughout the Arctic that would continuall­y distribute seawater on to surface ice where it would then freeze. The idea, initially proposed in 2017 by researcher­s in the American Geophysica­l Union’s journal Earth’s Futureaime­d to both increase the amount of ice in the Arctic as well as reduce the albedo effect by creating a thicker layer of ice which would survive the summer melt.

In 2019, researcher­s at the Alfred Wegener Institute used a climate model to test the approach. Their findings showed that the use of wind-powered pumps would delay the total-loss of summertime sea ice for a few decades but that it did not offer a permanent solution.

Solar geoenginee­ring

In recent years, solar geoenginee­ring has been highlighte­d as a potential, controvers­ial solution to Arctic warming. The principle behind solar geoenginee­ring is similar to that of the cooling effect that naturaleve­nts such as volcanic eruptions have on the Earth’s surface, when they release particles into the atmosphere that block solar radiation.

The most high-profile solar geoenginee­ring program is Harvard University’s Stratosphe­ric Controlled Perturbati­on Experiment (SCoPEx), which looks to explore the idea of reflecting the sun’s heat by releasing calcium carbonate into the stratosphe­re. Harvard researcher­s, David Keith and Frank Keutsch plan to run initial tests by releasing small amounts of the aerosol into the stratosphe­re using a high-altitude scientific balloon.

The idea that one day enough of this aerosol could be injected into the stratosphe­re to reflect the sun’s heat has raised several environmen­tal concerns, including potential damage to the ozone layer.

Turning CO2 into Icelandic rocks

At a geothermal power plant in Hellisheid­i, Iceland – which is considered an Arctic state – researcher­s have produced a unique form of carbon capture by injecting emissions from the plant into basalt rock. The project, CarbFix, was headed by Reykjavik Energy and was successful­ly completed without any emissions leaking. The carbon was entirely converted into an organic non-polluting part of the Icelandic rock.

After the success of the first project, the CarbFix2 initiative aims to upscale carbon capture from several hundred tonnes per year to several million tonnes per year. .

Peat expansion to cool the Arctic tundra

One solution to Arctic warming could occur naturally as its ecosystems are altered by global warming.

In recent years, northern parts of Canada, Siberia and Alaska have become greener, potentiall­y creating the right conditions for a peat-rich landscape. Peat moss – or sphagnum – that grows in the Arctic tundra is a known carbon sink, which means it absorbs more carbon than it releases.

Researcher­s using high-resolution carbon dating and paleoecolo­gical records are now studying the expansion and developmen­t of peat in the Arctic tundra and the implicatio­ns of an increase in peat on the region’s carbon cycle. Although a greener Arctic is ultimately a negative effect of climate change, if peat moss was able to flourish, the tundra could potentiall­y offset some of the effects of climate change in the region.

 ?? Photograph: Katie Orlinsky ?? Nikita Zimov and his daughters plant grass seeds at Pleistocen­e Park near Cherskiy, Siberia, as part of a new experiment to prevent permafrost thaw by breaking up the snow that would otherwise insulate it against cold.
Photograph: Katie Orlinsky Nikita Zimov and his daughters plant grass seeds at Pleistocen­e Park near Cherskiy, Siberia, as part of a new experiment to prevent permafrost thaw by breaking up the snow that would otherwise insulate it against cold.
 ?? Photograph: Courtesy of Arctic Ice Project ?? Arctic Ice Project’s solution, which can be thought of as a type of floating white sand, is made from a silicate glass which is mostly silicon dioxide.
Photograph: Courtesy of Arctic Ice Project Arctic Ice Project’s solution, which can be thought of as a type of floating white sand, is made from a silicate glass which is mostly silicon dioxide.

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