replenish

The Thwaites Glacier is an enormous Antarctic Glacier. Its area is larger than that of Florida – in fact, larger than 30 other U.S. states – and it is melting. It has been retreating for 80 years but has accelerated its pace in the past 30. Its shedding of ice into the ocean already contributes 4% of global sea level rise. If it collapsed entirely, it would raise sea levels by more than 2 feet. For this reason, it has been dubbed the Doomsday Glacier.

A team of scientists has been studying it since 2018 in order to better understand what is happening within the glacier. They sent a torpedo-shaped robot to the glacier’s grounding line, which is the point at which the ice rises up from the seabed and starts to float. The underside of Thwaites is insulated by a thin layer of cold water. However, at the grounding line, tidal action is pumping warmer sea water at high pressure as far as six miles under the ice. This is disrupting the insulating layer and is speeding up the retreat of the glacier.

The potential collapse of the glacier is not even the only massive risk it poses. It also acts like a cork, holding back the vast Antarctic ice sheet. If that ice sheet were ever to collapse, sea levels could rise 10 feet.

A critical unanswered question is whether the ultimate collapse of Thwaites Glacier is already irreversible. There are regular heavy snowfalls that occur in the Antarctic which help replenish ice loss. Whether nations’ progress in slowing climate change can change the balance between ice accumulation and ice loss on the glacier remains to be seen.

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‘Doomsday’ glacier set to melt faster and swell seas as world heats up, say scientists

Photo, posted January 3, 2022, courtesy of Felton Davis via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

Biocrusts are complex ecosystems that form a thin layer on the surface of soils in arid and semiarid environments. They are composed of variety of microbes including cyanobacteria, green algae, fungi, lichens, and mosses. Biocrusts play a crucial role in maintaining soil health and ecosystem sustainability.

Biocrusts are under assault from human activities including agriculture, urbanization, and off-road vehicle use. Climate change is also placing stress on biocrusts, which are struggling to adapt to increasing temperatures.

Researchers at Arizona State University have proposed a novel approach to restoring healthy biocrusts. Their idea is to make use of solar energy farms as nurseries for generating fresh biocrust. The arrays of solar panels serve as shields from excessive heat and allow biocrusts to flourish and develop. The newly generated biocrusts can then be used to replenish arid lands where the existing biocrusts have been damaged or destroyed.

When such biocrusts are harvested, the natural recovery process is rather slow, taking around six or eight years to fully recuperate. But the researchers found that when harvested areas are reinoculated with the microbes, the biocrust cover can reach near-original levels within a year.

The ASU researchers demonstrated the viability of the approach in a three-year study at a solar farm in Arizona’s lower Sonoran Desert. Based on their results, they conclude that the use of large solar farms for this purpose could provide a low-cost, low-impact, and high-capacity method to regenerate biocrusts and enable soil restoration on a regional scale. They have dubbed their new approach as “crustivoltaics.”

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Using solar farms to generate fresh desert soil crust

Photo, posted March 12, 2023, courtesy of Eric Peterson via Flickr.

Earth Wise is a production of WAMC Northeast Public Radio

The doomsday glacier

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Restoring Biocrusts | Earth Wise

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