He wants to build a wall to save humanity from the “glacier of the Apocalypse”

As the oceans warm, ocean currents erode glaciers, such as Thwaites in Antarctica, bringing them closer to a collapsecollapse total, with dramatic global consequences.

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Thwaites, the glacier with apocalyptic potential

Thwaites, dubbed the “apocalypse glacier” in 2017 by writer Jeff Goodell, is a gigantic glacier located in the western part of Antarctica. Its dimensions: 600 kilometers long, 120 kilometers wide and 1 kilometer thick, the size of a country like Ireland. Let us then imagine that Ireland disappears and completely dissolves into the global ocean. Because this is what awaits this glacier: due to global warming caused by transmissionstransmissions of greenhouse gases of human origin, the flow of warm, salty seawater towards the depths of the ocean is accentuated, colliding with the thick ice walls that until now prevented the collapse of the edge of the platform, melting them little by little.

In addition, the Thwaites has structural weaknesses: in 2019 a huge cavity was discovered under the glacier that weakened the building. A study also identified cracks causing visible cracks in the glacier, and between 50 and 70% of them could fracture in the coming years if they fill with water.

Its melting has already contributed to 4% of global sea level rise

The fact is that the meltingmelting The destruction of this gigantic glacier began long ago and is accelerating at an alarming rate: since 2000, Thwaites has lost more than a trillion tons of ice, or 30% more than the amount of freshwater previously rejected. According to glaciologists, the melting of the floating zone of the glacier would become effective within 5 years and would lead to its total disappearance in the coming centuries.

Its collapse alone would cause a rise in sea level of 50 centimeters, and with it the displacement of 97 million humans. Except that the melting of this giant will have an unprecedented domino effect: currently, this gigantic Antarctic ice shelf prevents warm sea waters from reaching other glaciers. Therefore, the collapse of the Thwaites Glacier would trigger a melting cascade that could raise sea levels by another 3 meters, hence its name as the glacier of the apocalypse. As a reminder, 40% of humanity lives within 100 kilometers of the coast and, by 2050, the world is expected to have 140 million climate refugees. But rising sea levels are far from the only consequence of this collapse.

Specifically, what will be the consequences?

A considerable supply of warm, fresh water will modify ocean currents: the thermohaline circulationthermohaline circulation based on temperature and salinitysalinity from massesmasses water that forms the world ocean. As an indication, Antarctica has gained +3°C in 50 years, a disturbance that will ultimately not allow adequate transport of the nutrientsnutrients Necessary for aquatic living beings.

Those who live mainly in the icebergiceberg will not be left out: apart from the polar bearspolar bearsMelting ice could reduce the number of colonies of emperor penguinsemperor penguins by 93% at the end of the century. And these inflows of fresh water are also not good news for the reserves that humanity risks running out of water, because the melting of ice affects the quality of fresh water on the surface and underground, which is even more worrying. when we know that the world reserves are estimated at 2.8%, of which only 0.7% is drinkable.

Finally, the ultimate consequence will be the acceleration of the phenomenon responsible for this entire cascade of effects: the famous global warming. On the one hand, ice helps regulate the climate, through its colorcolor white that reflects 95% of the solar radiationsolar radiation : Therefore, a reduction in this white surface is not good news for the greenhouse effect. On the other hand, melting ice releases CO2 imprisoned for many years, and thus accelerates global warming: IPCCIPCC plans to release several hundred gigatonnes by 2100. If you are not convinced by this paragraph of the climate emergency in question…

Building an iron wall for social justice: really?

John Moore, a glaciologist and geoengineering researcher at the University of Lapland, wants to install giant curtains submarinessubmarines 100 kilometers in length to prevent warm sea water from reaching and, therefore, melting the glaciers. In theory, these facilities would block the flow of warm currents into the Thwaites to stop melting and give the ice shelf time to rebuild.

Researchers at the University of Cambridge are currently testing a meter-long prototype inside tanks. Once the functionality of the system has been demonstrated, the tests will be carried out in the river chamberand if all goes well, they could test a set of 10 meter long curtain prototypes in a fjordfjord Norwegian by 2025.

In short, a first curtaincurtain It would block a narrow underwater bottleneck (5 kilometers) that represents the main route of warm water entry to the western Thwaites Glacier, the most vulnerable part of the glacier. Later curtains would traverse wider and deeper swaths of the seafloor, and cost-benefit analyzes of the curtains peaked at target blocking depths of between 500 and 550 metres… Despite these academic analyses, the project it would still cost 50 billion dollars.

However, a key argument is put forward: social justice. According to John Moore, this is a much fairer way to address sea level rise than simply saying: ” we should dedicate this moneymoney to adaptation “. An important argument in the face of the very unequal budget of cities to protect against rising water levels. And it would be the first. WallWall of History that does not divide people.

In the face of an emergency you have to act… But not in any way

As you can imagine, this project is controversial. Advocates of glacier geoengineering research, like John Moore, say it’s time to intervene. Other experts disagree and believe that reducing carbon emissions is the only viable way to slow the melting of glaciers.

In your opinion: is this another techno-solutionist demonstration in the face of the inevitable melting of the ice? Wouldn’t it be better to focus on reducing greenhouse gas emissions, rather than relying on technology? Does the climate emergency allow us to act on the causes of warming or only fight against its consequences? And what about those who will finance this titanic wall?

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