Antarctica’s ice sheet is in danger of falling into the sea. Although it may restore stability to other continents, the destabilization is too extreme for any greenhouse gas reduction. Although the collapse of West Antarctic Ice Sheet could take many centuries, it will result in sea level rises of 3m worldwide. Two maps showing Antarctica are shown to the right. They show the West Antarctic Ice Sheet (image B), and the “after-simulated collapse” (image D). In the larger image to the left, the red area indicates where the snowstorm will occur. Credit: Levermann et al 2019. This would be a threat to highly-populated areas along the coast. This includes large cities like New York City and Calcutta. What kind of effort and how large would that human effort be to stop the West Antarctic Ice Sheet from falling into the ocean? ‘Absurd” project that could have severe environmental effects. Scientists at Germany’s Potsdam Institute for Climate Impact Research, (PIK), attempted to answer this question using computer simulations. The scientists conclude that pumping billions of tonnes of snow on the West Antarctic Ice Sheet would stabilize it enough to stop it from sliding into the ocean. Geoengineering would require unprecedented amounts of effort in order to achieve such a project in the most hostile environments on the planet. This would result in the destruction of a rare natural reserve and serious impacts on sensitive ecosystems. In a Science Advances paper, the researchers explain how they determined what size project such an undertaking would be. However, they aren’t proposing the project be stopped. They hope that by showing the absurdity of this feat they can help others understand the magnitude and danger of rising seas. Recent research has shown that West Antarctica’s glaciers are moving at a faster pace than thought. This is causing more sea level rise by releasing more ice into oceans. Some glaciers of the West Antarctic Ice Sheet, due to their nature, are instabile. The oceans below them are heating up, causing them melt. According to the authors, this effect “represents Antarctica’s strongest and fastest contribution to global ocean level rise.” Geoengineering is a huge feat. The latest findings show that strong cuts in greenhouse gas emissions will not stop the melting of the ice sheets. It would require several hundred billion tonnes of ocean water each year for several decades to make the necessary snowfall. Engineers would need to design equipment that heats, dehydrates, and raises the ocean water to make snow. The authors note that the ocean water must be elevated from sea level up to the top of ice sheets by 640m. The height of this tower is roughly the same as that of the 128-storey Shanghai Tower which, at 632m, is the second-tallest building in the entire world. The area that huge snow cannons will need to cover is approximately 52,000 square kilometers. This would be roughly the same size as Costa Rica, or half of Iceland. The project would need at least 12,000 wind turbines to power the snowmaking equipment. The authors note that “the practical realization of elevating or distributing ocean water would require an extraordinary effort by humankind in one the most harsh environments on the planet.” According to Prof. Anders Levermann (a climate scientist at PIK, and at Columbia University in America), “The basic trade-off is whether humanity wants to sacrifice Antarctica for [save] the currently inhabited coast regions and cultural heritage that is being built on our shores.” He also notes, “It’s about global metropolises from New York to Shanghai which, in the long-term, will be below the sea level if there is no action.” Dr. Robin Smith who wasn’t involved in this study says that sea level rise is a gradual effect of climate change, but it’s very difficult to reverse. This will increase the severity and frequency of floods in densely populated coastal areas. Dr. Smith, a senior researcher scientist at the National Centre for Atmospheric Science within the Meteorology section of the University of Reading in England is the subject of the study. He commented on the study by saying, “So although such large-scale geoengineering schemes are not impossible, but reducing greenhouse gas emission as quickly as possible, is clearly still the most reliable method to reduce the many adverse effects of climate change.” Robert Larter is a marine geophysicist at the British Antarctic Survey and agrees with Dr. Smith that “any such icesheet geoengineering scheme will only be temporary to buy time.”
