Tagged in: 爱上海319龙凤

Scientists propose dumping 7400 gigatons of artificial snow on Antarctica

first_img Sci-Tech Tags 19 Comments NASA scopes out Antarctica’s ice (photos)center_img 15 Photos Share your voice Antarctica’s ice sheets are in trouble. Mlenny/Getty What can we do to stop Antarctica’s ice sheets from disintegrating and causing a huge rise in global sea levels? A trio of scientists have simulated a radical geoengineering project to dump 7.4 trillion tons of snow on Antarctica, suggesting it could stop runaway instability in the glaciers.Recent studies have shown warmer ocean water is being pushed toward the colossal West Antarctic ice sheet, destabilizing it and speeding up the decline of its huge glaciers. The threat of these huge ice deposits falling into the ocean is immense and the overall effect of their decline has been calculated to eventually raise sea levels by approximately 10 feet (3 meters) or more, endangering cities like New York.”The real concern is that many of these glaciers have a reverse bed slope, meaning that as they retreat it exposes deeper and thicker ice to the ocean,” explains Sue Cook, a glaciologist at the University of Tasmania. “That is a very unstable position, and causes a positive feedback effect which accelerates the retreat (and hence contribution to sea level rise).”The new study, published in the journal Science Advances on July 17, proposes a drastic, decades-long geoengineering project that would pump huge amounts of ocean water to the ice sheet, adding 7,400 gigatons (7.4 trillion tons) of “artificial snowfall” and reversing the decline. Simulating the current effects on Antarctica’s ice sheets and the changes they experience with increasing snowfall, the researchers were able to map out a process that could potentially halt the ice loss.The problem? Their suggestion would be an incredibly expensive undertaking and include immense technical challenges. The authors say it would present an “unprecedented effort for humankind.”Mostly, the problem lies in pumping the water out of the ocean, which requires an enormous amount of energy. The study suggests constructing a series of 12,000 wind turbines to enable this process to take place and then pumping artificial snow into two glaciers on the West Antarctic coast. The team suggest that activity would result in a 2 to 5 centimeter drop in sea level but the added weight of artificial snow falling on the surface would shore up the glaciers, improving their stability.And the larger effects of such a scheme are yet to be ironed out. What are the lasting effects on the Antarctic ecosystem and what kind of knock-on effects would we see in ocean currents across the world? We just don’t have answers to those questions right now.What we do know is the Earth’s current default state: Burning fossil fuels and pumping tons of carbon into the atmosphere, warming the planet and causing sweeping changes like threatening a million species with extinction or, you know, the ice sheets melting. Considering the possibility of salvation in artificial Antarctic snow might be jumping a little far ahead.”Even if a geoengineering project such as this were possible, it certainly shouldn’t detract from the other urgent action which is required to reduce greenhouse gas emissions,” Cook notes.last_img read more