Could building massive gates at the bottom of the sea around Antarctica help slow the rise in sea level?

Large-scale geoengineering projects that would involve the construction of walls and berms along the seabed could help stem the collapse of the western Antarctic ice sheet and the slow rise in sea level. The cryosphere.

Geoscientist Michael Wolovick of Princeton University and climatologist John Moore of the Beijing Normal University examined how different physical barriers could hold a glacier melting or preventing hot water from reaching the lower part of the glacier. They focused their modeling on the Thwaites Glacier, the size of Florida, one of the largest in the world, 50 to 60 miles around the world.

The researchers found that the construction of mounds or columns of sand or gravel dispersed over 1000 feet high on the seafloor had a 30% chance of preventing a collapse of the ice sheet. Western Antarctic in the foreseeable future. A more ambitious project – building a small continuous wall at the edge of a glacier – could prevent about 50% of hot water from reaching the bottom of the ice and 70% chance of reaching the bottom of the ice. prevent the collapse of the icecap over the next 1000 years.

"The most important result [of our study] "Significant ice cap intervention is largely in the order of magnitude of plausible human achievements," Wolovick said in a statement.

However, Wolovick and Moore warn that projects, which they call "glacier geoengineering," will be extremely expensive and time-consuming. Antarctica is one of the most challenging environments in the world. And although seabed barriers can help slow melting down, they do not do anything against the warm air that melts the ice from above.

Scientists also insist that glacier geoengineering is not a substitute for drastically reducing global greenhouse gas emissions. "There are dishonest elements in society who will try to use our research to oppose the need to reduce emissions," the scientists said in a statement. "Our research does not support this interpretation in any way … The more carbon we emit, the less likely it is that ice sheets will survive in the long term at a level close to their current level."