This process is called glacioisostasis. post-glacial rebound), and new research suggests it will have a huge impact on future global sea level rise.
“With nearly 700 million people living in coastal areas and the potential costs of sea level rise by the end of the century reaching trillions of dollars, understanding the effects of melting Antarctic ice is critical,” says glaciologist Natalija Gomez of McGill University in Canada.
Gomez and colleagues studied the Earth’s mantle beneath the Antarctic ice sheet and found that it is particularly soft in some key areas. Seismic data revealed that this accounts for the unexpectedly rapid uplift of the continent.
“Our measurements show that the solid ground that forms the base of the Antarctic ice sheet is changing shape surprisingly quickly. The uplift of the Earth due to reduced ice on the surface is no longer taking place in thousands of years, but in decades,” says Terry Wilson, a geologist at Ohio State University (USA).
The research team also used 3D simulations to study how global sea levels would change due to changes in Antarctica under different scenarios. It turned out that if the level of global warming remains low, it will contribute to the fact that by 2500 the sea level will rise to 1.7 m, but if the burning of unprecedented amounts of fossil fuels continues, this level will rise even to 19.5 m.
This is because when ice sheet retreat exceeds uplift, more water is pushed into the oceans. But if we can slow this ice melting, the rising land will push some of the ice away from the warmer ocean waters, so the ice will stay unmelted for longer.
Because the Earth is not a perfectly shaped sphere, gravity, rotation, and geological features will cause sea levels to rise differently in different parts of our planet.
“Our results further support recent findings that nearer-equatorial islands and pendant areas already affected by sea-level rise will experience higher-than-average sea-level rise associated with Antarctic ice loss, regardless of the ice-melt scenario,” he says. scientists.
The researchers caution that there is still a lot of uncertainty in the model, partly because of a lack of seismic data from West Antarctica. In addition, these estimates do not even take into account what is currently happening with Greenland and mountain ice, according to Science Alert.
The study is published in Science Advances.
2024-09-01 22:12:35