Since the early 2000s, scientists have observed that the Antarctic ice sheet is losing mass at a rate that is accelerating.
Since the early 2000s, scientists have observed that the Antarctic ice sheet is losing mass at a rate that is accelerating. The ice sheet is a very thick expanse of ice that can cover an entire continent. There are only two ice sheets on Earth: the Greenland ice sheet, which is limited to the land cover, and the Antarctic ice sheet, which extends beyond the continent into the ocean to form large floating platforms. “These ice shelves act like dams and keep the ice on the continent," explains Christoph Kittel, a researcher at the ULiège Climatology Laboratory (SPHERES research unit / Faculty of Science) and co-author of the study published in the journal Geophysical Research Letters (1). Without these platforms, huge amounts of ice would flow directly into the ocean, leading to a consequent rise in sea levels.”
In summer, the snow on the surface of these platforms melts and water seeps into the small empty spaces in the deep snow layers where it can refreeze and restore the strength of the platform. If the melt is too great, then the excess water seeps deeper into the ice or forms lakes on the surface. The seepage and increased weight of the water as a result of lake formation tends to fracture the ice. And when the ice melt is greater than the snowfall, there is a high risk of platform failure. "The break-up and disappearance of the Larsen B platform in 2002 showed how sensitive these barriers are to melting," explains Ella Gilbert, co-author of the scientific paper and a researcher in the Department of Meteorology at the University of Reading. "In a few days, about 3250 km2 (an area comparable to the province of Liège) of ice has been dumped into the ocean.”
Read more at: University of Liege
Projection of the area of Antarctic shelves that will experience excess surface meltwater. (Photo Credit: ULiège)
