Antarctic ice melting faster than thought

A new model suggests Antarctica’s ice shelves may be melting faster than previously thought. This model accounts for an often overlooked narrow ocean current along the Antarctic coast.

The model simulates how rapidly flowing freshwater, melted from the ice shelves, can trap dense warm ocean water at the base of the ice, causing it to warm and melt.

Ice shelves are outcroppings of the Antarctic ice sheet where the ice juts out from land and floats on top of the ocean. The shelves are several hundred meters thick and act as a protective barrier for the mainland ice, keeping the whole ice sheet from flowing into the ocean. 

“If this mechanism that we’ve been studying is active in the real world, it may mean that ice shelf melt rates are 20 to 40 percent higher than the predictions in global climate models, which typically cannot simulate these strong currents near the Antarctic coast,” said Andy Thompson, lead author of the study.

“Large global climate models don’t include this coastal current, because it’s very narrow—only about 20 kilometers wide, while most climate models only capture currents that are 100 kilometers across or larger,” senior researcher Mar Flexas explains. “So, there is a potential for those models to not represent future melt rates very accurately.”

www.scitechdaily.com/antarcticas-ice-shelves-could-be-melting-even-faster-than-we-thought/