By Antonio Manaytay
Sea level rise will speed up as Antarctic ice shelves can disappear faster than expected, scientists warned.
As the atmosphere continues to warm, at least half of the ice shelves lie vulnerable, they said.
In a study published on August 26 in Nature, the team of scientists said up to 70 percent of the ice shelves that keep Antarctic glaciers intact could collapse because of the surge of meltwater.
Study lead author Ching Yao Lai said it is not only the amount of melting is important, where it melted also matters. Lai is a postdoctoral researcher in Lamont-Doherty Earth Observatory of the Department of Marine Geology & Geophysics at Columbia University in New York.
Lai and her team focused on the ice shelves that act as support or brace. This kind of ice shelves helped slow down the slide of glaciers into the sea.
These shelves have cracks over time because the drifting glaciers pushed them from behind. As it pushes to the shoreline, these shelves also cracked.
Flowing into the ocean, the velocity of the ice shelves caused it to stretch out.
The front of ice shelves usually stretches the fastest, causing the breaking up, Lai, in an interview with Live Science, said.
While warmer temperatures cause the melting of the ice shelf, the cracks deepen as melted water pool on the cracks. This process is called hydro fracture.
Sometimes this deepening of cracks will lead to collapse of the ice shelf.
The melted water can “punch through the ice” in just minutes and hours.
Ocean water can fill up the crack, causing it to break up, Christine Dow told Live Science. Dow is the Canada Research Chair of the University of Waterloo’s Glacier Hydrology and Ice Dynamics.
The phenomenon could have been the underlying dynamic to Larsen B, an ice shelf, in 2002. Larsen B had lost about 3,250 square kilometers (1,225 square miles) in just few weeks.
Sea level rise
Next, Lai and her team had to answer the question how hydro fracture can cause sea level rise.
To answer this question, they pair their findings with climate predictions and how the ice flow from the Antarctic to the ocean.
The research, according to the authors, will help them determine the change of sea level rise because of the melting of ice shelves.
In the absence of such study, several scientists have already predicted the massive calving of ice shelves in Antarctica in just a matter of decades.