Climate change accelerating rising sea levels

A new study from the University of Waterloo discovered that rising sea levels could be accelerated by vulnerable ice shelves in the Antarctic.

The study, by an international team of polar scientists led by Canada Research Chair and Water Institute member Christine Dow, discovered that the process of warmer ocean water destabilizing ice shelves from below is also cracking them apart from above, increasing the chance they’ll break off.

The front of Nansen Ice Shelf. Photo credits: Canada Research Chair Christine Dow of the University of Waterloo’s Faculty of Environment.

The study, which was conducted over two years, applied methods similar to forensic science on ice shelves which had already calved. Using radar surveys and Landsat imagery, Dow reports direct evidence that a major 2016 calving event at Nansen Ice Shelf in the Ross Sea was the result of fracture driven by channels melted into the bottom of the ice shelf. The surveys also demonstrated that similar basal channel-driven transverse fractures occur elsewhere in Greenland and Antarctica.

As warmer salt water erodes channels into the ice that attaches glaciers to stable land, it also generates massive vertical fractures splitting glaciers from above and below. Surface water melting on top of the ice shelves then pours into these cracks, accelerating the problem further.

“This study is more evidence that the warming effects of climate change are impacting our planet in ways that are often more dangerous than we perhaps had thought,” said Dow. “There are many more vulnerable ice shelves in the Antarctic that, if they break up, will accelerate the processes of sea level rise.”

The study, titled Basal channels drive active surface hydrology and transverse ice shelf fracture, was recently published in AAAS Science Advances.