Canadian scientist examines melting Antarctic glacier, potential sea level rise - CTV News

As icebergs drifted by his Antarctica-bound ship, David Holland spoke this week of how the melting glacier he's cruising towards may contain warning signals for the coasts of far-off Canada.

"The question of whether sea level will change can only be answered by looking at the planet where it matters, and that is at Thwaites," said Holland, director of the environmental fluid dynamics laboratory at New York University, during a satellite phone interview from aboard the South Korean icebreaker Araon.

A glacier can't survive that," said Holland.

Some media have dubbed Thwaites the "doomsday glacier" due to estimates that it could add about 65 centimetres to global sea level rise.

"We want to pay attention to things that are plausible, and rapid collapse of that glacier is a possibility," he said.

All of the mechanisms must be carefully observed to prove or disprove models on the rates of melting, said Holland.

This is how Antarctica can retreat, these kinds of specific events," he said.

The implications of the glacier work reach back to Atlantic Canada -- which along with communities along the Beaufort Sea and in southwestern British Columbia is the region most vulnerable to sea level rise in the country, according to federal scientists

Everything from how to calculate the future height of dikes at the low-lying Chignecto Isthmus -- the narrow band of land that connects Nova Scotia to the rest of the country -- to whether the Fraser River lowlands may face flooding is potentially affected by glacial melting in Antarctica, he said

Based largely on Intergovernmental Panel on Climate Change reports that refer to them as low-probability "tipping point" theories, the 2019 report invoked the possibility of one metre of sea level rise by 2100

However, Blair Greenan, a federal oceanographer who oversaw the relevant chapter of the report, said in a recent interview that a rise in global sea levels approaching two metres by 2100 and five metres by 2150 "cannot be ruled out" due to uncertainty over ice sheet processes like Thwaites

"We don't know, nobody knows," Holland said

One study by Ian Joughin, a University of Washington glaciologist, has suggested Thwaites will only lose ice at a rate that creates sea level rise of one millimetre per year -- and not until next century

However, Joanna Eyquem, a Montreal-based geoscientist who is studying ways to prepare infrastructure for rising sea levels, said in a recent email that glacier research shows sea level forecasts "are constantly evolving," and adaptation efforts need to be quicker