Drainage of ice from the massive Thwaites Glacier to the Amundsen Sea in West Antarctica is already causing nearly 4% of global sea level rise, and scientists say it is highly susceptible to climate change.
Over the past three decades, the rate of ice loss from the Thwaites, about the size of Great Britain or the U.S. state of Florida, and its neighboring glaciers has increased more than five times.
If the Thwaites are to collapse, it could lead to an increase in sea level of approximately 25 inches (64 centimeters) ̵1; and researchers are trying to figure out how easily this can happen.
Scientists from the International Thwaites Glacier Collaboration (ITGC) collected the data by flying over the glacier aboard a British Antarctic Survey (BAS) Twin Otter aircraft and mapping the ocean floor from the US Antarctic Program icebreaker RV Nathaniel B. Palmer.
Caves hidden under the ice shelf are likely the route through which warm sea water passes under the ice shelf to the grounding line, they said.
“The Thwaites Glacier itself is probably one of the most important glaciers in West Antarctica, because it is so large, because we see it changing now,” said Drs. Tom Jordan, an aero-geophysicist at BAS who led the survey in the air, told CNN.
“And also, we know that its bed sinks, and it deepens under the ice, which means, theoretically, you get a process called ice ice sheet instability. And once it starts to recede, it’s backwards. “
Jordan said the next stage was to include data from the channels, some of which were 2,600 feet (800 meters) deep, in simulations of how the ice sheet would respond in the future.
Earlier today, he said, the ITGC had not accurately accounted for rising sea levels in West Antarctica “because there was so much uncertainty about understanding ice processes and how glaciers would respond over time. . ”
“I think this is a big step towards helping to understand that,” he added.
Jordan said geoengineering and blocking channel suggestions are not possible in a remote location in a logical area. A simpler solution is to “deal with climate change.”
“Ultimately, we can tell governments and policy makers, this is what will happen … we will definitely have a good, restrained estimate of what will happen in the Thwaites Glacier,” Jordan said.
When scientists show the expected sea level rise associated with West Antarctica, he said, they will have more evidence when calling for action to mitigate climate change.
The team collected data from glacier and adjoining Dotson and Crosson ice shelves from January to March 2019. Extraordinary ice-breaking in early 2019 allowed the icebreaker to survey more than 2,000 square square of the sea floor in front of the glacier ice.
The area examined was hidden beneath part of the floating ice shelf extending from the Thwaites Glacier, which was cut off in 2002, and then often inaccessible due to the thick sea-ice cover.