Underwater melting of tidewater glaciers is occurring much faster than previously thought, according to a study which could lead to improved forecasting of climate-driven sea level rise.
The findings, published in the journal Science, are based on a new method developed by the researchers that for the first time directly measures the submarine melting of tidewater glaciers -- valley glaciers that flow all the way down to the ocean.
“Tidewater glaciers around the globe -- in Greenland, Alaska, Antarctica and beyond -- are retreating and raising sea levels globally,” said Rebecca Jackson, an oceanographer at Rutgers University-New Brunswick in the US.
“Submarine melting has been implicated as a trigger for this glacier retreat, but we have had no direct measurements of melting, let alone how it might vary in time,” Jackson said.
The study shows that the prevailing theory for melt significantly underestimates melt rates.
“These results suggest a stronger coupling between the ocean and glacier than previously expected, and our work provides a path forward to improving our understanding of how the ocean impacts glaciers,” she said.
The scientists studied the underwater melting of the LeConte Glacier, a tidewater glacier in Alaska, from 2016-2018.