Scientists revealed on Monday that a significant glacier in northwest Greenland is interacting with the ocean tides, leading to hitherto unaccounted-for melting and perhaps accelerated sea level rise.
The report was released on Monday in the Proceedings of the National Academy of Sciences by a group of glaciologists from the University of California, Irvine and NASA’s Jet Propulsion Laboratory.
The grounding line of the Petermann Glacier, which is where the ice sheet starts to protrude out onto the ocean, can move considerably as the tides come in and out each day, according to observations made from the glacier.
Enrico Cirac, the study’s primary author and a scientist at the University of Genoa, stated that Petermann’s grounding line “migrates between 2 and 6 kilometres (1.2 to 3.7 miles) as tides come in and out.”
This discovery is significant: Traditional scientific thinking held that the grounding line does not move with the tides, which presents another significant melting source that could hasten sea level rise.
Warmer tidal cycles between 2016 and 2022 melted a 670-foot-tall crater big enough to fit two Statues of Liberty piled on top of one another inside the glacier along the grounding line.
As ocean temperatures rise, the issue may get worse during the ensuing decades. According to a recent CNN report, sea surface temperatures reached their highest levels ever this spring, a jump that has startled scientists who fear it may be a sign of a troubling new trend.
The findings adds to existing worries about the threat that sea level rising poses to coasts all over the world. According to NASA, the main cause of the sea level rise, which has been accelerated recently, is the melting of Greenland’s ice. However, the fresh contribution from under-ice interactions with warmer tides is not taken into account by present projections.
“These ice-ocean interactions make the glaciers more sensitive to ocean warming,” said co-author and UCI professor Eric Rignot. “These dynamics are not included in models, and if we were to include them, it would increase projections of sea level rise by up to 200 percent – not just for Petermann but for all glaciers ending in the ocean, which is the majority of northern Greenland and the entire continent of Antarctica,” the study stated.