The Thwaites glacier, also known as Doomsday glacier, is one of the most contentious in West Antarctica and has been retreating for several years. Recent seafloor photos taken by a robot vehicle provide scientists with a better idea of what the glacier may look like in the future.
Seafloor Images of West Antarctica's Thwaites Glacier
The new collection of high-quality photos of the seafloor in front of the glacier raises concerns in a recent study headed by marine geophysicist Alastair Graham of the College of Marine Science at the University of South Florida and published in Nature Geoscience. Researchers can see from the photos how quickly Thwaites advanced and subsided in the past.
Geologic features that are unknown to science are shown in the photograph. It paints a precise picture of its potential behavior in the future. The researchers identified more than 160 parallel ridges.
These ridges developed as the glacier's leading edge retreated and swung back and forth daily in reaction to the tides, forming a pattern like a footprint.
Graham described it as if you are looking at a tide gauge on the seafloor.
"It really blows my mind how beautiful the data are," he said.
Analysis of the Latest Seafloor Images of the Thwaites Glacier
The rib-like features in the 700-meter-deep arctic ocean were inspected by the experts. They took into account the region's tidal cycle to demonstrate that one rib must have formed daily. Computer models have predicted this.
The data indicates that, some 200 years ago, the front of the glacier lost contact with a ridge on the seafloor. It retreated at a rate of more than 2.1 kilometers per year (1.3 miles per year) for less than six months, which is twice the rate seen by satellites between 2011 and 2019.
According to Graham, the findings imply that the Thwaites glacier has seen pulses of extremely rapid retreat over the past two centuries, maybe as recently as the mid-20th century.
Robot Vehicle Captures the Image of the Latest Seafloor Images of the Thwaites Glacier
Scientists from Sweden, the United Kingdom, and the United States launched Rán, a cutting-edge orange robotic vehicle filled with imaging sensors, from the R/V Nathaniel B. Palmer during an expedition in 2019. It was done to gather the imagery and accompanying geophysical data.
According to Graham, Rán, developed and maintained by researchers at the University of Gothenburg in Sweden, set off on a 20-hour journey that was both dangerous and fortunate. It did it in harsh conditions during a summer that was unique for its lack of sea ice, mapping a portion of the seabed in front of the glacier about the size of Houston.
The groundbreaking study of the ocean floor was made possible by recent technological developments in autonomous ocean mapping and a bold choice by the Wallenberg foundation to invest in this research infrastructure, according to Anna Whlin, a physical oceanographer from the University of Gothenburg who deployed Rán at Thwaites.
Whlin added that we could learn a lot about the current activities taking place at the crucial intersection of the glacier and the ocean thanks to the photographs Rán gathered.
