The retreat of Antarctica’s fast-flowing Thwaites Glacier is expected to speed up within 20 years, once the glacier detaches from an underwater ridge that is currently holding it back, says a new study in Geophysical Research Letters.
New seafloor topography off Antarctica’s Thwaites Glaciers leads scientists to predict accelerated melting in the next 20 years. (Credit: Frank Nitsche, Lamont-Doherty)
Thwaites Glacier, which drains into west Antarctica’s Amundsen Sea, is being closely watched for its potential to raise global sea levels as the planet warms. Neighboring glaciers in the Amundsen region are also thinning rapidly, including Pine Island Glacier and the much larger Getz Ice Shelf. The study is the latest to confirm the importance of seafloor topography in predicting how these glaciers will behave in the near future.
Scientists had previously identified a rock feature off west Antarctica that appeared to be slowing the glacier’s slide into the sea. But this study is the first to connect it to a larger ridge, using geophysical data collected during flights over Thwaites Glacier in 2009 under NASA’s Ice Bridge campaign. The newly discovered ridge is 700 meters tall, with two peaks—one that currently anchors the glacier and another farther off shore that held the glacier in place between 55 and 150 years ago, according to the authors.
The goal of NASA’s Ice Bridge campaign is to map the topography of vulnerable regions like this in Antarctica and Greenland by flying over the ice sheets with ice-penetrating radar and other instruments.
The discovery that Thwaites is losing its grip on a previously unknown ridge has helped scientists understand why the glacier seems to be moving faster than it used to.
As scientists map the contours of the seafloor in the Amundsen Sea region, they are forming a clearer picture of what the glaciers are doing. In 2009, researchers sent a robot submarine beneath Pine Island Glacier’s floating ice tongue and discovered a ridge about half the size of the one off Thwaites Glacier. Researchers estimate that Pine Island Glacier lifted off that ridge in the 1970s, allowing warm ocean currents to melt the glacier from below. The glacier’s ice shelf is now moving 50 percent faster than it was in the early 1990s, Lamont-Doherty oceanographer Stan Jacobs and colleagues detailed in a study in Nature Geoscience earlier this year. Pine Island Glacier is moving into the sea at the rate of 4 kilometers a year—four times faster than the fastest-moving section of Thwaites.
Lamont-Doherty geophysicist Robin Bell, study co-author, compares the ridge in front of Thwaites to a person standing in a doorway, holding back a crowd. “Knowing the ridge is there lets us understand why the wide ice tongue that used to be in front of the glacier has broken up,” she said. “We can now predict when the last bit of floating ice will lift off the ridge. We expect more ice will come streaming out of the Thwaites Glacier when this happens.”
“The bathymetry is the roadmap for how warm ocean water reaches the edges of the ice sheet,” she added. “Ridges like this one and the one discovered in front of Pine Island Glacier stabilize ice sheets, but can also be a critical part of the destabilizing process.”Related Links:
Kim Martineau | EurekAlert!
Fast rising bedrock below West Antarctica reveals an extremely fluid Earth mantle
22.06.2018 | Technical University of Denmark
Polar ice may be softer than we thought
22.06.2018 | Eberhard Karls Universität Tübingen
In a recent publication in the renowned journal Optica, scientists of Leibniz-Institute of Photonic Technology (Leibniz IPHT) in Jena showed that they can accurately control the optical properties of liquid-core fiber lasers and therefore their spectral band width by temperature and pressure tuning.
Already last year, the researchers provided experimental proof of a new dynamic of hybrid solitons– temporally and spectrally stationary light waves resulting...
Scientists from the University of Freiburg and the University of Basel identified a master regulator for bone regeneration. Prasad Shastri, Professor of...
Moving into its fourth decade, AchemAsia is setting out for new horizons: The International Expo and Innovation Forum for Sustainable Chemical Production will take place from 21-23 May 2019 in Shanghai, China. With an updated event profile, the eleventh edition focusses on topics that are especially relevant for the Chinese process industry, putting a strong emphasis on sustainability and innovation.
Founded in 1989 as a spin-off of ACHEMA to cater to the needs of China’s then developing industry, AchemAsia has since grown into a platform where the latest...
The BMBF-funded OWICELLS project was successfully completed with a final presentation at the BMW plant in Munich. The presentation demonstrated a Li-Fi communication with a mobile robot, while the robot carried out usual production processes (welding, moving and testing parts) in a 5x5m² production cell. The robust, optical wireless transmission is based on spatial diversity; in other words, data is sent and received simultaneously by several LEDs and several photodiodes. The system can transmit data at more than 100 Mbit/s and five milliseconds latency.
Modern production technologies in the automobile industry must become more flexible in order to fulfil individual customer requirements.
An international team of scientists has discovered a new way to transfer image information through multimodal fibers with almost no distortion - even if the fiber is bent. The results of the study, to which scientist from the Leibniz-Institute of Photonic Technology Jena (Leibniz IPHT) contributed, were published on 6thJune in the highly-cited journal Physical Review Letters.
Endoscopes allow doctors to see into a patient’s body like through a keyhole. Typically, the images are transmitted via a bundle of several hundreds of optical...
13.06.2018 | Event News
08.06.2018 | Event News
05.06.2018 | Event News
22.06.2018 | Materials Sciences
22.06.2018 | Earth Sciences
22.06.2018 | Life Sciences