Animals

Reindeer can sleep while chewing

By Laura Sanders an hour ago

Life

Has the Endangered Species Act succeeded in reaching its fiftieth year?

By Brianna Randall 5 hours ago

Life

These scientific discoveries broke records in 2023

By Maria Temming on December 21, 2023

Here’s how you can give a good gift according to science

By Sujata Gupta 4 hours ago

Life

These scientific discoveries broke records in 2023

By Maria Temming on December 21, 2023

Earth

Here are some big scientific claims that caught attention in 2023

By Maria Temming on December 15, 2023

“Steve” and other aurora-like glows confound scientists with their complex physics

By Maria Temming on December 20, 2023

Earth

Small obstacles beneath Thwaites ice could help slow its flow into the sea

By Nick Ogasawara on December 19, 2023

Physics

Invisible comet tails of slime slow down marine snow accumulation

By Emily Conover on December 18, 2023

“Steve” and other aurora-like glows confound scientists with their complex physics

By Maria Temming on December 20, 2023

Earth

Small obstacles beneath Thwaites ice could help slow its flow into the sea

By Nick Ogasawara on December 19, 2023

Physics

Invisible comet tails of slime slow down marine snow accumulation

By Emily Conover on December 18, 2023

These scientific discoveries broke records in 2023

By Maria Temming on December 21, 2023

Earth

“Steve” and other aurora-like glows confound scientists with their complex physics

By Maria Temming on December 20, 2023

Space

In 2023, space missions explored the Moon, asteroids, and more

By Erin Wayman on December 20, 2023

These scientific discoveries broke records in 2023

By Maria Temming on December 21, 2023

Earth

“Steve” and other aurora-like glows confound scientists with their complex physics

By Maria Temming on December 20, 2023

Space

In 2023, space missions explored the Moon, asteroids, and more

By Erin Wayman on December 20, 2023

“Steve” and other aurora-like glows confound scientists with their complex physics

By Maria Temming on December 20, 2023

Physics

Invisible comet tails of slime slow down marine snow accumulation

By Emily Conover on December 18, 2023

Quantum Physics

A rebellious physicist builds a case for shedding quantum gravity

By Emily Conover on December 8, 2023

“Steve” and other aurora-like glows confound scientists with their complex physics

By Maria Temming on December 20, 2023

Physics

Invisible comet tails of slime slow down marine snow accumulation

By Emily Conover on December 18, 2023

Quantum Physics

A rebellious physicist builds a case for shedding quantum gravity

By Emily Conover on December 8, 2023

“Steve” and other aurora-like glows confound scientists with their complex physics

By Maria Temming on December 20, 2023

Physics

Invisible comet tails of slime slow down marine snow accumulation

By Emily Conover on December 18, 2023

Quantum Physics

A rebellious physicist builds a case for shedding quantum gravity

By Emily Conover on December 8, 2023

Small speed bumps beneath Thwaites ice could help slow its flow into the sea

By Nick Ogasawara on December 19, 2023

Thwaites Ice in Antarctica (shown in the image) is currently melting and contributing about 4 percent to global sea level rise.

Ted Scambos / University of Colorado

San Francisco – Most news surrounding Thwaites Ice, a sheet of ice the size of Florida that is melting and currently contributing about 4 percent to global sea level rise, is bad. But there might be some good news emerging.

A seismic study of the bedrock beneath part of the Thwaites glacier showed high and hilly terrain underneath the polar ice, which is equivalent to the height of skyscrapers in Manhattan, according to glaciologist Quinn Hofstede on December 12 during a press conference at the American Geophysical Union’s fall meeting. These rugged heights might be gripping the ice’s bottom, slowing its flow toward the ocean and reducing global sea level rise.

It flows

Glaciers flow similarly to rivers, but at a slower pace. Where Thwaites drains into the ocean, it connects to an ice shelf that supports and restrains the ice. This ice shelf was once anchored to a mountain beneath the water, which helped stabilize it. However, now the ice shelf has significantly deteriorated to the point where it is no longer attached to the underwater mountain, according to glaciologist Erin Pettit at a news event.

Fortunately, the glacier “won’t suddenly flow off the land,” thanks to what was discovered beneath, according to Pettit, who was not involved in the discovery. To image the bottom of Thwaites, researchers used a vehicle similar to a tractor (background, middle) to tow a seismic vibratory truck on skis, along with a series of 1.5-kilometer-long seismic sensors (foreground) across the ice surface. The vibrating truck was accompanied across the ice by a train consisting of a food, sleeping, and repair cart.

The seismic waves revealed elevations beneath Thwaites of 10 to 20 kilometers covered by mounds of sediments. These mounds reached heights of up to 100 meters above the elevations and extended several kilometers horizontally.

The data showed that the faces of these mounds at the top appear to be under greater pressure than their lower sides, and there may be layers of deformed ice within the glacier above the elevations. Hofstede hypothesizes that the elevations and mounds slow Thwaites’ flow as they push against the ice.

Scientists used computers to simulate the flow of Thwaites Glacier and showed that it “stumbles over the high features,” according to glaciologist Ben Smith from the University of Washington in Seattle, who was not involved in the work.

The elevations may be related to a system of cracks, an area where tectonic forces have ripped the ground apart, with these cracks extending beneath Thwaites almost vertically to the ice flow, resembling small obstacles on streets.

The results will allow for more detailed simulations of glacier evolution, according to Hofstede, which is crucial for understanding sea-level rise rates.

Do you have questions or comments about this article? You can email us at [email protected]

References:

C. Hofstede et al. The bed of Thwaites Glacier: Characteristics derived from a 208 km seismic profile of the center flow line. American Geophysical Union annual meeting, San Francisco, December 13, 2023.

Nick Ogasawara is a writer for the Science News team focusing on physical sciences. He holds a master’s degree in geology from McGill University and a master’s degree in science communication from the University of California, Santa Cruz.

Source: https://www.sciencenews.org/article/speed-bumps-thwaites-glacier